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cm-14.1
kernel_amazon_mt8127-common/kernel/sched/fair.c
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Stricted 6fa3eb70c0 import PULS_20160108
2018-03-13 20:29:02 +01:00

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/*
* Completely Fair Scheduling (CFS) Class (SCHED_NORMAL/SCHED_BATCH)
*
* Copyright (C) 2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
*
* Interactivity improvements by Mike Galbraith
* (C) 2007 Mike Galbraith <efault@gmx.de>
*
* Various enhancements by Dmitry Adamushko.
* (C) 2007 Dmitry Adamushko <dmitry.adamushko@gmail.com>
*
* Group scheduling enhancements by Srivatsa Vaddagiri
* Copyright IBM Corporation, 2007
* Author: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
*
* Scaled math optimizations by Thomas Gleixner
* Copyright (C) 2007, Thomas Gleixner <tglx@linutronix.de>
*
* Adaptive scheduling granularity, math enhancements by Peter Zijlstra
* Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
*/
#include <linux/latencytop.h>
#include <linux/sched.h>
#include <linux/cpumask.h>
#include <linux/slab.h>
#include <linux/profile.h>
#include <linux/interrupt.h>
#include <linux/mempolicy.h>
#include <linux/migrate.h>
#include <linux/task_work.h>
#include <trace/events/sched.h>
#ifdef CONFIG_HMP_VARIABLE_SCALE
#include <linux/sysfs.h>
#include <linux/vmalloc.h>
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
/* Include cpufreq header to add a notifier so that cpu frequency
* scaling can track the current CPU frequency
*/
#include <linux/cpufreq.h>
#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
#endif /* CONFIG_HMP_VARIABLE_SCALE */
#include "sched.h"
#include <mtlbprof/mtlbprof.h>
#ifdef CONFIG_MT_LOAD_BALANCE_ENHANCEMENT
#ifdef CONFIG_LOCAL_TIMERS
unsigned long localtimer_get_counter(void);
#endif
#endif
#ifdef CONFIG_HEVTASK_INTERFACE
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#ifdef CONFIG_KGDB_KDB
#include <linux/kdb.h>
#endif
#endif
/*
* Targeted preemption latency for CPU-bound tasks:
* (default: 6ms * (1 + ilog(ncpus)), units: nanoseconds)
*
* NOTE: this latency value is not the same as the concept of
* 'timeslice length' - timeslices in CFS are of variable length
* and have no persistent notion like in traditional, time-slice
* based scheduling concepts.
*
* (to see the precise effective timeslice length of your workload,
* run vmstat and monitor the context-switches (cs) field)
*/
unsigned int sysctl_sched_latency = 6000000ULL;
unsigned int normalized_sysctl_sched_latency = 6000000ULL;
/*
* The initial- and re-scaling of tunables is configurable
* (default SCHED_TUNABLESCALING_LOG = *(1+ilog(ncpus))
*
* Options are:
* SCHED_TUNABLESCALING_NONE - unscaled, always *1
* SCHED_TUNABLESCALING_LOG - scaled logarithmical, *1+ilog(ncpus)
* SCHED_TUNABLESCALING_LINEAR - scaled linear, *ncpus
*/
enum sched_tunable_scaling sysctl_sched_tunable_scaling
= SCHED_TUNABLESCALING_LOG;
/*
* Minimal preemption granularity for CPU-bound tasks:
* (default: 0.75 msec * (1 + ilog(ncpus)), units: nanoseconds)
*/
unsigned int sysctl_sched_min_granularity = 750000ULL;
unsigned int normalized_sysctl_sched_min_granularity = 750000ULL;
/*
* is kept at sysctl_sched_latency / sysctl_sched_min_granularity
*/
static unsigned int sched_nr_latency = 8;
/*
* After fork, child runs first. If set to 0 (default) then
* parent will (try to) run first.
*/
unsigned int sysctl_sched_child_runs_first __read_mostly;
/*
* SCHED_OTHER wake-up granularity.
* (default: 1 msec * (1 + ilog(ncpus)), units: nanoseconds)
*
* This option delays the preemption effects of decoupled workloads
* and reduces their over-scheduling. Synchronous workloads will still
* have immediate wakeup/sleep latencies.
*/
unsigned int sysctl_sched_wakeup_granularity = 1000000UL;
unsigned int normalized_sysctl_sched_wakeup_granularity = 1000000UL;
const_debug unsigned int sysctl_sched_migration_cost = 100000UL;
/*
* The exponential sliding window over which load is averaged for shares
* distribution.
* (default: 10msec)
*/
unsigned int __read_mostly sysctl_sched_shares_window = 10000000UL;
#ifdef CONFIG_CFS_BANDWIDTH
/*
* Amount of runtime to allocate from global (tg) to local (per-cfs_rq) pool
* each time a cfs_rq requests quota.
*
* Note: in the case that the slice exceeds the runtime remaining (either due
* to consumption or the quota being specified to be smaller than the slice)
* we will always only issue the remaining available time.
*
* default: 5 msec, units: microseconds
*/
unsigned int sysctl_sched_cfs_bandwidth_slice = 5000UL;
#endif
#if defined (CONFIG_MTK_SCHED_CMP_LAZY_BALANCE) && !defined(CONFIG_HMP_LAZY_BALANCE)
static int need_lazy_balance(int dst_cpu, int src_cpu, struct task_struct *p);
#endif
/*
* Increase the granularity value when there are more CPUs,
* because with more CPUs the 'effective latency' as visible
* to users decreases. But the relationship is not linear,
* so pick a second-best guess by going with the log2 of the
* number of CPUs.
*
* This idea comes from the SD scheduler of Con Kolivas:
*/
static int get_update_sysctl_factor(void)
{
unsigned int cpus = min_t(int, num_online_cpus(), 8);
unsigned int factor;
switch (sysctl_sched_tunable_scaling) {
case SCHED_TUNABLESCALING_NONE:
factor = 1;
break;
case SCHED_TUNABLESCALING_LINEAR:
factor = cpus;
break;
case SCHED_TUNABLESCALING_LOG:
default:
factor = 1 + ilog2(cpus);
break;
}
return factor;
}
static void update_sysctl(void)
{
unsigned int factor = get_update_sysctl_factor();
#define SET_SYSCTL(name) \
(sysctl_##name = (factor) * normalized_sysctl_##name)
SET_SYSCTL(sched_min_granularity);
SET_SYSCTL(sched_latency);
SET_SYSCTL(sched_wakeup_granularity);
#undef SET_SYSCTL
}
void sched_init_granularity(void)
{
update_sysctl();
}
#if defined (CONFIG_MTK_SCHED_CMP_PACK_SMALL_TASK) || defined (CONFIG_HMP_PACK_SMALL_TASK)
/*
* Save the id of the optimal CPU that should be used to pack small tasks
* The value -1 is used when no buddy has been found
*/
DEFINE_PER_CPU(int, sd_pack_buddy) = {-1};
#ifdef CONFIG_MTK_SCHED_CMP_PACK_SMALL_TASK
struct cpumask buddy_cpu_map = {{0}};
#endif
/* Look for the best buddy CPU that can be used to pack small tasks
* We make the assumption that it doesn't wort to pack on CPU that share the
* same powerline. We looks for the 1st sched_domain without the
* SD_SHARE_POWERLINE flag. Then We look for the sched_group witht the lowest
* power per core based on the assumption that their power efficiency is
* better */
void update_packing_domain(int cpu)
{
struct sched_domain *sd;
int id = -1;
#ifdef CONFIG_HMP_PACK_BUDDY_INFO
pr_info("[PACK] update_packing_domain() CPU%d\n", cpu);
#endif /* CONFIG_MTK_SCHED_CMP_PACK_BUDDY_INFO || CONFIG_HMP_PACK_BUDDY_INFO */
mt_sched_printf("[PACK] update_packing_domain() CPU%d", cpu);
sd = highest_flag_domain(cpu, SD_SHARE_POWERLINE);
if (!sd)
{
sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd);
}
else
if (cpumask_first(sched_domain_span(sd)) == cpu || !sd->parent)
sd = sd->parent;
while (sd) {
struct sched_group *sg = sd->groups;
struct sched_group *pack = sg;
struct sched_group *tmp = sg->next;
#ifdef CONFIG_HMP_PACK_BUDDY_INFO
pr_info("[PACK] sd = 0x%08x, flags = %d\n", (unsigned int)sd, sd->flags);
#endif /* CONFIG_HMP_PACK_BUDDY_INFO */
#ifdef CONFIG_HMP_PACK_BUDDY_INFO
pr_info("[PACK] sg = 0x%08x\n", (unsigned int)sg);
#endif /* CONFIG_HMP_PACK_BUDDY_INFO */
/* 1st CPU of the sched domain is a good candidate */
if (id == -1)
id = cpumask_first(sched_domain_span(sd));
#ifdef CONFIG_HMP_PACK_BUDDY_INFO
pr_info("[PACK] First cpu in this sd id = %d\n", id);
#endif /* CONFIG_HMP_PACK_BUDDY_INFO */
/* Find sched group of candidate */
tmp = sd->groups;
do {
if (cpumask_test_cpu(id, sched_group_cpus(tmp))) {
sg = tmp;
break;
}
} while (tmp = tmp->next, tmp != sd->groups);
#ifdef CONFIG_HMP_PACK_BUDDY_INFO
pr_info("[PACK] pack = 0x%08x\n", (unsigned int)sg);
#endif /* CONFIG_HMP_PACK_BUDDY_INFO */
pack = sg;
tmp = sg->next;
/* loop the sched groups to find the best one */
//Stop find the best one in the same Load Balance Domain
//while (tmp != sg) {
while (tmp != sg && !(sd->flags & SD_LOAD_BALANCE)) {
if (tmp->sgp->power * sg->group_weight <
sg->sgp->power * tmp->group_weight) {
#ifdef CONFIG_HMP_PACK_BUDDY_INFO
pr_info("[PACK] Now sg power = %u, weight = %u, mask = %lu\n", sg->sgp->power, sg->group_weight, sg->cpumask[0]);
pr_info("[PACK] Better sg power = %u, weight = %u, mask = %lu\n", tmp->sgp->power, tmp->group_weight, tmp->cpumask[0]);
#endif /* CONFIG_MTK_SCHED_CMP_PACK_BUDDY_INFO || CONFIG_HMP_PACK_BUDDY_INFO */
pack = tmp;
}
tmp = tmp->next;
}
/* we have found a better group */
if (pack != sg) {
id = cpumask_first(sched_group_cpus(pack));
#ifdef CONFIG_HMP_PACK_BUDDY_INFO
pr_info("[PACK] Better sg, first cpu id = %d\n", id);
#endif /* CONFIG_HMP_PACK_BUDDY_INFO */
}
#ifdef CONFIG_HMP_PACK_BUDDY_INFO
if(sd->parent) {
pr_info("[PACK] cpu = %d, id = %d, sd->parent = 0x%08x, flags = %d, SD_LOAD_BALANCE = %d\n", cpu, id, (unsigned int)sd->parent, sd->parent->flags, SD_LOAD_BALANCE);
pr_info("[PACK] %d\n", (id != cpu));
pr_info("[PACK] 0x%08x\n", (unsigned int)(sd->parent));
pr_info("[PACK] %d\n", (sd->parent->flags & SD_LOAD_BALANCE));
}
else {
pr_info("[PACK] cpu = %d, id = %d, sd->parent = 0x%08x\n", cpu, id, (unsigned int)sd->parent);
}
#endif /* CONFIG_HMP_PACK_BUDDY_INFO */
/* Look for another CPU than itself */
if ((id != cpu) ||
((sd->parent) && (sd->parent->flags & SD_LOAD_BALANCE))) {
#ifdef CONFIG_HMP_PACK_BUDDY_INFO
pr_info("[PACK] Break\n");
#endif /*CONFIG_HMP_PACK_BUDDY_INFO */
break;
}
sd = sd->parent;
}
#ifdef CONFIG_HMP_PACK_BUDDY_INFO
pr_info("[PACK] CPU%d packing on CPU%d\n", cpu, id);
#endif /* CONFIG_MTK_SCHED_CMP_PACK_BUDDY_INFO || CONFIG_HMP_PACK_BUDDY_INFO */
mt_sched_printf("[PACK] CPU%d packing on CPU%d", cpu, id);
#ifdef CONFIG_HMP_PACK_SMALL_TASK
per_cpu(sd_pack_buddy, cpu) = id;
#else /* CONFIG_MTK_SCHED_CMP_PACK_SMALL_TASK */
if(per_cpu(sd_pack_buddy, cpu) != -1)
cpu_clear(per_cpu(sd_pack_buddy, cpu), buddy_cpu_map);
per_cpu(sd_pack_buddy, cpu) = id;
if(id != -1)
cpumask_set_cpu(id, &buddy_cpu_map);
#endif
}
#ifdef CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER
DEFINE_PER_CPU(u32, BUDDY_CPU_RQ_USAGE);
DEFINE_PER_CPU(u32, BUDDY_CPU_RQ_PERIOD);
DEFINE_PER_CPU(u32, BUDDY_CPU_RQ_NR);
DEFINE_PER_CPU(u32, TASK_USGAE);
DEFINE_PER_CPU(u32, TASK_PERIOD);
u32 PACK_FROM_CPUX_TO_CPUY_COUNT[NR_CPUS][NR_CPUS];
u32 AVOID_LOAD_BALANCE_FROM_CPUX_TO_CPUY_COUNT[NR_CPUS][NR_CPUS];
u32 AVOID_WAKE_UP_FROM_CPUX_TO_CPUY_COUNT[NR_CPUS][NR_CPUS];
u32 TASK_PACK_CPU_COUNT[4][NR_CPUS] = {{0}};
u32 PA_ENABLE = 1;
u32 PA_MON_ENABLE = 0;
char PA_MON[4][TASK_COMM_LEN]={{0}};
#endif /* CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER */
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
DEFINE_PER_CPU(u32, BUDDY_CPU_RQ_USAGE);
DEFINE_PER_CPU(u32, BUDDY_CPU_RQ_PERIOD);
DEFINE_PER_CPU(u32, BUDDY_CPU_RQ_NR);
DEFINE_PER_CPU(u32, TASK_USGAE);
DEFINE_PER_CPU(u32, TASK_PERIOD);
u32 PACK_FROM_CPUX_TO_CPUY_COUNT[NR_CPUS][NR_CPUS];
u32 AVOID_LOAD_BALANCE_FROM_CPUX_TO_CPUY_COUNT[NR_CPUS][NR_CPUS];
u32 AVOID_WAKE_UP_FROM_CPUX_TO_CPUY_COUNT[NR_CPUS][NR_CPUS];
u32 HMP_FROM_CPUX_TO_CPUY_COUNT[NR_CPUS][NR_CPUS];
u32 PA_ENABLE = 1;
u32 LB_ENABLE = 1;
u32 PA_MON_ENABLE = 0;
char PA_MON[TASK_COMM_LEN];
#ifdef CONFIG_HMP_TRACER
#define POWER_AWARE_ACTIVE_MODULE_PACK_FORM_CPUX_TO_CPUY (0)
#define POWER_AWARE_ACTIVE_MODULE_AVOID_WAKE_UP_FORM_CPUX_TO_CPUY (1)
#define POWER_AWARE_ACTIVE_MODULE_AVOID_BALANCE_FORM_CPUX_TO_CPUY (2)
#define POWER_AWARE_ACTIVE_MODULE_AVOID_FORCE_UP_FORM_CPUX_TO_CPUY (3)
#endif /* CONFIG_HMP_TRACER */
#endif /* CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER */
static inline bool is_buddy_busy(int cpu)
{
#ifdef CONFIG_HMP_PACK_SMALL_TASK
struct rq *rq;
if (cpu < 0)
return 0;
rq = cpu_rq(cpu);
#else /* CONFIG_MTK_SCHED_CMP_PACK_SMALL_TASK */
struct rq *rq = cpu_rq(cpu);
#endif
/*
* A busy buddy is a CPU with a high load or a small load with a lot of
* running tasks.
*/
#if defined (CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER) || defined (CONFIG_HMP_POWER_AWARE_CONTROLLER)
per_cpu(BUDDY_CPU_RQ_USAGE, cpu) = rq->avg.usage_avg_sum;
per_cpu(BUDDY_CPU_RQ_PERIOD, cpu) = rq->avg.runnable_avg_period;
per_cpu(BUDDY_CPU_RQ_NR, cpu) = rq->nr_running;
#endif /*(CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER) || defined (CONFIG_HMP_POWER_AWARE_CONTROLLER) */
return ((rq->avg.usage_avg_sum << rq->nr_running) >
rq->avg.runnable_avg_period);
}
static inline bool is_light_task(struct task_struct *p)
{
#if defined (CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER) || defined (CONFIG_HMP_POWER_AWARE_CONTROLLER)
per_cpu(TASK_USGAE, task_cpu(p)) = p->se.avg.usage_avg_sum;
per_cpu(TASK_PERIOD, task_cpu(p)) = p->se.avg.runnable_avg_period;
#endif /* CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER || CONFIG_HMP_POWER_AWARE_CONTROLLER*/
/* A light task runs less than 25% in average */
return ((p->se.avg.usage_avg_sum << 2) < p->se.avg.runnable_avg_period);
}
static int check_pack_buddy(int cpu, struct task_struct *p)
{
#ifdef CONFIG_HMP_PACK_SMALL_TASK
int buddy;
if(cpu >= NR_CPUS || cpu < 0)
return false;
buddy = per_cpu(sd_pack_buddy, cpu);
#else /* CONFIG_MTK_SCHED_CMP_PACK_SMALL_TASK */
int buddy = cpu;
#endif
/* No pack buddy for this CPU */
if (buddy == -1)
return false;
/*
* If a task is waiting for running on the CPU which is its own buddy,
* let the default behavior to look for a better CPU if available
* The threshold has been set to 37.5%
*/
#ifdef CONFIG_HMP_PACK_SMALL_TASK
if ((buddy == cpu)
&& ((p->se.avg.usage_avg_sum << 3) < (p->se.avg.runnable_avg_sum * 5)))
return false;
#endif
/* buddy is not an allowed CPU */
if (!cpumask_test_cpu(buddy, tsk_cpus_allowed(p)))
return false;
/*
* If the task is a small one and the buddy is not overloaded,
* we use buddy cpu
*/
if (!is_light_task(p) || is_buddy_busy(buddy))
return false;
return true;
}
#endif /* CONFIG_MTK_SCHED_CMP_PACK_SMALL_TASK || CONFIG_HMP_PACK_SMALL_TASK*/
#if BITS_PER_LONG == 32
# define WMULT_CONST (~0UL)
#else
# define WMULT_CONST (1UL << 32)
#endif
#define WMULT_SHIFT 32
/*
* Shift right and round:
*/
#define SRR(x, y) (((x) + (1UL << ((y) - 1))) >> (y))
/*
* delta *= weight / lw
*/
static unsigned long
calc_delta_mine(unsigned long delta_exec, unsigned long weight,
struct load_weight *lw)
{
u64 tmp;
/*
* weight can be less than 2^SCHED_LOAD_RESOLUTION for task group sched
* entities since MIN_SHARES = 2. Treat weight as 1 if less than
* 2^SCHED_LOAD_RESOLUTION.
*/
if (likely(weight > (1UL << SCHED_LOAD_RESOLUTION)))
tmp = (u64)delta_exec * scale_load_down(weight);
else
tmp = (u64)delta_exec;
if (!lw->inv_weight) {
unsigned long w = scale_load_down(lw->weight);
if (BITS_PER_LONG > 32 && unlikely(w >= WMULT_CONST))
lw->inv_weight = 1;
else if (unlikely(!w))
lw->inv_weight = WMULT_CONST;
else
lw->inv_weight = WMULT_CONST / w;
}
/*
* Check whether we'd overflow the 64-bit multiplication:
*/
if (unlikely(tmp > WMULT_CONST))
tmp = SRR(SRR(tmp, WMULT_SHIFT/2) * lw->inv_weight,
WMULT_SHIFT/2);
else
tmp = SRR(tmp * lw->inv_weight, WMULT_SHIFT);
return (unsigned long)min(tmp, (u64)(unsigned long)LONG_MAX);
}
const struct sched_class fair_sched_class;
/**************************************************************
* CFS operations on generic schedulable entities:
*/
#ifdef CONFIG_FAIR_GROUP_SCHED
/* cpu runqueue to which this cfs_rq is attached */
static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
{
return cfs_rq->rq;
}
/* An entity is a task if it doesn't "own" a runqueue */
#define entity_is_task(se) (!se->my_q)
static inline struct task_struct *task_of(struct sched_entity *se)
{
#ifdef CONFIG_SCHED_DEBUG
WARN_ON_ONCE(!entity_is_task(se));
#endif
return container_of(se, struct task_struct, se);
}
/* Walk up scheduling entities hierarchy */
#define for_each_sched_entity(se) \
for (; se; se = se->parent)
static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
{
return p->se.cfs_rq;
}
/* runqueue on which this entity is (to be) queued */
static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
{
return se->cfs_rq;
}
/* runqueue "owned" by this group */
static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
{
return grp->my_q;
}
static void update_cfs_rq_blocked_load(struct cfs_rq *cfs_rq,
int force_update);
static inline void list_add_leaf_cfs_rq(struct cfs_rq *cfs_rq)
{
if (!cfs_rq->on_list) {
/*
* Ensure we either appear before our parent (if already
* enqueued) or force our parent to appear after us when it is
* enqueued. The fact that we always enqueue bottom-up
* reduces this to two cases.
*/
if (cfs_rq->tg->parent &&
cfs_rq->tg->parent->cfs_rq[cpu_of(rq_of(cfs_rq))]->on_list) {
list_add_rcu(&cfs_rq->leaf_cfs_rq_list,
&rq_of(cfs_rq)->leaf_cfs_rq_list);
} else {
list_add_tail_rcu(&cfs_rq->leaf_cfs_rq_list,
&rq_of(cfs_rq)->leaf_cfs_rq_list);
}
cfs_rq->on_list = 1;
/* We should have no load, but we need to update last_decay. */
update_cfs_rq_blocked_load(cfs_rq, 0);
}
}
static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
{
if (cfs_rq->on_list) {
list_del_rcu(&cfs_rq->leaf_cfs_rq_list);
cfs_rq->on_list = 0;
}
}
/* Iterate thr' all leaf cfs_rq's on a runqueue */
#define for_each_leaf_cfs_rq(rq, cfs_rq) \
list_for_each_entry_rcu(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list)
/* Do the two (enqueued) entities belong to the same group ? */
static inline int
is_same_group(struct sched_entity *se, struct sched_entity *pse)
{
if (se && pse)
{
if (se->cfs_rq == pse->cfs_rq)
return 1;
}
return 0;
}
static inline struct sched_entity *parent_entity(struct sched_entity *se)
{
return se->parent;
}
/* return depth at which a sched entity is present in the hierarchy */
static inline int depth_se(struct sched_entity *se)
{
int depth = 0;
for_each_sched_entity(se)
depth++;
return depth;
}
static void
find_matching_se(struct sched_entity **se, struct sched_entity **pse)
{
int se_depth, pse_depth;
/*
* preemption test can be made between sibling entities who are in the
* same cfs_rq i.e who have a common parent. Walk up the hierarchy of
* both tasks until we find their ancestors who are siblings of common
* parent.
*/
/* First walk up until both entities are at same depth */
se_depth = depth_se(*se);
pse_depth = depth_se(*pse);
while (se_depth > pse_depth) {
se_depth--;
*se = parent_entity(*se);
}
while (pse_depth > se_depth) {
pse_depth--;
*pse = parent_entity(*pse);
}
while (!is_same_group(*se, *pse)) {
*se = parent_entity(*se);
*pse = parent_entity(*pse);
}
}
#else /* !CONFIG_FAIR_GROUP_SCHED */
static inline struct task_struct *task_of(struct sched_entity *se)
{
return container_of(se, struct task_struct, se);
}
static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
{
return container_of(cfs_rq, struct rq, cfs);
}
#define entity_is_task(se) 1
#define for_each_sched_entity(se) \
for (; se; se = NULL)
static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
{
return &task_rq(p)->cfs;
}
static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
{
struct task_struct *p = task_of(se);
struct rq *rq = task_rq(p);
return &rq->cfs;
}
/* runqueue "owned" by this group */
static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
{
return NULL;
}
static inline void list_add_leaf_cfs_rq(struct cfs_rq *cfs_rq)
{
}
static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
{
}
#define for_each_leaf_cfs_rq(rq, cfs_rq) \
for (cfs_rq = &rq->cfs; cfs_rq; cfs_rq = NULL)
static inline int
is_same_group(struct sched_entity *se, struct sched_entity *pse)
{
return 1;
}
static inline struct sched_entity *parent_entity(struct sched_entity *se)
{
return NULL;
}
static inline void
find_matching_se(struct sched_entity **se, struct sched_entity **pse)
{
}
#endif /* CONFIG_FAIR_GROUP_SCHED */
static __always_inline
void account_cfs_rq_runtime(struct cfs_rq *cfs_rq, unsigned long delta_exec);
/**************************************************************
* Scheduling class tree data structure manipulation methods:
*/
static inline u64 max_vruntime(u64 max_vruntime, u64 vruntime)
{
s64 delta = (s64)(vruntime - max_vruntime);
if (delta > 0)
max_vruntime = vruntime;
return max_vruntime;
}
static inline u64 min_vruntime(u64 min_vruntime, u64 vruntime)
{
s64 delta = (s64)(vruntime - min_vruntime);
if (delta < 0)
min_vruntime = vruntime;
return min_vruntime;
}
static inline int entity_before(struct sched_entity *a,
struct sched_entity *b)
{
return (s64)(a->vruntime - b->vruntime) < 0;
}
static void update_min_vruntime(struct cfs_rq *cfs_rq)
{
u64 vruntime = cfs_rq->min_vruntime;
if (cfs_rq->curr)
vruntime = cfs_rq->curr->vruntime;
if (cfs_rq->rb_leftmost) {
struct sched_entity *se = rb_entry(cfs_rq->rb_leftmost,
struct sched_entity,
run_node);
if (!cfs_rq->curr)
vruntime = se->vruntime;
else
vruntime = min_vruntime(vruntime, se->vruntime);
}
/* ensure we never gain time by being placed backwards. */
cfs_rq->min_vruntime = max_vruntime(cfs_rq->min_vruntime, vruntime);
#ifndef CONFIG_64BIT
smp_wmb();
cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime;
#endif
}
/*
* Enqueue an entity into the rb-tree:
*/
static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
struct rb_node **link = &cfs_rq->tasks_timeline.rb_node;
struct rb_node *parent = NULL;
struct sched_entity *entry;
int leftmost = 1;
/*
* Find the right place in the rbtree:
*/
while (*link) {
parent = *link;
entry = rb_entry(parent, struct sched_entity, run_node);
/*
* We dont care about collisions. Nodes with
* the same key stay together.
*/
if (entity_before(se, entry)) {
link = &parent->rb_left;
} else {
link = &parent->rb_right;
leftmost = 0;
}
}
/*
* Maintain a cache of leftmost tree entries (it is frequently
* used):
*/
if (leftmost)
cfs_rq->rb_leftmost = &se->run_node;
rb_link_node(&se->run_node, parent, link);
rb_insert_color(&se->run_node, &cfs_rq->tasks_timeline);
}
static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
if (cfs_rq->rb_leftmost == &se->run_node) {
struct rb_node *next_node;
next_node = rb_next(&se->run_node);
cfs_rq->rb_leftmost = next_node;
}
rb_erase(&se->run_node, &cfs_rq->tasks_timeline);
}
struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq)
{
struct rb_node *left = cfs_rq->rb_leftmost;
if (!left)
return NULL;
return rb_entry(left, struct sched_entity, run_node);
}
static struct sched_entity *__pick_next_entity(struct sched_entity *se)
{
struct rb_node *next = rb_next(&se->run_node);
if (!next)
return NULL;
return rb_entry(next, struct sched_entity, run_node);
}
#ifdef CONFIG_SCHED_DEBUG
struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq)
{
struct rb_node *last = rb_last(&cfs_rq->tasks_timeline);
if (!last)
return NULL;
return rb_entry(last, struct sched_entity, run_node);
}
/**************************************************************
* Scheduling class statistics methods:
*/
int sched_proc_update_handler(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp,
loff_t *ppos)
{
int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
int factor = get_update_sysctl_factor();
if (ret || !write)
return ret;
sched_nr_latency = DIV_ROUND_UP(sysctl_sched_latency,
sysctl_sched_min_granularity);
#define WRT_SYSCTL(name) \
(normalized_sysctl_##name = sysctl_##name / (factor))
WRT_SYSCTL(sched_min_granularity);
WRT_SYSCTL(sched_latency);
WRT_SYSCTL(sched_wakeup_granularity);
#undef WRT_SYSCTL
return 0;
}
#endif
/*
* delta /= w
*/
static inline unsigned long
calc_delta_fair(unsigned long delta, struct sched_entity *se)
{
if (unlikely(se->load.weight != NICE_0_LOAD))
delta = calc_delta_mine(delta, NICE_0_LOAD, &se->load);
return delta;
}
/*
* The idea is to set a period in which each task runs once.
*
* When there are too many tasks (sched_nr_latency) we have to stretch
* this period because otherwise the slices get too small.
*
* p = (nr <= nl) ? l : l*nr/nl
*/
static u64 __sched_period(unsigned long nr_running)
{
u64 period = sysctl_sched_latency;
unsigned long nr_latency = sched_nr_latency;
if (unlikely(nr_running > nr_latency)) {
period = sysctl_sched_min_granularity;
period *= nr_running;
}
return period;
}
/*
* We calculate the wall-time slice from the period by taking a part
* proportional to the weight.
*
* s = p*P[w/rw]
*/
static u64 sched_slice(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
u64 slice = __sched_period(cfs_rq->nr_running + !se->on_rq);
for_each_sched_entity(se) {
struct load_weight *load;
struct load_weight lw;
cfs_rq = cfs_rq_of(se);
load = &cfs_rq->load;
if (unlikely(!se->on_rq)) {
lw = cfs_rq->load;
update_load_add(&lw, se->load.weight);
load = &lw;
}
slice = calc_delta_mine(slice, se->load.weight, load);
}
return slice;
}
/*
* We calculate the vruntime slice of a to-be-inserted task.
*
* vs = s/w
*/
static u64 sched_vslice(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
return calc_delta_fair(sched_slice(cfs_rq, se), se);
}
#ifdef CONFIG_SMP
static inline void __update_task_entity_contrib(struct sched_entity *se);
static long __update_task_entity_ratio(struct sched_entity *se);
#define LOAD_AVG_PERIOD 32
#define LOAD_AVG_MAX 47742 /* maximum possible load avg */
#define LOAD_AVG_MAX_N 345 /* number of full periods to produce LOAD_MAX_AVG */
#define LOAD_AVG_VARIABLE_PERIOD 512
static unsigned int init_task_load_period = 4000;
/* Give new task start runnable values to heavy its load in infant time */
void init_task_runnable_average(struct task_struct *p)
{
u32 slice;
p->se.avg.decay_count = 0;
slice = sched_slice(task_cfs_rq(p), &p->se) >> 10;
p->se.avg.runnable_avg_sum = (init_task_load_period) ? 0 : slice;
p->se.avg.runnable_avg_period = (init_task_load_period)?(init_task_load_period):slice;
__update_task_entity_contrib(&p->se);
#ifdef CONFIG_MTK_SCHED_CMP
/* usage_avg_sum & load_avg_ratio are based on Linaro 12.11. */
p->se.avg.usage_avg_sum = (init_task_load_period) ? 0 : slice;
#endif
__update_task_entity_ratio(&p->se);
trace_sched_task_entity_avg(0, p, &p->se.avg);
}
#else
void init_task_runnable_average(struct task_struct *p)
{
}
#endif
/*
* Update the current task's runtime statistics. Skip current tasks that
* are not in our scheduling class.
*/
static inline void
__update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr,
unsigned long delta_exec)
{
unsigned long delta_exec_weighted;
schedstat_set(curr->statistics.exec_max,
max((u64)delta_exec, curr->statistics.exec_max));
curr->sum_exec_runtime += delta_exec;
schedstat_add(cfs_rq, exec_clock, delta_exec);
delta_exec_weighted = calc_delta_fair(delta_exec, curr);
curr->vruntime += delta_exec_weighted;
update_min_vruntime(cfs_rq);
}
static void update_curr(struct cfs_rq *cfs_rq)
{
struct sched_entity *curr = cfs_rq->curr;
u64 now = rq_of(cfs_rq)->clock_task;
unsigned long delta_exec;
if (unlikely(!curr))
return;
/*
* Get the amount of time the current task was running
* since the last time we changed load (this cannot
* overflow on 32 bits):
*/
delta_exec = (unsigned long)(now - curr->exec_start);
if (!delta_exec)
return;
__update_curr(cfs_rq, curr, delta_exec);
curr->exec_start = now;
if (entity_is_task(curr)) {
struct task_struct *curtask = task_of(curr);
trace_sched_stat_runtime(curtask, delta_exec, curr->vruntime);
cpuacct_charge(curtask, delta_exec);
account_group_exec_runtime(curtask, delta_exec);
}
account_cfs_rq_runtime(cfs_rq, delta_exec);
}
static inline void
update_stats_wait_start(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
schedstat_set(se->statistics.wait_start, rq_of(cfs_rq)->clock);
}
/*
* Task is being enqueued - update stats:
*/
static void update_stats_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
/*
* Are we enqueueing a waiting task? (for current tasks
* a dequeue/enqueue event is a NOP)
*/
if (se != cfs_rq->curr)
update_stats_wait_start(cfs_rq, se);
}
static void
update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
schedstat_set(se->statistics.wait_max, max(se->statistics.wait_max,
rq_of(cfs_rq)->clock - se->statistics.wait_start));
schedstat_set(se->statistics.wait_count, se->statistics.wait_count + 1);
schedstat_set(se->statistics.wait_sum, se->statistics.wait_sum +
rq_of(cfs_rq)->clock - se->statistics.wait_start);
#ifdef CONFIG_SCHEDSTATS
if (entity_is_task(se)) {
trace_sched_stat_wait(task_of(se),
rq_of(cfs_rq)->clock - se->statistics.wait_start);
}
#endif
schedstat_set(se->statistics.wait_start, 0);
}
static inline void
update_stats_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
/*
* Mark the end of the wait period if dequeueing a
* waiting task:
*/
if (se != cfs_rq->curr)
update_stats_wait_end(cfs_rq, se);
}
/*
* We are picking a new current task - update its stats:
*/
static inline void
update_stats_curr_start(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
/*
* We are starting a new run period:
*/
se->exec_start = rq_of(cfs_rq)->clock_task;
}
/**************************************************
* Scheduling class queueing methods:
*/
#ifdef CONFIG_NUMA_BALANCING
/*
* numa task sample period in ms
*/
unsigned int sysctl_numa_balancing_scan_period_min = 100;
unsigned int sysctl_numa_balancing_scan_period_max = 100*50;
unsigned int sysctl_numa_balancing_scan_period_reset = 100*600;
/* Portion of address space to scan in MB */
unsigned int sysctl_numa_balancing_scan_size = 256;
/* Scan @scan_size MB every @scan_period after an initial @scan_delay in ms */
unsigned int sysctl_numa_balancing_scan_delay = 1000;
static void task_numa_placement(struct task_struct *p)
{
int seq;
if (!p->mm) /* for example, ksmd faulting in a user's mm */
return;
seq = ACCESS_ONCE(p->mm->numa_scan_seq);
if (p->numa_scan_seq == seq)
return;
p->numa_scan_seq = seq;
/* FIXME: Scheduling placement policy hints go here */
}
/*
* Got a PROT_NONE fault for a page on @node.
*/
void task_numa_fault(int node, int pages, bool migrated)
{
struct task_struct *p = current;
if (!sched_feat_numa(NUMA))
return;
/* FIXME: Allocate task-specific structure for placement policy here */
/*
* If pages are properly placed (did not migrate) then scan slower.
* This is reset periodically in case of phase changes
*/
if (!migrated)
p->numa_scan_period = min(sysctl_numa_balancing_scan_period_max,
p->numa_scan_period + jiffies_to_msecs(10));
task_numa_placement(p);
}
static void reset_ptenuma_scan(struct task_struct *p)
{
ACCESS_ONCE(p->mm->numa_scan_seq)++;
p->mm->numa_scan_offset = 0;
}
/*
* The expensive part of numa migration is done from task_work context.
* Triggered from task_tick_numa().
*/
void task_numa_work(struct callback_head *work)
{
unsigned long migrate, next_scan, now = jiffies;
struct task_struct *p = current;
struct mm_struct *mm = p->mm;
struct vm_area_struct *vma;
unsigned long start, end;
long pages;
WARN_ON_ONCE(p != container_of(work, struct task_struct, numa_work));
work->next = work; /* protect against double add */
/*
* Who cares about NUMA placement when they're dying.
*
* NOTE: make sure not to dereference p->mm before this check,
* exit_task_work() happens _after_ exit_mm() so we could be called
* without p->mm even though we still had it when we enqueued this
* work.
*/
if (p->flags & PF_EXITING)
return;
/*
* We do not care about task placement until a task runs on a node
* other than the first one used by the address space. This is
* largely because migrations are driven by what CPU the task
* is running on. If it's never scheduled on another node, it'll
* not migrate so why bother trapping the fault.
*/
if (mm->first_nid == NUMA_PTE_SCAN_INIT)
mm->first_nid = numa_node_id();
if (mm->first_nid != NUMA_PTE_SCAN_ACTIVE) {
/* Are we running on a new node yet? */
if (numa_node_id() == mm->first_nid &&
!sched_feat_numa(NUMA_FORCE))
return;
mm->first_nid = NUMA_PTE_SCAN_ACTIVE;
}
/*
* Reset the scan period if enough time has gone by. Objective is that
* scanning will be reduced if pages are properly placed. As tasks
* can enter different phases this needs to be re-examined. Lacking
* proper tracking of reference behaviour, this blunt hammer is used.
*/
migrate = mm->numa_next_reset;
if (time_after(now, migrate)) {
p->numa_scan_period = sysctl_numa_balancing_scan_period_min;
next_scan = now + msecs_to_jiffies(sysctl_numa_balancing_scan_period_reset);
xchg(&mm->numa_next_reset, next_scan);
}
/*
* Enforce maximal scan/migration frequency..
*/
migrate = mm->numa_next_scan;
if (time_before(now, migrate))
return;
if (p->numa_scan_period == 0)
p->numa_scan_period = sysctl_numa_balancing_scan_period_min;
next_scan = now + msecs_to_jiffies(p->numa_scan_period);
if (cmpxchg(&mm->numa_next_scan, migrate, next_scan) != migrate)
return;
/*
* Do not set pte_numa if the current running node is rate-limited.
* This loses statistics on the fault but if we are unwilling to
* migrate to this node, it is less likely we can do useful work
*/
if (migrate_ratelimited(numa_node_id()))
return;
start = mm->numa_scan_offset;
pages = sysctl_numa_balancing_scan_size;
pages <<= 20 - PAGE_SHIFT; /* MB in pages */
if (!pages)
return;
down_read(&mm->mmap_sem);
vma = find_vma(mm, start);
if (!vma) {
reset_ptenuma_scan(p);
start = 0;
vma = mm->mmap;
}
for (; vma; vma = vma->vm_next) {
if (!vma_migratable(vma))
continue;
/* Skip small VMAs. They are not likely to be of relevance */
if (vma->vm_end - vma->vm_start < HPAGE_SIZE)
continue;
/*
* Skip inaccessible VMAs to avoid any confusion between
* PROT_NONE and NUMA hinting ptes
*/
if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
continue;
do {
start = max(start, vma->vm_start);
end = ALIGN(start + (pages << PAGE_SHIFT), HPAGE_SIZE);
end = min(end, vma->vm_end);
pages -= change_prot_numa(vma, start, end);
start = end;
if (pages <= 0)
goto out;
} while (end != vma->vm_end);
}
out:
/*
* It is possible to reach the end of the VMA list but the last few VMAs are
* not guaranteed to the vma_migratable. If they are not, we would find the
* !migratable VMA on the next scan but not reset the scanner to the start
* so check it now.
*/
if (vma)
mm->numa_scan_offset = start;
else
reset_ptenuma_scan(p);
up_read(&mm->mmap_sem);
}
/*
* Drive the periodic memory faults..
*/
void task_tick_numa(struct rq *rq, struct task_struct *curr)
{
struct callback_head *work = &curr->numa_work;
u64 period, now;
/*
* We don't care about NUMA placement if we don't have memory.
*/
if (!curr->mm || (curr->flags & PF_EXITING) || work->next != work)
return;
/*
* Using runtime rather than walltime has the dual advantage that
* we (mostly) drive the selection from busy threads and that the
* task needs to have done some actual work before we bother with
* NUMA placement.
*/
now = curr->se.sum_exec_runtime;
period = (u64)curr->numa_scan_period * NSEC_PER_MSEC;
if (now - curr->node_stamp > period) {
if (!curr->node_stamp)
curr->numa_scan_period = sysctl_numa_balancing_scan_period_min;
curr->node_stamp = now;
if (!time_before(jiffies, curr->mm->numa_next_scan)) {
init_task_work(work, task_numa_work); /* TODO: move this into sched_fork() */
task_work_add(curr, work, true);
}
}
}
#else
static void task_tick_numa(struct rq *rq, struct task_struct *curr)
{
}
#endif /* CONFIG_NUMA_BALANCING */
static void
account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
update_load_add(&cfs_rq->load, se->load.weight);
if (!parent_entity(se))
update_load_add(&rq_of(cfs_rq)->load, se->load.weight);
#ifdef CONFIG_SMP
if (entity_is_task(se))
list_add(&se->group_node, &rq_of(cfs_rq)->cfs_tasks);
#endif
cfs_rq->nr_running++;
}
static void
account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
update_load_sub(&cfs_rq->load, se->load.weight);
if (!parent_entity(se))
update_load_sub(&rq_of(cfs_rq)->load, se->load.weight);
if (entity_is_task(se))
list_del_init(&se->group_node);
cfs_rq->nr_running--;
}
#ifdef CONFIG_FAIR_GROUP_SCHED
# ifdef CONFIG_SMP
static inline long calc_tg_weight(struct task_group *tg, struct cfs_rq *cfs_rq)
{
long tg_weight;
/*
* Use this CPU's actual weight instead of the last load_contribution
* to gain a more accurate current total weight. See
* update_cfs_rq_load_contribution().
*/
tg_weight = atomic_long_read(&tg->load_avg);
tg_weight -= cfs_rq->tg_load_contrib;
tg_weight += cfs_rq->load.weight;
return tg_weight;
}
static long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg)
{
long tg_weight, load, shares;
tg_weight = calc_tg_weight(tg, cfs_rq);
load = cfs_rq->load.weight;
shares = (tg->shares * load);
if (tg_weight)
shares /= tg_weight;
if (shares < MIN_SHARES)
shares = MIN_SHARES;
if (shares > tg->shares)
shares = tg->shares;
return shares;
}
# else /* CONFIG_SMP */
static inline long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg)
{
return tg->shares;
}
# endif /* CONFIG_SMP */
static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se,
unsigned long weight)
{
if (se->on_rq) {
/* commit outstanding execution time */
if (cfs_rq->curr == se)
update_curr(cfs_rq);
account_entity_dequeue(cfs_rq, se);
}
update_load_set(&se->load, weight);
if (se->on_rq)
account_entity_enqueue(cfs_rq, se);
}
static inline int throttled_hierarchy(struct cfs_rq *cfs_rq);
static void update_cfs_shares(struct cfs_rq *cfs_rq)
{
struct task_group *tg;
struct sched_entity *se;
long shares;
tg = cfs_rq->tg;
se = tg->se[cpu_of(rq_of(cfs_rq))];
if (!se || throttled_hierarchy(cfs_rq))
return;
#ifndef CONFIG_SMP
if (likely(se->load.weight == tg->shares))
return;
#endif
shares = calc_cfs_shares(cfs_rq, tg);
reweight_entity(cfs_rq_of(se), se, shares);
}
#else /* CONFIG_FAIR_GROUP_SCHED */
static inline void update_cfs_shares(struct cfs_rq *cfs_rq)
{
}
#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_SMP
/*
* We choose a half-life close to 1 scheduling period.
* Note: The tables below are dependent on this value.
*/
//#define LOAD_AVG_PERIOD 32
//#define LOAD_AVG_MAX 47742 /* maximum possible load avg */
//#define LOAD_AVG_MAX_N 345 /* number of full periods to produce LOAD_MAX_AVG */
/* Precomputed fixed inverse multiplies for multiplication by y^n */
static const u32 runnable_avg_yN_inv[] = {
0xffffffff, 0xfa83b2da, 0xf5257d14, 0xefe4b99a, 0xeac0c6e6, 0xe5b906e6,
0xe0ccdeeb, 0xdbfbb796, 0xd744fcc9, 0xd2a81d91, 0xce248c14, 0xc9b9bd85,
0xc5672a10, 0xc12c4cc9, 0xbd08a39e, 0xb8fbaf46, 0xb504f333, 0xb123f581,
0xad583ee9, 0xa9a15ab4, 0xa5fed6a9, 0xa2704302, 0x9ef5325f, 0x9b8d39b9,
0x9837f050, 0x94f4efa8, 0x91c3d373, 0x8ea4398a, 0x8b95c1e3, 0x88980e80,
0x85aac367, 0x82cd8698,
};
/*
* Precomputed \Sum y^k { 1<=k<=n }. These are floor(true_value) to prevent
* over-estimates when re-combining.
*/
static const u32 runnable_avg_yN_sum[] = {
0, 1002, 1982, 2941, 3880, 4798, 5697, 6576, 7437, 8279, 9103,
9909,10698,11470,12226,12966,13690,14398,15091,15769,16433,17082,
17718,18340,18949,19545,20128,20698,21256,21802,22336,22859,23371,
};
/*
* Approximate:
* val * y^n, where y^32 ~= 0.5 (~1 scheduling period)
*/
static __always_inline u64 decay_load(u64 val, u64 n)
{
unsigned int local_n;
if (!n)
return val;
else if (unlikely(n > LOAD_AVG_PERIOD * 63))
return 0;
/* after bounds checking we can collapse to 32-bit */
local_n = n;
/*
* As y^PERIOD = 1/2, we can combine
* y^n = 1/2^(n/PERIOD) * k^(n%PERIOD)
* With a look-up table which covers k^n (n<PERIOD)
*
* To achieve constant time decay_load.
*/
if (unlikely(local_n >= LOAD_AVG_PERIOD)) {
val >>= local_n / LOAD_AVG_PERIOD;
local_n %= LOAD_AVG_PERIOD;
}
val *= runnable_avg_yN_inv[local_n];
/* We don't use SRR here since we always want to round down. */
return val >> 32;
}
/*
* For updates fully spanning n periods, the contribution to runnable
* average will be: \Sum 1024*y^n
*
* We can compute this reasonably efficiently by combining:
* y^PERIOD = 1/2 with precomputed \Sum 1024*y^n {for n <PERIOD}
*/
static u32 __compute_runnable_contrib(u64 n)
{
u32 contrib = 0;
if (likely(n <= LOAD_AVG_PERIOD))
return runnable_avg_yN_sum[n];
else if (unlikely(n >= LOAD_AVG_MAX_N))
return LOAD_AVG_MAX;
/* Compute \Sum k^n combining precomputed values for k^i, \Sum k^j */
do {
contrib /= 2; /* y^LOAD_AVG_PERIOD = 1/2 */
contrib += runnable_avg_yN_sum[LOAD_AVG_PERIOD];
n -= LOAD_AVG_PERIOD;
} while (n > LOAD_AVG_PERIOD);
contrib = decay_load(contrib, n);
return contrib + runnable_avg_yN_sum[n];
}
#ifdef CONFIG_HMP_VARIABLE_SCALE
#define HMP_VARIABLE_SCALE_SHIFT 16ULL
struct hmp_global_attr {
struct attribute attr;
ssize_t (*show)(struct kobject *kobj,
struct attribute *attr, char *buf);
ssize_t (*store)(struct kobject *a, struct attribute *b,
const char *c, size_t count);
int *value;
int (*to_sysfs)(int);
int (*from_sysfs)(int);
};
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
#define HMP_DATA_SYSFS_MAX 5
#else
#define HMP_DATA_SYSFS_MAX 4
#endif
struct hmp_data_struct {
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
int freqinvar_load_scale_enabled;
#endif
int multiplier; /* used to scale the time delta */
struct attribute_group attr_group;
struct attribute *attributes[HMP_DATA_SYSFS_MAX + 1];
struct hmp_global_attr attr[HMP_DATA_SYSFS_MAX];
} hmp_data;
static u64 hmp_variable_scale_convert(u64 delta);
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
/* Frequency-Invariant Load Modification:
* Loads are calculated as in PJT's patch however we also scale the current
* contribution in line with the frequency of the CPU that the task was
* executed on.
* In this version, we use a simple linear scale derived from the maximum
* frequency reported by CPUFreq. As an example:
*
* Consider that we ran a task for 100% of the previous interval.
*
* Our CPU was under asynchronous frequency control through one of the
* CPUFreq governors.
*
* The CPUFreq governor reports that it is able to scale the CPU between
* 500MHz and 1GHz.
*
* During the period, the CPU was running at 1GHz.
*
* In this case, our load contribution for that period is calculated as
* 1 * (number_of_active_microseconds)
*
* This results in our task being able to accumulate maximum load as normal.
*
*
* Consider now that our CPU was executing at 500MHz.
*
* We now scale the load contribution such that it is calculated as
* 0.5 * (number_of_active_microseconds)
*
* Our task can only record 50% maximum load during this period.
*
* This represents the task consuming 50% of the CPU's *possible* compute
* capacity. However the task did consume 100% of the CPU's *available*
* compute capacity which is the value seen by the CPUFreq governor and
* user-side CPU Utilization tools.
*
* Restricting tracked load to be scaled by the CPU's frequency accurately
* represents the consumption of possible compute capacity and allows the
* HMP migration's simple threshold migration strategy to interact more
* predictably with CPUFreq's asynchronous compute capacity changes.
*/
#define SCHED_FREQSCALE_SHIFT 10
struct cpufreq_extents {
u32 curr_scale;
u32 min;
u32 max;
u32 flags;
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
u32 const_max;
u32 throttling;
#endif
};
/* Flag set when the governor in use only allows one frequency.
* Disables scaling.
*/
#define SCHED_LOAD_FREQINVAR_SINGLEFREQ 0x01
static struct cpufreq_extents freq_scale[CONFIG_NR_CPUS];
#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
#endif /* CONFIG_HMP_VARIABLE_SCALE */
#ifdef CONFIG_MTK_SCHED_CMP
int get_cluster_id(unsigned int cpu)
{
return arch_get_cluster_id(cpu);
}
void get_cluster_cpus(struct cpumask *cpus, int cluster_id,
bool exclusive_offline)
{
struct cpumask cls_cpus;
arch_get_cluster_cpus(&cls_cpus, cluster_id);
if (exclusive_offline) {
cpumask_and(cpus, cpu_online_mask, &cls_cpus);
} else
cpumask_copy(cpus, &cls_cpus);
}
static int nr_cpus_in_cluster(int cluster_id, bool exclusive_offline)
{
struct cpumask cls_cpus;
int nr_cpus;
arch_get_cluster_cpus(&cls_cpus, cluster_id);
if (exclusive_offline) {
struct cpumask online_cpus;
cpumask_and(&online_cpus, cpu_online_mask, &cls_cpus);
nr_cpus = cpumask_weight(&online_cpus);
} else
nr_cpus = cpumask_weight(&cls_cpus);
return nr_cpus;
}
#endif /* CONFIG_MTK_SCHED_CMP */
void sched_get_big_little_cpus(struct cpumask *big, struct cpumask *little)
{
arch_get_big_little_cpus(big, little);
}
EXPORT_SYMBOL(sched_get_big_little_cpus);
/*
* generic entry point for cpu mask construction, dedicated for
* mediatek scheduler.
*/
static __init __inline void cmp_cputopo_domain_setup(void)
{
WARN(smp_processor_id() != 0, "%s is supposed runs on CPU0 "
"while kernel init", __func__);
#ifdef CONFIG_MTK_CPU_TOPOLOGY
/*
* sched_init
* |-> cmp_cputopo_domain_seutp()
* ...
* rest_init
* ^ fork kernel_init
* |-> kernel_init_freeable
* ...
* |-> arch_build_cpu_topology_domain
*
* here, we focus to build up cpu topology and domain before scheduler runs.
*/
pr_debug("[CPUTOPO][%s] build CPU topology and cluster.\n", __func__);
arch_build_cpu_topology_domain();
#endif
}
#ifdef CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY
static u64 __inline variable_scale_convert(u64 delta)
{
u64 high = delta >> 32ULL;
u64 low = delta & 0xffffffffULL;
low *= LOAD_AVG_VARIABLE_PERIOD;
high *= LOAD_AVG_VARIABLE_PERIOD;
return (low >> 16ULL) + (high << (32ULL - 16ULL));
}
#endif
/* We can represent the historical contribution to runnable average as the
* coefficients of a geometric series. To do this we sub-divide our runnable
* history into segments of approximately 1ms (1024us); label the segment that
* occurred N-ms ago p_N, with p_0 corresponding to the current period, e.g.
*
* [<- 1024us ->|<- 1024us ->|<- 1024us ->| ...
* p0 p1 p2
* (now) (~1ms ago) (~2ms ago)
*
* Let u_i denote the fraction of p_i that the entity was runnable.
*
* We then designate the fractions u_i as our co-efficients, yielding the
* following representation of historical load:
* u_0 + u_1*y + u_2*y^2 + u_3*y^3 + ...
*
* We choose y based on the with of a reasonably scheduling period, fixing:
* y^32 = 0.5
*
* This means that the contribution to load ~32ms ago (u_32) will be weighted
* approximately half as much as the contribution to load within the last ms
* (u_0).
*
* When a period "rolls over" and we have new u_0`, multiplying the previous
* sum again by y is sufficient to update:
* load_avg = u_0` + y*(u_0 + u_1*y + u_2*y^2 + ... )
* = u_0 + u_1*y + u_2*y^2 + ... [re-labeling u_i --> u_{i+1}]
*/
static __always_inline int __update_entity_runnable_avg(u64 now,
struct sched_avg *sa,
int runnable,
int running,
int cpu)
{
u64 delta, periods, lru;
u32 runnable_contrib;
int delta_w, decayed = 0;
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
u64 scaled_delta;
u32 scaled_runnable_contrib;
int scaled_delta_w;
u32 curr_scale = 1024;
#elif defined(CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY)
u64 scaled_delta;
u32 scaled_runnable_contrib;
int scaled_delta_w;
u32 curr_scale = CPUPOWER_FREQSCALE_DEFAULT;
#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
delta = now - sa->last_runnable_update;
lru = sa->last_runnable_update;
/*
* This should only happen when time goes backwards, which it
* unfortunately does during sched clock init when we swap over to TSC.
*/
if ((s64)delta < 0) {
sa->last_runnable_update = now;
return 0;
}
#ifdef CONFIG_HMP_VARIABLE_SCALE
delta = hmp_variable_scale_convert(delta);
#elif defined(CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY)
delta = variable_scale_convert(delta);
#endif
/*
* Use 1024ns as the unit of measurement since it's a reasonable
* approximation of 1us and fast to compute.
*/
delta >>= 10;
if (!delta)
return 0;
sa->last_runnable_update = now;
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
WARN(cpu < 0, "[%s] CPU %d < 0 !!!\n", __func__, cpu);
/* retrieve scale factor for load */
if (cpu >= 0 && cpu < nr_cpu_ids && hmp_data.freqinvar_load_scale_enabled)
curr_scale = freq_scale[cpu].curr_scale;
mt_sched_printf("[%s] cpu=%d delta=%llu now=%llu last=%llu curr_scale=%u",
__func__, cpu, delta, now, lru, curr_scale);
#elif defined(CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY)
WARN(cpu < 0, "[%s] CPU %d < 0 !!!\n", __func__, cpu);
/* retrieve scale factor for load */
if (cpu >= 0 && cpu < nr_cpu_ids)
curr_scale = (topology_cpu_capacity(cpu) << CPUPOWER_FREQSCALE_SHIFT)
/ (topology_max_cpu_capacity(cpu)+1);
mt_sched_printf("[%s] cpu=%d delta=%llu now=%llu last=%llu curr_scale=%u",
__func__, cpu, delta, now, lru, curr_scale);
#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
/* delta_w is the amount already accumulated against our next period */
delta_w = sa->runnable_avg_period % 1024;
if (delta + delta_w >= 1024) {
/* period roll-over */
decayed = 1;
/*
* Now that we know we're crossing a period boundary, figure
* out how much from delta we need to complete the current
* period and accrue it.
*/
delta_w = 1024 - delta_w;
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
/* scale runnable time if necessary */
scaled_delta_w = (delta_w * curr_scale)
>> SCHED_FREQSCALE_SHIFT;
if (runnable)
sa->runnable_avg_sum += scaled_delta_w;
if (running)
sa->usage_avg_sum += scaled_delta_w;
#elif defined(CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY)
/* scale runnable time if necessary */
scaled_delta_w = (delta_w * curr_scale)
>> CPUPOWER_FREQSCALE_SHIFT;
if (runnable)
sa->runnable_avg_sum += scaled_delta_w;
if (running)
sa->usage_avg_sum += scaled_delta_w;
#else
if (runnable)
sa->runnable_avg_sum += delta_w;
if (running)
sa->usage_avg_sum += delta_w;
#endif /* #ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
sa->runnable_avg_period += delta_w;
delta -= delta_w;
/* Figure out how many additional periods this update spans */
periods = delta / 1024;
delta %= 1024;
/* decay the load we have accumulated so far */
sa->runnable_avg_sum = decay_load(sa->runnable_avg_sum,
periods + 1);
sa->runnable_avg_period = decay_load(sa->runnable_avg_period,
periods + 1);
sa->usage_avg_sum = decay_load(sa->usage_avg_sum, periods + 1);
/* add the contribution from this period */
/* Efficiently calculate \sum (1..n_period) 1024*y^i */
runnable_contrib = __compute_runnable_contrib(periods);
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
/* Apply load scaling if necessary.
* Note that multiplying the whole series is same as
* multiplying all terms
*/
scaled_runnable_contrib = (runnable_contrib * curr_scale)
>> SCHED_FREQSCALE_SHIFT;
if (runnable)
sa->runnable_avg_sum += scaled_runnable_contrib;
if (running)
sa->usage_avg_sum += scaled_runnable_contrib;
#elif defined(CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY)
/* Apply load scaling if necessary.
* Note that multiplying the whole series is same as
* multiplying all terms
*/
scaled_runnable_contrib = (runnable_contrib * curr_scale)
>> CPUPOWER_FREQSCALE_SHIFT;
if (runnable)
sa->runnable_avg_sum += scaled_runnable_contrib;
if (running)
sa->usage_avg_sum += scaled_runnable_contrib;
#else
if (runnable)
sa->runnable_avg_sum += runnable_contrib;
if (running)
sa->usage_avg_sum += runnable_contrib;
#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
sa->runnable_avg_period += runnable_contrib;
}
/* Remainder of delta accrued against u_0` */
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
/* scale if necessary */
scaled_delta = ((delta * curr_scale) >> SCHED_FREQSCALE_SHIFT);
if (runnable)
sa->runnable_avg_sum += scaled_delta;
if (running)
sa->usage_avg_sum += scaled_delta;
#elif defined(CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY)
/* scale if necessary */
scaled_delta = ((delta * curr_scale) >> CPUPOWER_FREQSCALE_SHIFT);
if (runnable)
sa->runnable_avg_sum += scaled_delta;
if (running)
sa->usage_avg_sum += scaled_delta;
#else
if (runnable)
sa->runnable_avg_sum += delta;
if (running)
sa->usage_avg_sum += delta;
#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
sa->runnable_avg_period += delta;
return decayed;
}
/* Synchronize an entity's decay with its parenting cfs_rq.*/
static inline u64 __synchronize_entity_decay(struct sched_entity *se)
{
struct cfs_rq *cfs_rq = cfs_rq_of(se);
u64 decays = atomic64_read(&cfs_rq->decay_counter);
decays -= se->avg.decay_count;
if (!decays)
return 0;
se->avg.load_avg_contrib = decay_load(se->avg.load_avg_contrib, decays);
se->avg.decay_count = 0;
return decays;
}
#ifdef CONFIG_FAIR_GROUP_SCHED
static inline void __update_cfs_rq_tg_load_contrib(struct cfs_rq *cfs_rq,
int force_update)
{
struct task_group *tg = cfs_rq->tg;
long tg_contrib;
tg_contrib = cfs_rq->runnable_load_avg + cfs_rq->blocked_load_avg;
tg_contrib -= cfs_rq->tg_load_contrib;
if (force_update || abs(tg_contrib) > cfs_rq->tg_load_contrib / 8) {
atomic_long_add(tg_contrib, &tg->load_avg);
cfs_rq->tg_load_contrib += tg_contrib;
}
}
/*
* Aggregate cfs_rq runnable averages into an equivalent task_group
* representation for computing load contributions.
*/
static inline void __update_tg_runnable_avg(struct sched_avg *sa,
struct cfs_rq *cfs_rq)
{
struct task_group *tg = cfs_rq->tg;
long contrib, usage_contrib;
/* The fraction of a cpu used by this cfs_rq */
contrib = div_u64(sa->runnable_avg_sum << NICE_0_SHIFT,
sa->runnable_avg_period + 1);
contrib -= cfs_rq->tg_runnable_contrib;
usage_contrib = div_u64(sa->usage_avg_sum << NICE_0_SHIFT,
sa->runnable_avg_period + 1);
usage_contrib -= cfs_rq->tg_usage_contrib;
/*
* contrib/usage at this point represent deltas, only update if they
* are substantive.
*/
if ((abs(contrib) > cfs_rq->tg_runnable_contrib / 64) ||
(abs(usage_contrib) > cfs_rq->tg_usage_contrib / 64)) {
atomic_add(contrib, &tg->runnable_avg);
cfs_rq->tg_runnable_contrib += contrib;
atomic_add(usage_contrib, &tg->usage_avg);
cfs_rq->tg_usage_contrib += usage_contrib;
}
}
static inline void __update_group_entity_contrib(struct sched_entity *se)
{
struct cfs_rq *cfs_rq = group_cfs_rq(se);
struct task_group *tg = cfs_rq->tg;
int runnable_avg;
u64 contrib;
contrib = cfs_rq->tg_load_contrib * tg->shares;
se->avg.load_avg_contrib = div_u64(contrib,
atomic_long_read(&tg->load_avg) + 1);
/*
* For group entities we need to compute a correction term in the case
* that they are consuming <1 cpu so that we would contribute the same
* load as a task of equal weight.
*
* Explicitly co-ordinating this measurement would be expensive, but
* fortunately the sum of each cpus contribution forms a usable
* lower-bound on the true value.
*
* Consider the aggregate of 2 contributions. Either they are disjoint
* (and the sum represents true value) or they are disjoint and we are
* understating by the aggregate of their overlap.
*
* Extending this to N cpus, for a given overlap, the maximum amount we
* understand is then n_i(n_i+1)/2 * w_i where n_i is the number of
* cpus that overlap for this interval and w_i is the interval width.
*
* On a small machine; the first term is well-bounded which bounds the
* total error since w_i is a subset of the period. Whereas on a
* larger machine, while this first term can be larger, if w_i is the
* of consequential size guaranteed to see n_i*w_i quickly converge to
* our upper bound of 1-cpu.
*/
runnable_avg = atomic_read(&tg->runnable_avg);
if (runnable_avg < NICE_0_LOAD) {
se->avg.load_avg_contrib *= runnable_avg;
se->avg.load_avg_contrib >>= NICE_0_SHIFT;
}
}
#else
static inline void __update_cfs_rq_tg_load_contrib(struct cfs_rq *cfs_rq,
int force_update) {}
static inline void __update_tg_runnable_avg(struct sched_avg *sa,
struct cfs_rq *cfs_rq) {}
static inline void __update_group_entity_contrib(struct sched_entity *se) {}
#endif
static inline void __update_task_entity_contrib(struct sched_entity *se)
{
u32 contrib;
/* avoid overflowing a 32-bit type w/ SCHED_LOAD_SCALE */
contrib = se->avg.runnable_avg_sum * scale_load_down(se->load.weight);
contrib /= (se->avg.runnable_avg_period + 1);
se->avg.load_avg_contrib = scale_load(contrib);
}
/* Compute the current contribution to load_avg by se, return any delta */
static long __update_entity_load_avg_contrib(struct sched_entity *se)
{
long old_contrib = se->avg.load_avg_contrib;
if (entity_is_task(se)) {
__update_task_entity_contrib(se);
} else {
__update_tg_runnable_avg(&se->avg, group_cfs_rq(se));
__update_group_entity_contrib(se);
}
return se->avg.load_avg_contrib - old_contrib;
}
#if defined(CONFIG_MTK_SCHED_CMP) || defined(CONFIG_SCHED_HMP_ENHANCEMENT)
/* usage_avg_sum & load_avg_ratio are based on Linaro 12.11. */
static long __update_task_entity_ratio(struct sched_entity *se)
{
long old_ratio = se->avg.load_avg_ratio;
u32 ratio;
ratio = se->avg.runnable_avg_sum * scale_load_down(NICE_0_LOAD);
ratio /= (se->avg.runnable_avg_period + 1);
se->avg.load_avg_ratio = scale_load(ratio);
return se->avg.load_avg_ratio - old_ratio;
}
#else
static inline long __update_task_entity_ratio(struct sched_entity *se) { return 0; }
#endif
static inline void subtract_blocked_load_contrib(struct cfs_rq *cfs_rq,
long load_contrib)
{
if (likely(load_contrib < cfs_rq->blocked_load_avg))
cfs_rq->blocked_load_avg -= load_contrib;
else
cfs_rq->blocked_load_avg = 0;
}
#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
unsigned int hmp_up_prio = NICE_TO_PRIO(CONFIG_SCHED_HMP_PRIO_FILTER_VAL);
#endif
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
/* Schedule entity */
#define se_pid(se) ((se != NULL && entity_is_task(se))? \
container_of(se,struct task_struct,se)->pid:-1)
#define se_load(se) se->avg.load_avg_ratio
#define se_contrib(se) se->avg.load_avg_contrib
/* CPU related : load information */
#define cfs_pending_load(cpu) cpu_rq(cpu)->cfs.avg.pending_load
#define cfs_load(cpu) cpu_rq(cpu)->cfs.avg.load_avg_ratio
#define cfs_contrib(cpu) cpu_rq(cpu)->cfs.avg.load_avg_contrib
/* CPU related : the number of tasks */
#define cfs_nr_normal_prio(cpu) cpu_rq(cpu)->cfs.avg.nr_normal_prio
#define cfs_nr_pending(cpu) cpu_rq(cpu)->cfs.avg.nr_pending
#define cfs_length(cpu) cpu_rq(cpu)->cfs.h_nr_running
#define rq_length(cpu) (cpu_rq(cpu)->nr_running + cfs_nr_pending(cpu))
#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
#define task_low_priority(prio) ((prio >= hmp_up_prio)?1:0)
#define cfs_nr_dequeuing_low_prio(cpu) \
cpu_rq(cpu)->cfs.avg.nr_dequeuing_low_prio
#define cfs_reset_nr_dequeuing_low_prio(cpu) \
(cfs_nr_dequeuing_low_prio(cpu) = 0)
#else
#define task_low_priority(prio) (0)
#define cfs_reset_nr_dequeuing_low_prio(cpu)
#endif /* CONFIG_SCHED_HMP_PRIO_FILTER */
#endif /* CONFIG_SCHED_HMP_ENHANCEMENT */
static inline u64 cfs_rq_clock_task(struct cfs_rq *cfs_rq);
#ifdef CONFIG_MTK_SCHED_CMP_TGS
int group_leader_is_empty(struct task_struct *p) {
struct task_struct *tg = p->group_leader;
if (SIGNAL_GROUP_EXIT & p->signal->flags){
// pr_warn("[%s] (0x%p/0x%p)(#%d/%s) leader: pid(%d) state(%d) exit_state(%d)signal_flags=%x p->signal->flags=%x group_exit_code=%x\n", __func__,
// p, tg, get_nr_threads(p), thread_group_empty(p) ? "empty" : "not empty",
// p->tgid, tg->state, tg->exit_state, tg->state, p->signal->flags, p->signal->group_exit_code);
return 1;
}
// workaround debug codes
if(tg->state == 0x6b6b6b6b){
// pr_warn("[%s] (0x%p/0x%p)(#%d/%s) leader: state(%d) exit_state(%d)\n", __func__,
// p, tg, get_nr_threads(p), thread_group_empty(p) ? "empty" : "not empty",
// tg->state, tg->exit_state);
return 1;
}
return 0;
}
static inline void update_tg_info(struct cfs_rq *cfs_rq, struct sched_entity *se, long ratio_delta)
{
struct task_struct *p = task_of(se);
struct task_struct *tg = p->group_leader;
int id;
unsigned long flags;
if (group_leader_is_empty(p))
return;
id = get_cluster_id(cfs_rq->rq->cpu);
if (unlikely(WARN_ON(id < 0)))
return;
raw_spin_lock_irqsave(&tg->thread_group_info_lock, flags);
tg->thread_group_info[id].load_avg_ratio += ratio_delta;
raw_spin_unlock_irqrestore(&tg->thread_group_info_lock, flags);
#ifdef CONFIG_MT_SCHED_INFO
mt_sched_printf("update_tg_info %d:%s %d:%s %ld %ld %d %d %lu:%lu:%lu update",
tg->pid, tg->comm, p->pid, p->comm,
se->avg.load_avg_ratio, ratio_delta,
cfs_rq->rq->cpu, id,
tg->thread_group_info[id].nr_running,
tg->thread_group_info[id].cfs_nr_running,
tg->thread_group_info[id].load_avg_ratio);
/*
mt_sched_printf("update %d:%s %d:%s %ld %ld %d %d %lu %lu %lu, %lu %lu %lu",
tg->pid, tg->comm, p->pid, p->comm,
se->avg.load_avg_ratio, ratio_delta,
id, cfs_rq->rq->cpu,
tg->thread_group_info[0].nr_running,
tg->thread_group_info[0].cfs_nr_running,
tg->thread_group_info[0].load_avg_ratio,
tg->thread_group_info[1].nr_running,
tg->thread_group_info[1].cfs_nr_running,
tg->thread_group_info[1].load_avg_ratio);
*/
#endif
}
#endif
/* Update a sched_entity's runnable average */
static inline void update_entity_load_avg(struct sched_entity *se,
int update_cfs_rq)
{
struct cfs_rq *cfs_rq = cfs_rq_of(se);
long contrib_delta;
u64 now;
long ratio_delta = 0;
int cpu = -1; /* not used in normal case */
#if defined(CONFIG_HMP_FREQUENCY_INVARIANT_SCALE) \
|| defined(CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY)
cpu = cfs_rq->rq->cpu;
#endif
/*
* For a group entity we need to use their owned cfs_rq_clock_task() in
* case they are the parent of a throttled hierarchy.
*/
if (entity_is_task(se))
now = cfs_rq_clock_task(cfs_rq);
else
now = cfs_rq_clock_task(group_cfs_rq(se));
if (!__update_entity_runnable_avg(now, &se->avg, se->on_rq,
cfs_rq->curr == se, cpu)) {
#if 0
if (entity_is_task(se)) {
ratio_delta = __update_task_entity_ratio(se);
if (update_cfs_rq)
{
cpu = cfs_rq->rq->cpu;
cpu_rq(cpu)->cfs.avg.load_avg_ratio += ratio_delta;
#ifdef CONFIG_HMP_TRACER
trace_sched_cfs_load_update(task_of(se),se_load(se),ratio_delta, cpu);
#endif /* CONFIG_HMP_TRACER */
}
trace_sched_task_entity_avg(2, task_of(se), &se->avg);
#ifdef CONFIG_MTK_SCHED_CMP_TGS
if (se->on_rq) {
update_tg_info(cfs_rq, se, ratio_delta);
}
#endif
}
#endif
return;
}
contrib_delta = __update_entity_load_avg_contrib(se);
/* usage_avg_sum & load_avg_ratio are based on Linaro 12.11. */
if (entity_is_task(se)) {
ratio_delta = __update_task_entity_ratio(se);
/*
* ratio is re-estimated just for entity of task; as
* for contrib, mark tracer here for task entity while
* mining tg's at __update_group_entity_contrib().
*
* track running usage in passing.
*/
trace_sched_task_entity_avg(3, task_of(se), &se->avg);
}
if (!update_cfs_rq)
return;
if (se->on_rq) {
cfs_rq->runnable_load_avg += contrib_delta;
if (entity_is_task(se)) {
cpu = cfs_rq->rq->cpu;
cpu_rq(cpu)->cfs.avg.load_avg_ratio += ratio_delta;
cpu_rq(cpu)->cfs.avg.load_avg_contrib += contrib_delta;
#ifdef CONFIG_HMP_TRACER
trace_sched_cfs_load_update(task_of(se),se_load(se),ratio_delta,cpu);
#endif /* CONFIG_HMP_TRACER */
#ifdef CONFIG_MTK_SCHED_CMP_TGS
update_tg_info(cfs_rq, se, ratio_delta);
#endif
}
}
else
subtract_blocked_load_contrib(cfs_rq, -contrib_delta);
}
/*
* Decay the load contributed by all blocked children and account this so that
* their contribution may appropriately discounted when they wake up.
*/
static void update_cfs_rq_blocked_load(struct cfs_rq *cfs_rq, int force_update)
{
u64 now = cfs_rq_clock_task(cfs_rq) >> 20;
u64 decays;
decays = now - cfs_rq->last_decay;
if (!decays && !force_update)
return;
if (atomic_long_read(&cfs_rq->removed_load)) {
unsigned long removed_load;
removed_load = atomic_long_xchg(&cfs_rq->removed_load, 0);
subtract_blocked_load_contrib(cfs_rq, removed_load);
}
if (decays) {
cfs_rq->blocked_load_avg = decay_load(cfs_rq->blocked_load_avg,
decays);
atomic64_add(decays, &cfs_rq->decay_counter);
cfs_rq->last_decay = now;
}
__update_cfs_rq_tg_load_contrib(cfs_rq, force_update);
}
static inline void update_rq_runnable_avg(struct rq *rq, int runnable)
{
u32 contrib;
int cpu = -1; /* not used in normal case */
#if defined(CONFIG_HMP_FREQUENCY_INVARIANT_SCALE) \
|| defined(CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY)
cpu = rq->cpu;
#endif
__update_entity_runnable_avg(rq->clock_task, &rq->avg, runnable,
runnable, cpu);
__update_tg_runnable_avg(&rq->avg, &rq->cfs);
contrib = rq->avg.runnable_avg_sum * scale_load_down(1024);
contrib /= (rq->avg.runnable_avg_period + 1);
trace_sched_rq_runnable_ratio(cpu_of(rq), scale_load(contrib));
trace_sched_rq_runnable_load(cpu_of(rq), rq->cfs.runnable_load_avg);
}
/* Add the load generated by se into cfs_rq's child load-average */
static inline void enqueue_entity_load_avg(struct cfs_rq *cfs_rq,
struct sched_entity *se,
int wakeup)
{
int cpu = cfs_rq->rq->cpu;
/*
* We track migrations using entity decay_count <= 0, on a wake-up
* migration we use a negative decay count to track the remote decays
* accumulated while sleeping.
*
* Newly forked tasks are enqueued with se->avg.decay_count == 0, they
* are seen by enqueue_entity_load_avg() as a migration with an already
* constructed load_avg_contrib.
*/
if (unlikely(se->avg.decay_count <= 0)) {
se->avg.last_runnable_update = rq_of(cfs_rq)->clock_task;
if (se->avg.decay_count) {
/*
* In a wake-up migration we have to approximate the
* time sleeping. This is because we can't synchronize
* clock_task between the two cpus, and it is not
* guaranteed to be read-safe. Instead, we can
* approximate this using our carried decays, which are
* explicitly atomically readable.
*/
se->avg.last_runnable_update -= (-se->avg.decay_count)
<< 20;
update_entity_load_avg(se, 0);
/* Indicate that we're now synchronized and on-rq */
se->avg.decay_count = 0;
#ifdef CONFIG_MTK_SCHED_CMP
} else {
if (entity_is_task(se))
trace_sched_task_entity_avg(1, task_of(se), &se->avg);
#endif
}
wakeup = 0;
} else {
__synchronize_entity_decay(se);
}
/* migrated tasks did not contribute to our blocked load */
if (wakeup) {
subtract_blocked_load_contrib(cfs_rq, se->avg.load_avg_contrib);
update_entity_load_avg(se, 0);
}
cfs_rq->runnable_load_avg += se->avg.load_avg_contrib;
#ifdef CONFIG_MTK_SCHED_CMP_TGS
if(entity_is_task(se)){
update_tg_info(cfs_rq, se, se->avg.load_avg_ratio);
}
#endif
if (entity_is_task(se)) {
cpu_rq(cpu)->cfs.avg.load_avg_contrib += se->avg.load_avg_contrib;
cpu_rq(cpu)->cfs.avg.load_avg_ratio += se->avg.load_avg_ratio;
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
cfs_nr_pending(cpu) = 0;
cfs_pending_load(cpu) = 0;
#endif
#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
if(!task_low_priority(task_of(se)->prio))
cfs_nr_normal_prio(cpu)++;
#endif
#ifdef CONFIG_HMP_TRACER
trace_sched_cfs_enqueue_task(task_of(se),se_load(se),cpu);
#endif
}
/* we force update consideration on load-balancer moves */
update_cfs_rq_blocked_load(cfs_rq, !wakeup);
}
/*
* Remove se's load from this cfs_rq child load-average, if the entity is
* transitioning to a blocked state we track its projected decay using
* blocked_load_avg.
*/
static inline void dequeue_entity_load_avg(struct cfs_rq *cfs_rq,
struct sched_entity *se,
int sleep)
{
int cpu = cfs_rq->rq->cpu;
update_entity_load_avg(se, 1);
/* we force update consideration on load-balancer moves */
update_cfs_rq_blocked_load(cfs_rq, !sleep);
cfs_rq->runnable_load_avg -= se->avg.load_avg_contrib;
#ifdef CONFIG_MTK_SCHED_CMP_TGS
if(entity_is_task(se)){
update_tg_info(cfs_rq, se, -se->avg.load_avg_ratio);
}
#endif
if (entity_is_task(se)) {
cpu_rq(cpu)->cfs.avg.load_avg_contrib -= se->avg.load_avg_contrib;
cpu_rq(cpu)->cfs.avg.load_avg_ratio -= se->avg.load_avg_ratio;
#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
cfs_reset_nr_dequeuing_low_prio(cpu);
if(!task_low_priority(task_of(se)->prio))
cfs_nr_normal_prio(cpu)--;
#endif
#ifdef CONFIG_HMP_TRACER
trace_sched_cfs_dequeue_task(task_of(se),se_load(se),cpu);
#endif
}
if (sleep) {
cfs_rq->blocked_load_avg += se->avg.load_avg_contrib;
se->avg.decay_count = atomic64_read(&cfs_rq->decay_counter);
} /* migrations, e.g. sleep=0 leave decay_count == 0 */
}
/*
* Update the rq's load with the elapsed running time before entering
* idle. if the last scheduled task is not a CFS task, idle_enter will
* be the only way to update the runnable statistic.
*/
void idle_enter_fair(struct rq *this_rq)
{
update_rq_runnable_avg(this_rq, 1);
}
/*
* Update the rq's load with the elapsed idle time before a task is
* scheduled. if the newly scheduled task is not a CFS task, idle_exit will
* be the only way to update the runnable statistic.
*/
void idle_exit_fair(struct rq *this_rq)
{
update_rq_runnable_avg(this_rq, 0);
}
#else
static inline void update_entity_load_avg(struct sched_entity *se,
int update_cfs_rq) {}
static inline void update_rq_runnable_avg(struct rq *rq, int runnable) {}
static inline void enqueue_entity_load_avg(struct cfs_rq *cfs_rq,
struct sched_entity *se,
int wakeup) {}
static inline void dequeue_entity_load_avg(struct cfs_rq *cfs_rq,
struct sched_entity *se,
int sleep) {}
static inline void update_cfs_rq_blocked_load(struct cfs_rq *cfs_rq,
int force_update) {}
#endif
static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
#ifdef CONFIG_SCHEDSTATS
struct task_struct *tsk = NULL;
if (entity_is_task(se))
tsk = task_of(se);
if (se->statistics.sleep_start) {
u64 delta = rq_of(cfs_rq)->clock - se->statistics.sleep_start;
if ((s64)delta < 0)
delta = 0;
if (unlikely(delta > se->statistics.sleep_max))
se->statistics.sleep_max = delta;
se->statistics.sleep_start = 0;
se->statistics.sum_sleep_runtime += delta;
if (tsk) {
account_scheduler_latency(tsk, delta >> 10, 1);
trace_sched_stat_sleep(tsk, delta);
}
}
if (se->statistics.block_start) {
u64 delta = rq_of(cfs_rq)->clock - se->statistics.block_start;
if ((s64)delta < 0)
delta = 0;
if (unlikely(delta > se->statistics.block_max))
se->statistics.block_max = delta;
se->statistics.block_start = 0;
se->statistics.sum_sleep_runtime += delta;
if (tsk) {
if (tsk->in_iowait) {
se->statistics.iowait_sum += delta;
se->statistics.iowait_count++;
trace_sched_stat_iowait(tsk, delta);
}
trace_sched_stat_blocked(tsk, delta);
/*
* Blocking time is in units of nanosecs, so shift by
* 20 to get a milliseconds-range estimation of the
* amount of time that the task spent sleeping:
*/
if (unlikely(prof_on == SLEEP_PROFILING)) {
profile_hits(SLEEP_PROFILING,
(void *)get_wchan(tsk),
delta >> 20);
}
account_scheduler_latency(tsk, delta >> 10, 0);
}
}
#endif
}
static void check_spread(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
#ifdef CONFIG_SCHED_DEBUG
s64 d = se->vruntime - cfs_rq->min_vruntime;
if (d < 0)
d = -d;
if (d > 3*sysctl_sched_latency)
schedstat_inc(cfs_rq, nr_spread_over);
#endif
}
static void
place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
{
u64 vruntime = cfs_rq->min_vruntime;
/*
* The 'current' period is already promised to the current tasks,
* however the extra weight of the new task will slow them down a
* little, place the new task so that it fits in the slot that
* stays open at the end.
*/
if (initial && sched_feat(START_DEBIT))
vruntime += sched_vslice(cfs_rq, se);
/* sleeps up to a single latency don't count. */
if (!initial) {
unsigned long thresh = sysctl_sched_latency;
/*
* Halve their sleep time's effect, to allow
* for a gentler effect of sleepers:
*/
if (sched_feat(GENTLE_FAIR_SLEEPERS))
thresh >>= 1;
vruntime -= thresh;
}
/* ensure we never gain time by being placed backwards. */
se->vruntime = max_vruntime(se->vruntime, vruntime);
}
static void check_enqueue_throttle(struct cfs_rq *cfs_rq);
static void
enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
{
/*
* Update the normalized vruntime before updating min_vruntime
* through calling update_curr().
*/
if (!(flags & ENQUEUE_WAKEUP) || (flags & ENQUEUE_WAKING))
se->vruntime += cfs_rq->min_vruntime;
/*
* Update run-time statistics of the 'current'.
*/
update_curr(cfs_rq);
enqueue_entity_load_avg(cfs_rq, se, flags & ENQUEUE_WAKEUP);
account_entity_enqueue(cfs_rq, se);
update_cfs_shares(cfs_rq);
if (flags & ENQUEUE_WAKEUP) {
place_entity(cfs_rq, se, 0);
enqueue_sleeper(cfs_rq, se);
}
update_stats_enqueue(cfs_rq, se);
check_spread(cfs_rq, se);
if (se != cfs_rq->curr)
__enqueue_entity(cfs_rq, se);
se->on_rq = 1;
if (cfs_rq->nr_running == 1) {
list_add_leaf_cfs_rq(cfs_rq);
check_enqueue_throttle(cfs_rq);
}
}
static void __clear_buddies_last(struct sched_entity *se)
{
for_each_sched_entity(se) {
struct cfs_rq *cfs_rq = cfs_rq_of(se);
if (cfs_rq->last == se)
cfs_rq->last = NULL;
else
break;
}
}
static void __clear_buddies_next(struct sched_entity *se)
{
for_each_sched_entity(se) {
struct cfs_rq *cfs_rq = cfs_rq_of(se);
if (cfs_rq->next == se)
cfs_rq->next = NULL;
else
break;
}
}
static void __clear_buddies_skip(struct sched_entity *se)
{
for_each_sched_entity(se) {
struct cfs_rq *cfs_rq = cfs_rq_of(se);
if (cfs_rq->skip == se)
cfs_rq->skip = NULL;
else
break;
}
}
static void clear_buddies(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
if (cfs_rq->last == se)
__clear_buddies_last(se);
if (cfs_rq->next == se)
__clear_buddies_next(se);
if (cfs_rq->skip == se)
__clear_buddies_skip(se);
}
static __always_inline void return_cfs_rq_runtime(struct cfs_rq *cfs_rq);
static void
dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
{
/*
* Update run-time statistics of the 'current'.
*/
update_curr(cfs_rq);
dequeue_entity_load_avg(cfs_rq, se, flags & DEQUEUE_SLEEP);
update_stats_dequeue(cfs_rq, se);
if (flags & DEQUEUE_SLEEP) {
#ifdef CONFIG_SCHEDSTATS
if (entity_is_task(se)) {
struct task_struct *tsk = task_of(se);
if (tsk->state & TASK_INTERRUPTIBLE)
se->statistics.sleep_start = rq_of(cfs_rq)->clock;
if (tsk->state & TASK_UNINTERRUPTIBLE)
se->statistics.block_start = rq_of(cfs_rq)->clock;
}
#endif
}
clear_buddies(cfs_rq, se);
if (se != cfs_rq->curr)
__dequeue_entity(cfs_rq, se);
se->on_rq = 0;
account_entity_dequeue(cfs_rq, se);
/*
* Normalize the entity after updating the min_vruntime because the
* update can refer to the ->curr item and we need to reflect this
* movement in our normalized position.
*/
if (!(flags & DEQUEUE_SLEEP))
se->vruntime -= cfs_rq->min_vruntime;
/* return excess runtime on last dequeue */
return_cfs_rq_runtime(cfs_rq);
update_min_vruntime(cfs_rq);
update_cfs_shares(cfs_rq);
}
/*
* Preempt the current task with a newly woken task if needed:
*/
static void
check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
{
unsigned long ideal_runtime, delta_exec;
struct sched_entity *se;
s64 delta;
ideal_runtime = sched_slice(cfs_rq, curr);
delta_exec = curr->sum_exec_runtime - curr->prev_sum_exec_runtime;
if (delta_exec > ideal_runtime) {
resched_task(rq_of(cfs_rq)->curr);
/*
* The current task ran long enough, ensure it doesn't get
* re-elected due to buddy favours.
*/
clear_buddies(cfs_rq, curr);
return;
}
/*
* Ensure that a task that missed wakeup preemption by a
* narrow margin doesn't have to wait for a full slice.
* This also mitigates buddy induced latencies under load.
*/
if (delta_exec < sysctl_sched_min_granularity)
return;
se = __pick_first_entity(cfs_rq);
delta = curr->vruntime - se->vruntime;
if (delta < 0)
return;
if (delta > ideal_runtime)
resched_task(rq_of(cfs_rq)->curr);
}
static void
set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
/* 'current' is not kept within the tree. */
if (se->on_rq) {
/*
* Any task has to be enqueued before it get to execute on
* a CPU. So account for the time it spent waiting on the
* runqueue.
*/
update_stats_wait_end(cfs_rq, se);
__dequeue_entity(cfs_rq, se);
update_entity_load_avg(se, 1);
}
update_stats_curr_start(cfs_rq, se);
cfs_rq->curr = se;
#ifdef CONFIG_SCHEDSTATS
/*
* Track our maximum slice length, if the CPU's load is at
* least twice that of our own weight (i.e. dont track it
* when there are only lesser-weight tasks around):
*/
if (rq_of(cfs_rq)->load.weight >= 2*se->load.weight) {
se->statistics.slice_max = max(se->statistics.slice_max,
se->sum_exec_runtime - se->prev_sum_exec_runtime);
}
#endif
se->prev_sum_exec_runtime = se->sum_exec_runtime;
}
static int
wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se);
/*
* Pick the next process, keeping these things in mind, in this order:
* 1) keep things fair between processes/task groups
* 2) pick the "next" process, since someone really wants that to run
* 3) pick the "last" process, for cache locality
* 4) do not run the "skip" process, if something else is available
*/
static struct sched_entity *pick_next_entity(struct cfs_rq *cfs_rq)
{
struct sched_entity *se = __pick_first_entity(cfs_rq);
struct sched_entity *left = se;
/*
* Avoid running the skip buddy, if running something else can
* be done without getting too unfair.
*/
if (cfs_rq->skip == se) {
struct sched_entity *second = __pick_next_entity(se);
if (second && wakeup_preempt_entity(second, left) < 1)
se = second;
}
/*
* Prefer last buddy, try to return the CPU to a preempted task.
*/
if (cfs_rq->last && wakeup_preempt_entity(cfs_rq->last, left) < 1)
se = cfs_rq->last;
/*
* Someone really wants this to run. If it's not unfair, run it.
*/
if (cfs_rq->next && wakeup_preempt_entity(cfs_rq->next, left) < 1)
se = cfs_rq->next;
clear_buddies(cfs_rq, se);
return se;
}
static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq);
static void put_prev_entity(struct cfs_rq *cfs_rq, struct sched_entity *prev)
{
/*
* If still on the runqueue then deactivate_task()
* was not called and update_curr() has to be done:
*/
if (prev->on_rq)
update_curr(cfs_rq);
/* throttle cfs_rqs exceeding runtime */
check_cfs_rq_runtime(cfs_rq);
check_spread(cfs_rq, prev);
if (prev->on_rq) {
update_stats_wait_start(cfs_rq, prev);
/* Put 'current' back into the tree. */
__enqueue_entity(cfs_rq, prev);
/* in !on_rq case, update occurred at dequeue */
update_entity_load_avg(prev, 1);
}
cfs_rq->curr = NULL;
}
static void
entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
{
/*
* Update run-time statistics of the 'current'.
*/
update_curr(cfs_rq);
/*
* Ensure that runnable average is periodically updated.
*/
update_entity_load_avg(curr, 1);
update_cfs_rq_blocked_load(cfs_rq, 1);
update_cfs_shares(cfs_rq);
#ifdef CONFIG_SCHED_HRTICK
/*
* queued ticks are scheduled to match the slice, so don't bother
* validating it and just reschedule.
*/
if (queued) {
resched_task(rq_of(cfs_rq)->curr);
return;
}
/*
* don't let the period tick interfere with the hrtick preemption
*/
if (!sched_feat(DOUBLE_TICK) &&
hrtimer_active(&rq_of(cfs_rq)->hrtick_timer))
return;
#endif
if (cfs_rq->nr_running > 1)
check_preempt_tick(cfs_rq, curr);
}
/**************************************************
* CFS bandwidth control machinery
*/
#ifdef CONFIG_CFS_BANDWIDTH
#ifdef HAVE_JUMP_LABEL
static struct static_key __cfs_bandwidth_used;
static inline bool cfs_bandwidth_used(void)
{
return static_key_false(&__cfs_bandwidth_used);
}
void cfs_bandwidth_usage_inc(void)
{
static_key_slow_inc(&__cfs_bandwidth_used);
}
void cfs_bandwidth_usage_dec(void)
{
static_key_slow_dec(&__cfs_bandwidth_used);
}
#else /* HAVE_JUMP_LABEL */
static bool cfs_bandwidth_used(void)
{
return true;
}
void cfs_bandwidth_usage_inc(void) {}
void cfs_bandwidth_usage_dec(void) {}
#endif /* HAVE_JUMP_LABEL */
/*
* default period for cfs group bandwidth.
* default: 0.1s, units: nanoseconds
*/
static inline u64 default_cfs_period(void)
{
return 100000000ULL;
}
static inline u64 sched_cfs_bandwidth_slice(void)
{
return (u64)sysctl_sched_cfs_bandwidth_slice * NSEC_PER_USEC;
}
/*
* Replenish runtime according to assigned quota and update expiration time.
* We use sched_clock_cpu directly instead of rq->clock to avoid adding
* additional synchronization around rq->lock.
*
* requires cfs_b->lock
*/
void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b)
{
u64 now;
if (cfs_b->quota == RUNTIME_INF)
return;
now = sched_clock_cpu(smp_processor_id());
cfs_b->runtime = cfs_b->quota;
cfs_b->runtime_expires = now + ktime_to_ns(cfs_b->period);
}
static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
{
return &tg->cfs_bandwidth;
}
/* rq->task_clock normalized against any time this cfs_rq has spent throttled */
static inline u64 cfs_rq_clock_task(struct cfs_rq *cfs_rq)
{
if (unlikely(cfs_rq->throttle_count))
return cfs_rq->throttled_clock_task;
return rq_of(cfs_rq)->clock_task - cfs_rq->throttled_clock_task_time;
}
/* returns 0 on failure to allocate runtime */
static int assign_cfs_rq_runtime(struct cfs_rq *cfs_rq)
{
struct task_group *tg = cfs_rq->tg;
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(tg);
u64 amount = 0, min_amount, expires;
/* note: this is a positive sum as runtime_remaining <= 0 */
min_amount = sched_cfs_bandwidth_slice() - cfs_rq->runtime_remaining;
raw_spin_lock(&cfs_b->lock);
if (cfs_b->quota == RUNTIME_INF)
amount = min_amount;
else {
/*
* If the bandwidth pool has become inactive, then at least one
* period must have elapsed since the last consumption.
* Refresh the global state and ensure bandwidth timer becomes
* active.
*/
if (!cfs_b->timer_active) {
__refill_cfs_bandwidth_runtime(cfs_b);
__start_cfs_bandwidth(cfs_b);
}
if (cfs_b->runtime > 0) {
amount = min(cfs_b->runtime, min_amount);
cfs_b->runtime -= amount;
cfs_b->idle = 0;
}
}
expires = cfs_b->runtime_expires;
raw_spin_unlock(&cfs_b->lock);
cfs_rq->runtime_remaining += amount;
/*
* we may have advanced our local expiration to account for allowed
* spread between our sched_clock and the one on which runtime was
* issued.
*/
if ((s64)(expires - cfs_rq->runtime_expires) > 0)
cfs_rq->runtime_expires = expires;
return cfs_rq->runtime_remaining > 0;
}
/*
* Note: This depends on the synchronization provided by sched_clock and the
* fact that rq->clock snapshots this value.
*/
static void expire_cfs_rq_runtime(struct cfs_rq *cfs_rq)
{
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
struct rq *rq = rq_of(cfs_rq);
/* if the deadline is ahead of our clock, nothing to do */
if (likely((s64)(rq->clock - cfs_rq->runtime_expires) < 0))
return;
if (cfs_rq->runtime_remaining < 0)
return;
/*
* If the local deadline has passed we have to consider the
* possibility that our sched_clock is 'fast' and the global deadline
* has not truly expired.
*
* Fortunately we can check determine whether this the case by checking
* whether the global deadline has advanced.
*/
if ((s64)(cfs_rq->runtime_expires - cfs_b->runtime_expires) >= 0) {
/* extend local deadline, drift is bounded above by 2 ticks */
cfs_rq->runtime_expires += TICK_NSEC;
} else {
/* global deadline is ahead, expiration has passed */
cfs_rq->runtime_remaining = 0;
}
}
static void __account_cfs_rq_runtime(struct cfs_rq *cfs_rq,
unsigned long delta_exec)
{
/* dock delta_exec before expiring quota (as it could span periods) */
cfs_rq->runtime_remaining -= delta_exec;
expire_cfs_rq_runtime(cfs_rq);
if (likely(cfs_rq->runtime_remaining > 0))
return;
/*
* if we're unable to extend our runtime we resched so that the active
* hierarchy can be throttled
*/
if (!assign_cfs_rq_runtime(cfs_rq) && likely(cfs_rq->curr))
resched_task(rq_of(cfs_rq)->curr);
}
static __always_inline
void account_cfs_rq_runtime(struct cfs_rq *cfs_rq, unsigned long delta_exec)
{
if (!cfs_bandwidth_used() || !cfs_rq->runtime_enabled)
return;
__account_cfs_rq_runtime(cfs_rq, delta_exec);
}
static inline int cfs_rq_throttled(struct cfs_rq *cfs_rq)
{
return cfs_bandwidth_used() && cfs_rq->throttled;
}
/* check whether cfs_rq, or any parent, is throttled */
static inline int throttled_hierarchy(struct cfs_rq *cfs_rq)
{
return cfs_bandwidth_used() && cfs_rq->throttle_count;
}
/*
* Ensure that neither of the group entities corresponding to src_cpu or
* dest_cpu are members of a throttled hierarchy when performing group
* load-balance operations.
*/
static inline int throttled_lb_pair(struct task_group *tg,
int src_cpu, int dest_cpu)
{
struct cfs_rq *src_cfs_rq, *dest_cfs_rq;
src_cfs_rq = tg->cfs_rq[src_cpu];
dest_cfs_rq = tg->cfs_rq[dest_cpu];
return throttled_hierarchy(src_cfs_rq) ||
throttled_hierarchy(dest_cfs_rq);
}
/* updated child weight may affect parent so we have to do this bottom up */
static int tg_unthrottle_up(struct task_group *tg, void *data)
{
struct rq *rq = data;
struct cfs_rq *cfs_rq = tg->cfs_rq[cpu_of(rq)];
cfs_rq->throttle_count--;
#ifdef CONFIG_SMP
if (!cfs_rq->throttle_count) {
/* adjust cfs_rq_clock_task() */
cfs_rq->throttled_clock_task_time += rq->clock_task -
cfs_rq->throttled_clock_task;
}
#endif
return 0;
}
static int tg_throttle_down(struct task_group *tg, void *data)
{
struct rq *rq = data;
struct cfs_rq *cfs_rq = tg->cfs_rq[cpu_of(rq)];
/* group is entering throttled state, stop time */
if (!cfs_rq->throttle_count)
cfs_rq->throttled_clock_task = rq->clock_task;
cfs_rq->throttle_count++;
return 0;
}
static void throttle_cfs_rq(struct cfs_rq *cfs_rq)
{
struct rq *rq = rq_of(cfs_rq);
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
struct sched_entity *se;
long task_delta, dequeue = 1;
se = cfs_rq->tg->se[cpu_of(rq_of(cfs_rq))];
/* freeze hierarchy runnable averages while throttled */
rcu_read_lock();
walk_tg_tree_from(cfs_rq->tg, tg_throttle_down, tg_nop, (void *)rq);
rcu_read_unlock();
task_delta = cfs_rq->h_nr_running;
for_each_sched_entity(se) {
struct cfs_rq *qcfs_rq = cfs_rq_of(se);
/* throttled entity or throttle-on-deactivate */
if (!se->on_rq)
break;
if (dequeue)
dequeue_entity(qcfs_rq, se, DEQUEUE_SLEEP);
qcfs_rq->h_nr_running -= task_delta;
if (qcfs_rq->load.weight)
dequeue = 0;
}
if (!se)
rq->nr_running -= task_delta;
cfs_rq->throttled = 1;
cfs_rq->throttled_clock = rq->clock;
raw_spin_lock(&cfs_b->lock);
list_add_tail_rcu(&cfs_rq->throttled_list, &cfs_b->throttled_cfs_rq);
if (!cfs_b->timer_active)
__start_cfs_bandwidth(cfs_b);
raw_spin_unlock(&cfs_b->lock);
}
void unthrottle_cfs_rq(struct cfs_rq *cfs_rq)
{
struct rq *rq = rq_of(cfs_rq);
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
struct sched_entity *se;
int enqueue = 1;
long task_delta;
se = cfs_rq->tg->se[cpu_of(rq)];
cfs_rq->throttled = 0;
raw_spin_lock(&cfs_b->lock);
cfs_b->throttled_time += rq->clock - cfs_rq->throttled_clock;
list_del_rcu(&cfs_rq->throttled_list);
raw_spin_unlock(&cfs_b->lock);
update_rq_clock(rq);
/* update hierarchical throttle state */
walk_tg_tree_from(cfs_rq->tg, tg_nop, tg_unthrottle_up, (void *)rq);
if (!cfs_rq->load.weight)
return;
task_delta = cfs_rq->h_nr_running;
for_each_sched_entity(se) {
if (se->on_rq)
enqueue = 0;
cfs_rq = cfs_rq_of(se);
if (enqueue)
enqueue_entity(cfs_rq, se, ENQUEUE_WAKEUP);
cfs_rq->h_nr_running += task_delta;
if (cfs_rq_throttled(cfs_rq))
break;
}
if (!se)
rq->nr_running += task_delta;
/* determine whether we need to wake up potentially idle cpu */
if (rq->curr == rq->idle && rq->cfs.nr_running)
resched_task(rq->curr);
}
static u64 distribute_cfs_runtime(struct cfs_bandwidth *cfs_b,
u64 remaining, u64 expires)
{
struct cfs_rq *cfs_rq;
u64 runtime = remaining;
rcu_read_lock();
list_for_each_entry_rcu(cfs_rq, &cfs_b->throttled_cfs_rq,
throttled_list) {
struct rq *rq = rq_of(cfs_rq);
raw_spin_lock(&rq->lock);
if (!cfs_rq_throttled(cfs_rq))
goto next;
runtime = -cfs_rq->runtime_remaining + 1;
if (runtime > remaining)
runtime = remaining;
remaining -= runtime;
cfs_rq->runtime_remaining += runtime;
cfs_rq->runtime_expires = expires;
/* we check whether we're throttled above */
if (cfs_rq->runtime_remaining > 0)
unthrottle_cfs_rq(cfs_rq);
next:
raw_spin_unlock(&rq->lock);
if (!remaining)
break;
}
rcu_read_unlock();
return remaining;
}
/*
* Responsible for refilling a task_group's bandwidth and unthrottling its
* cfs_rqs as appropriate. If there has been no activity within the last
* period the timer is deactivated until scheduling resumes; cfs_b->idle is
* used to track this state.
*/
static int do_sched_cfs_period_timer(struct cfs_bandwidth *cfs_b, int overrun)
{
u64 runtime, runtime_expires;
int idle = 1, throttled;
raw_spin_lock(&cfs_b->lock);
/* no need to continue the timer with no bandwidth constraint */
if (cfs_b->quota == RUNTIME_INF)
goto out_unlock;
throttled = !list_empty(&cfs_b->throttled_cfs_rq);
/* idle depends on !throttled (for the case of a large deficit) */
idle = cfs_b->idle && !throttled;
cfs_b->nr_periods += overrun;
/* if we're going inactive then everything else can be deferred */
if (idle)
goto out_unlock;
/*
* if we have relooped after returning idle once, we need to update our
* status as actually running, so that other cpus doing
* __start_cfs_bandwidth will stop trying to cancel us.
*/
cfs_b->timer_active = 1;
__refill_cfs_bandwidth_runtime(cfs_b);
if (!throttled) {
/* mark as potentially idle for the upcoming period */
cfs_b->idle = 1;
goto out_unlock;
}
/* account preceding periods in which throttling occurred */
cfs_b->nr_throttled += overrun;
/*
* There are throttled entities so we must first use the new bandwidth
* to unthrottle them before making it generally available. This
* ensures that all existing debts will be paid before a new cfs_rq is
* allowed to run.
*/
runtime = cfs_b->runtime;
runtime_expires = cfs_b->runtime_expires;
cfs_b->runtime = 0;
/*
* This check is repeated as we are holding onto the new bandwidth
* while we unthrottle. This can potentially race with an unthrottled
* group trying to acquire new bandwidth from the global pool.
*/
while (throttled && runtime > 0) {
raw_spin_unlock(&cfs_b->lock);
/* we can't nest cfs_b->lock while distributing bandwidth */
runtime = distribute_cfs_runtime(cfs_b, runtime,
runtime_expires);
raw_spin_lock(&cfs_b->lock);
throttled = !list_empty(&cfs_b->throttled_cfs_rq);
}
/* return (any) remaining runtime */
cfs_b->runtime = runtime;
/*
* While we are ensured activity in the period following an
* unthrottle, this also covers the case in which the new bandwidth is
* insufficient to cover the existing bandwidth deficit. (Forcing the
* timer to remain active while there are any throttled entities.)
*/
cfs_b->idle = 0;
out_unlock:
if (idle)
cfs_b->timer_active = 0;
raw_spin_unlock(&cfs_b->lock);
return idle;
}
/* a cfs_rq won't donate quota below this amount */
static const u64 min_cfs_rq_runtime = 1 * NSEC_PER_MSEC;
/* minimum remaining period time to redistribute slack quota */
static const u64 min_bandwidth_expiration = 2 * NSEC_PER_MSEC;
/* how long we wait to gather additional slack before distributing */
static const u64 cfs_bandwidth_slack_period = 5 * NSEC_PER_MSEC;
/*
* Are we near the end of the current quota period?
*
* Requires cfs_b->lock for hrtimer_expires_remaining to be safe against the
* hrtimer base being cleared by __hrtimer_start_range_ns. In the case of
* migrate_hrtimers, base is never cleared, so we are fine.
*/
static int runtime_refresh_within(struct cfs_bandwidth *cfs_b, u64 min_expire)
{
struct hrtimer *refresh_timer = &cfs_b->period_timer;
u64 remaining;
/* if the call-back is running a quota refresh is already occurring */
if (hrtimer_callback_running(refresh_timer))
return 1;
/* is a quota refresh about to occur? */
remaining = ktime_to_ns(hrtimer_expires_remaining(refresh_timer));
if (remaining < min_expire)
return 1;
return 0;
}
static void start_cfs_slack_bandwidth(struct cfs_bandwidth *cfs_b)
{
u64 min_left = cfs_bandwidth_slack_period + min_bandwidth_expiration;
/* if there's a quota refresh soon don't bother with slack */
if (runtime_refresh_within(cfs_b, min_left))
return;
start_bandwidth_timer(&cfs_b->slack_timer,
ns_to_ktime(cfs_bandwidth_slack_period));
}
/* we know any runtime found here is valid as update_curr() precedes return */
static void __return_cfs_rq_runtime(struct cfs_rq *cfs_rq)
{
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
s64 slack_runtime = cfs_rq->runtime_remaining - min_cfs_rq_runtime;
if (slack_runtime <= 0)
return;
raw_spin_lock(&cfs_b->lock);
if (cfs_b->quota != RUNTIME_INF &&
cfs_rq->runtime_expires == cfs_b->runtime_expires) {
cfs_b->runtime += slack_runtime;
/* we are under rq->lock, defer unthrottling using a timer */
if (cfs_b->runtime > sched_cfs_bandwidth_slice() &&
!list_empty(&cfs_b->throttled_cfs_rq))
start_cfs_slack_bandwidth(cfs_b);
}
raw_spin_unlock(&cfs_b->lock);
/* even if it's not valid for return we don't want to try again */
cfs_rq->runtime_remaining -= slack_runtime;
}
static __always_inline void return_cfs_rq_runtime(struct cfs_rq *cfs_rq)
{
if (!cfs_bandwidth_used())
return;
if (!cfs_rq->runtime_enabled || cfs_rq->nr_running)
return;
__return_cfs_rq_runtime(cfs_rq);
}
/*
* This is done with a timer (instead of inline with bandwidth return) since
* it's necessary to juggle rq->locks to unthrottle their respective cfs_rqs.
*/
static void do_sched_cfs_slack_timer(struct cfs_bandwidth *cfs_b)
{
u64 runtime = 0, slice = sched_cfs_bandwidth_slice();
u64 expires;
/* confirm we're still not at a refresh boundary */
raw_spin_lock(&cfs_b->lock);
if (runtime_refresh_within(cfs_b, min_bandwidth_expiration)) {
raw_spin_unlock(&cfs_b->lock);
return;
}
if (cfs_b->quota != RUNTIME_INF && cfs_b->runtime > slice) {
runtime = cfs_b->runtime;
cfs_b->runtime = 0;
}
expires = cfs_b->runtime_expires;
raw_spin_unlock(&cfs_b->lock);
if (!runtime)
return;
runtime = distribute_cfs_runtime(cfs_b, runtime, expires);
raw_spin_lock(&cfs_b->lock);
if (expires == cfs_b->runtime_expires)
cfs_b->runtime = runtime;
raw_spin_unlock(&cfs_b->lock);
}
/*
* When a group wakes up we want to make sure that its quota is not already
* expired/exceeded, otherwise it may be allowed to steal additional ticks of
* runtime as update_curr() throttling can not not trigger until it's on-rq.
*/
static void check_enqueue_throttle(struct cfs_rq *cfs_rq)
{
if (!cfs_bandwidth_used())
return;
/* an active group must be handled by the update_curr()->put() path */
if (!cfs_rq->runtime_enabled || cfs_rq->curr)
return;
/* ensure the group is not already throttled */
if (cfs_rq_throttled(cfs_rq))
return;
/* update runtime allocation */
account_cfs_rq_runtime(cfs_rq, 0);
if (cfs_rq->runtime_remaining <= 0)
throttle_cfs_rq(cfs_rq);
}
/* conditionally throttle active cfs_rq's from put_prev_entity() */
static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq)
{
if (!cfs_bandwidth_used())
return;
if (likely(!cfs_rq->runtime_enabled || cfs_rq->runtime_remaining > 0))
return;
/*
* it's possible for a throttled entity to be forced into a running
* state (e.g. set_curr_task), in this case we're finished.
*/
if (cfs_rq_throttled(cfs_rq))
return;
throttle_cfs_rq(cfs_rq);
}
static inline u64 default_cfs_period(void);
static int do_sched_cfs_period_timer(struct cfs_bandwidth *cfs_b, int overrun);
static void do_sched_cfs_slack_timer(struct cfs_bandwidth *cfs_b);
static enum hrtimer_restart sched_cfs_slack_timer(struct hrtimer *timer)
{
struct cfs_bandwidth *cfs_b =
container_of(timer, struct cfs_bandwidth, slack_timer);
do_sched_cfs_slack_timer(cfs_b);
return HRTIMER_NORESTART;
}
static enum hrtimer_restart sched_cfs_period_timer(struct hrtimer *timer)
{
struct cfs_bandwidth *cfs_b =
container_of(timer, struct cfs_bandwidth, period_timer);
ktime_t now;
int overrun;
int idle = 0;
for (;;) {
now = hrtimer_cb_get_time(timer);
overrun = hrtimer_forward(timer, now, cfs_b->period);
if (!overrun)
break;
idle = do_sched_cfs_period_timer(cfs_b, overrun);
}
return idle ? HRTIMER_NORESTART : HRTIMER_RESTART;
}
void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
{
raw_spin_lock_init(&cfs_b->lock);
cfs_b->runtime = 0;
cfs_b->quota = RUNTIME_INF;
cfs_b->period = ns_to_ktime(default_cfs_period());
INIT_LIST_HEAD(&cfs_b->throttled_cfs_rq);
hrtimer_init(&cfs_b->period_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
cfs_b->period_timer.function = sched_cfs_period_timer;
hrtimer_init(&cfs_b->slack_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
cfs_b->slack_timer.function = sched_cfs_slack_timer;
}
static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq)
{
cfs_rq->runtime_enabled = 0;
INIT_LIST_HEAD(&cfs_rq->throttled_list);
}
/* requires cfs_b->lock, may release to reprogram timer */
void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
{
/*
* The timer may be active because we're trying to set a new bandwidth
* period or because we're racing with the tear-down path
* (timer_active==0 becomes visible before the hrtimer call-back
* terminates). In either case we ensure that it's re-programmed
*/
while (unlikely(hrtimer_active(&cfs_b->period_timer)) &&
hrtimer_try_to_cancel(&cfs_b->period_timer) < 0) {
/* bounce the lock to allow do_sched_cfs_period_timer to run */
raw_spin_unlock(&cfs_b->lock);
cpu_relax();
raw_spin_lock(&cfs_b->lock);
/* if someone else restarted the timer then we're done */
if (cfs_b->timer_active)
return;
}
cfs_b->timer_active = 1;
start_bandwidth_timer(&cfs_b->period_timer, cfs_b->period);
}
static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
{
hrtimer_cancel(&cfs_b->period_timer);
hrtimer_cancel(&cfs_b->slack_timer);
}
static void __maybe_unused unthrottle_offline_cfs_rqs(struct rq *rq)
{
struct cfs_rq *cfs_rq;
for_each_leaf_cfs_rq(rq, cfs_rq) {
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
if (!cfs_rq->runtime_enabled)
continue;
/*
* clock_task is not advancing so we just need to make sure
* there's some valid quota amount
*/
cfs_rq->runtime_remaining = cfs_b->quota;
if (cfs_rq_throttled(cfs_rq))
unthrottle_cfs_rq(cfs_rq);
}
}
#else /* CONFIG_CFS_BANDWIDTH */
static inline u64 cfs_rq_clock_task(struct cfs_rq *cfs_rq)
{
return rq_of(cfs_rq)->clock_task;
}
static void account_cfs_rq_runtime(struct cfs_rq *cfs_rq,
unsigned long delta_exec) {}
static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq) {}
static void check_enqueue_throttle(struct cfs_rq *cfs_rq) {}
static __always_inline void return_cfs_rq_runtime(struct cfs_rq *cfs_rq) {}
static inline int cfs_rq_throttled(struct cfs_rq *cfs_rq)
{
return 0;
}
static inline int throttled_hierarchy(struct cfs_rq *cfs_rq)
{
return 0;
}
static inline int throttled_lb_pair(struct task_group *tg,
int src_cpu, int dest_cpu)
{
return 0;
}
void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
#ifdef CONFIG_FAIR_GROUP_SCHED
static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq) {}
#endif
static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
{
return NULL;
}
static inline void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
static inline void unthrottle_offline_cfs_rqs(struct rq *rq) {}
#endif /* CONFIG_CFS_BANDWIDTH */
/**************************************************
* CFS operations on tasks:
*/
#ifdef CONFIG_SCHED_HRTICK
static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
{
struct sched_entity *se = &p->se;
struct cfs_rq *cfs_rq = cfs_rq_of(se);
WARN_ON(task_rq(p) != rq);
if (cfs_rq->nr_running > 1) {
u64 slice = sched_slice(cfs_rq, se);
u64 ran = se->sum_exec_runtime - se->prev_sum_exec_runtime;
s64 delta = slice - ran;
if (delta < 0) {
if (rq->curr == p)
resched_task(p);
return;
}
/*
* Don't schedule slices shorter than 10000ns, that just
* doesn't make sense. Rely on vruntime for fairness.
*/
if (rq->curr != p)
delta = max_t(s64, 10000LL, delta);
hrtick_start(rq, delta);
}
}
/*
* called from enqueue/dequeue and updates the hrtick when the
* current task is from our class and nr_running is low enough
* to matter.
*/
static void hrtick_update(struct rq *rq)
{
struct task_struct *curr = rq->curr;
if (!hrtick_enabled(rq) || curr->sched_class != &fair_sched_class)
return;
if (cfs_rq_of(&curr->se)->nr_running < sched_nr_latency)
hrtick_start_fair(rq, curr);
}
#else /* !CONFIG_SCHED_HRTICK */
static inline void
hrtick_start_fair(struct rq *rq, struct task_struct *p)
{
}
static inline void hrtick_update(struct rq *rq)
{
}
#endif
#if defined(CONFIG_SCHED_HMP) || defined(CONFIG_MTK_SCHED_CMP)
/* CPU cluster statistics for task migration control */
#define HMP_GB (0x1000)
#define HMP_SELECT_RQ (0x2000)
#define HMP_LB (0x4000)
#define HMP_MAX_LOAD (NICE_0_LOAD - 1)
struct clb_env {
struct clb_stats bstats;
struct clb_stats lstats;
int btarget, ltarget;
struct cpumask *bcpus;
struct cpumask *lcpus;
unsigned int flags;
struct mcheck {
int status; /* Details of this migration check */
int result; /* Indicate whether we should perform this task migration */
} mcheck;
};
unsigned long __weak arch_scale_freq_power(struct sched_domain *sd, int cpu);
static void collect_cluster_stats(struct clb_stats *clbs,
struct cpumask *cluster_cpus, int target)
{
#define HMP_RESOLUTION_SCALING (4)
#define hmp_scale_down(w) ((w) >> HMP_RESOLUTION_SCALING)
/* Update cluster informatics */
int cpu;
for_each_cpu(cpu, cluster_cpus) {
if(cpu_online(cpu)) {
clbs->ncpu ++;
clbs->ntask += cpu_rq(cpu)->cfs.h_nr_running;
clbs->load_avg += cpu_rq(cpu)->cfs.avg.load_avg_ratio;
#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
clbs->nr_normal_prio_task += cfs_nr_normal_prio(cpu);
clbs->nr_dequeuing_low_prio += cfs_nr_dequeuing_low_prio(cpu);
#endif
}
}
if(!clbs->ncpu || NR_CPUS == target || !cpumask_test_cpu(target,cluster_cpus))
return;
clbs->cpu_power = (int) arch_scale_freq_power(NULL, target);
/* Scale current CPU compute capacity in accordance with frequency */
clbs->cpu_capacity = HMP_MAX_LOAD;
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
if (hmp_data.freqinvar_load_scale_enabled) {
cpu = cpumask_any(cluster_cpus);
if (freq_scale[cpu].throttling == 1){
clbs->cpu_capacity *= freq_scale[cpu].curr_scale;
}else {
clbs->cpu_capacity *= freq_scale[cpu].max;
}
clbs->cpu_capacity >>= SCHED_FREQSCALE_SHIFT;
if (clbs->cpu_capacity > HMP_MAX_LOAD){
clbs->cpu_capacity = HMP_MAX_LOAD;
}
}
#elif defined(CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY)
if (topology_cpu_inv_power_en()) {
cpu = cpumask_any(cluster_cpus);
if (topology_cpu_throttling(cpu))
clbs->cpu_capacity *=
(topology_cpu_capacity(cpu) << CPUPOWER_FREQSCALE_SHIFT)
/ (topology_max_cpu_capacity(cpu)+1);
else
clbs->cpu_capacity *= topology_max_cpu_capacity(cpu);
clbs->cpu_capacity >>= CPUPOWER_FREQSCALE_SHIFT;
if (clbs->cpu_capacity > HMP_MAX_LOAD){
clbs->cpu_capacity = HMP_MAX_LOAD;
}
}
#endif
/*
* Calculate available CPU capacity
* Calculate available task space
*
* Why load ratio should be multiplied by the number of task ?
* The task is the entity of scheduling unit so that we should consider
* it in scheduler. Only considering task load is not enough.
* Thus, multiplying the number of tasks can adjust load ratio to a more
* reasonable value.
*/
clbs->load_avg /= clbs->ncpu;
clbs->acap = clbs->cpu_capacity - cpu_rq(target)->cfs.avg.load_avg_ratio;
clbs->scaled_acap = hmp_scale_down(clbs->acap);
clbs->scaled_atask = cpu_rq(target)->cfs.h_nr_running * cpu_rq(target)->cfs.avg.load_avg_ratio;
clbs->scaled_atask = clbs->cpu_capacity - clbs->scaled_atask;
clbs->scaled_atask = hmp_scale_down(clbs->scaled_atask);
mt_sched_printf("[%s] cpu/cluster:%d/%02lx load/len:%lu/%u stats:%d,%d,%d,%d,%d,%d,%d,%d\n", __func__,
target, *cpumask_bits(cluster_cpus),
cpu_rq(target)->cfs.avg.load_avg_ratio, cpu_rq(target)->cfs.h_nr_running,
clbs->ncpu, clbs->ntask, clbs->load_avg, clbs->cpu_capacity,
clbs->acap, clbs->scaled_acap, clbs->scaled_atask, clbs->threshold);
}
//#define USE_HMP_DYNAMIC_THRESHOLD
#if defined(CONFIG_SCHED_HMP) && defined(USE_HMP_DYNAMIC_THRESHOLD)
static inline void hmp_dynamic_threshold(struct clb_env *clbenv);
#endif
/*
* Task Dynamic Migration Threshold Adjustment.
*
* If the workload between clusters is not balanced, adjust migration
* threshold in an attempt to move task precisely.
*
* Diff. = Max Threshold - Min Threshold
*
* Dynamic UP-Threshold =
* B_nacap B_natask
* Max Threshold - Diff. x ----------------- x -------------------
* B_nacap + L_nacap B_natask + L_natask
*
*
* Dynamic Down-Threshold =
* L_nacap L_natask
* Min Threshold + Diff. x ----------------- x -------------------
* B_nacap + L_nacap B_natask + L_natask
*/
static void adj_threshold(struct clb_env *clbenv)
{
#define TSKLD_SHIFT (2)
#define POSITIVE(x) ((int)(x) < 0 ? 0 : (x))
int bcpu, lcpu;
unsigned long b_cap=0, l_cap=0;
unsigned long b_load=0, l_load=0;
unsigned long b_task=0, l_task=0;
int b_nacap, l_nacap, b_natask, l_natask;
#if defined(CONFIG_SCHED_HMP) && defined(USE_HMP_DYNAMIC_THRESHOLD)
hmp_dynamic_threshold(clbenv);
return;
#endif
bcpu = clbenv->btarget;
lcpu = clbenv->ltarget;
if (bcpu < nr_cpu_ids) {
b_load = cpu_rq(bcpu)->cfs.avg.load_avg_ratio;
b_task = cpu_rq(bcpu)->cfs.h_nr_running;
}
if (lcpu < nr_cpu_ids) {
l_load = cpu_rq(lcpu)->cfs.avg.load_avg_ratio;
l_task = cpu_rq(lcpu)->cfs.h_nr_running;
}
#ifdef CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY
if (bcpu < nr_cpu_ids) {
b_cap = topology_cpu_capacity(bcpu);
}
if (lcpu < nr_cpu_ids) {
l_cap = topology_cpu_capacity(lcpu);
}
b_nacap = POSITIVE(b_cap - b_load);
b_natask = POSITIVE(b_cap - ((b_task * b_load) >> TSKLD_SHIFT));
l_nacap = POSITIVE(l_cap - l_load);
l_natask = POSITIVE(l_cap - ((l_task * l_load) >> TSKLD_SHIFT));
#else /* !CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY */
b_cap = clbenv->bstats.cpu_power;
l_cap = clbenv->lstats.cpu_power;
b_nacap = POSITIVE(clbenv->bstats.scaled_acap *
clbenv->bstats.cpu_power / (clbenv->lstats.cpu_power+1));
b_natask = POSITIVE(clbenv->bstats.scaled_atask *
clbenv->bstats.cpu_power / (clbenv->lstats.cpu_power+1));
l_nacap = POSITIVE(clbenv->lstats.scaled_acap);
l_natask = POSITIVE(clbenv->bstats.scaled_atask);
#endif /* CONFIG_ARCH_SCALE_INVARIANT_CPU_CAPACITY */
clbenv->bstats.threshold = HMP_MAX_LOAD - HMP_MAX_LOAD * b_nacap * b_natask /
((b_nacap + l_nacap) * (b_natask + l_natask)+1);
clbenv->lstats.threshold = HMP_MAX_LOAD * l_nacap * l_natask /
((b_nacap + l_nacap) * (b_natask + l_natask)+1);
mt_sched_printf("[%s]\tup/dl:%4d/%4d L(%d:%4lu,%4lu/%4lu) b(%d:%4lu,%4lu/%4lu)\n", __func__,
clbenv->bstats.threshold, clbenv->lstats.threshold,
lcpu, l_load, l_task, l_cap,
bcpu, b_load, b_task, b_cap);
}
static void sched_update_clbstats(struct clb_env *clbenv)
{
collect_cluster_stats(&clbenv->bstats, clbenv->bcpus, clbenv->btarget);
collect_cluster_stats(&clbenv->lstats, clbenv->lcpus, clbenv->ltarget);
adj_threshold(clbenv);
}
#endif /* #if defined(CONFIG_SCHED_HMP) || defined(CONFIG_SCHED_CMP) */
#ifdef CONFIG_SCHED_HMP
/*
* Heterogenous multiprocessor (HMP) optimizations
*
* The cpu types are distinguished using a list of hmp_domains
* which each represent one cpu type using a cpumask.
* The list is assumed ordered by compute capacity with the
* fastest domain first.
*/
DEFINE_PER_CPU(struct hmp_domain *, hmp_cpu_domain);
/* We need to know which cpus are fast and slow. */
extern struct cpumask hmp_fast_cpu_mask;
extern struct cpumask hmp_slow_cpu_mask;
extern void __init arch_get_hmp_domains(struct list_head *hmp_domains_list);
/* Setup hmp_domains */
static int __init hmp_cpu_mask_setup(void)
{
char buf[64];
struct hmp_domain *domain;
struct list_head *pos;
int dc, cpu;
#if defined(CONFIG_SCHED_HMP_ENHANCEMENT) || \
defined(CONFIG_MT_RT_SCHED) || defined(CONFIG_MT_RT_SCHED_LOG)
cpumask_clear(&hmp_fast_cpu_mask);
cpumask_clear(&hmp_slow_cpu_mask);
#endif
pr_debug("Initializing HMP scheduler:\n");
/* Initialize hmp_domains using platform code */
arch_get_hmp_domains(&hmp_domains);
if (list_empty(&hmp_domains)) {
pr_debug("HMP domain list is empty!\n");
return 0;
}
/* Print hmp_domains */
dc = 0;
list_for_each(pos, &hmp_domains) {
domain = list_entry(pos, struct hmp_domain, hmp_domains);
cpulist_scnprintf(buf, 64, &domain->possible_cpus);
pr_debug(" HMP domain %d: %s\n", dc, buf);
/*
* According to the description in "arch_get_hmp_domains",
* Fastest domain is at head of list. Thus, the fast-cpu mask should
* be initialized first, followed by slow-cpu mask.
*/
#if defined(CONFIG_SCHED_HMP_ENHANCEMENT) || \
defined(CONFIG_MT_RT_SCHED) || defined(CONFIG_MT_RT_SCHED_LOG)
if(cpumask_empty(&hmp_fast_cpu_mask)) {
cpumask_copy(&hmp_fast_cpu_mask,&domain->possible_cpus);
for_each_cpu(cpu, &hmp_fast_cpu_mask)
pr_debug(" HMP fast cpu : %d\n",cpu);
} else if (cpumask_empty(&hmp_slow_cpu_mask)){
cpumask_copy(&hmp_slow_cpu_mask,&domain->possible_cpus);
for_each_cpu(cpu, &hmp_slow_cpu_mask)
pr_debug(" HMP slow cpu : %d\n",cpu);
}
#endif
for_each_cpu_mask(cpu, domain->possible_cpus) {
per_cpu(hmp_cpu_domain, cpu) = domain;
}
dc++;
}
return 1;
}
static struct hmp_domain *hmp_get_hmp_domain_for_cpu(int cpu)
{
struct hmp_domain *domain;
struct list_head *pos;
list_for_each(pos, &hmp_domains) {
domain = list_entry(pos, struct hmp_domain, hmp_domains);
if(cpumask_test_cpu(cpu, &domain->possible_cpus))
return domain;
}
return NULL;
}
static void hmp_online_cpu(int cpu)
{
struct hmp_domain *domain = hmp_get_hmp_domain_for_cpu(cpu);
if(domain)
cpumask_set_cpu(cpu, &domain->cpus);
}
static void hmp_offline_cpu(int cpu)
{
struct hmp_domain *domain = hmp_get_hmp_domain_for_cpu(cpu);
if(domain)
cpumask_clear_cpu(cpu, &domain->cpus);
}
/*
* Migration thresholds should be in the range [0..1023]
* hmp_up_threshold: min. load required for migrating tasks to a faster cpu
* hmp_down_threshold: max. load allowed for tasks migrating to a slower cpu
* The default values (512, 256) offer good responsiveness, but may need
* tweaking suit particular needs.
*
* hmp_up_prio: Only up migrate task with high priority (<hmp_up_prio)
* hmp_next_up_threshold: Delay before next up migration (1024 ~= 1 ms)
* hmp_next_down_threshold: Delay before next down migration (1024 ~= 1 ms)
*/
#ifdef CONFIG_HMP_DYNAMIC_THRESHOLD
unsigned int hmp_up_threshold = 1023;
unsigned int hmp_down_threshold = 0;
#else
unsigned int hmp_up_threshold = 512;
unsigned int hmp_down_threshold = 256;
#endif
unsigned int hmp_next_up_threshold = 4096;
unsigned int hmp_next_down_threshold = 4096;
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
#define hmp_last_up_migration(cpu) \
cpu_rq(cpu)->cfs.avg.hmp_last_up_migration
#define hmp_last_down_migration(cpu) \
cpu_rq(cpu)->cfs.avg.hmp_last_down_migration
static int hmp_select_task_rq_fair(int sd_flag, struct task_struct *p,
int prev_cpu, int new_cpu);
#else
static unsigned int hmp_up_migration(int cpu, int *target_cpu, struct sched_entity *se);
static unsigned int hmp_down_migration(int cpu, struct sched_entity *se);
#endif
static inline unsigned int hmp_domain_min_load(struct hmp_domain *hmpd,
int *min_cpu);
/* Check if cpu is in fastest hmp_domain */
static inline unsigned int hmp_cpu_is_fastest(int cpu)
{
struct list_head *pos;
pos = &hmp_cpu_domain(cpu)->hmp_domains;
return pos == hmp_domains.next;
}
/* Check if cpu is in slowest hmp_domain */
static inline unsigned int hmp_cpu_is_slowest(int cpu)
{
struct list_head *pos;
pos = &hmp_cpu_domain(cpu)->hmp_domains;
return list_is_last(pos, &hmp_domains);
}
/* Next (slower) hmp_domain relative to cpu */
static inline struct hmp_domain *hmp_slower_domain(int cpu)
{
struct list_head *pos;
pos = &hmp_cpu_domain(cpu)->hmp_domains;
return list_entry(pos->next, struct hmp_domain, hmp_domains);
}
/* Previous (faster) hmp_domain relative to cpu */
static inline struct hmp_domain *hmp_faster_domain(int cpu)
{
struct list_head *pos;
pos = &hmp_cpu_domain(cpu)->hmp_domains;
return list_entry(pos->prev, struct hmp_domain, hmp_domains);
}
/*
* Selects a cpu in previous (faster) hmp_domain
* Note that cpumask_any_and() returns the first cpu in the cpumask
*/
static inline unsigned int hmp_select_faster_cpu(struct task_struct *tsk,
int cpu)
{
int lowest_cpu=NR_CPUS;
__always_unused int lowest_ratio = hmp_domain_min_load(hmp_faster_domain(cpu), &lowest_cpu);
/*
* If the lowest-loaded CPU in the domain is allowed by the task affinity
* select that one, otherwise select one which is allowed
*/
if(lowest_cpu < nr_cpu_ids && cpumask_test_cpu(lowest_cpu,tsk_cpus_allowed(tsk)))
return lowest_cpu;
else
return cpumask_any_and(&hmp_faster_domain(cpu)->cpus,
tsk_cpus_allowed(tsk));
}
/*
* Selects a cpu in next (slower) hmp_domain
* Note that cpumask_any_and() returns the first cpu in the cpumask
*/
static inline unsigned int hmp_select_slower_cpu(struct task_struct *tsk,
int cpu)
{
int lowest_cpu=NR_CPUS;
__always_unused int lowest_ratio = hmp_domain_min_load(hmp_slower_domain(cpu), &lowest_cpu);
/*
* If the lowest-loaded CPU in the domain is allowed by the task affinity
* select that one, otherwise select one which is allowed
*/
if(lowest_cpu < nr_cpu_ids && cpumask_test_cpu(lowest_cpu,tsk_cpus_allowed(tsk)))
return lowest_cpu;
else
return cpumask_any_and(&hmp_slower_domain(cpu)->cpus,
tsk_cpus_allowed(tsk));
}
static inline void hmp_next_up_delay(struct sched_entity *se, int cpu)
{
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
hmp_last_up_migration(cpu) = cfs_rq_clock_task(cfs_rq);
hmp_last_down_migration(cpu) = 0;
#else
struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
se->avg.hmp_last_up_migration = cfs_rq_clock_task(cfs_rq);
se->avg.hmp_last_down_migration = 0;
#endif
}
static inline void hmp_next_down_delay(struct sched_entity *se, int cpu)
{
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
hmp_last_down_migration(cpu) = cfs_rq_clock_task(cfs_rq);
hmp_last_up_migration(cpu) = 0;
#else
struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
se->avg.hmp_last_down_migration = cfs_rq_clock_task(cfs_rq);
se->avg.hmp_last_up_migration = 0;
#endif
}
#ifdef CONFIG_HMP_VARIABLE_SCALE
/*
* Heterogenous multiprocessor (HMP) optimizations
*
* These functions allow to change the growing speed of the load_avg_ratio
* by default it goes from 0 to 0.5 in LOAD_AVG_PERIOD = 32ms
* This can now be changed with /sys/kernel/hmp/load_avg_period_ms.
*
* These functions also allow to change the up and down threshold of HMP
* using /sys/kernel/hmp/{up,down}_threshold.
* Both must be between 0 and 1023. The threshold that is compared
* to the load_avg_ratio is up_threshold/1024 and down_threshold/1024.
*
* For instance, if load_avg_period = 64 and up_threshold = 512, an idle
* task with a load of 0 will reach the threshold after 64ms of busy loop.
*
* Changing load_avg_periods_ms has the same effect than changing the
* default scaling factor Y=1002/1024 in the load_avg_ratio computation to
* (1002/1024.0)^(LOAD_AVG_PERIOD/load_avg_period_ms), but the last one
* could trigger overflows.
* For instance, with Y = 1023/1024 in __update_task_entity_contrib()
* "contrib = se->avg.runnable_avg_sum * scale_load_down(se->load.weight);"
* could be overflowed for a weight > 2^12 even is the load_avg_contrib
* should still be a 32bits result. This would not happen by multiplicating
* delta time by 1/22 and setting load_avg_period_ms = 706.
*/
/*
* By scaling the delta time it end-up increasing or decrease the
* growing speed of the per entity load_avg_ratio
* The scale factor hmp_data.multiplier is a fixed point
* number: (32-HMP_VARIABLE_SCALE_SHIFT).HMP_VARIABLE_SCALE_SHIFT
*/
static u64 hmp_variable_scale_convert(u64 delta)
{
u64 high = delta >> 32ULL;
u64 low = delta & 0xffffffffULL;
low *= hmp_data.multiplier;
high *= hmp_data.multiplier;
return (low >> HMP_VARIABLE_SCALE_SHIFT)
+ (high << (32ULL - HMP_VARIABLE_SCALE_SHIFT));
}
static ssize_t hmp_show(struct kobject *kobj,
struct attribute *attr, char *buf)
{
ssize_t ret = 0;
struct hmp_global_attr *hmp_attr =
container_of(attr, struct hmp_global_attr, attr);
int temp = *(hmp_attr->value);
if (hmp_attr->to_sysfs != NULL)
temp = hmp_attr->to_sysfs(temp);
ret = sprintf(buf, "%d\n", temp);
return ret;
}
static ssize_t hmp_store(struct kobject *a, struct attribute *attr,
const char *buf, size_t count)
{
int temp;
ssize_t ret = count;
struct hmp_global_attr *hmp_attr =
container_of(attr, struct hmp_global_attr, attr);
char *str = vmalloc(count + 1);
if (str == NULL)
return -ENOMEM;
memcpy(str, buf, count);
str[count] = 0;
if (sscanf(str, "%d", &temp) < 1)
ret = -EINVAL;
else {
if (hmp_attr->from_sysfs != NULL)
temp = hmp_attr->from_sysfs(temp);
if (temp < 0)
ret = -EINVAL;
else
*(hmp_attr->value) = temp;
}
vfree(str);
return ret;
}
static int hmp_period_tofrom_sysfs(int value)
{
return (LOAD_AVG_PERIOD << HMP_VARIABLE_SCALE_SHIFT) / value;
}
/* max value for threshold is 1024 */
static int hmp_theshold_from_sysfs(int value)
{
if (value > 1024)
return -1;
return value;
}
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
/* freqinvar control is only 0,1 off/on */
static int hmp_freqinvar_from_sysfs(int value)
{
if (value < 0 || value > 1)
return -1;
return value;
}
#endif
static void hmp_attr_add(
const char *name,
int *value,
int (*to_sysfs)(int),
int (*from_sysfs)(int))
{
int i = 0;
while (hmp_data.attributes[i] != NULL) {
i++;
if (i >= HMP_DATA_SYSFS_MAX)
return;
}
hmp_data.attr[i].attr.mode = 0644;
hmp_data.attr[i].show = hmp_show;
hmp_data.attr[i].store = hmp_store;
hmp_data.attr[i].attr.name = name;
hmp_data.attr[i].value = value;
hmp_data.attr[i].to_sysfs = to_sysfs;
hmp_data.attr[i].from_sysfs = from_sysfs;
hmp_data.attributes[i] = &hmp_data.attr[i].attr;
hmp_data.attributes[i + 1] = NULL;
}
static int hmp_attr_init(void)
{
int ret;
memset(&hmp_data, sizeof(hmp_data), 0);
/* by default load_avg_period_ms == LOAD_AVG_PERIOD
* meaning no change
*/
/* LOAD_AVG_PERIOD is too short to trigger heavy task indicator
so we change it to LOAD_AVG_VARIABLE_PERIOD */
hmp_data.multiplier = hmp_period_tofrom_sysfs(LOAD_AVG_VARIABLE_PERIOD);
hmp_attr_add("load_avg_period_ms",
&hmp_data.multiplier,
hmp_period_tofrom_sysfs,
hmp_period_tofrom_sysfs);
hmp_attr_add("up_threshold",
&hmp_up_threshold,
NULL,
hmp_theshold_from_sysfs);
hmp_attr_add("down_threshold",
&hmp_down_threshold,
NULL,
hmp_theshold_from_sysfs);
hmp_attr_add("init_task_load_period",
&init_task_load_period,
NULL,
NULL);
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
/* default frequency-invariant scaling ON */
hmp_data.freqinvar_load_scale_enabled = 1;
hmp_attr_add("frequency_invariant_load_scale",
&hmp_data.freqinvar_load_scale_enabled,
NULL,
hmp_freqinvar_from_sysfs);
#endif
hmp_data.attr_group.name = "hmp";
hmp_data.attr_group.attrs = hmp_data.attributes;
ret = sysfs_create_group(kernel_kobj,
&hmp_data.attr_group);
return 0;
}
late_initcall(hmp_attr_init);
#endif /* CONFIG_HMP_VARIABLE_SCALE */
static inline unsigned int hmp_domain_min_load(struct hmp_domain *hmpd,
int *min_cpu)
{
int cpu;
int min_cpu_runnable_temp = NR_CPUS;
unsigned long min_runnable_load = INT_MAX;
unsigned long contrib;
for_each_cpu_mask(cpu, hmpd->cpus) {
/* don't use the divisor in the loop, just at the end */
contrib = cpu_rq(cpu)->avg.runnable_avg_sum * scale_load_down(1024);
if (contrib < min_runnable_load) {
min_runnable_load = contrib;
min_cpu_runnable_temp = cpu;
}
}
if (min_cpu)
*min_cpu = min_cpu_runnable_temp;
/* domain will often have at least one empty CPU */
return min_runnable_load ? min_runnable_load / (LOAD_AVG_MAX + 1) : 0;
}
/*
* Calculate the task starvation
* This is the ratio of actually running time vs. runnable time.
* If the two are equal the task is getting the cpu time it needs or
* it is alone on the cpu and the cpu is fully utilized.
*/
static inline unsigned int hmp_task_starvation(struct sched_entity *se)
{
u32 starvation;
starvation = se->avg.usage_avg_sum * scale_load_down(NICE_0_LOAD);
starvation /= (se->avg.runnable_avg_sum + 1);
return scale_load(starvation);
}
static inline unsigned int hmp_offload_down(int cpu, struct sched_entity *se)
{
int min_usage;
int dest_cpu = NR_CPUS;
if (hmp_cpu_is_slowest(cpu))
return NR_CPUS;
/* Is the current domain fully loaded? */
/* load < ~50% */
min_usage = hmp_domain_min_load(hmp_cpu_domain(cpu), NULL);
if (min_usage < (NICE_0_LOAD>>1))
return NR_CPUS;
/* Is the task alone on the cpu? */
if (cpu_rq(cpu)->cfs.nr_running < 2)
return NR_CPUS;
/* Is the task actually starving? */
/* >=25% ratio running/runnable = starving */
if (hmp_task_starvation(se) > 768)
return NR_CPUS;
/* Does the slower domain have spare cycles? */
min_usage = hmp_domain_min_load(hmp_slower_domain(cpu), &dest_cpu);
/* load > 50% */
if (min_usage > NICE_0_LOAD/2)
return NR_CPUS;
if (cpumask_test_cpu(dest_cpu, &hmp_slower_domain(cpu)->cpus))
return dest_cpu;
return NR_CPUS;
}
#endif /* CONFIG_SCHED_HMP */
#ifdef CONFIG_MTK_SCHED_CMP
/* Check if cpu is in fastest hmp_domain */
unsigned int cmp_up_threshold = 512;
unsigned int cmp_down_threshold = 256;
#endif /* CONFIG_MTK_SCHED_CMP */
#ifdef CONFIG_MTK_SCHED_CMP_TGS
static void sched_tg_enqueue_fair(struct rq *rq, struct task_struct *p)
{
int id;
unsigned long flags;
struct task_struct *tg = p->group_leader;
if (group_leader_is_empty(p))
return;
id = get_cluster_id(rq->cpu);
if (unlikely(WARN_ON(id < 0)))
return;
raw_spin_lock_irqsave(&tg->thread_group_info_lock, flags);
tg->thread_group_info[id].cfs_nr_running++;
raw_spin_unlock_irqrestore(&tg->thread_group_info_lock, flags);
}
static void sched_tg_dequeue_fair(struct rq *rq, struct task_struct *p)
{
int id;
unsigned long flags;
struct task_struct *tg = p->group_leader;
if (group_leader_is_empty(p))
return;
id = get_cluster_id(rq->cpu);
if (unlikely(WARN_ON(id < 0)))
return;
raw_spin_lock_irqsave(&tg->thread_group_info_lock, flags);
tg->thread_group_info[id].cfs_nr_running--;
raw_spin_unlock_irqrestore(&tg->thread_group_info_lock, flags);
}
#endif
/*
* The enqueue_task method is called before nr_running is
* increased. Here we update the fair scheduling stats and
* then put the task into the rbtree:
*/
static void
enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
{
struct cfs_rq *cfs_rq;
struct sched_entity *se = &p->se;
for_each_sched_entity(se) {
if (se->on_rq)
break;
cfs_rq = cfs_rq_of(se);
enqueue_entity(cfs_rq, se, flags);
/*
* end evaluation on encountering a throttled cfs_rq
*
* note: in the case of encountering a throttled cfs_rq we will
* post the final h_nr_running increment below.
*/
if (cfs_rq_throttled(cfs_rq))
break;
cfs_rq->h_nr_running++;
flags = ENQUEUE_WAKEUP;
}
for_each_sched_entity(se) {
cfs_rq = cfs_rq_of(se);
cfs_rq->h_nr_running++;
if (cfs_rq_throttled(cfs_rq))
break;
update_cfs_shares(cfs_rq);
update_entity_load_avg(se, 1);
}
if (!se) {
update_rq_runnable_avg(rq, rq->nr_running);
inc_nr_running(rq);
#ifndef CONFIG_CFS_BANDWIDTH
BUG_ON(rq->cfs.nr_running > rq->cfs.h_nr_running);
#endif
}
hrtick_update(rq);
#ifdef CONFIG_HMP_TRACER
trace_sched_runqueue_length(rq->cpu,rq->nr_running);
trace_sched_cfs_length(rq->cpu,rq->cfs.h_nr_running);
#endif
#ifdef CONFIG_MET_SCHED_HMP
RqLen(rq->cpu,rq->nr_running);
CfsLen(rq->cpu,rq->cfs.h_nr_running);
#endif
#ifdef CONFIG_MTK_SCHED_CMP_TGS
sched_tg_enqueue_fair(rq, p);
#endif
}
static void set_next_buddy(struct sched_entity *se);
/*
* The dequeue_task method is called before nr_running is
* decreased. We remove the task from the rbtree and
* update the fair scheduling stats:
*/
static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
{
struct cfs_rq *cfs_rq;
struct sched_entity *se = &p->se;
int task_sleep = flags & DEQUEUE_SLEEP;
for_each_sched_entity(se) {
cfs_rq = cfs_rq_of(se);
dequeue_entity(cfs_rq, se, flags);
/*
* end evaluation on encountering a throttled cfs_rq
*
* note: in the case of encountering a throttled cfs_rq we will
* post the final h_nr_running decrement below.
*/
if (cfs_rq_throttled(cfs_rq))
break;
cfs_rq->h_nr_running--;
/* Don't dequeue parent if it has other entities besides us */
if (cfs_rq->load.weight) {
/*
* Bias pick_next to pick a task from this cfs_rq, as
* p is sleeping when it is within its sched_slice.
*/
if (task_sleep && parent_entity(se))
set_next_buddy(parent_entity(se));
/* avoid re-evaluating load for this entity */
se = parent_entity(se);
break;
}
flags |= DEQUEUE_SLEEP;
}
for_each_sched_entity(se) {
cfs_rq = cfs_rq_of(se);
cfs_rq->h_nr_running--;
if (cfs_rq_throttled(cfs_rq))
break;
update_cfs_shares(cfs_rq);
update_entity_load_avg(se, 1);
}
if (!se) {
dec_nr_running(rq);
#ifndef CONFIG_CFS_BANDWIDTH
BUG_ON(rq->cfs.nr_running > rq->cfs.h_nr_running);
#endif
update_rq_runnable_avg(rq, 1);
}
hrtick_update(rq);
#ifdef CONFIG_HMP_TRACER
trace_sched_runqueue_length(rq->cpu,rq->nr_running);
trace_sched_cfs_length(rq->cpu,rq->cfs.h_nr_running);
#endif
#ifdef CONFIG_MET_SCHED_HMP
RqLen(rq->cpu,rq->nr_running);
CfsLen(rq->cpu,rq->cfs.h_nr_running);
#endif
#ifdef CONFIG_MTK_SCHED_CMP_TGS
sched_tg_dequeue_fair(rq, p);
#endif
}
#ifdef CONFIG_SMP
/* Used instead of source_load when we know the type == 0 */
static unsigned long weighted_cpuload(const int cpu)
{
return cpu_rq(cpu)->cfs.runnable_load_avg;
}
/*
* Return a low guess at the load of a migration-source cpu weighted
* according to the scheduling class and "nice" value.
*
* We want to under-estimate the load of migration sources, to
* balance conservatively.
*/
static unsigned long source_load(int cpu, int type)
{
struct rq *rq = cpu_rq(cpu);
unsigned long total = weighted_cpuload(cpu);
if (type == 0 || !sched_feat(LB_BIAS))
return total;
return min(rq->cpu_load[type-1], total);
}
/*
* Return a high guess at the load of a migration-target cpu weighted
* according to the scheduling class and "nice" value.
*/
static unsigned long target_load(int cpu, int type)
{
struct rq *rq = cpu_rq(cpu);
unsigned long total = weighted_cpuload(cpu);
if (type == 0 || !sched_feat(LB_BIAS))
return total;
return max(rq->cpu_load[type-1], total);
}
static unsigned long power_of(int cpu)
{
return cpu_rq(cpu)->cpu_power;
}
static unsigned long cpu_avg_load_per_task(int cpu)
{
struct rq *rq = cpu_rq(cpu);
unsigned long nr_running = ACCESS_ONCE(rq->nr_running);
unsigned long load_avg = rq->cfs.runnable_load_avg;
if (nr_running)
return load_avg / nr_running;
return 0;
}
static void task_waking_fair(struct task_struct *p)
{
struct sched_entity *se = &p->se;
struct cfs_rq *cfs_rq = cfs_rq_of(se);
u64 min_vruntime;
#ifndef CONFIG_64BIT
u64 min_vruntime_copy;
do {
min_vruntime_copy = cfs_rq->min_vruntime_copy;
smp_rmb();
min_vruntime = cfs_rq->min_vruntime;
} while (min_vruntime != min_vruntime_copy);
#else
min_vruntime = cfs_rq->min_vruntime;
#endif
se->vruntime -= min_vruntime;
}
#ifdef CONFIG_FAIR_GROUP_SCHED
/*
* effective_load() calculates the load change as seen from the root_task_group
*
* Adding load to a group doesn't make a group heavier, but can cause movement
* of group shares between cpus. Assuming the shares were perfectly aligned one
* can calculate the shift in shares.
*
* Calculate the effective load difference if @wl is added (subtracted) to @tg
* on this @cpu and results in a total addition (subtraction) of @wg to the
* total group weight.
*
* Given a runqueue weight distribution (rw_i) we can compute a shares
* distribution (s_i) using:
*
* s_i = rw_i / \Sum rw_j (1)
*
* Suppose we have 4 CPUs and our @tg is a direct child of the root group and
* has 7 equal weight tasks, distributed as below (rw_i), with the resulting
* shares distribution (s_i):
*
* rw_i = { 2, 4, 1, 0 }
* s_i = { 2/7, 4/7, 1/7, 0 }
*
* As per wake_affine() we're interested in the load of two CPUs (the CPU the
* task used to run on and the CPU the waker is running on), we need to
* compute the effect of waking a task on either CPU and, in case of a sync
* wakeup, compute the effect of the current task going to sleep.
*
* So for a change of @wl to the local @cpu with an overall group weight change
* of @wl we can compute the new shares distribution (s'_i) using:
*
* s'_i = (rw_i + @wl) / (@wg + \Sum rw_j) (2)
*
* Suppose we're interested in CPUs 0 and 1, and want to compute the load
* differences in waking a task to CPU 0. The additional task changes the
* weight and shares distributions like:
*
* rw'_i = { 3, 4, 1, 0 }
* s'_i = { 3/8, 4/8, 1/8, 0 }
*
* We can then compute the difference in effective weight by using:
*
* dw_i = S * (s'_i - s_i) (3)
*
* Where 'S' is the group weight as seen by its parent.
*
* Therefore the effective change in loads on CPU 0 would be 5/56 (3/8 - 2/7)
* times the weight of the group. The effect on CPU 1 would be -4/56 (4/8 -
* 4/7) times the weight of the group.
*/
static long effective_load(struct task_group *tg, int cpu, long wl, long wg)
{
struct sched_entity *se = tg->se[cpu];
if (!tg->parent) /* the trivial, non-cgroup case */
return wl;
for_each_sched_entity(se) {
long w, W;
tg = se->my_q->tg;
/*
* W = @wg + \Sum rw_j
*/
W = wg + calc_tg_weight(tg, se->my_q);
/*
* w = rw_i + @wl
*/
w = se->my_q->load.weight + wl;
/*
* wl = S * s'_i; see (2)
*/
if (W > 0 && w < W)
wl = (w * tg->shares) / W;
else
wl = tg->shares;
/*
* Per the above, wl is the new se->load.weight value; since
* those are clipped to [MIN_SHARES, ...) do so now. See
* calc_cfs_shares().
*/
if (wl < MIN_SHARES)
wl = MIN_SHARES;
/*
* wl = dw_i = S * (s'_i - s_i); see (3)
*/
wl -= se->load.weight;
/*
* Recursively apply this logic to all parent groups to compute
* the final effective load change on the root group. Since
* only the @tg group gets extra weight, all parent groups can
* only redistribute existing shares. @wl is the shift in shares
* resulting from this level per the above.
*/
wg = 0;
}
return wl;
}
#else
static inline unsigned long effective_load(struct task_group *tg, int cpu,
unsigned long wl, unsigned long wg)
{
return wl;
}
#endif
static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
{
s64 this_load, load;
int idx, this_cpu, prev_cpu;
unsigned long tl_per_task;
struct task_group *tg;
unsigned long weight;
int balanced;
idx = sd->wake_idx;
this_cpu = smp_processor_id();
prev_cpu = task_cpu(p);
load = source_load(prev_cpu, idx);
this_load = target_load(this_cpu, idx);
/*
* If sync wakeup then subtract the (maximum possible)
* effect of the currently running task from the load
* of the current CPU:
*/
if (sync) {
tg = task_group(current);
weight = current->se.load.weight;
this_load += effective_load(tg, this_cpu, -weight, -weight);
load += effective_load(tg, prev_cpu, 0, -weight);
}
tg = task_group(p);
weight = p->se.load.weight;
/*
* In low-load situations, where prev_cpu is idle and this_cpu is idle
* due to the sync cause above having dropped this_load to 0, we'll
* always have an imbalance, but there's really nothing you can do
* about that, so that's good too.
*
* Otherwise check if either cpus are near enough in load to allow this
* task to be woken on this_cpu.
*/
if (this_load > 0) {
s64 this_eff_load, prev_eff_load;
this_eff_load = 100;
this_eff_load *= power_of(prev_cpu);
this_eff_load *= this_load +
effective_load(tg, this_cpu, weight, weight);
prev_eff_load = 100 + (sd->imbalance_pct - 100) / 2;
prev_eff_load *= power_of(this_cpu);
prev_eff_load *= load + effective_load(tg, prev_cpu, 0, weight);
balanced = this_eff_load <= prev_eff_load;
} else
balanced = true;
/*
* If the currently running task will sleep within
* a reasonable amount of time then attract this newly
* woken task:
*/
if (sync && balanced)
return 1;
schedstat_inc(p, se.statistics.nr_wakeups_affine_attempts);
tl_per_task = cpu_avg_load_per_task(this_cpu);
if (balanced ||
(this_load <= load &&
this_load + target_load(prev_cpu, idx) <= tl_per_task)) {
/*
* This domain has SD_WAKE_AFFINE and
* p is cache cold in this domain, and
* there is no bad imbalance.
*/
schedstat_inc(sd, ttwu_move_affine);
schedstat_inc(p, se.statistics.nr_wakeups_affine);
return 1;
}
return 0;
}
/*
* find_idlest_group finds and returns the least busy CPU group within the
* domain.
*/
static struct sched_group *
find_idlest_group(struct sched_domain *sd, struct task_struct *p,
int this_cpu, int load_idx)
{
struct sched_group *idlest = NULL, *group = sd->groups;
unsigned long min_load = ULONG_MAX, this_load = 0;
int imbalance = 100 + (sd->imbalance_pct-100)/2;
do {
unsigned long load, avg_load;
int local_group;
int i;
/* Skip over this group if it has no CPUs allowed */
if (!cpumask_intersects(sched_group_cpus(group),
tsk_cpus_allowed(p)))
continue;
local_group = cpumask_test_cpu(this_cpu,
sched_group_cpus(group));
/* Tally up the load of all CPUs in the group */
avg_load = 0;
for_each_cpu(i, sched_group_cpus(group)) {
/* Bias balancing toward cpus of our domain */
if (local_group)
load = source_load(i, load_idx);
else
load = target_load(i, load_idx);
avg_load += load;
mt_sched_printf("find_idlest_group cpu=%d avg=%lu",
i, avg_load);
}
/* Adjust by relative CPU power of the group */
avg_load = (avg_load * SCHED_POWER_SCALE) / group->sgp->power;
if (local_group) {
this_load = avg_load;
mt_sched_printf("find_idlest_group this_load=%lu",
this_load);
} else if (avg_load < min_load) {
min_load = avg_load;
idlest = group;
mt_sched_printf("find_idlest_group min_load=%lu",
min_load);
}
} while (group = group->next, group != sd->groups);
if (!idlest || 100*this_load < imbalance*min_load){
mt_sched_printf("find_idlest_group fail this_load=%lu min_load=%lu, imbalance=%d",
this_load, min_load, imbalance);
return NULL;
}
return idlest;
}
/*
* find_idlest_cpu - find the idlest cpu among the cpus in group.
*/
static int
find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
{
unsigned long load, min_load = ULONG_MAX;
int idlest = -1;
int i;
/* Traverse only the allowed CPUs */
for_each_cpu_and(i, sched_group_cpus(group), tsk_cpus_allowed(p)) {
load = weighted_cpuload(i);
if (load < min_load || (load == min_load && i == this_cpu)) {
min_load = load;
idlest = i;
}
}
return idlest;
}
/*
* Try and locate an idle CPU in the sched_domain.
*/
static int select_idle_sibling(struct task_struct *p, int target)
{
struct sched_domain *sd;
struct sched_group *sg;
int i = task_cpu(p);
if (idle_cpu(target))
return target;
/*
* If the prevous cpu is cache affine and idle, don't be stupid.
*/
if (i != target && cpus_share_cache(i, target) && idle_cpu(i))
return i;
/*
* Otherwise, iterate the domains and find an elegible idle cpu.
*/
sd = rcu_dereference(per_cpu(sd_llc, target));
for_each_lower_domain(sd) {
sg = sd->groups;
do {
if (!cpumask_intersects(sched_group_cpus(sg),
tsk_cpus_allowed(p)))
goto next;
for_each_cpu(i, sched_group_cpus(sg)) {
if (i == target || !idle_cpu(i))
goto next;
}
target = cpumask_first_and(sched_group_cpus(sg),
tsk_cpus_allowed(p));
goto done;
next:
sg = sg->next;
} while (sg != sd->groups);
}
done:
return target;
}
#ifdef CONFIG_MTK_SCHED_CMP_TGS_WAKEUP
/*
* @p: the task want to be located at.
* @clid: the CPU cluster id to be search for the target CPU
* @target: the appropriate CPU for task p, updated by this function.
*
* Return:
*
* 1 on success
* 0 if target CPU is not found in this CPU cluster
*/
static int cmp_find_idle_cpu(struct task_struct *p, int clid, int *target)
{
struct cpumask cls_cpus;
int j;
get_cluster_cpus(&cls_cpus, clid, true);
*target = cpumask_any_and(&cls_cpus, tsk_cpus_allowed(p));
for_each_cpu(j, &cls_cpus) {
if (idle_cpu(j) && cpumask_test_cpu(j, tsk_cpus_allowed(p))) {
*target = j;
break;
}
}
if (*target >= nr_cpu_ids)
return 0; // task is not allow in this CPU cluster
mt_sched_printf("wakeup %d %s cpu=%d, max_clid/max_idle_clid=%d",
p->pid, p->comm, *target, clid);
return 1;
}
#if !defined(CONFIG_SCHED_HMP)
#define TGS_WAKEUP_EXPERIMENT
#endif
static int cmp_select_task_rq_fair(struct task_struct *p, int sd_flag, int *cpu)
{
int i, j;
int max_cnt=0, tskcnt;
int tgs_clid=-1;
int idle_cnt, max_idle_cnt=0;
int in_prev=0, prev_cluster=0;
struct cpumask cls_cpus;
int num_cluster;
num_cluster=arch_get_nr_clusters();
for(i=0; i< num_cluster; i++) {
tskcnt= p->group_leader->thread_group_info[i].nr_running;
idle_cnt = 0;
get_cluster_cpus(&cls_cpus, i, true);
for_each_cpu(j, &cls_cpus) {
#ifdef TGS_WAKEUP_EXPERIMENT
if (arch_is_big_little()) {
int bcpu = arch_cpu_is_big(j);
if (bcpu && p->se.avg.load_avg_ratio >= cmp_up_threshold) {
in_prev = 0;
tgs_clid = i;
mt_sched_printf("[heavy task] wakeup load=%ld up_th=%u pid=%d name=%s cpu=%d, tgs_clid=%d in_prev=%d",
p->se.avg.load_avg_ratio, cmp_up_threshold, p->pid, p->comm, *cpu, tgs_clid, in_prev);
goto find_idle_cpu;
}
if (!bcpu && p->se.avg.load_avg_ratio < cmp_down_threshold) {
in_prev = 0;
tgs_clid = i;
mt_sched_printf("[light task] wakeup load=%ld down_th=%u pid=%d name=%s cpu=%d, tgs_clid=%d in_prev=%d",
p->se.avg.load_avg_ratio, cmp_down_threshold, p->pid, p->comm, *cpu, tgs_clid, in_prev);
goto find_idle_cpu;
}
}
#endif
if (idle_cpu(j))
idle_cnt++;
}
mt_sched_printf("wakeup load=%ld pid=%d name=%s clid=%d idle_cnt=%d tskcnt=%d max_cnt=%d, cls_cpus=%02lx, onlineCPU=%02lx",
p->se.avg.load_avg_ratio, p->pid, p->comm, i, idle_cnt, tskcnt, max_cnt,
*cpumask_bits(&cls_cpus), *cpumask_bits(cpu_online_mask));
if (idle_cnt == 0)
continue;
if (i == get_cluster_id(*cpu))
prev_cluster = 1;
if (tskcnt > 0) {
if ( (tskcnt > max_cnt) || ((tskcnt == max_cnt) && prev_cluster)) {
in_prev = prev_cluster;
tgs_clid = i;
max_cnt = tskcnt;
}
} else if (0 == max_cnt) {
if ((idle_cnt > max_idle_cnt) || ((idle_cnt == max_idle_cnt) && prev_cluster)) {
in_prev = prev_cluster;
tgs_clid = i ;
max_idle_cnt = idle_cnt;
}
}
mt_sched_printf("wakeup %d %s i=%d idle_cnt=%d tgs_clid=%d max_cnt=%d max_idle_cnt=%d in_prev=%d",
p->pid, p->comm, i, idle_cnt, tgs_clid, max_cnt, max_idle_cnt, in_prev);
}
#ifdef TGS_WAKEUP_EXPERIMENT
find_idle_cpu:
#endif
mt_sched_printf("wakeup %d %s cpu=%d, tgs_clid=%d in_prev=%d",
p->pid, p->comm, *cpu, tgs_clid, in_prev);
if(-1 != tgs_clid && !in_prev && cmp_find_idle_cpu(p, tgs_clid, cpu))
return 1;
return 0;
}
#endif
#ifdef CONFIG_MTK_SCHED_TRACERS
#define LB_RESET 0
#define LB_AFFINITY 0x10
#define LB_BUDDY 0x20
#define LB_FORK 0x30
#define LB_CMP_SHIFT 8
#define LB_CMP 0x4000
#define LB_SMP_SHIFT 16
#define LB_SMP 0x500000
#define LB_HMP_SHIFT 24
#define LB_HMP 0x60000000
#endif
/*
* sched_balance_self: balance the current task (running on cpu) in domains
* that have the 'flag' flag set. In practice, this is SD_BALANCE_FORK and
* SD_BALANCE_EXEC.
*
* Balance, ie. select the least loaded group.
*
* Returns the target CPU number, or the same CPU if no balancing is needed.
*
* preempt must be disabled.
*/
static int
select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flags)
{
struct sched_domain *tmp, *affine_sd = NULL, *sd = NULL;
int cpu = smp_processor_id();
int prev_cpu = task_cpu(p);
int new_cpu = cpu;
int want_affine = 0;
int sync = wake_flags & WF_SYNC;
#if defined(CONFIG_SCHED_HMP) && !defined(CONFIG_SCHED_HMP_ENHANCEMENT)
int target_cpu = nr_cpu_ids;
#endif
#ifdef CONFIG_MTK_SCHED_TRACERS
int policy = 0;
#endif
#ifdef CONFIG_MTK_SCHED_CMP_TGS_WAKEUP
int cmp_cpu;
int cmp_cpu_found=0;
#endif
#ifdef CONFIG_MTK_SCHED_CMP_PACK_SMALL_TASK
int buddy_cpu = per_cpu(sd_pack_buddy, cpu);
#endif
if (p->nr_cpus_allowed == 1)
{
#ifdef CONFIG_MTK_SCHED_TRACERS
trace_sched_select_task_rq(p, (LB_AFFINITY | prev_cpu), prev_cpu, prev_cpu);
#endif
return prev_cpu;
}
#ifdef CONFIG_HMP_PACK_SMALL_TASK
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
if (check_pack_buddy(cpu, p) && PA_ENABLE) {
PACK_FROM_CPUX_TO_CPUY_COUNT[cpu][per_cpu(sd_pack_buddy, cpu)]++;
#ifdef CONFIG_HMP_TRACER
trace_sched_power_aware_active(POWER_AWARE_ACTIVE_MODULE_PACK_FORM_CPUX_TO_CPUY, p->pid, cpu, per_cpu(sd_pack_buddy, cpu));
#endif /* CONFIG_HMP_TRACER */
if(PA_MON_ENABLE) {
if(strcmp(p->comm, PA_MON) == 0 && cpu != per_cpu(sd_pack_buddy, cpu)) {
printk(KERN_EMERG "[PA] %s PACK From CPU%d to CPU%d\n", p->comm, cpu, per_cpu(sd_pack_buddy, cpu));
printk(KERN_EMERG "[PA] Buddy RQ Usage = %u, Period = %u, NR = %u\n",
per_cpu(BUDDY_CPU_RQ_USAGE, per_cpu(sd_pack_buddy, cpu)),
per_cpu(BUDDY_CPU_RQ_PERIOD, per_cpu(sd_pack_buddy, cpu)),
per_cpu(BUDDY_CPU_RQ_NR, per_cpu(sd_pack_buddy, cpu)));
printk(KERN_EMERG "[PA] Task Usage = %u, Period = %u\n",
per_cpu(TASK_USGAE, cpu),
per_cpu(TASK_PERIOD, cpu));
}
}
#else /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
if (check_pack_buddy(cpu, p)) {
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
#ifdef CONFIG_MTK_SCHED_TRACERS
new_cpu = per_cpu(sd_pack_buddy, cpu);
trace_sched_select_task_rq(p, (LB_BUDDY | new_cpu), prev_cpu, new_cpu);
#endif
return per_cpu(sd_pack_buddy, cpu);
}
#elif defined (CONFIG_MTK_SCHED_CMP_PACK_SMALL_TASK)
#ifdef CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER
if (PA_ENABLE && (sd_flag & SD_BALANCE_WAKE) && (check_pack_buddy(buddy_cpu, p))) {
#else
if ((sd_flag & SD_BALANCE_WAKE) && (check_pack_buddy(buddy_cpu, p))) {
#endif
struct thread_group_info_t *src_tginfo, *dst_tginfo;
src_tginfo = &p->group_leader->thread_group_info[get_cluster_id(prev_cpu)]; //Compare with previous cpu(Not current cpu)
dst_tginfo = &p->group_leader->thread_group_info[get_cluster_id(buddy_cpu)];
if((get_cluster_id(prev_cpu) == get_cluster_id(buddy_cpu)) ||
(src_tginfo->nr_running < dst_tginfo->nr_running))
{
#ifdef CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER
PACK_FROM_CPUX_TO_CPUY_COUNT[cpu][buddy_cpu]++;
mt_sched_printf("[PA]pid=%d, Pack to CPU%d(CPU%d's buddy)\n", p->pid,buddy_cpu,cpu);
if(PA_MON_ENABLE) {
u8 i=0;
for(i=0;i<4; i++) {
if(strcmp(p->comm, &PA_MON[i][0]) == 0) {
TASK_PACK_CPU_COUNT[i][buddy_cpu]++;
printk(KERN_EMERG "[PA] %s PACK to CPU%d(CPU%d's buddy), pre(cpu%d)\n", p->comm, buddy_cpu,cpu, prev_cpu);
printk(KERN_EMERG "[PA] Buddy RQ Usage = %u, Period = %u, NR = %u\n",
per_cpu(BUDDY_CPU_RQ_USAGE, buddy_cpu),
per_cpu(BUDDY_CPU_RQ_PERIOD, buddy_cpu),
per_cpu(BUDDY_CPU_RQ_NR, buddy_cpu));
printk(KERN_EMERG "[PA] Task Usage = %u, Period = %u\n",
per_cpu(TASK_USGAE, cpu),
per_cpu(TASK_PERIOD, cpu));
break;
}
}
}
#endif //CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER
#ifdef CONFIG_MTK_SCHED_TRACERS
trace_sched_select_task_rq(p, (LB_BUDDY | buddy_cpu), prev_cpu, buddy_cpu);
#endif
return buddy_cpu;
}
}
#endif /* CONFIG_HMP_PACK_SMALL_TASK */
#ifdef CONFIG_SCHED_HMP
/* always put non-kernel forking tasks on a big domain */
if (p->mm && (sd_flag & SD_BALANCE_FORK)) {
if(hmp_cpu_is_fastest(prev_cpu)) {
struct hmp_domain *hmpdom = list_entry(&hmp_cpu_domain(prev_cpu)->hmp_domains, struct hmp_domain, hmp_domains);
__always_unused int lowest_ratio = hmp_domain_min_load(hmpdom, &new_cpu);
if(new_cpu < nr_cpu_ids && cpumask_test_cpu(new_cpu,tsk_cpus_allowed(p)))
{
#ifdef CONFIG_MTK_SCHED_TRACERS
trace_sched_select_task_rq(p, (LB_FORK | new_cpu), prev_cpu, new_cpu);
#endif
return new_cpu;
}
else
{
new_cpu = cpumask_any_and(&hmp_faster_domain(cpu)->cpus,
tsk_cpus_allowed(p));
if(new_cpu < nr_cpu_ids)
{
#ifdef CONFIG_MTK_SCHED_TRACERS
trace_sched_select_task_rq(p, (LB_FORK | new_cpu), prev_cpu, new_cpu);
#endif
return new_cpu;
}
}
} else {
new_cpu = hmp_select_faster_cpu(p, prev_cpu);
if (new_cpu < nr_cpu_ids)
{
#ifdef CONFIG_MTK_SCHED_TRACERS
trace_sched_select_task_rq(p, (LB_FORK | new_cpu), prev_cpu, new_cpu);
#endif
return new_cpu;
}
}
// to recover new_cpu value
if (new_cpu >= nr_cpu_ids)
new_cpu = cpu;
}
#endif
if (sd_flag & SD_BALANCE_WAKE) {
if (cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
want_affine = 1;
new_cpu = prev_cpu;
}
#ifdef CONFIG_MTK_SCHED_CMP_TGS_WAKEUP
cmp_cpu = prev_cpu;
cmp_cpu_found = cmp_select_task_rq_fair(p, sd_flag, &cmp_cpu);
if (cmp_cpu_found && (cmp_cpu < nr_cpu_ids)) {
cpu = cmp_cpu;
new_cpu = cmp_cpu;
#ifdef CONFIG_MTK_SCHED_TRACERS
policy |= (new_cpu << LB_CMP_SHIFT);
policy |= LB_CMP;
#endif
mt_sched_printf("wakeup %d %s sd_flag=%x cmp_cpu_found=%d, cpu=%d, want_affine=%d ",
p->pid, p->comm, sd_flag, cmp_cpu_found, cpu, want_affine);
goto cmp_found;
}
#endif
rcu_read_lock();
for_each_domain(cpu, tmp) {
mt_sched_printf("wakeup %d %s tmp->flags=%x, cpu=%d, prev_cpu=%d, new_cpu=%d",
p->pid, p->comm, tmp->flags, cpu, prev_cpu, new_cpu);
if (!(tmp->flags & SD_LOAD_BALANCE))
continue;
/*
* If both cpu and prev_cpu are part of this domain,
* cpu is a valid SD_WAKE_AFFINE target.
*/
if (want_affine && (tmp->flags & SD_WAKE_AFFINE) &&
cpumask_test_cpu(prev_cpu, sched_domain_span(tmp))) {
affine_sd = tmp;
break;
}
if (tmp->flags & sd_flag)
sd = tmp;
}
if (affine_sd) {
if (cpu != prev_cpu && wake_affine(affine_sd, p, sync))
prev_cpu = cpu;
new_cpu = select_idle_sibling(p, prev_cpu);
goto unlock;
}
mt_sched_printf("wakeup %d %s sd=%p", p->pid, p->comm, sd);
while (sd) {
int load_idx = sd->forkexec_idx;
struct sched_group *group;
int weight;
mt_sched_printf("wakeup %d %s find_idlest_group cpu=%d sd->flags=%x sd_flag=%x",
p->pid, p->comm, cpu, sd->flags, sd_flag);
if (!(sd->flags & sd_flag)) {
sd = sd->child;
continue;
}
if (sd_flag & SD_BALANCE_WAKE)
load_idx = sd->wake_idx;
mt_sched_printf("wakeup %d %s find_idlest_group cpu=%d",
p->pid, p->comm, cpu);
group = find_idlest_group(sd, p, cpu, load_idx);
if (!group) {
sd = sd->child;
mt_sched_printf("wakeup %d %s find_idlest_group child",
p->pid, p->comm);
continue;
}
new_cpu = find_idlest_cpu(group, p, cpu);
if (new_cpu == -1 || new_cpu == cpu) {
/* Now try balancing at a lower domain level of cpu */
sd = sd->child;
mt_sched_printf("wakeup %d %s find_idlest_cpu sd->child=%p",
p->pid, p->comm, sd);
continue;
}
/* Now try balancing at a lower domain level of new_cpu */
mt_sched_printf("wakeup %d %s find_idlest_cpu cpu=%d sd=%p",
p->pid, p->comm, new_cpu, sd);
cpu = new_cpu;
weight = sd->span_weight;
sd = NULL;
for_each_domain(cpu, tmp) {
if (weight <= tmp->span_weight)
break;
if (tmp->flags & sd_flag)
sd = tmp;
mt_sched_printf("wakeup %d %s sd=%p weight=%d, tmp->span_weight=%d",
p->pid, p->comm, sd, weight, tmp->span_weight);
}
/* while loop will break here if sd == NULL */
}
#ifdef CONFIG_MTK_SCHED_TRACERS
policy |= (new_cpu << LB_SMP_SHIFT);
policy |= LB_SMP;
#endif
unlock:
rcu_read_unlock();
mt_sched_printf("wakeup %d %s new_cpu=%x", p->pid, p->comm, new_cpu);
#ifdef CONFIG_MTK_SCHED_CMP_TGS_WAKEUP
cmp_found:
#endif
#ifdef CONFIG_SCHED_HMP
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
new_cpu = hmp_select_task_rq_fair(sd_flag, p, prev_cpu, new_cpu);
#ifdef CONFIG_MTK_SCHED_TRACERS
policy |= (new_cpu << LB_HMP_SHIFT);
policy |= LB_HMP;
#endif
#else
if (hmp_up_migration(prev_cpu, &target_cpu, &p->se)) {
new_cpu = hmp_select_faster_cpu(p, prev_cpu);
hmp_next_up_delay(&p->se, new_cpu);
trace_sched_hmp_migrate(p, new_cpu, 0);
return new_cpu;
}
if (hmp_down_migration(prev_cpu, &p->se)) {
new_cpu = hmp_select_slower_cpu(p, prev_cpu);
hmp_next_down_delay(&p->se, new_cpu);
trace_sched_hmp_migrate(p, new_cpu, 0);
return new_cpu;
}
/* Make sure that the task stays in its previous hmp domain */
if (!cpumask_test_cpu(new_cpu, &hmp_cpu_domain(prev_cpu)->cpus))
return prev_cpu;
#endif /* CONFIG_SCHED_HMP_ENHANCEMENT */
#endif /* CONFIG_SCHED_HMP */
#ifdef CONFIG_MTK_SCHED_TRACERS
trace_sched_select_task_rq(p, policy, prev_cpu, new_cpu);
#endif
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
if(PA_MON_ENABLE) {
if(strcmp(p->comm, PA_MON) == 0 && cpu != new_cpu) {
printk(KERN_EMERG "[PA] %s Select From CPU%d to CPU%d\n", p->comm, cpu, new_cpu);
}
}
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
return new_cpu;
}
/*
* Called immediately before a task is migrated to a new cpu; task_cpu(p) and
* cfs_rq_of(p) references at time of call are still valid and identify the
* previous cpu. However, the caller only guarantees p->pi_lock is held; no
* other assumptions, including the state of rq->lock, should be made.
*/
static void
migrate_task_rq_fair(struct task_struct *p, int next_cpu)
{
struct sched_entity *se = &p->se;
struct cfs_rq *cfs_rq = cfs_rq_of(se);
/*
* Load tracking: accumulate removed load so that it can be processed
* when we next update owning cfs_rq under rq->lock. Tasks contribute
* to blocked load iff they have a positive decay-count. It can never
* be negative here since on-rq tasks have decay-count == 0.
*/
if (se->avg.decay_count) {
se->avg.decay_count = -__synchronize_entity_decay(se);
atomic_long_add(se->avg.load_avg_contrib,
&cfs_rq->removed_load);
}
}
#endif /* CONFIG_SMP */
static unsigned long
wakeup_gran(struct sched_entity *curr, struct sched_entity *se)
{
unsigned long gran = sysctl_sched_wakeup_granularity;
/*
* Since its curr running now, convert the gran from real-time
* to virtual-time in his units.
*
* By using 'se' instead of 'curr' we penalize light tasks, so
* they get preempted easier. That is, if 'se' < 'curr' then
* the resulting gran will be larger, therefore penalizing the
* lighter, if otoh 'se' > 'curr' then the resulting gran will
* be smaller, again penalizing the lighter task.
*
* This is especially important for buddies when the leftmost
* task is higher priority than the buddy.
*/
return calc_delta_fair(gran, se);
}
/*
* Should 'se' preempt 'curr'.
*
* |s1
* |s2
* |s3
* g
* |<--->|c
*
* w(c, s1) = -1
* w(c, s2) = 0
* w(c, s3) = 1
*
*/
static int
wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se)
{
s64 gran, vdiff = curr->vruntime - se->vruntime;
if (vdiff <= 0)
return -1;
gran = wakeup_gran(curr, se);
if (vdiff > gran)
return 1;
return 0;
}
static void set_last_buddy(struct sched_entity *se)
{
if (entity_is_task(se) && unlikely(task_of(se)->policy == SCHED_IDLE))
return;
for_each_sched_entity(se)
cfs_rq_of(se)->last = se;
}
static void set_next_buddy(struct sched_entity *se)
{
if (entity_is_task(se) && unlikely(task_of(se)->policy == SCHED_IDLE))
return;
for_each_sched_entity(se)
cfs_rq_of(se)->next = se;
}
static void set_skip_buddy(struct sched_entity *se)
{
for_each_sched_entity(se)
cfs_rq_of(se)->skip = se;
}
/*
* Preempt the current task with a newly woken task if needed:
*/
static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_flags)
{
struct task_struct *curr = rq->curr;
struct sched_entity *se = &curr->se, *pse = &p->se;
struct cfs_rq *cfs_rq = task_cfs_rq(curr);
int scale = cfs_rq->nr_running >= sched_nr_latency;
int next_buddy_marked = 0;
if (unlikely(se == pse))
return;
/*
* This is possible from callers such as move_task(), in which we
* unconditionally check_prempt_curr() after an enqueue (which may have
* lead to a throttle). This both saves work and prevents false
* next-buddy nomination below.
*/
if (unlikely(throttled_hierarchy(cfs_rq_of(pse))))
return;
if (sched_feat(NEXT_BUDDY) && scale && !(wake_flags & WF_FORK)) {
set_next_buddy(pse);
next_buddy_marked = 1;
}
/*
* We can come here with TIF_NEED_RESCHED already set from new task
* wake up path.
*
* Note: this also catches the edge-case of curr being in a throttled
* group (e.g. via set_curr_task), since update_curr() (in the
* enqueue of curr) will have resulted in resched being set. This
* prevents us from potentially nominating it as a false LAST_BUDDY
* below.
*/
if (test_tsk_need_resched(curr))
return;
/* Idle tasks are by definition preempted by non-idle tasks. */
if (unlikely(curr->policy == SCHED_IDLE) &&
likely(p->policy != SCHED_IDLE))
goto preempt;
/*
* Batch and idle tasks do not preempt non-idle tasks (their preemption
* is driven by the tick):
*/
if (unlikely(p->policy != SCHED_NORMAL) || !sched_feat(WAKEUP_PREEMPTION))
return;
find_matching_se(&se, &pse);
update_curr(cfs_rq_of(se));
BUG_ON(!pse);
if (wakeup_preempt_entity(se, pse) == 1) {
/*
* Bias pick_next to pick the sched entity that is
* triggering this preemption.
*/
if (!next_buddy_marked)
set_next_buddy(pse);
goto preempt;
}
return;
preempt:
resched_task(curr);
/*
* Only set the backward buddy when the current task is still
* on the rq. This can happen when a wakeup gets interleaved
* with schedule on the ->pre_schedule() or idle_balance()
* point, either of which can * drop the rq lock.
*
* Also, during early boot the idle thread is in the fair class,
* for obvious reasons its a bad idea to schedule back to it.
*/
if (unlikely(!se->on_rq || curr == rq->idle))
return;
if (sched_feat(LAST_BUDDY) && scale && entity_is_task(se))
set_last_buddy(se);
}
static struct task_struct *pick_next_task_fair(struct rq *rq)
{
struct task_struct *p;
struct cfs_rq *cfs_rq = &rq->cfs;
struct sched_entity *se;
// in case nr_running!=0 but h_nr_running==0
if (!cfs_rq->nr_running || !cfs_rq->h_nr_running)
return NULL;
do {
se = pick_next_entity(cfs_rq);
set_next_entity(cfs_rq, se);
cfs_rq = group_cfs_rq(se);
} while (cfs_rq);
p = task_of(se);
if (hrtick_enabled(rq))
hrtick_start_fair(rq, p);
return p;
}
/*
* Account for a descheduled task:
*/
static void put_prev_task_fair(struct rq *rq, struct task_struct *prev)
{
struct sched_entity *se = &prev->se;
struct cfs_rq *cfs_rq;
for_each_sched_entity(se) {
cfs_rq = cfs_rq_of(se);
put_prev_entity(cfs_rq, se);
}
}
/*
* sched_yield() is very simple
*
* The magic of dealing with the ->skip buddy is in pick_next_entity.
*/
static void yield_task_fair(struct rq *rq)
{
struct task_struct *curr = rq->curr;
struct cfs_rq *cfs_rq = task_cfs_rq(curr);
struct sched_entity *se = &curr->se;
/*
* Are we the only task in the tree?
*/
if (unlikely(rq->nr_running == 1))
return;
clear_buddies(cfs_rq, se);
if (curr->policy != SCHED_BATCH) {
update_rq_clock(rq);
/*
* Update run-time statistics of the 'current'.
*/
update_curr(cfs_rq);
/*
* Tell update_rq_clock() that we've just updated,
* so we don't do microscopic update in schedule()
* and double the fastpath cost.
*/
rq->skip_clock_update = 1;
}
set_skip_buddy(se);
}
static bool yield_to_task_fair(struct rq *rq, struct task_struct *p, bool preempt)
{
struct sched_entity *se = &p->se;
/* throttled hierarchies are not runnable */
if (!se->on_rq || throttled_hierarchy(cfs_rq_of(se)))
return false;
/* Tell the scheduler that we'd really like pse to run next. */
set_next_buddy(se);
yield_task_fair(rq);
return true;
}
#ifdef CONFIG_SMP
/**************************************************
* Fair scheduling class load-balancing methods.
*
* BASICS
*
* The purpose of load-balancing is to achieve the same basic fairness the
* per-cpu scheduler provides, namely provide a proportional amount of compute
* time to each task. This is expressed in the following equation:
*
* W_i,n/P_i == W_j,n/P_j for all i,j (1)
*
* Where W_i,n is the n-th weight average for cpu i. The instantaneous weight
* W_i,0 is defined as:
*
* W_i,0 = \Sum_j w_i,j (2)
*
* Where w_i,j is the weight of the j-th runnable task on cpu i. This weight
* is derived from the nice value as per prio_to_weight[].
*
* The weight average is an exponential decay average of the instantaneous
* weight:
*
* W'_i,n = (2^n - 1) / 2^n * W_i,n + 1 / 2^n * W_i,0 (3)
*
* P_i is the cpu power (or compute capacity) of cpu i, typically it is the
* fraction of 'recent' time available for SCHED_OTHER task execution. But it
* can also include other factors [XXX].
*
* To achieve this balance we define a measure of imbalance which follows
* directly from (1):
*
* imb_i,j = max{ avg(W/P), W_i/P_i } - min{ avg(W/P), W_j/P_j } (4)
*
* We them move tasks around to minimize the imbalance. In the continuous
* function space it is obvious this converges, in the discrete case we get
* a few fun cases generally called infeasible weight scenarios.
*
* [XXX expand on:
* - infeasible weights;
* - local vs global optima in the discrete case. ]
*
*
* SCHED DOMAINS
*
* In order to solve the imbalance equation (4), and avoid the obvious O(n^2)
* for all i,j solution, we create a tree of cpus that follows the hardware
* topology where each level pairs two lower groups (or better). This results
* in O(log n) layers. Furthermore we reduce the number of cpus going up the
* tree to only the first of the previous level and we decrease the frequency
* of load-balance at each level inv. proportional to the number of cpus in
* the groups.
*
* This yields:
*
* log_2 n 1 n
* \Sum { --- * --- * 2^i } = O(n) (5)
* i = 0 2^i 2^i
* `- size of each group
* | | `- number of cpus doing load-balance
* | `- freq
* `- sum over all levels
*
* Coupled with a limit on how many tasks we can migrate every balance pass,
* this makes (5) the runtime complexity of the balancer.
*
* An important property here is that each CPU is still (indirectly) connected
* to every other cpu in at most O(log n) steps:
*
* The adjacency matrix of the resulting graph is given by:
*
* log_2 n
* A_i,j = \Union (i % 2^k == 0) && i / 2^(k+1) == j / 2^(k+1) (6)
* k = 0
*
* And you'll find that:
*
* A^(log_2 n)_i,j != 0 for all i,j (7)
*
* Showing there's indeed a path between every cpu in at most O(log n) steps.
* The task movement gives a factor of O(m), giving a convergence complexity
* of:
*
* O(nm log n), n := nr_cpus, m := nr_tasks (8)
*
*
* WORK CONSERVING
*
* In order to avoid CPUs going idle while there's still work to do, new idle
* balancing is more aggressive and has the newly idle cpu iterate up the domain
* tree itself instead of relying on other CPUs to bring it work.
*
* This adds some complexity to both (5) and (8) but it reduces the total idle
* time.
*
* [XXX more?]
*
*
* CGROUPS
*
* Cgroups make a horror show out of (2), instead of a simple sum we get:
*
* s_k,i
* W_i,0 = \Sum_j \Prod_k w_k * ----- (9)
* S_k
*
* Where
*
* s_k,i = \Sum_j w_i,j,k and S_k = \Sum_i s_k,i (10)
*
* w_i,j,k is the weight of the j-th runnable task in the k-th cgroup on cpu i.
*
* The big problem is S_k, its a global sum needed to compute a local (W_i)
* property.
*
* [XXX write more on how we solve this.. _after_ merging pjt's patches that
* rewrite all of this once again.]
*/
static unsigned long __read_mostly max_load_balance_interval = HZ/10;
#define LBF_ALL_PINNED 0x01
#define LBF_NEED_BREAK 0x02
#define LBF_SOME_PINNED 0x04
struct lb_env {
struct sched_domain *sd;
struct rq *src_rq;
int src_cpu;
int dst_cpu;
struct rq *dst_rq;
struct cpumask *dst_grpmask;
int new_dst_cpu;
enum cpu_idle_type idle;
long imbalance;
/* The set of CPUs under consideration for load-balancing */
struct cpumask *cpus;
unsigned int flags;
unsigned int loop;
unsigned int loop_break;
unsigned int loop_max;
#ifdef CONFIG_MT_LOAD_BALANCE_ENHANCEMENT
int mt_check_cache_in_idle;
#endif
#ifdef CONFIG_MT_LOAD_BALANCE_PROFILER
unsigned int fail_reason;
#endif
};
/*
* move_task - move a task from one runqueue to another runqueue.
* Both runqueues must be locked.
*/
static void move_task(struct task_struct *p, struct lb_env *env)
{
deactivate_task(env->src_rq, p, 0);
set_task_cpu(p, env->dst_cpu);
activate_task(env->dst_rq, p, 0);
check_preempt_curr(env->dst_rq, p, 0);
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
if(PA_MON_ENABLE) {
if(strcmp(p->comm, PA_MON) == 0) {
printk(KERN_EMERG "[PA] %s Balance From CPU%d to CPU%d\n", p->comm, env->src_rq->cpu, env->dst_rq->cpu);
}
}
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
}
/*
* Is this task likely cache-hot:
*/
#if defined(CONFIG_MT_LOAD_BALANCE_ENHANCEMENT)
static int
task_hot(struct task_struct *p, u64 now, struct sched_domain *sd, int mt_check_cache_in_idle)
#else
static int
task_hot(struct task_struct *p, u64 now, struct sched_domain *sd)
#endif
{
s64 delta;
if (p->sched_class != &fair_sched_class)
return 0;
if (unlikely(p->policy == SCHED_IDLE))
return 0;
/*
* Buddy candidates are cache hot:
*/
#ifdef CONFIG_MT_LOAD_BALANCE_ENHANCEMENT
if (!mt_check_cache_in_idle){
if ( !this_rq()->nr_running && (task_rq(p)->nr_running >= 2) )
return 0;
}
#endif
if (sched_feat(CACHE_HOT_BUDDY) && this_rq()->nr_running &&
(&p->se == cfs_rq_of(&p->se)->next ||
&p->se == cfs_rq_of(&p->se)->last))
return 1;
if (sysctl_sched_migration_cost == -1)
return 1;
if (sysctl_sched_migration_cost == 0)
return 0;
delta = now - p->se.exec_start;
return delta < (s64)sysctl_sched_migration_cost;
}
/*
* can_migrate_task - may task p from runqueue rq be migrated to this_cpu?
*/
static
int can_migrate_task(struct task_struct *p, struct lb_env *env)
{
int tsk_cache_hot = 0;
/*
* We do not migrate tasks that are:
* 1) throttled_lb_pair, or
* 2) cannot be migrated to this CPU due to cpus_allowed, or
* 3) running (obviously), or
* 4) are cache-hot on their current CPU.
*/
if (throttled_lb_pair(task_group(p), env->src_cpu, env->dst_cpu))
return 0;
if (!cpumask_test_cpu(env->dst_cpu, tsk_cpus_allowed(p))) {
int cpu;
schedstat_inc(p, se.statistics.nr_failed_migrations_affine);
#ifdef CONFIG_MT_LOAD_BALANCE_PROFILER
mt_lbprof_stat_or(env->fail_reason, MT_LBPROF_AFFINITY);
if(mt_lbprof_lt (env->sd->mt_lbprof_nr_balance_failed, MT_LBPROF_NR_BALANCED_FAILED_UPPER_BOUND)){
char strings[128]="";
snprintf(strings, 128, "%d:balance fail:affinity:%d:%d:%s:0x%lu"
, env->dst_cpu, env->src_cpu, p->pid, p->comm, p->cpus_allowed.bits[0]);
trace_sched_lbprof_log(strings);
}
#endif
/*
* Remember if this task can be migrated to any other cpu in
* our sched_group. We may want to revisit it if we couldn't
* meet load balance goals by pulling other tasks on src_cpu.
*
* Also avoid computing new_dst_cpu if we have already computed
* one in current iteration.
*/
if (!env->dst_grpmask || (env->flags & LBF_SOME_PINNED))
return 0;
/* Prevent to re-select dst_cpu via env's cpus */
for_each_cpu_and(cpu, env->dst_grpmask, env->cpus) {
if (cpumask_test_cpu(cpu, tsk_cpus_allowed(p))) {
env->flags |= LBF_SOME_PINNED;
env->new_dst_cpu = cpu;
break;
}
}
return 0;
}
/* Record that we found atleast one task that could run on dst_cpu */
env->flags &= ~LBF_ALL_PINNED;
if (task_running(env->src_rq, p)) {
schedstat_inc(p, se.statistics.nr_failed_migrations_running);
#ifdef CONFIG_MT_LOAD_BALANCE_PROFILER
mt_lbprof_stat_or(env->fail_reason, MT_LBPROF_RUNNING);
if( mt_lbprof_lt (env->sd->mt_lbprof_nr_balance_failed, MT_LBPROF_NR_BALANCED_FAILED_UPPER_BOUND)){
char strings[128]="";
snprintf(strings, 128, "%d:balance fail:running:%d:%d:%s"
, env->dst_cpu, env->src_cpu, p->pid, p->comm);
trace_sched_lbprof_log(strings);
}
#endif
return 0;
}
/*
* Aggressive migration if:
* 1) task is cache cold, or
* 2) too many balance attempts have failed.
*/
#if defined(CONFIG_MT_LOAD_BALANCE_ENHANCEMENT)
tsk_cache_hot = task_hot(p, env->src_rq->clock_task, env->sd, env->mt_check_cache_in_idle);
#else
tsk_cache_hot = task_hot(p, env->src_rq->clock_task, env->sd);
#endif
if (!tsk_cache_hot ||
env->sd->nr_balance_failed > env->sd->cache_nice_tries) {
if (tsk_cache_hot) {
schedstat_inc(env->sd, lb_hot_gained[env->idle]);
schedstat_inc(p, se.statistics.nr_forced_migrations);
}
return 1;
}
schedstat_inc(p, se.statistics.nr_failed_migrations_hot);
#ifdef CONFIG_MT_LOAD_BALANCE_PROFILER
mt_lbprof_stat_or(env->fail_reason, MT_LBPROF_CACHEHOT);
if(mt_lbprof_lt (env->sd->mt_lbprof_nr_balance_failed, MT_LBPROF_NR_BALANCED_FAILED_UPPER_BOUND)){
char strings[128]="";
snprintf(strings, 128, "%d:balance fail:cache hot:%d:%d:%s"
, env->dst_cpu, env->src_cpu, p->pid, p->comm);
trace_sched_lbprof_log(strings);
}
#endif
return 0;
}
/*
* move_one_task tries to move exactly one task from busiest to this_rq, as
* part of active balancing operations within "domain".
* Returns 1 if successful and 0 otherwise.
*
* Called with both runqueues locked.
*/
static int move_one_task(struct lb_env *env)
{
struct task_struct *p, *n;
#ifdef CONFIG_MT_LOAD_BALANCE_ENHANCEMENT
env->mt_check_cache_in_idle = 1;
#endif
#ifdef CONFIG_MT_LOAD_BALANCE_PROFILER
mt_lbprof_stat_set(env->fail_reason, MT_LBPROF_NO_TRIGGER);
#endif
list_for_each_entry_safe(p, n, &env->src_rq->cfs_tasks, se.group_node) {
#if defined (CONFIG_MTK_SCHED_CMP_LAZY_BALANCE) && !defined(CONFIG_HMP_LAZY_BALANCE)
if(need_lazy_balance(env->dst_cpu, env->src_cpu, p))
continue;
#endif
if (!can_migrate_task(p, env))
continue;
move_task(p, env);
/*
* Right now, this is only the second place move_task()
* is called, so we can safely collect move_task()
* stats here rather than inside move_task().
*/
schedstat_inc(env->sd, lb_gained[env->idle]);
return 1;
}
return 0;
}
static unsigned long task_h_load(struct task_struct *p);
static const unsigned int sched_nr_migrate_break = 32;
/* in second round load balance, we migrate heavy load_weight task
as long as RT tasks exist in busy cpu*/
#ifdef CONFIG_MT_LOAD_BALANCE_ENHANCEMENT
#define over_imbalance(lw, im) \
(((lw)/2 > (im)) && \
((env->mt_check_cache_in_idle==1) || \
(env->src_rq->rt.rt_nr_running==0) || \
(pulled>0)))
#else
#define over_imbalance(lw, im) (((lw) / 2) > (im))
#endif
/*
* move_tasks tries to move up to imbalance weighted load from busiest to
* this_rq, as part of a balancing operation within domain "sd".
* Returns 1 if successful and 0 otherwise.
*
* Called with both runqueues locked.
*/
static int move_tasks(struct lb_env *env)
{
struct list_head *tasks = &env->src_rq->cfs_tasks;
struct task_struct *p;
unsigned long load;
int pulled = 0;
if (env->imbalance <= 0)
return 0;
mt_sched_printf("move_tasks start ");
while (!list_empty(tasks)) {
p = list_first_entry(tasks, struct task_struct, se.group_node);
env->loop++;
/* We've more or less seen every task there is, call it quits */
if (env->loop > env->loop_max)
break;
/* take a breather every nr_migrate tasks */
if (env->loop > env->loop_break) {
env->loop_break += sched_nr_migrate_break;
env->flags |= LBF_NEED_BREAK;
break;
}
#if defined (CONFIG_MTK_SCHED_CMP_LAZY_BALANCE) && !defined(CONFIG_HMP_LAZY_BALANCE)
if(need_lazy_balance(env->dst_cpu, env->src_cpu, p))
goto next;
#endif
if (!can_migrate_task(p, env))
goto next;
load = task_h_load(p);
if (sched_feat(LB_MIN) && load < 16 && !env->sd->nr_balance_failed)
goto next;
if (over_imbalance(load, env->imbalance))
{
goto next;
}
move_task(p, env);
pulled++;
env->imbalance -= load;
#ifdef CONFIG_PREEMPT
/*
* NEWIDLE balancing is a source of latency, so preemptible
* kernels will stop after the first task is pulled to minimize
* the critical section.
*/
if (env->idle == CPU_NEWLY_IDLE)
break;
#endif
/*
* We only want to steal up to the prescribed amount of
* weighted load.
*/
if (env->imbalance <= 0)
break;
continue;
next:
list_move_tail(&p->se.group_node, tasks);
}
/*
* Right now, this is one of only two places move_task() is called,
* so we can safely collect move_task() stats here rather than
* inside move_task().
*/
schedstat_add(env->sd, lb_gained[env->idle], pulled);
mt_sched_printf("move_tasks end");
return pulled;
}
#ifdef CONFIG_MTK_SCHED_CMP
#ifdef CONFIG_MTK_SCHED_CMP_TGS
static int cmp_can_migrate_task(struct task_struct *p, struct lb_env *env)
{
struct sched_domain *sd = env->sd;
BUG_ON(sd == NULL);
if (!(sd->flags & SD_BALANCE_TG))
return 0;
if (arch_is_multi_cluster()) {
int src_clid, dst_clid;
int src_nr_cpus;
struct thread_group_info_t *src_tginfo, *dst_tginfo;
src_clid = get_cluster_id(env->src_cpu);
dst_clid = get_cluster_id(env->dst_cpu);
BUG_ON(dst_clid == -1 || src_clid == -1);
BUG_ON(p == NULL || p->group_leader == NULL);
src_tginfo = &p->group_leader->thread_group_info[src_clid];
dst_tginfo = &p->group_leader->thread_group_info[dst_clid];
src_nr_cpus = nr_cpus_in_cluster(src_clid, false);
#ifdef CONFIG_MT_SCHED_INFO
mt_sched_printf("check rule0: pid=%d comm=%s load=%ld src:clid=%d tginfo->nr_running=%ld nr_cpus=%d load_avg_ratio=%ld",
p->pid, p->comm, p->se.avg.load_avg_ratio,
src_clid, src_tginfo->nr_running, src_nr_cpus,
src_tginfo->load_avg_ratio);
#endif
#ifdef CONFIG_MTK_SCHED_CMP_TGS_WAKEUP
if ( (!thread_group_empty(p)) &&
(src_tginfo->nr_running <= src_nr_cpus) &&
(src_tginfo->nr_running > dst_tginfo->nr_running)){
mt_sched_printf("hit ruleA: bypass pid=%d comm=%s src:nr_running=%lu nr_cpus=%d dst:nr_running=%lu",
p->pid, p->comm, src_tginfo->nr_running, src_nr_cpus, dst_tginfo->nr_running);
return 0;
}
#endif
}
return 1;
}
static int need_migrate_task_immediately(struct task_struct *p,
struct lb_env *env, struct clb_env *clbenv)
{
struct sched_domain *sd = env->sd;
BUG_ON(sd == NULL);
if (arch_is_big_little()) {
mt_sched_printf("[%s] b.L arch", __func__);
#ifdef CONFIG_MT_SCHED_INFO
mt_sched_printf("check rule0: pid=%d comm=%s src=%d dst=%d p->prio=%d p->se.avg.load_avg_ratio=%ld",
p->pid, p->comm, env->src_cpu, env->dst_cpu, p->prio, p->se.avg.load_avg_ratio);
#endif
/* from LITTLE to big */
if (arch_cpu_is_little(env->src_cpu) && arch_cpu_is_big(env->dst_cpu)) {
BUG_ON(env->src_cpu != clbenv->ltarget);
if (p->se.avg.load_avg_ratio >= clbenv->bstats.threshold)
return 1;
/* from big to LITTLE */
} else if (arch_cpu_is_big(env->src_cpu) && arch_cpu_is_little(env->dst_cpu)) {
BUG_ON(env->src_cpu != clbenv->btarget);
if (p->se.avg.load_avg_ratio < clbenv->lstats.threshold)
return 1;
}
return 0;
}
if (arch_is_multi_cluster() && (sd->flags & SD_BALANCE_TG)) {
int src_clid, dst_clid;
int src_nr_cpus;
struct thread_group_info_t *src_tginfo, *dst_tginfo;
src_clid = get_cluster_id(env->src_cpu);
dst_clid = get_cluster_id(env->dst_cpu);
BUG_ON(dst_clid == -1 || src_clid == -1);
BUG_ON(p == NULL || p->group_leader == NULL);
src_tginfo = &p->group_leader->thread_group_info[src_clid];
dst_tginfo = &p->group_leader->thread_group_info[dst_clid];
src_nr_cpus = nr_cpus_in_cluster(src_clid, false);
mt_sched_printf("[%s] L.L arch", __func__);
if ((p->se.avg.load_avg_ratio*4 >= NICE_0_LOAD*3) &&
src_tginfo->nr_running > src_nr_cpus &&
src_tginfo->load_avg_ratio*10 > NICE_0_LOAD*src_nr_cpus*9) {
//pr_warn("[%s] hit rule0, candidate_load_move/load_move (%ld/%ld)\n",
// __func__, candidate_load_move, env->imbalance);
return 1;
}
}
return 0;
}
#endif
/*
* move_tasks tries to move up to load_move weighted load from busiest to
* this_rq, as part of a balancing operation within domain "sd".
* Returns 1 if successful and 0 otherwise.
*
* Called with both runqueues locked.
*/
static int cmp_move_tasks(struct sched_domain *sd, struct lb_env *env)
{
struct list_head *tasks = &env->src_rq->cfs_tasks;
struct task_struct *p;
unsigned long load = 0;
int pulled = 0;
long tg_load_move, other_load_move;
struct list_head tg_tasks, other_tasks;
int src_clid, dst_clid;
#ifdef CONFIG_MTK_SCHED_CMP_TGS_WAKEUP
struct cpumask tmp, *cpus = &tmp;
#endif
#ifdef MTK_QUICK
int flag = 0;
#endif
struct clb_env clbenv;
struct cpumask srcmask, dstmask;
if (env->imbalance <= 0)
return 0;
other_load_move = env->imbalance;
INIT_LIST_HEAD(&other_tasks);
// if (sd->flags & SD_BALANCE_TG) {
tg_load_move = env->imbalance;
INIT_LIST_HEAD(&tg_tasks);
src_clid = get_cluster_id(env->src_cpu);
dst_clid = get_cluster_id(env->dst_cpu);
BUG_ON(dst_clid == -1 || src_clid == -1);
#ifdef CONFIG_MTK_SCHED_CMP_TGS_WAKEUP
get_cluster_cpus(cpus, src_clid, true);
#endif
mt_sched_printf("move_tasks_tg start: src:cpu=%d clid=%d runnable_load=%lu dst:cpu=%d clid=%d runnable_load=%lu imbalance=%ld curr->on_rq=%d",
env->src_cpu, src_clid, cpu_rq(env->src_cpu)->cfs.runnable_load_avg,
env->dst_cpu, dst_clid, cpu_rq(env->dst_cpu)->cfs.runnable_load_avg,
env->imbalance, env->dst_rq->curr->on_rq);
// }
mt_sched_printf("max=%d busiest->nr_running=%d",
env->loop_max, cpu_rq(env->src_cpu)->nr_running);
if (arch_is_big_little()) {
get_cluster_cpus(&srcmask, src_clid, true);
get_cluster_cpus(&dstmask, dst_clid, true);
memset(&clbenv, 0, sizeof(clbenv));
clbenv.flags |= HMP_LB;
clbenv.ltarget = arch_cpu_is_little(env->src_cpu) ? env->src_cpu : env->dst_cpu;
clbenv.btarget = arch_cpu_is_big(env->src_cpu) ? env->src_cpu : env->dst_cpu;
clbenv.lcpus = arch_cpu_is_little(env->src_cpu) ? &srcmask : &dstmask;
clbenv.bcpus = arch_cpu_is_big(env->src_cpu) ? &srcmask : &dstmask;
sched_update_clbstats(&clbenv);
}
while (!list_empty(tasks)) {
struct thread_group_info_t *src_tginfo, *dst_tginfo;
p = list_first_entry(tasks, struct task_struct, se.group_node);
#ifdef CONFIG_MT_SCHED_INFO
mt_sched_printf("check: pid=%d comm=%s load_avg_contrib=%lu h_load=%lu runnable_load_avg=%lu loop=%d, env->imbalance=%ld tg_load_move=%ld",
p->pid, p->comm, p->se.avg.load_avg_contrib,
task_cfs_rq(p)->h_load, task_cfs_rq(p)->runnable_load_avg,
env->loop, env->imbalance, tg_load_move);
#endif
env->loop++;
/* We've more or less seen every task there is, call it quits */
if (env->loop > env->loop_max)
break;
#if 0 // TO check
/* take a breather every nr_migrate tasks */
if (env->loop > env->loop_break) {
env->loop_break += sched_nr_migrate_break;
env->flags |= LBF_NEED_BREAK;
break;
}
#endif
BUG_ON(p == NULL || p->group_leader == NULL);
src_tginfo = &p->group_leader->thread_group_info[src_clid];
dst_tginfo = &p->group_leader->thread_group_info[dst_clid];
/* rule0 */
if (!can_migrate_task(p, env)) {
mt_sched_printf("can not migrate: pid=%d comm=%s",
p->pid, p->comm);
goto next;
}
load = task_h_load(p);
if (sched_feat(LB_MIN) && load < 16 && !env->sd->nr_balance_failed) {
mt_sched_printf("can not migrate: pid=%d comm=%s sched_feat",
p->pid, p->comm );
goto next;
}
if (over_imbalance(load, env->imbalance)) {
mt_sched_printf("can not migrate: pid=%d comm=%s load=%ld imbalance=%ld",
p->pid, p->comm, load, env->imbalance );
goto next;
}
/* meet rule0 , migrate immediately */
if (need_migrate_task_immediately(p, env, &clbenv)) {
pulled++;
env->imbalance -= load;
tg_load_move -= load;
other_load_move -= load;
mt_sched_printf("hit rule0: pid=%d comm=%s load=%ld imbalance=%ld tg_imbalance=%ld other_load_move=%ld",
p->pid, p->comm, load, env->imbalance, tg_load_move, other_load_move);
move_task(p, env);
if (env->imbalance <= 0)
break;
continue;
}
/* for TGS */
if (!cmp_can_migrate_task(p, env))
goto next;
if (sd->flags & SD_BALANCE_TG){
if (over_imbalance(load, tg_load_move)) {
mt_sched_printf("can not migrate: pid=%d comm=%s load=%ld imbalance=%ld",
p->pid, p->comm, load, tg_load_move );
goto next;
}
#ifdef MTK_QUICK
if (candidate_load_move <= 0) {
mt_sched_printf("check: pid=%d comm=%s candidate_load_move=%d",
p->pid, p->comm, candidate_load_move);
goto next;
}
#endif
/* rule1, single thread */
#ifdef CONFIG_MT_SCHED_INFO
mt_sched_printf("check rule1: pid=%d p->comm=%s thread_group_cnt=%lu thread_group_empty(p)=%d",
p->pid, p->comm,
p->group_leader->thread_group_info[0].nr_running +
p->group_leader->thread_group_info[1].nr_running,
thread_group_empty(p));
#endif
if (thread_group_empty(p)) {
list_move_tail(&p->se.group_node, &tg_tasks);
tg_load_move -= load;
other_load_move -= load;
mt_sched_printf("hit rule1: pid=%d p->comm=%s load=%ld tg_imbalance=%ld",
p->pid, p->comm, load, tg_load_move);
continue;
}
/* rule2 */
#ifdef CONFIG_MT_SCHED_INFO
mt_sched_printf("check rule2: pid=%d p->comm=%s %ld, %ld, %ld, %ld, %ld",
p->pid, p->comm, src_tginfo->nr_running, src_tginfo->cfs_nr_running, dst_tginfo->nr_running,
p->se.avg.load_avg_ratio, src_tginfo->load_avg_ratio);
#endif
if ((src_tginfo->nr_running < dst_tginfo->nr_running) &&
((p->se.avg.load_avg_ratio * src_tginfo->cfs_nr_running) <=
src_tginfo->load_avg_ratio)) {
list_move_tail(&p->se.group_node, &tg_tasks);
tg_load_move -= load;
other_load_move -= load;
mt_sched_printf("hit rule2: pid=%d p->comm=%s load=%ld tg_imbalance=%ld",
p->pid, p->comm, load, tg_load_move);
continue;
}
if (over_imbalance(load, other_load_move))
goto next;
/*
if (other_load_move <= 0)
goto next;
*/
list_move_tail(&p->se.group_node, &other_tasks);
other_load_move -= load;
continue;
}else{
list_move_tail(&p->se.group_node, &other_tasks);
other_load_move -= load;
continue;
}
// ytchang
#if defined (CONFIG_MTK_SCHED_CMP_LAZY_BALANCE) && !defined(CONFIG_HMP_LAZY_BALANCE)
if(need_lazy_balance(env->dst_cpu, env->src_cpu, p))
goto next;
#endif
next:
/* original rule */
list_move_tail(&p->se.group_node, tasks);
} // end of while()
if ( sd->flags & SD_BALANCE_TG){
while (!list_empty(&tg_tasks)) {
p = list_first_entry(&tg_tasks, struct task_struct, se.group_node);
list_move_tail(&p->se.group_node, tasks);
if (env->imbalance > 0) {
load = task_h_load(p);
if (over_imbalance(load, env->imbalance)){
mt_sched_printf("overload rule1,2: pid=%d p->comm=%s load=%ld imbalance=%ld",
p->pid, p->comm, load, env->imbalance);
#ifdef MTK_QUICK
flag=1;
#endif
continue;
}
move_task(p, env);
env->imbalance -= load;
pulled++;
mt_sched_printf("migrate hit rule1,2: pid=%d p->comm=%s load=%ld imbalance=%ld",
p->pid, p->comm, load, env->imbalance);
}
}
}
mt_sched_printf("move_tasks_tg finish rule migrate");
while (!list_empty(&other_tasks)) {
p = list_first_entry(&other_tasks, struct task_struct, se.group_node);
list_move_tail(&p->se.group_node, tasks);
#ifdef MTK_QUICK
if (!flag && (env->imbalance > 0)) {
#else
if (env->imbalance > 0) {
#endif
load = task_h_load(p);
if (over_imbalance(load, env->imbalance)){
mt_sched_printf("overload others: pid=%d p->comm=%s load=%ld imbalance=%ld",
p->pid, p->comm, load, env->imbalance);
continue;
}
move_task(p, env);
env->imbalance -= load;
pulled++;
mt_sched_printf("migrate others: pid=%d p->comm=%s load=%ld imbalance=%ld",
p->pid, p->comm, load, env->imbalance);
}
}
/*
* Right now, this is one of only two places move_task() is called,
* so we can safely collect move_task() stats here rather than
* inside move_task().
*/
schedstat_add(env->sd, lb_gained[env->idle], pulled);
mt_sched_printf("move_tasks_tg finish pulled=%d imbalance=%ld", pulled, env->imbalance);
return pulled;
}
#endif /* CONFIG_MTK_SCHED_CMP */
#if defined (CONFIG_MTK_SCHED_CMP_LAZY_BALANCE) && !defined(CONFIG_HMP_LAZY_BALANCE)
static int need_lazy_balance(int dst_cpu, int src_cpu, struct task_struct *p)
{
/* Lazy balnace for small task
1. src cpu is buddy cpu
2. src cpu is not busy cpu
3. p is light task
*/
#ifdef CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER
if ( PA_ENABLE && cpumask_test_cpu(src_cpu, &buddy_cpu_map) &&
!is_buddy_busy(src_cpu) && is_light_task(p)) {
#else
if (cpumask_test_cpu(src_cpu, &buddy_cpu_map) &&
!is_buddy_busy(src_cpu) && is_light_task(p)) {
#endif
#ifdef CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER
unsigned int i;
AVOID_LOAD_BALANCE_FROM_CPUX_TO_CPUY_COUNT[src_cpu][dst_cpu]++;
mt_sched_printf("[PA]pid=%d, Lazy balance from CPU%d to CPU%d\n)\n", p->pid, src_cpu, dst_cpu);
for(i=0;i<4;i++) {
if(PA_MON_ENABLE && (strcmp(p->comm, &PA_MON[i][0]) == 0)) {
printk(KERN_EMERG "[PA] %s Lazy balance from CPU%d to CPU%d\n", p->comm, src_cpu, dst_cpu);
// printk(KERN_EMERG "[PA] src_cpu RQ Usage = %u, Period = %u, NR = %u\n",
// per_cpu(BUDDY_CPU_RQ_USAGE, src_cpu),
// per_cpu(BUDDY_CPU_RQ_PERIOD, src_cpu),
// per_cpu(BUDDY_CPU_RQ_NR, src_cpu));
// printk(KERN_EMERG "[PA] Task Usage = %u, Period = %u\n",
// p->se.avg.usage_avg_sum,
// p->se.avg.runnable_avg_period);
}
}
#endif
return 1;
}
else
return 0;
}
#endif
#ifdef CONFIG_FAIR_GROUP_SCHED
/*
* update tg->load_weight by folding this cpu's load_avg
*/
static void __update_blocked_averages_cpu(struct task_group *tg, int cpu)
{
struct sched_entity *se = tg->se[cpu];
struct cfs_rq *cfs_rq = tg->cfs_rq[cpu];
/* throttled entities do not contribute to load */
if (throttled_hierarchy(cfs_rq))
return;
update_cfs_rq_blocked_load(cfs_rq, 1);
if (se) {
update_entity_load_avg(se, 1);
/*
* We pivot on our runnable average having decayed to zero for
* list removal. This generally implies that all our children
* have also been removed (modulo rounding error or bandwidth
* control); however, such cases are rare and we can fix these
* at enqueue.
*
* TODO: fix up out-of-order children on enqueue.
*/
if (!se->avg.runnable_avg_sum && !cfs_rq->nr_running)
list_del_leaf_cfs_rq(cfs_rq);
} else {
struct rq *rq = rq_of(cfs_rq);
update_rq_runnable_avg(rq, rq->nr_running);
}
}
static void update_blocked_averages(int cpu)
{
struct rq *rq = cpu_rq(cpu);
struct cfs_rq *cfs_rq;
unsigned long flags;
raw_spin_lock_irqsave(&rq->lock, flags);
update_rq_clock(rq);
/*
* Iterates the task_group tree in a bottom up fashion, see
* list_add_leaf_cfs_rq() for details.
*/
for_each_leaf_cfs_rq(rq, cfs_rq) {
/*
* Note: We may want to consider periodically releasing
* rq->lock about these updates so that creating many task
* groups does not result in continually extending hold time.
*/
__update_blocked_averages_cpu(cfs_rq->tg, rq->cpu);
}
raw_spin_unlock_irqrestore(&rq->lock, flags);
}
/*
* Compute the cpu's hierarchical load factor for each task group.
* This needs to be done in a top-down fashion because the load of a child
* group is a fraction of its parents load.
*/
static int tg_load_down(struct task_group *tg, void *data)
{
unsigned long load;
long cpu = (long)data;
if (!tg->parent) {
/*
* rq's sched_avg is not updated accordingly. adopt rq's
* corresponding cfs_rq runnable loading instead.
*
* a003a25b sched: Consider runnable load average...
*
load = cpu_rq(cpu)->avg.load_avg_contrib;
*/
load = cpu_rq(cpu)->cfs.runnable_load_avg;
} else {
load = tg->parent->cfs_rq[cpu]->h_load;
load = div64_ul(load * tg->se[cpu]->avg.load_avg_contrib,
tg->parent->cfs_rq[cpu]->runnable_load_avg + 1);
}
tg->cfs_rq[cpu]->h_load = load;
return 0;
}
static void update_h_load(long cpu)
{
rcu_read_lock();
walk_tg_tree(tg_load_down, tg_nop, (void *)cpu);
rcu_read_unlock();
}
static unsigned long task_h_load(struct task_struct *p)
{
struct cfs_rq *cfs_rq = task_cfs_rq(p);
return div64_ul(p->se.avg.load_avg_contrib * cfs_rq->h_load,
cfs_rq->runnable_load_avg + 1);
}
#else
static inline void update_blocked_averages(int cpu)
{
}
static inline void update_h_load(long cpu)
{
}
static unsigned long task_h_load(struct task_struct *p)
{
return p->se.avg.load_avg_contrib;
}
#endif
/********** Helpers for find_busiest_group ************************/
/*
* sd_lb_stats - Structure to store the statistics of a sched_domain
* during load balancing.
*/
struct sd_lb_stats {
struct sched_group *busiest; /* Busiest group in this sd */
struct sched_group *this; /* Local group in this sd */
unsigned long total_load; /* Total load of all groups in sd */
unsigned long total_pwr; /* Total power of all groups in sd */
unsigned long avg_load; /* Average load across all groups in sd */
/** Statistics of this group */
unsigned long this_load;
unsigned long this_load_per_task;
unsigned long this_nr_running;
unsigned long this_has_capacity;
unsigned int this_idle_cpus;
/* Statistics of the busiest group */
unsigned int busiest_idle_cpus;
unsigned long max_load;
unsigned long busiest_load_per_task;
unsigned long busiest_nr_running;
unsigned long busiest_group_capacity;
unsigned long busiest_has_capacity;
unsigned int busiest_group_weight;
int group_imb; /* Is there imbalance in this sd */
};
/*
* sg_lb_stats - stats of a sched_group required for load_balancing
*/
struct sg_lb_stats {
unsigned long avg_load; /*Avg load across the CPUs of the group */
unsigned long group_load; /* Total load over the CPUs of the group */
unsigned long sum_nr_running; /* Nr tasks running in the group */
unsigned long sum_weighted_load; /* Weighted load of group's tasks */
unsigned long group_capacity;
unsigned long idle_cpus;
unsigned long group_weight;
int group_imb; /* Is there an imbalance in the group ? */
int group_has_capacity; /* Is there extra capacity in the group? */
};
/**
* get_sd_load_idx - Obtain the load index for a given sched domain.
* @sd: The sched_domain whose load_idx is to be obtained.
* @idle: The Idle status of the CPU for whose sd load_icx is obtained.
*/
static inline int get_sd_load_idx(struct sched_domain *sd,
enum cpu_idle_type idle)
{
int load_idx;
switch (idle) {
case CPU_NOT_IDLE:
load_idx = sd->busy_idx;
break;
case CPU_NEWLY_IDLE:
load_idx = sd->newidle_idx;
break;
default:
load_idx = sd->idle_idx;
break;
}
return load_idx;
}
static unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu)
{
return SCHED_POWER_SCALE;
}
unsigned long __weak arch_scale_freq_power(struct sched_domain *sd, int cpu)
{
return default_scale_freq_power(sd, cpu);
}
static unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu)
{
unsigned long weight = sd->span_weight;
unsigned long smt_gain = sd->smt_gain;
smt_gain /= weight;
return smt_gain;
}
unsigned long __weak arch_scale_smt_power(struct sched_domain *sd, int cpu)
{
return default_scale_smt_power(sd, cpu);
}
static unsigned long scale_rt_power(int cpu)
{
struct rq *rq = cpu_rq(cpu);
u64 total, available, age_stamp, avg;
/*
* Since we're reading these variables without serialization make sure
* we read them once before doing sanity checks on them.
*/
age_stamp = ACCESS_ONCE(rq->age_stamp);
avg = ACCESS_ONCE(rq->rt_avg);
total = sched_avg_period() + (rq->clock - age_stamp);
if (unlikely(total < avg)) {
/* Ensures that power won't end up being negative */
available = 0;
} else {
available = total - avg;
}
if (unlikely((s64)total < SCHED_POWER_SCALE))
total = SCHED_POWER_SCALE;
total >>= SCHED_POWER_SHIFT;
return div_u64(available, total);
}
static void update_cpu_power(struct sched_domain *sd, int cpu)
{
unsigned long weight = sd->span_weight;
unsigned long power = SCHED_POWER_SCALE;
struct sched_group *sdg = sd->groups;
if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) {
if (sched_feat(ARCH_POWER))
power *= arch_scale_smt_power(sd, cpu);
else
power *= default_scale_smt_power(sd, cpu);
power >>= SCHED_POWER_SHIFT;
}
sdg->sgp->power_orig = power;
if (sched_feat(ARCH_POWER))
power *= arch_scale_freq_power(sd, cpu);
else
power *= default_scale_freq_power(sd, cpu);
power >>= SCHED_POWER_SHIFT;
power *= scale_rt_power(cpu);
power >>= SCHED_POWER_SHIFT;
if (!power)
power = 1;
cpu_rq(cpu)->cpu_power = power;
sdg->sgp->power = power;
}
void update_group_power(struct sched_domain *sd, int cpu)
{
struct sched_domain *child = sd->child;
struct sched_group *group, *sdg = sd->groups;
unsigned long power;
unsigned long interval;
interval = msecs_to_jiffies(sd->balance_interval);
interval = clamp(interval, 1UL, max_load_balance_interval);
sdg->sgp->next_update = jiffies + interval;
if (!child) {
update_cpu_power(sd, cpu);
return;
}
power = 0;
if (child->flags & SD_OVERLAP) {
/*
* SD_OVERLAP domains cannot assume that child groups
* span the current group.
*/
for_each_cpu(cpu, sched_group_cpus(sdg))
power += power_of(cpu);
} else {
/*
* !SD_OVERLAP domains can assume that child groups
* span the current group.
*/
group = child->groups;
do {
power += group->sgp->power;
group = group->next;
} while (group != child->groups);
}
sdg->sgp->power_orig = sdg->sgp->power = power;
}
/*
* Try and fix up capacity for tiny siblings, this is needed when
* things like SD_ASYM_PACKING need f_b_g to select another sibling
* which on its own isn't powerful enough.
*
* See update_sd_pick_busiest() and check_asym_packing().
*/
static inline int
fix_small_capacity(struct sched_domain *sd, struct sched_group *group)
{
/*
* Only siblings can have significantly less than SCHED_POWER_SCALE
*/
if (!(sd->flags & SD_SHARE_CPUPOWER))
return 0;
/*
* If ~90% of the cpu_power is still there, we're good.
*/
if (group->sgp->power * 32 > group->sgp->power_orig * 29)
return 1;
return 0;
}
/**
* update_sg_lb_stats - Update sched_group's statistics for load balancing.
* @env: The load balancing environment.
* @group: sched_group whose statistics are to be updated.
* @load_idx: Load index of sched_domain of this_cpu for load calc.
* @local_group: Does group contain this_cpu.
* @balance: Should we balance.
* @sgs: variable to hold the statistics for this group.
*/
static inline void update_sg_lb_stats(struct lb_env *env,
struct sched_group *group, int load_idx,
int local_group, int *balance, struct sg_lb_stats *sgs)
{
unsigned long nr_running, max_nr_running, min_nr_running;
unsigned long load, max_cpu_load, min_cpu_load;
unsigned int balance_cpu = -1, first_idle_cpu = 0;
unsigned long avg_load_per_task = 0;
int i;
if (local_group)
balance_cpu = group_balance_cpu(group);
/* Tally up the load of all CPUs in the group */
max_cpu_load = 0;
min_cpu_load = ~0UL;
max_nr_running = 0;
min_nr_running = ~0UL;
for_each_cpu_and(i, sched_group_cpus(group), env->cpus) {
struct rq *rq = cpu_rq(i);
nr_running = rq->nr_running;
/* Bias balancing toward cpus of our domain */
if (local_group) {
if (idle_cpu(i) && !first_idle_cpu &&
cpumask_test_cpu(i, sched_group_mask(group))) {
first_idle_cpu = 1;
balance_cpu = i;
}
load = target_load(i, load_idx);
} else {
load = source_load(i, load_idx);
if (load > max_cpu_load)
max_cpu_load = load;
if (min_cpu_load > load)
min_cpu_load = load;
if (nr_running > max_nr_running)
max_nr_running = nr_running;
if (min_nr_running > nr_running)
min_nr_running = nr_running;
#ifdef CONFIG_MT_LOAD_BALANCE_PROFILER
if((load_idx > 0) && (load == cpu_rq(i)->cpu_load[load_idx-1]))
mt_lbprof_stat_or(env->fail_reason, MT_LBPROF_HISTORY);
#endif
}
sgs->group_load += load;
sgs->sum_nr_running += nr_running;
sgs->sum_weighted_load += weighted_cpuload(i);
if (idle_cpu(i))
sgs->idle_cpus++;
}
/*
* First idle cpu or the first cpu(busiest) in this sched group
* is eligible for doing load balancing at this and above
* domains. In the newly idle case, we will allow all the cpu's
* to do the newly idle load balance.
*/
if (local_group) {
if (env->idle != CPU_NEWLY_IDLE) {
if (balance_cpu != env->dst_cpu) {
*balance = 0;
return;
}
update_group_power(env->sd, env->dst_cpu);
} else if (time_after_eq(jiffies, group->sgp->next_update))
update_group_power(env->sd, env->dst_cpu);
}
/* Adjust by relative CPU power of the group */
sgs->avg_load = (sgs->group_load*SCHED_POWER_SCALE) / group->sgp->power;
/*
* Consider the group unbalanced when the imbalance is larger
* than the average weight of a task.
*
* APZ: with cgroup the avg task weight can vary wildly and
* might not be a suitable number - should we keep a
* normalized nr_running number somewhere that negates
* the hierarchy?
*/
if (sgs->sum_nr_running)
avg_load_per_task = sgs->sum_weighted_load / sgs->sum_nr_running;
if ((max_cpu_load - min_cpu_load) >= avg_load_per_task &&
(max_nr_running - min_nr_running) > 1)
sgs->group_imb = 1;
sgs->group_capacity = DIV_ROUND_CLOSEST(group->sgp->power,
SCHED_POWER_SCALE);
if (!sgs->group_capacity)
sgs->group_capacity = fix_small_capacity(env->sd, group);
sgs->group_weight = group->group_weight;
if (sgs->group_capacity > sgs->sum_nr_running)
sgs->group_has_capacity = 1;
}
/**
* update_sd_pick_busiest - return 1 on busiest group
* @env: The load balancing environment.
* @sds: sched_domain statistics
* @sg: sched_group candidate to be checked for being the busiest
* @sgs: sched_group statistics
*
* Determine if @sg is a busier group than the previously selected
* busiest group.
*/
static bool update_sd_pick_busiest(struct lb_env *env,
struct sd_lb_stats *sds,
struct sched_group *sg,
struct sg_lb_stats *sgs)
{
if (sgs->avg_load <= sds->max_load) {
mt_lbprof_stat_or(env->fail_reason, MT_LBPROF_PICK_BUSIEST_FAIL_1);
return false;
}
if (sgs->sum_nr_running > sgs->group_capacity)
return true;
if (sgs->group_imb)
return true;
/*
* ASYM_PACKING needs to move all the work to the lowest
* numbered CPUs in the group, therefore mark all groups
* higher than ourself as busy.
*/
if ((env->sd->flags & SD_ASYM_PACKING) && sgs->sum_nr_running &&
env->dst_cpu < group_first_cpu(sg)) {
if (!sds->busiest)
return true;
if (group_first_cpu(sds->busiest) > group_first_cpu(sg))
return true;
}
mt_lbprof_stat_or(env->fail_reason, MT_LBPROF_PICK_BUSIEST_FAIL_2);
return false;
}
/**
* update_sd_lb_stats - Update sched_domain's statistics for load balancing.
* @env: The load balancing environment.
* @balance: Should we balance.
* @sds: variable to hold the statistics for this sched_domain.
*/
static inline void update_sd_lb_stats(struct lb_env *env,
int *balance, struct sd_lb_stats *sds)
{
struct sched_domain *child = env->sd->child;
struct sched_group *sg = env->sd->groups;
struct sg_lb_stats sgs;
int load_idx, prefer_sibling = 0;
if (child && child->flags & SD_PREFER_SIBLING)
prefer_sibling = 1;
load_idx = get_sd_load_idx(env->sd, env->idle);
do {
int local_group;
local_group = cpumask_test_cpu(env->dst_cpu, sched_group_cpus(sg));
memset(&sgs, 0, sizeof(sgs));
update_sg_lb_stats(env, sg, load_idx, local_group, balance, &sgs);
if (local_group && !(*balance))
return;
sds->total_load += sgs.group_load;
sds->total_pwr += sg->sgp->power;
/*
* In case the child domain prefers tasks go to siblings
* first, lower the sg capacity to one so that we'll try
* and move all the excess tasks away. We lower the capacity
* of a group only if the local group has the capacity to fit
* these excess tasks, i.e. nr_running < group_capacity. The
* extra check prevents the case where you always pull from the
* heaviest group when it is already under-utilized (possible
* with a large weight task outweighs the tasks on the system).
*/
if (prefer_sibling && !local_group && sds->this_has_capacity)
sgs.group_capacity = min(sgs.group_capacity, 1UL);
if (local_group) {
sds->this_load = sgs.avg_load;
sds->this = sg;
sds->this_nr_running = sgs.sum_nr_running;
sds->this_load_per_task = sgs.sum_weighted_load;
sds->this_has_capacity = sgs.group_has_capacity;
sds->this_idle_cpus = sgs.idle_cpus;
} else if (update_sd_pick_busiest(env, sds, sg, &sgs)) {
sds->max_load = sgs.avg_load;
sds->busiest = sg;
sds->busiest_nr_running = sgs.sum_nr_running;
sds->busiest_idle_cpus = sgs.idle_cpus;
sds->busiest_group_capacity = sgs.group_capacity;
sds->busiest_load_per_task = sgs.sum_weighted_load;
sds->busiest_has_capacity = sgs.group_has_capacity;
sds->busiest_group_weight = sgs.group_weight;
sds->group_imb = sgs.group_imb;
}
sg = sg->next;
} while (sg != env->sd->groups);
}
/**
* check_asym_packing - Check to see if the group is packed into the
* sched doman.
*
* This is primarily intended to used at the sibling level. Some
* cores like POWER7 prefer to use lower numbered SMT threads. In the
* case of POWER7, it can move to lower SMT modes only when higher
* threads are idle. When in lower SMT modes, the threads will
* perform better since they share less core resources. Hence when we
* have idle threads, we want them to be the higher ones.
*
* This packing function is run on idle threads. It checks to see if
* the busiest CPU in this domain (core in the P7 case) has a higher
* CPU number than the packing function is being run on. Here we are
* assuming lower CPU number will be equivalent to lower a SMT thread
* number.
*
* Returns 1 when packing is required and a task should be moved to
* this CPU. The amount of the imbalance is returned in *imbalance.
*
* @env: The load balancing environment.
* @sds: Statistics of the sched_domain which is to be packed
*/
static int check_asym_packing(struct lb_env *env, struct sd_lb_stats *sds)
{
int busiest_cpu;
if (!(env->sd->flags & SD_ASYM_PACKING))
return 0;
if (!sds->busiest)
return 0;
busiest_cpu = group_first_cpu(sds->busiest);
if (env->dst_cpu > busiest_cpu)
return 0;
env->imbalance = DIV_ROUND_CLOSEST(
sds->max_load * sds->busiest->sgp->power, SCHED_POWER_SCALE);
return 1;
}
/**
* fix_small_imbalance - Calculate the minor imbalance that exists
* amongst the groups of a sched_domain, during
* load balancing.
* @env: The load balancing environment.
* @sds: Statistics of the sched_domain whose imbalance is to be calculated.
*/
static inline
void fix_small_imbalance(struct lb_env *env, struct sd_lb_stats *sds)
{
unsigned long tmp, pwr_now = 0, pwr_move = 0;
unsigned int imbn = 2;
unsigned long scaled_busy_load_per_task;
if (sds->this_nr_running) {
sds->this_load_per_task /= sds->this_nr_running;
if (sds->busiest_load_per_task >
sds->this_load_per_task)
imbn = 1;
} else {
sds->this_load_per_task =
cpu_avg_load_per_task(env->dst_cpu);
}
scaled_busy_load_per_task = sds->busiest_load_per_task
* SCHED_POWER_SCALE;
scaled_busy_load_per_task /= sds->busiest->sgp->power;
if (sds->max_load - sds->this_load + scaled_busy_load_per_task >=
(scaled_busy_load_per_task * imbn)) {
env->imbalance = sds->busiest_load_per_task;
return;
}
/*
* OK, we don't have enough imbalance to justify moving tasks,
* however we may be able to increase total CPU power used by
* moving them.
*/
pwr_now += sds->busiest->sgp->power *
min(sds->busiest_load_per_task, sds->max_load);
pwr_now += sds->this->sgp->power *
min(sds->this_load_per_task, sds->this_load);
pwr_now /= SCHED_POWER_SCALE;
/* Amount of load we'd subtract */
tmp = (sds->busiest_load_per_task * SCHED_POWER_SCALE) /
sds->busiest->sgp->power;
if (sds->max_load > tmp)
pwr_move += sds->busiest->sgp->power *
min(sds->busiest_load_per_task, sds->max_load - tmp);
/* Amount of load we'd add */
if (sds->max_load * sds->busiest->sgp->power <
sds->busiest_load_per_task * SCHED_POWER_SCALE)
tmp = (sds->max_load * sds->busiest->sgp->power) /
sds->this->sgp->power;
else
tmp = (sds->busiest_load_per_task * SCHED_POWER_SCALE) /
sds->this->sgp->power;
pwr_move += sds->this->sgp->power *
min(sds->this_load_per_task, sds->this_load + tmp);
pwr_move /= SCHED_POWER_SCALE;
/* Move if we gain throughput */
if (pwr_move > pwr_now)
env->imbalance = sds->busiest_load_per_task;
}
/**
* calculate_imbalance - Calculate the amount of imbalance present within the
* groups of a given sched_domain during load balance.
* @env: load balance environment
* @sds: statistics of the sched_domain whose imbalance is to be calculated.
*/
static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *sds)
{
unsigned long max_pull, load_above_capacity = ~0UL;
sds->busiest_load_per_task /= sds->busiest_nr_running;
if (sds->group_imb) {
sds->busiest_load_per_task =
min(sds->busiest_load_per_task, sds->avg_load);
}
/*
* In the presence of smp nice balancing, certain scenarios can have
* max load less than avg load(as we skip the groups at or below
* its cpu_power, while calculating max_load..)
*/
if (sds->max_load < sds->avg_load) {
env->imbalance = 0;
return fix_small_imbalance(env, sds);
}
if (!sds->group_imb) {
/*
* Don't want to pull so many tasks that a group would go idle.
*/
load_above_capacity = (sds->busiest_nr_running -
sds->busiest_group_capacity);
load_above_capacity *= (SCHED_LOAD_SCALE * SCHED_POWER_SCALE);
load_above_capacity /= sds->busiest->sgp->power;
}
/*
* We're trying to get all the cpus to the average_load, so we don't
* want to push ourselves above the average load, nor do we wish to
* reduce the max loaded cpu below the average load. At the same time,
* we also don't want to reduce the group load below the group capacity
* (so that we can implement power-savings policies etc). Thus we look
* for the minimum possible imbalance.
* Be careful of negative numbers as they'll appear as very large values
* with unsigned longs.
*/
max_pull = min(sds->max_load - sds->avg_load, load_above_capacity);
/* How much load to actually move to equalise the imbalance */
env->imbalance = min(max_pull * sds->busiest->sgp->power,
(sds->avg_load - sds->this_load) * sds->this->sgp->power)
/ SCHED_POWER_SCALE;
/*
* if *imbalance is less than the average load per runnable task
* there is no guarantee that any tasks will be moved so we'll have
* a think about bumping its value to force at least one task to be
* moved
*/
if (env->imbalance < sds->busiest_load_per_task)
return fix_small_imbalance(env, sds);
}
/******* find_busiest_group() helpers end here *********************/
/**
* find_busiest_group - Returns the busiest group within the sched_domain
* if there is an imbalance. If there isn't an imbalance, and
* the user has opted for power-savings, it returns a group whose
* CPUs can be put to idle by rebalancing those tasks elsewhere, if
* such a group exists.
*
* Also calculates the amount of weighted load which should be moved
* to restore balance.
*
* @env: The load balancing environment.
* @balance: Pointer to a variable indicating if this_cpu
* is the appropriate cpu to perform load balancing at this_level.
*
* Returns: - the busiest group if imbalance exists.
* - If no imbalance and user has opted for power-savings balance,
* return the least loaded group whose CPUs can be
* put to idle by rebalancing its tasks onto our group.
*/
static struct sched_group *
find_busiest_group(struct lb_env *env, int *balance)
{
struct sd_lb_stats sds;
memset(&sds, 0, sizeof(sds));
/*
* Compute the various statistics relavent for load balancing at
* this level.
*/
update_sd_lb_stats(env, balance, &sds);
/*
* this_cpu is not the appropriate cpu to perform load balancing at
* this level.
*/
if (!(*balance)){
mt_lbprof_stat_or(env->fail_reason, MT_LBPROF_BALANCE);
goto ret;
}
if ((env->idle == CPU_IDLE || env->idle == CPU_NEWLY_IDLE) &&
check_asym_packing(env, &sds))
return sds.busiest;
/* There is no busy sibling group to pull tasks from */
if (!sds.busiest || sds.busiest_nr_running == 0){
if(!sds.busiest){
mt_lbprof_stat_or(env->fail_reason, MT_LBPROF_NOBUSYG_BUSIEST_NO_TASK);
}else{
mt_lbprof_stat_or(env->fail_reason, MT_LBPROF_NOBUSYG_NO_BUSIEST);
}
goto out_balanced;
}
sds.avg_load = (SCHED_POWER_SCALE * sds.total_load) / sds.total_pwr;
/*
* If the busiest group is imbalanced the below checks don't
* work because they assumes all things are equal, which typically
* isn't true due to cpus_allowed constraints and the like.
*/
if (sds.group_imb)
goto force_balance;
/* SD_BALANCE_NEWIDLE trumps SMP nice when underutilized */
if (env->idle == CPU_NEWLY_IDLE && sds.this_has_capacity &&
!sds.busiest_has_capacity)
goto force_balance;
/*
* If the local group is more busy than the selected busiest group
* don't try and pull any tasks.
*/
if (sds.this_load >= sds.max_load){
mt_lbprof_stat_or(env->fail_reason, MT_LBPROF_NOBUSYG_NO_LARGER_THAN);
goto out_balanced;
}
/*
* Don't pull any tasks if this group is already above the domain
* average load.
*/
if (sds.this_load >= sds.avg_load){
mt_lbprof_stat_or(env->fail_reason, MT_LBPROF_NOBUSYG_NO_LARGER_THAN);
goto out_balanced;
}
if (env->idle == CPU_IDLE) {
/*
* This cpu is idle. If the busiest group load doesn't
* have more tasks than the number of available cpu's and
* there is no imbalance between this and busiest group
* wrt to idle cpu's, it is balanced.
*/
if ((sds.this_idle_cpus <= sds.busiest_idle_cpus + 1) &&
sds.busiest_nr_running <= sds.busiest_group_weight)
goto out_balanced;
} else {
/*
* In the CPU_NEWLY_IDLE, CPU_NOT_IDLE cases, use
* imbalance_pct to be conservative.
*/
if (100 * sds.max_load <= env->sd->imbalance_pct * sds.this_load){
mt_lbprof_stat_or(env->fail_reason, MT_LBPROF_NOBUSYG_CHECK_FAIL);
goto out_balanced;
}
}
force_balance:
/* Looks like there is an imbalance. Compute it */
calculate_imbalance(env, &sds);
return sds.busiest;
out_balanced:
ret:
env->imbalance = 0;
return NULL;
}
/*
* find_busiest_queue - find the busiest runqueue among the cpus in group.
*/
static struct rq *find_busiest_queue(struct lb_env *env,
struct sched_group *group)
{
struct rq *busiest = NULL, *rq;
unsigned long max_load = 0;
int i;
for_each_cpu(i, sched_group_cpus(group)) {
unsigned long power = power_of(i);
unsigned long capacity = DIV_ROUND_CLOSEST(power,
SCHED_POWER_SCALE);
unsigned long wl;
if (!capacity)
capacity = fix_small_capacity(env->sd, group);
if (!cpumask_test_cpu(i, env->cpus))
continue;
rq = cpu_rq(i);
wl = weighted_cpuload(i);
/*
* When comparing with imbalance, use weighted_cpuload()
* which is not scaled with the cpu power.
*/
if (capacity && rq->nr_running == 1 && wl > env->imbalance)
continue;
/*
* For the load comparisons with the other cpu's, consider
* the weighted_cpuload() scaled with the cpu power, so that
* the load can be moved away from the cpu that is potentially
* running at a lower capacity.
*/
wl = (wl * SCHED_POWER_SCALE) / power;
if (wl > max_load) {
max_load = wl;
busiest = rq;
}
}
return busiest;
}
/*
* Max backoff if we encounter pinned tasks. Pretty arbitrary value, but
* so long as it is large enough.
*/
#define MAX_PINNED_INTERVAL 512
/* Working cpumask for load_balance and load_balance_newidle. */
DEFINE_PER_CPU(cpumask_var_t, load_balance_mask);
static int need_active_balance(struct lb_env *env)
{
struct sched_domain *sd = env->sd;
if (env->idle == CPU_NEWLY_IDLE) {
/*
* ASYM_PACKING needs to force migrate tasks from busy but
* higher numbered CPUs in order to pack all tasks in the
* lowest numbered CPUs.
*/
if ((sd->flags & SD_ASYM_PACKING) && env->src_cpu > env->dst_cpu)
return 1;
}
return unlikely(sd->nr_balance_failed > sd->cache_nice_tries+2);
}
static int active_load_balance_cpu_stop(void *data);
/*
* Check this_cpu to ensure it is balanced within domain. Attempt to move
* tasks if there is an imbalance.
*/
static int load_balance(int this_cpu, struct rq *this_rq,
struct sched_domain *sd, enum cpu_idle_type idle,
int *balance)
{
int ld_moved, cur_ld_moved, active_balance = 0;
struct sched_group *group;
struct rq *busiest;
unsigned long flags;
struct cpumask *cpus = __get_cpu_var(load_balance_mask);
struct lb_env env = {
.sd = sd,
.dst_cpu = this_cpu,
.dst_rq = this_rq,
.dst_grpmask = sched_group_cpus(sd->groups),
.idle = idle,
.loop_break = sched_nr_migrate_break,
.cpus = cpus,
#ifdef CONFIG_MT_LOAD_BALANCE_PROFILER
.fail_reason= MT_LBPROF_NO_TRIGGER,
#endif
};
/*
* For NEWLY_IDLE load_balancing, we don't need to consider
* other cpus in our group
*/
if (idle == CPU_NEWLY_IDLE)
env.dst_grpmask = NULL;
cpumask_copy(cpus, cpu_active_mask);
schedstat_inc(sd, lb_count[idle]);
redo:
group = find_busiest_group(&env, balance);
if (*balance == 0)
goto out_balanced;
if (!group) {
schedstat_inc(sd, lb_nobusyg[idle]);
if(mt_lbprof_test(env.fail_reason, MT_LBPROF_HISTORY)){
int tmp_cpu;
for_each_cpu(tmp_cpu, cpu_possible_mask){
if (tmp_cpu == this_rq->cpu)
continue;
mt_lbprof_update_state(tmp_cpu, MT_LBPROF_BALANCE_FAIL_STATE);
}
}
goto out_balanced;
}
busiest = find_busiest_queue(&env, group);
if (!busiest) {
schedstat_inc(sd, lb_nobusyq[idle]);
mt_lbprof_stat_or(env.fail_reason, MT_LBPROF_NOBUSYQ);
goto out_balanced;
}
#ifdef CONFIG_HMP_LAZY_BALANCE
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
if (PA_ENABLE && LB_ENABLE) {
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
if (per_cpu(sd_pack_buddy, this_cpu) == busiest->cpu && !is_buddy_busy(per_cpu(sd_pack_buddy, this_cpu))) {
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
AVOID_LOAD_BALANCE_FROM_CPUX_TO_CPUY_COUNT[this_cpu][busiest->cpu]++;
#ifdef CONFIG_HMP_TRACER
trace_sched_power_aware_active(POWER_AWARE_ACTIVE_MODULE_AVOID_BALANCE_FORM_CPUX_TO_CPUY, 0, this_cpu, busiest->cpu);
#endif /* CONFIG_HMP_TRACER */
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
schedstat_inc(sd, lb_nobusyq[idle]);
goto out_balanced;
}
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
}
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
#endif /* CONFIG_HMP_LAZY_BALANCE */
BUG_ON(busiest == env.dst_rq);
schedstat_add(sd, lb_imbalance[idle], env.imbalance);
ld_moved = 0;
if (busiest->nr_running > 1) {
/*
* Attempt to move tasks. If find_busiest_group has found
* an imbalance but busiest->nr_running <= 1, the group is
* still unbalanced. ld_moved simply stays zero, so it is
* correctly treated as an imbalance.
*/
env.flags |= LBF_ALL_PINNED;
env.src_cpu = busiest->cpu;
env.src_rq = busiest;
env.loop_max = min(sysctl_sched_nr_migrate, busiest->nr_running);
#ifdef CONFIG_MT_LOAD_BALANCE_ENHANCEMENT
env.mt_check_cache_in_idle = 1;
#endif
update_h_load(env.src_cpu);
more_balance:
local_irq_save(flags);
double_rq_lock(env.dst_rq, busiest);
#ifdef CONFIG_MTK_SCHED_CMP
env.loop_max = min_t(unsigned long, sysctl_sched_nr_migrate, busiest->nr_running);
mt_sched_printf("1 env.loop_max=%d, busiest->nr_running=%d src=%d, dst=%d, cpus_share_cache=%d",
env.loop_max, busiest->nr_running, env.src_cpu, env.dst_cpu, cpus_share_cache(env.src_cpu, env.dst_cpu));
#endif /* CONFIG_MTK_SCHED_CMP */
/*
* cur_ld_moved - load moved in current iteration
* ld_moved - cumulative load moved across iterations
*/
#ifdef CONFIG_MTK_SCHED_CMP
if (!cpus_share_cache(env.src_cpu, env.dst_cpu))
cur_ld_moved = cmp_move_tasks(sd, &env);
else
cur_ld_moved = move_tasks(&env);
#else /* !CONFIG_MTK_SCHED_CMP */
cur_ld_moved = move_tasks(&env);
#endif /* CONFIG_MTK_SCHED_CMP */
ld_moved += cur_ld_moved;
double_rq_unlock(env.dst_rq, busiest);
local_irq_restore(flags);
/*
* some other cpu did the load balance for us.
*/
if (cur_ld_moved && env.dst_cpu != smp_processor_id())
resched_cpu(env.dst_cpu);
if (env.flags & LBF_NEED_BREAK) {
env.flags &= ~LBF_NEED_BREAK;
goto more_balance;
}
/*
* Revisit (affine) tasks on src_cpu that couldn't be moved to
* us and move them to an alternate dst_cpu in our sched_group
* where they can run. The upper limit on how many times we
* iterate on same src_cpu is dependent on number of cpus in our
* sched_group.
*
* This changes load balance semantics a bit on who can move
* load to a given_cpu. In addition to the given_cpu itself
* (or a ilb_cpu acting on its behalf where given_cpu is
* nohz-idle), we now have balance_cpu in a position to move
* load to given_cpu. In rare situations, this may cause
* conflicts (balance_cpu and given_cpu/ilb_cpu deciding
* _independently_ and at _same_ time to move some load to
* given_cpu) causing exceess load to be moved to given_cpu.
* This however should not happen so much in practice and
* moreover subsequent load balance cycles should correct the
* excess load moved.
*/
if ((env.flags & LBF_SOME_PINNED) && env.imbalance > 0) {
env.dst_rq = cpu_rq(env.new_dst_cpu);
env.dst_cpu = env.new_dst_cpu;
env.flags &= ~LBF_SOME_PINNED;
env.loop = 0;
env.loop_break = sched_nr_migrate_break;
/* Prevent to re-select dst_cpu via env's cpus */
cpumask_clear_cpu(env.dst_cpu, env.cpus);
/*
* Go back to "more_balance" rather than "redo" since we
* need to continue with same src_cpu.
*/
goto more_balance;
}
/* All tasks on this runqueue were pinned by CPU affinity */
if (unlikely(env.flags & LBF_ALL_PINNED)) {
mt_lbprof_update_state(busiest->cpu, MT_LBPROF_ALLPINNED);
cpumask_clear_cpu(cpu_of(busiest), cpus);
if (!cpumask_empty(cpus)) {
env.loop = 0;
env.loop_break = sched_nr_migrate_break;
goto redo;
}
goto out_balanced;
}
#ifdef CONFIG_MT_LOAD_BALANCE_ENHANCEMENT
/* when move tasks fil, force migration no matter cache-hot */
/* use mt_check_cache_in_idle */
if (!ld_moved && ((CPU_NEWLY_IDLE == idle) || (CPU_IDLE == idle) ) ) {
#ifdef CONFIG_MT_LOAD_BALANCE_PROFILER
mt_lbprof_stat_set(env.fail_reason, MT_LBPROF_DO_LB);
#endif
env.mt_check_cache_in_idle = 0;
env.loop = 0;
local_irq_save(flags);
double_rq_lock(env.dst_rq, busiest);
#ifdef CONFIG_MTK_SCHED_CMP
env.loop_max = min_t(unsigned long, sysctl_sched_nr_migrate, busiest->nr_running);
mt_sched_printf("2 env.loop_max=%d, busiest->nr_running=%d",
env.loop_max, busiest->nr_running);
#endif /* CONFIG_MTK_SCHED_CMP */
if (!env.loop)
update_h_load(env.src_cpu);
#ifdef CONFIG_MTK_SCHED_CMP_TGS
if (!cpus_share_cache(env.src_cpu, env.dst_cpu))
ld_moved = cmp_move_tasks(sd, &env);
else{
ld_moved = move_tasks(&env);
}
#else /* !CONFIG_MTK_SCHED_CMP_TGS */
ld_moved = move_tasks(&env);
#endif /* CONFIG_MTK_SCHED_CMP_TGS */
double_rq_unlock(env.dst_rq, busiest);
local_irq_restore(flags);
/*
* some other cpu did the load balance for us.
*/
if (ld_moved && this_cpu != smp_processor_id())
resched_cpu(this_cpu);
}
#endif
}
if (!ld_moved) {
schedstat_inc(sd, lb_failed[idle]);
mt_lbprof_stat_or(env.fail_reason, MT_LBPROF_FAILED);
if ( mt_lbprof_test(env.fail_reason, MT_LBPROF_AFFINITY) ) {
mt_lbprof_update_state(busiest->cpu, MT_LBPROF_FAILURE_STATE);
}else if ( mt_lbprof_test(env.fail_reason, MT_LBPROF_CACHEHOT) ) {
mt_lbprof_update_state(busiest->cpu, MT_LBPROF_FAILURE_STATE);
}
/*
* Increment the failure counter only on periodic balance.
* We do not want newidle balance, which can be very
* frequent, pollute the failure counter causing
* excessive cache_hot migrations and active balances.
*/
if (idle != CPU_NEWLY_IDLE)
sd->nr_balance_failed++;
mt_lbprof_stat_inc(sd, mt_lbprof_nr_balance_failed);
if (need_active_balance(&env)) {
raw_spin_lock_irqsave(&busiest->lock, flags);
/* don't kick the active_load_balance_cpu_stop,
* if the curr task on busiest cpu can't be
* moved to this_cpu
*/
if (!cpumask_test_cpu(this_cpu,
tsk_cpus_allowed(busiest->curr))) {
raw_spin_unlock_irqrestore(&busiest->lock,
flags);
env.flags |= LBF_ALL_PINNED;
goto out_one_pinned;
}
/*
* ->active_balance synchronizes accesses to
* ->active_balance_work. Once set, it's cleared
* only after active load balance is finished.
*/
if (!busiest->active_balance) {
busiest->active_balance = 1;
busiest->push_cpu = this_cpu;
active_balance = 1;
}
raw_spin_unlock_irqrestore(&busiest->lock, flags);
if (active_balance) {
stop_one_cpu_nowait(cpu_of(busiest),
active_load_balance_cpu_stop, busiest,
&busiest->active_balance_work);
}
/*
* We've kicked active balancing, reset the failure
* counter.
*/
sd->nr_balance_failed = sd->cache_nice_tries+1;
}
} else
sd->nr_balance_failed = 0;
if (likely(!active_balance)) {
/* We were unbalanced, so reset the balancing interval */
sd->balance_interval = sd->min_interval;
} else {
/*
* If we've begun active balancing, start to back off. This
* case may not be covered by the all_pinned logic if there
* is only 1 task on the busy runqueue (because we don't call
* move_tasks).
*/
if (sd->balance_interval < sd->max_interval)
sd->balance_interval *= 2;
}
goto out;
out_balanced:
schedstat_inc(sd, lb_balanced[idle]);
sd->nr_balance_failed = 0;
mt_lbprof_stat_set(sd->mt_lbprof_nr_balance_failed, 0);
out_one_pinned:
/* tune up the balancing interval */
if (((env.flags & LBF_ALL_PINNED) &&
sd->balance_interval < MAX_PINNED_INTERVAL) ||
(sd->balance_interval < sd->max_interval))
sd->balance_interval *= 2;
ld_moved = 0;
out:
if (ld_moved){
mt_lbprof_stat_or(env.fail_reason, MT_LBPROF_SUCCESS);
mt_lbprof_stat_set(sd->mt_lbprof_nr_balance_failed, 0);
}
#ifdef CONFIG_MT_LOAD_BALANCE_PROFILER
if( CPU_NEWLY_IDLE == idle){
char strings[128]="";
snprintf(strings, 128, "%d:idle balance:%d:0x%x ", this_cpu, ld_moved, env.fail_reason);
mt_lbprof_rqinfo(strings);
trace_sched_lbprof_log(strings);
}else{
char strings[128]="";
snprintf(strings, 128, "%d:periodic balance:%d:0x%x ", this_cpu, ld_moved, env.fail_reason);
mt_lbprof_rqinfo(strings);
trace_sched_lbprof_log(strings);
}
#endif
return ld_moved;
}
/*
* idle_balance is called by schedule() if this_cpu is about to become
* idle. Attempts to pull tasks from other CPUs.
*/
void idle_balance(int this_cpu, struct rq *this_rq)
{
struct sched_domain *sd;
int pulled_task = 0;
unsigned long next_balance = jiffies + HZ;
#if defined(CONFIG_MT_LOAD_BALANCE_ENHANCEMENT) || defined(CONFIG_MT_LOAD_BALANCE_PROFILER)
unsigned long counter = 0;
#endif
this_rq->idle_stamp = this_rq->clock;
mt_lbprof_update_state_has_lock(this_cpu, MT_LBPROF_UPDATE_STATE);
#ifdef CONFIG_MT_LOAD_BALANCE_ENHANCEMENT
#ifdef CONFIG_LOCAL_TIMERS
counter = localtimer_get_counter();
if ( counter >= 260000 ) // 20ms
goto must_do;
if ( time_before(jiffies + 2, this_rq->next_balance) ) // 20ms
goto must_do;
#endif
#endif
if (this_rq->avg_idle < sysctl_sched_migration_cost){
#if defined(CONFIG_MT_LOAD_BALANCE_PROFILER)
char strings[128]="";
mt_lbprof_update_state_has_lock(this_cpu, MT_LBPROF_ALLOW_UNBLANCE_STATE);
snprintf(strings, 128, "%d:idle balance bypass: %llu %lu ", this_cpu, this_rq->avg_idle, counter);
mt_lbprof_rqinfo(strings);
trace_sched_lbprof_log(strings);
#endif
return;
}
#ifdef CONFIG_MT_LOAD_BALANCE_ENHANCEMENT
must_do:
#endif
/*
* Drop the rq->lock, but keep IRQ/preempt disabled.
*/
raw_spin_unlock(&this_rq->lock);
mt_lbprof_update_status();
update_blocked_averages(this_cpu);
rcu_read_lock();
for_each_domain(this_cpu, sd) {
unsigned long interval;
int balance = 1;
if (!(sd->flags & SD_LOAD_BALANCE))
continue;
if (sd->flags & SD_BALANCE_NEWIDLE) {
/* If we've pulled tasks over stop searching: */
pulled_task = load_balance(this_cpu, this_rq,
sd, CPU_NEWLY_IDLE, &balance);
}
interval = msecs_to_jiffies(sd->balance_interval);
if (time_after(next_balance, sd->last_balance + interval))
next_balance = sd->last_balance + interval;
if (pulled_task) {
this_rq->idle_stamp = 0;
break;
}
}
rcu_read_unlock();
raw_spin_lock(&this_rq->lock);
if (pulled_task || time_after(jiffies, this_rq->next_balance)) {
/*
* We are going idle. next_balance may be set based on
* a busy processor. So reset next_balance.
*/
this_rq->next_balance = next_balance;
}
}
/*
* active_load_balance_cpu_stop is run by cpu stopper. It pushes
* running tasks off the busiest CPU onto idle CPUs. It requires at
* least 1 task to be running on each physical CPU where possible, and
* avoids physical / logical imbalances.
*/
static int active_load_balance_cpu_stop(void *data)
{
struct rq *busiest_rq = data;
int busiest_cpu = cpu_of(busiest_rq);
int target_cpu = busiest_rq->push_cpu;
struct rq *target_rq = cpu_rq(target_cpu);
struct sched_domain *sd;
raw_spin_lock_irq(&busiest_rq->lock);
/* make sure the requested cpu hasn't gone down in the meantime */
if (unlikely(busiest_cpu != smp_processor_id() ||
!busiest_rq->active_balance))
goto out_unlock;
/* Is there any task to move? */
if (busiest_rq->nr_running <= 1)
goto out_unlock;
/*
* This condition is "impossible", if it occurs
* we need to fix it. Originally reported by
* Bjorn Helgaas on a 128-cpu setup.
*/
BUG_ON(busiest_rq == target_rq);
/* move a task from busiest_rq to target_rq */
double_lock_balance(busiest_rq, target_rq);
/* Search for an sd spanning us and the target CPU. */
rcu_read_lock();
for_each_domain(target_cpu, sd) {
if ((sd->flags & SD_LOAD_BALANCE) &&
cpumask_test_cpu(busiest_cpu, sched_domain_span(sd)))
break;
}
if (likely(sd)) {
struct lb_env env = {
.sd = sd,
.dst_cpu = target_cpu,
.dst_rq = target_rq,
.src_cpu = busiest_rq->cpu,
.src_rq = busiest_rq,
.idle = CPU_IDLE,
};
schedstat_inc(sd, alb_count);
if (move_one_task(&env))
schedstat_inc(sd, alb_pushed);
else
schedstat_inc(sd, alb_failed);
}
rcu_read_unlock();
double_unlock_balance(busiest_rq, target_rq);
out_unlock:
busiest_rq->active_balance = 0;
raw_spin_unlock_irq(&busiest_rq->lock);
return 0;
}
#ifdef CONFIG_NO_HZ_COMMON
/*
* idle load balancing details
* - When one of the busy CPUs notice that there may be an idle rebalancing
* needed, they will kick the idle load balancer, which then does idle
* load balancing for all the idle CPUs.
*/
static struct {
cpumask_var_t idle_cpus_mask;
atomic_t nr_cpus;
unsigned long next_balance; /* in jiffy units */
} nohz ____cacheline_aligned;
static inline int find_new_ilb(int call_cpu)
{
#ifdef CONFIG_HMP_PACK_SMALL_TASK
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
struct sched_domain *sd;
int ilb_new = nr_cpu_ids;
int ilb_return = 0;
int ilb = cpumask_first(nohz.idle_cpus_mask);
if(PA_ENABLE)
{
int buddy = per_cpu(sd_pack_buddy, call_cpu);
/*
* If we have a pack buddy CPU, we try to run load balance on a CPU
* that is close to the buddy.
*/
if (buddy != -1)
for_each_domain(buddy, sd) {
if (sd->flags & SD_SHARE_CPUPOWER)
continue;
ilb_new = cpumask_first_and(sched_domain_span(sd),
nohz.idle_cpus_mask);
if (ilb_new < nr_cpu_ids)
break;
}
}
if (ilb < nr_cpu_ids && idle_cpu(ilb)) {
ilb_return = 1;
}
if (ilb_new < nr_cpu_ids) {
if (idle_cpu(ilb_new)) {
if(PA_ENABLE && ilb_return && ilb_new != ilb) {
AVOID_WAKE_UP_FROM_CPUX_TO_CPUY_COUNT[call_cpu][ilb]++;
#ifdef CONFIG_HMP_TRACER
trace_sched_power_aware_active(POWER_AWARE_ACTIVE_MODULE_AVOID_WAKE_UP_FORM_CPUX_TO_CPUY, 0, call_cpu, ilb);
#endif /* CONFIG_HMP_TRACER */
}
return ilb_new;
}
}
if(ilb_return) {
return ilb;
}
return nr_cpu_ids;
#else /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
struct sched_domain *sd;
int ilb = cpumask_first(nohz.idle_cpus_mask);
int buddy = per_cpu(sd_pack_buddy, call_cpu);
/*
* If we have a pack buddy CPU, we try to run load balance on a CPU
* that is close to the buddy.
*/
if (buddy != -1)
for_each_domain(buddy, sd) {
if (sd->flags & SD_SHARE_CPUPOWER)
continue;
ilb = cpumask_first_and(sched_domain_span(sd),
nohz.idle_cpus_mask);
if (ilb < nr_cpu_ids)
break;
}
if (ilb < nr_cpu_ids && idle_cpu(ilb))
return ilb;
return nr_cpu_ids;
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
#else /* CONFIG_HMP_PACK_SMALL_TASK */
int ilb = cpumask_first(nohz.idle_cpus_mask);
#ifdef CONFIG_MTK_SCHED_CMP_TGS
/* Find nohz balancing to occur in the same cluster firstly */
int new_ilb;
struct cpumask tmp;
//Find idle cpu with online one
get_cluster_cpus(&tmp, get_cluster_id(call_cpu), true);
new_ilb = cpumask_first_and(nohz.idle_cpus_mask, &tmp);
if (new_ilb < nr_cpu_ids && idle_cpu(new_ilb))
{
#ifdef CONFIG_MTK_SCHED_CMP_POWER_AWARE_CONTROLLER
if(new_ilb != ilb)
{
mt_sched_printf("[PA]find_new_ilb(cpu%x), new_ilb = %d, ilb = %d\n", call_cpu, new_ilb, ilb);
AVOID_WAKE_UP_FROM_CPUX_TO_CPUY_COUNT[call_cpu][ilb]++;
}
#endif
return new_ilb;
}
#endif /* CONFIG_MTK_SCHED_CMP_TGS */
if (ilb < nr_cpu_ids && idle_cpu(ilb))
return ilb;
return nr_cpu_ids;
#endif /* CONFIG_HMP_PACK_SMALL_TASK */
}
/*
* Kick a CPU to do the nohz balancing, if it is time for it. We pick the
* nohz_load_balancer CPU (if there is one) otherwise fallback to any idle
* CPU (if there is one).
*/
static void nohz_balancer_kick(int cpu)
{
int ilb_cpu;
nohz.next_balance++;
ilb_cpu = find_new_ilb(cpu);
if (ilb_cpu >= nr_cpu_ids)
return;
if (test_and_set_bit(NOHZ_BALANCE_KICK, nohz_flags(ilb_cpu)))
return;
/*
* Use smp_send_reschedule() instead of resched_cpu().
* This way we generate a sched IPI on the target cpu which
* is idle. And the softirq performing nohz idle load balance
* will be run before returning from the IPI.
*/
smp_send_reschedule(ilb_cpu);
return;
}
static inline void nohz_balance_exit_idle(int cpu)
{
if (unlikely(test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))) {
cpumask_clear_cpu(cpu, nohz.idle_cpus_mask);
atomic_dec(&nohz.nr_cpus);
clear_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
}
}
static inline void set_cpu_sd_state_busy(void)
{
struct sched_domain *sd;
int cpu = smp_processor_id();
rcu_read_lock();
sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd);
if (!sd || !sd->nohz_idle)
goto unlock;
sd->nohz_idle = 0;
for (; sd; sd = sd->parent)
atomic_inc(&sd->groups->sgp->nr_busy_cpus);
unlock:
rcu_read_unlock();
}
void set_cpu_sd_state_idle(void)
{
struct sched_domain *sd;
int cpu = smp_processor_id();
rcu_read_lock();
sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd);
if (!sd || sd->nohz_idle)
goto unlock;
sd->nohz_idle = 1;
for (; sd; sd = sd->parent)
atomic_dec(&sd->groups->sgp->nr_busy_cpus);
unlock:
rcu_read_unlock();
}
/*
* This routine will record that the cpu is going idle with tick stopped.
* This info will be used in performing idle load balancing in the future.
*/
void nohz_balance_enter_idle(int cpu)
{
/*
* If this cpu is going down, then nothing needs to be done.
*/
if (!cpu_active(cpu))
return;
if (test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))
return;
cpumask_set_cpu(cpu, nohz.idle_cpus_mask);
atomic_inc(&nohz.nr_cpus);
set_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
}
static int __cpuinit sched_ilb_notifier(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_DYING:
nohz_balance_exit_idle(smp_processor_id());
return NOTIFY_OK;
default:
return NOTIFY_DONE;
}
}
#endif
static DEFINE_SPINLOCK(balancing);
/*
* Scale the max load_balance interval with the number of CPUs in the system.
* This trades load-balance latency on larger machines for less cross talk.
*/
void update_max_interval(void)
{
max_load_balance_interval = HZ*num_online_cpus()/10;
}
/*
* It checks each scheduling domain to see if it is due to be balanced,
* and initiates a balancing operation if so.
*
* Balancing parameters are set up in init_sched_domains.
*/
static void rebalance_domains(int cpu, enum cpu_idle_type idle)
{
int balance = 1;
struct rq *rq = cpu_rq(cpu);
unsigned long interval;
struct sched_domain *sd;
/* Earliest time when we have to do rebalance again */
unsigned long next_balance = jiffies + 60*HZ;
int update_next_balance = 0;
int need_serialize;
update_blocked_averages(cpu);
rcu_read_lock();
for_each_domain(cpu, sd) {
if (!(sd->flags & SD_LOAD_BALANCE))
continue;
interval = sd->balance_interval;
if (idle != CPU_IDLE)
interval *= sd->busy_factor;
/* scale ms to jiffies */
interval = msecs_to_jiffies(interval);
interval = clamp(interval, 1UL, max_load_balance_interval);
need_serialize = sd->flags & SD_SERIALIZE;
if (need_serialize) {
if (!spin_trylock(&balancing))
goto out;
}
if (time_after_eq(jiffies, sd->last_balance + interval)) {
if (load_balance(cpu, rq, sd, idle, &balance)) {
/*
* The LBF_SOME_PINNED logic could have changed
* env->dst_cpu, so we can't know our idle
* state even if we migrated tasks. Update it.
*/
idle = idle_cpu(cpu) ? CPU_IDLE : CPU_NOT_IDLE;
}
sd->last_balance = jiffies;
}
if (need_serialize)
spin_unlock(&balancing);
out:
if (time_after(next_balance, sd->last_balance + interval)) {
next_balance = sd->last_balance + interval;
update_next_balance = 1;
}
/*
* Stop the load balance at this level. There is another
* CPU in our sched group which is doing load balancing more
* actively.
*/
if (!balance)
break;
}
rcu_read_unlock();
/*
* next_balance will be updated only when there is a need.
* When the cpu is attached to null domain for ex, it will not be
* updated.
*/
if (likely(update_next_balance))
rq->next_balance = next_balance;
}
#ifdef CONFIG_NO_HZ_COMMON
/*
* In CONFIG_NO_HZ_COMMON case, the idle balance kickee will do the
* rebalancing for all the cpus for whom scheduler ticks are stopped.
*/
static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle)
{
struct rq *this_rq = cpu_rq(this_cpu);
struct rq *rq;
int balance_cpu;
if (idle != CPU_IDLE ||
!test_bit(NOHZ_BALANCE_KICK, nohz_flags(this_cpu)))
goto end;
for_each_cpu(balance_cpu, nohz.idle_cpus_mask) {
if (balance_cpu == this_cpu || !idle_cpu(balance_cpu))
continue;
/*
* If this cpu gets work to do, stop the load balancing
* work being done for other cpus. Next load
* balancing owner will pick it up.
*/
if (need_resched())
break;
rq = cpu_rq(balance_cpu);
raw_spin_lock_irq(&rq->lock);
update_rq_clock(rq);
update_idle_cpu_load(rq);
raw_spin_unlock_irq(&rq->lock);
rebalance_domains(balance_cpu, CPU_IDLE);
if (time_after(this_rq->next_balance, rq->next_balance))
this_rq->next_balance = rq->next_balance;
}
nohz.next_balance = this_rq->next_balance;
end:
clear_bit(NOHZ_BALANCE_KICK, nohz_flags(this_cpu));
}
/*
* Current heuristic for kicking the idle load balancer in the presence
* of an idle cpu is the system.
* - This rq has more than one task.
* - At any scheduler domain level, this cpu's scheduler group has multiple
* busy cpu's exceeding the group's power.
* - For SD_ASYM_PACKING, if the lower numbered cpu's in the scheduler
* domain span are idle.
*/
static inline int nohz_kick_needed(struct rq *rq, int cpu)
{
unsigned long now = jiffies;
struct sched_domain *sd;
if (unlikely(idle_cpu(cpu)))
return 0;
/*
* We may be recently in ticked or tickless idle mode. At the first
* busy tick after returning from idle, we will update the busy stats.
*/
set_cpu_sd_state_busy();
nohz_balance_exit_idle(cpu);
/*
* None are in tickless mode and hence no need for NOHZ idle load
* balancing.
*/
if (likely(!atomic_read(&nohz.nr_cpus)))
return 0;
if (time_before(now, nohz.next_balance))
return 0;
#ifdef CONFIG_SCHED_HMP
/*
* Bail out if there are no nohz CPUs in our
* HMP domain, since we will move tasks between
* domains through wakeup and force balancing
* as necessary based upon task load.
*/
if (cpumask_first_and(nohz.idle_cpus_mask,
&((struct hmp_domain *)hmp_cpu_domain(cpu))->cpus) >= nr_cpu_ids)
return 0;
#endif
if (rq->nr_running >= 2)
goto need_kick;
rcu_read_lock();
for_each_domain(cpu, sd) {
struct sched_group *sg = sd->groups;
struct sched_group_power *sgp = sg->sgp;
int nr_busy = atomic_read(&sgp->nr_busy_cpus);
if (sd->flags & SD_SHARE_PKG_RESOURCES && nr_busy > 1)
goto need_kick_unlock;
if (sd->flags & SD_ASYM_PACKING && nr_busy != sg->group_weight
&& (cpumask_first_and(nohz.idle_cpus_mask,
sched_domain_span(sd)) < cpu))
goto need_kick_unlock;
if (!(sd->flags & (SD_SHARE_PKG_RESOURCES | SD_ASYM_PACKING)))
break;
}
rcu_read_unlock();
return 0;
need_kick_unlock:
rcu_read_unlock();
need_kick:
return 1;
}
#else
static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle) { }
#endif
#ifdef CONFIG_SCHED_HMP
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
/*
* Heterogenous Multi-Processor (HMP) - Declaration and Useful Macro
*/
/* Function Declaration */
static int hmp_up_stable(int cpu);
static int hmp_down_stable(int cpu);
static unsigned int hmp_up_migration(int cpu, int *target_cpu, struct sched_entity *se,
struct clb_env *clbenv);
static unsigned int hmp_down_migration(int cpu, int *target_cpu, struct sched_entity *se,
struct clb_env *clbenv);
#define hmp_caller_is_gb(caller) ((HMP_GB == caller)?1:0)
#define hmp_cpu_is_fast(cpu) cpumask_test_cpu(cpu,&hmp_fast_cpu_mask)
#define hmp_cpu_is_slow(cpu) cpumask_test_cpu(cpu,&hmp_slow_cpu_mask)
#define hmp_cpu_stable(cpu) (hmp_cpu_is_fast(cpu)? \
hmp_up_stable(cpu):hmp_down_stable(cpu))
#define hmp_inc(v) ((v) + 1)
#define hmp_dec(v) ((v) - 1)
#define hmp_pos(v) ((v) < (0) ? (0) : (v))
#define task_created(f) ((SD_BALANCE_EXEC == f || SD_BALANCE_FORK == f)?1:0)
#define task_cpus_allowed(mask,p) cpumask_intersects(mask,tsk_cpus_allowed(p))
#define task_slow_cpu_allowed(p) task_cpus_allowed(&hmp_slow_cpu_mask,p)
#define task_fast_cpu_allowed(p) task_cpus_allowed(&hmp_fast_cpu_mask,p)
/*
* Heterogenous Multi-Processor (HMP) - Utility Function
*/
/*
* These functions add next up/down migration delay that prevents the task from
* doing another migration in the same direction until the delay has expired.
*/
static int hmp_up_stable(int cpu)
{
struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
u64 now = cfs_rq_clock_task(cfs_rq);
if (((now - hmp_last_up_migration(cpu)) >> 10) < hmp_next_up_threshold)
return 0;
return 1;
}
static int hmp_down_stable(int cpu)
{
struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
u64 now = cfs_rq_clock_task(cfs_rq);
if (((now - hmp_last_down_migration(cpu)) >> 10) < hmp_next_down_threshold)
return 0;
return 1;
}
/* Select the most appropriate CPU from hmp cluster */
static unsigned int hmp_select_cpu(unsigned int caller, struct task_struct *p,
struct cpumask *mask, int prev)
{
int curr = 0;
int target = NR_CPUS;
unsigned long curr_wload = 0;
unsigned long target_wload = 0;
struct cpumask srcp;
cpumask_and(&srcp, cpu_online_mask, mask);
target = cpumask_any_and(&srcp, tsk_cpus_allowed(p));
if (NR_CPUS == target)
goto out;
/*
* RT class is taken into account because CPU load is multiplied
* by the total number of CPU runnable tasks that includes RT tasks.
*/
target_wload = hmp_inc(cfs_load(target));
target_wload += cfs_pending_load(target);
target_wload *= rq_length(target);
for_each_cpu(curr, mask) {
/* Check CPU status and task affinity */
if(!cpu_online(curr) || !cpumask_test_cpu(curr, tsk_cpus_allowed(p)))
continue;
/* For global load balancing, unstable CPU will be bypassed */
if(hmp_caller_is_gb(caller) && !hmp_cpu_stable(curr))
continue;
curr_wload = hmp_inc(cfs_load(curr));
curr_wload += cfs_pending_load(curr);
curr_wload *= rq_length(curr);
if(curr_wload < target_wload) {
target_wload = curr_wload;
target = curr;
} else if(curr_wload == target_wload && curr == prev) {
target = curr;
}
}
out:
return target;
}
/*
* Heterogenous Multi-Processor (HMP) - Task Runqueue Selection
*/
/* This function enhances the original task selection function */
static int hmp_select_task_rq_fair(int sd_flag, struct task_struct *p,
int prev_cpu, int new_cpu)
{
#ifdef CONFIG_HMP_TASK_ASSIGNMENT
int step = 0;
struct sched_entity *se = &p->se;
int B_target = NR_CPUS;
int L_target = NR_CPUS;
struct clb_env clbenv;
#ifdef CONFIG_HMP_TRACER
int cpu = 0;
for_each_online_cpu(cpu)
trace_sched_cfs_runnable_load(cpu,cfs_load(cpu),cfs_length(cpu));
#endif
// error handling
if (prev_cpu >= NR_CPUS)
return new_cpu;
/*
* Skip all the checks if only one CPU is online.
* Otherwise, select the most appropriate CPU from cluster.
*/
if (num_online_cpus() == 1)
goto out;
B_target = hmp_select_cpu(HMP_SELECT_RQ,p,&hmp_fast_cpu_mask,prev_cpu);
L_target = hmp_select_cpu(HMP_SELECT_RQ,p,&hmp_slow_cpu_mask,prev_cpu);
/*
* Only one cluster exists or only one cluster is allowed for this task
* Case 1: return the runqueue whose load is minimum
* Case 2: return original CFS runqueue selection result
*/
#ifdef CONFIG_HMP_DISCARD_CFS_SELECTION_RESULT
if(NR_CPUS == B_target && NR_CPUS == L_target)
goto out;
if(NR_CPUS == B_target)
goto select_slow;
if(NR_CPUS == L_target)
goto select_fast;
#else
if(NR_CPUS == B_target || NR_CPUS == L_target)
goto out;
#endif
/*
* Two clusters exist and both clusters are allowed for this task
* Step 1: Move newly created task to the cpu where no tasks are running
* Step 2: Migrate heavy-load task to big
* Step 3: Migrate light-load task to LITTLE
* Step 4: Make sure the task stays in its previous hmp domain
*/
step = 1;
if (task_created(sd_flag) && !task_low_priority(p->prio)) {
if (!rq_length(B_target))
goto select_fast;
if (!rq_length(L_target))
goto select_slow;
}
memset(&clbenv, 0, sizeof(clbenv));
clbenv.flags |= HMP_SELECT_RQ;
clbenv.lcpus = &hmp_slow_cpu_mask;
clbenv.bcpus = &hmp_fast_cpu_mask;
clbenv.ltarget = L_target;
clbenv.btarget = B_target;
sched_update_clbstats(&clbenv);
step = 2;
if (hmp_up_migration(L_target, &B_target, se, &clbenv))
goto select_fast;
step = 3;
if (hmp_down_migration(B_target, &L_target, se, &clbenv))
goto select_slow;
step = 4;
if (hmp_cpu_is_slow(prev_cpu))
goto select_slow;
goto select_fast;
select_fast:
new_cpu = B_target;
goto out;
select_slow:
new_cpu = L_target;
goto out;
out:
// it happens when num_online_cpus=1
if (new_cpu >= nr_cpu_ids)
{
//BUG_ON(1);
new_cpu = prev_cpu;
}
cfs_nr_pending(new_cpu)++;
cfs_pending_load(new_cpu) += se_load(se);
#ifdef CONFIG_HMP_TRACER
trace_sched_hmp_load(clbenv.bstats.load_avg, clbenv.lstats.load_avg);
trace_sched_hmp_select_task_rq(p,step,sd_flag,prev_cpu,new_cpu,
se_load(se),&clbenv.bstats,&clbenv.lstats);
#endif
#ifdef CONFIG_MET_SCHED_HMP
HmpLoad(clbenv.bstats.load_avg, clbenv.lstats.load_avg);
#endif
#endif /* CONFIG_HMP_TASK_ASSIGNMENT */
return new_cpu;
}
/*
* Heterogenous Multi-Processor (HMP) - Task Dynamic Migration Threshold
*/
/*
* If the workload between clusters is not balanced, adjust migration
* threshold in an attempt to move task to the cluster where the workload
* is not heavy
*/
/*
* According to ARM's cpu_efficiency table, the computing power of CA15 and
* CA7 are 3891 and 2048 respectively. Thus, we assume big has twice the
* computing power of LITTLE
*/
#define HMP_RATIO(v) ((v)*17/10)
#define hmp_fast_cpu_has_spare_cycles(B,cpu_load) (cpu_load < \
(HMP_RATIO(B->cpu_capacity) - (B->cpu_capacity >> 2)))
#define hmp_task_fast_cpu_afford(B,se,cpu) (B->acap > 0 \
&& hmp_fast_cpu_has_spare_cycles(B,se_load(se) + cfs_load(cpu)))
#define hmp_fast_cpu_oversubscribed(caller,B,se,cpu) \
(hmp_caller_is_gb(caller)? \
!hmp_fast_cpu_has_spare_cycles(B,cfs_load(cpu)): \
!hmp_task_fast_cpu_afford(B,se,cpu))
#define hmp_task_slow_cpu_afford(L,se) \
(L->acap > 0 && L->acap >= se_load(se))
/* Macro used by low-priorty task filter */
#define hmp_low_prio_task_up_rejected(p,B,L) \
(task_low_priority(p->prio) && \
(B->ntask >= B->ncpu || 0 != L->nr_normal_prio_task) && \
(p->se.avg.load_avg_ratio < 800))
#define hmp_low_prio_task_down_allowed(p,B,L) \
(task_low_priority(p->prio) && !B->nr_dequeuing_low_prio && \
B->ntask >= B->ncpu && 0 != L->nr_normal_prio_task && \
(p->se.avg.load_avg_ratio < 800))
/* Migration check result */
#define HMP_BIG_NOT_OVERSUBSCRIBED (0x01)
#define HMP_BIG_CAPACITY_INSUFFICIENT (0x02)
#define HMP_LITTLE_CAPACITY_INSUFFICIENT (0x04)
#define HMP_LOW_PRIORITY_FILTER (0x08)
#define HMP_BIG_BUSY_LITTLE_IDLE (0x10)
#define HMP_BIG_IDLE (0x20)
#define HMP_MIGRATION_APPROVED (0x100)
#define HMP_TASK_UP_MIGRATION (0x200)
#define HMP_TASK_DOWN_MIGRATION (0x400)
/* Migration statistics */
#ifdef CONFIG_HMP_TRACER
struct hmp_statisic hmp_stats;
#endif
static inline void hmp_dynamic_threshold(struct clb_env *clbenv)
{
struct clb_stats *L = &clbenv->lstats;
struct clb_stats *B = &clbenv->bstats;
unsigned int hmp_threshold_diff = hmp_up_threshold - hmp_down_threshold;
unsigned int B_normalized_acap = hmp_pos(HMP_RATIO(B->scaled_acap));
unsigned int B_normalized_atask = hmp_pos(HMP_RATIO(B->scaled_atask));
unsigned int L_normalized_acap = hmp_pos(L->scaled_acap);
unsigned int L_normalized_atask = hmp_pos(L->scaled_atask);
#ifdef CONFIG_HMP_DYNAMIC_THRESHOLD
L->threshold = hmp_threshold_diff;
L->threshold *= hmp_inc(L_normalized_acap) * hmp_inc(L_normalized_atask);
L->threshold /= hmp_inc(B_normalized_acap + L_normalized_acap);
L->threshold /= hmp_inc(B_normalized_atask + L_normalized_atask);
L->threshold = hmp_down_threshold + L->threshold;
B->threshold = hmp_threshold_diff;
B->threshold *= hmp_inc(B_normalized_acap) * hmp_inc(B_normalized_atask);
B->threshold /= hmp_inc(B_normalized_acap + L_normalized_acap);
B->threshold /= hmp_inc(B_normalized_atask + L_normalized_atask);
B->threshold = hmp_up_threshold - B->threshold;
#else /* !CONFIG_HMP_DYNAMIC_THRESHOLD */
clbenv->lstats.threshold = hmp_down_threshold; // down threshold
clbenv->bstats.threshold = hmp_up_threshold; // up threshold
#endif /* CONFIG_HMP_DYNAMIC_THRESHOLD */
mt_sched_printf("[%s]\tup/dl:%4d/%4d bcpu(%d):%d/%d, lcpu(%d):%d/%d\n", __func__,
B->threshold, L->threshold,
clbenv->btarget, clbenv->bstats.cpu_capacity, clbenv->bstats.cpu_power,
clbenv->ltarget, clbenv->lstats.cpu_capacity, clbenv->lstats.cpu_power);
}
/*
* Check whether this task should be migrated to big
* Briefly summarize the flow as below;
* 1) Migration stabilizing
* 1.5) Keep all cpu busy
* 2) Filter low-priorty task
* 3) Check CPU capacity
* 4) Check dynamic migration threshold
*/
static unsigned int hmp_up_migration(int cpu, int *target_cpu, struct sched_entity *se,
struct clb_env *clbenv)
{
struct task_struct *p = task_of(se);
struct clb_stats *L, *B;
struct mcheck *check;
int curr_cpu = cpu;
unsigned int caller = clbenv->flags;
L = &clbenv->lstats;
B = &clbenv->bstats;
check = &clbenv->mcheck;
check->status = clbenv->flags;
check->status |= HMP_TASK_UP_MIGRATION;
check->result = 0;
/*
* No migration is needed if
* 1) There is only one cluster
* 2) Task is already in big cluster
* 3) It violates task affinity
*/
if (!L->ncpu || !B->ncpu
|| cpumask_test_cpu(curr_cpu, clbenv->bcpus)
|| !cpumask_intersects(clbenv->bcpus, tsk_cpus_allowed(p)))
goto out;
/*
* [1] Migration stabilizing
* Let the task load settle before doing another up migration.
* It can prevent a bunch of tasks from migrating to a unstable CPU.
*/
if (!hmp_up_stable(*target_cpu))
goto out;
/* [2] Filter low-priorty task */
#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
if (hmp_low_prio_task_up_rejected(p,B,L)) {
check->status |= HMP_LOW_PRIORITY_FILTER;
goto trace;
}
#endif
// [2.5]if big is idle, just go to big
if (rq_length(*target_cpu)==0)
{
check->status |= HMP_BIG_IDLE;
check->status |= HMP_MIGRATION_APPROVED;
check->result = 1;
goto trace;
}
/*
* [3] Check CPU capacity
* Forbid up-migration if big CPU can't handle this task
*/
if (!hmp_task_fast_cpu_afford(B,se,*target_cpu)) {
check->status |= HMP_BIG_CAPACITY_INSUFFICIENT;
goto trace;
}
/*
* [4] Check dynamic migration threshold
* Migrate task from LITTLE to big if load is greater than up-threshold
*/
if (se_load(se) > B->threshold) {
check->status |= HMP_MIGRATION_APPROVED;
check->result = 1;
}
trace:
#ifdef CONFIG_HMP_TRACER
if(check->result && hmp_caller_is_gb(caller))
hmp_stats.nr_force_up++;
trace_sched_hmp_stats(&hmp_stats);
trace_sched_dynamic_threshold(task_of(se),B->threshold,check->status,
curr_cpu,*target_cpu,se_load(se),B,L);
#endif
#ifdef CONFIG_MET_SCHED_HMP
TaskTh(B->threshold,L->threshold);
HmpStat(&hmp_stats);
#endif
out:
return check->result;
}
/*
* Check whether this task should be migrated to LITTLE
* Briefly summarize the flow as below;
* 1) Migration stabilizing
* 1.5) Keep all cpu busy
* 2) Filter low-priorty task
* 3) Check CPU capacity
* 4) Check dynamic migration threshold
*/
static unsigned int hmp_down_migration(int cpu, int *target_cpu, struct sched_entity *se,
struct clb_env *clbenv)
{
struct task_struct *p = task_of(se);
struct clb_stats *L, *B;
struct mcheck *check;
int curr_cpu = cpu;
unsigned int caller = clbenv->flags;
L = &clbenv->lstats;
B = &clbenv->bstats;
check = &clbenv->mcheck;
check->status = caller;
check->status |= HMP_TASK_DOWN_MIGRATION;
check->result = 0;
/*
* No migration is needed if
* 1) There is only one cluster
* 2) Task is already in LITTLE cluster
* 3) It violates task affinity
*/
if (!L->ncpu || !B->ncpu
|| cpumask_test_cpu(curr_cpu, clbenv->lcpus)
|| !cpumask_intersects(clbenv->lcpus, tsk_cpus_allowed(p)))
goto out;
/*
* [1] Migration stabilizing
* Let the task load settle before doing another down migration.
* It can prevent a bunch of tasks from migrating to a unstable CPU.
*/
if (!hmp_down_stable(*target_cpu))
goto out;
// [1.5]if big is busy and little is idle, just go to little
if (rq_length(*target_cpu)==0 && caller == HMP_SELECT_RQ && rq_length(curr_cpu)>0)
{
check->status |= HMP_BIG_BUSY_LITTLE_IDLE;
check->status |= HMP_MIGRATION_APPROVED;
check->result = 1;
goto trace;
}
/* [2] Filter low-priorty task */
#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
if (hmp_low_prio_task_down_allowed(p,B,L)) {
cfs_nr_dequeuing_low_prio(curr_cpu)++;
check->status |= HMP_LOW_PRIORITY_FILTER;
check->status |= HMP_MIGRATION_APPROVED;
check->result = 1;
goto trace;
}
#endif
/*
* [3] Check CPU capacity
* Forbid down-migration if either of the following conditions is true
* 1) big cpu is not oversubscribed (if big CPU seems to have spare
* cycles, do not force this task to run on LITTLE CPU, but
* keep it staying in its previous cluster instead)
* 2) LITTLE cpu doesn't have available capacity for this new task
*/
if (!hmp_fast_cpu_oversubscribed(caller,B,se,curr_cpu)) {
check->status |= HMP_BIG_NOT_OVERSUBSCRIBED;
goto trace;
}
if (!hmp_task_slow_cpu_afford(L,se)) {
check->status |= HMP_LITTLE_CAPACITY_INSUFFICIENT;
goto trace;
}
/*
* [4] Check dynamic migration threshold
* Migrate task from big to LITTLE if load ratio is less than
* or equal to down-threshold
*/
if (L->threshold >= se_load(se)) {
check->status |= HMP_MIGRATION_APPROVED;
check->result = 1;
}
trace:
#ifdef CONFIG_HMP_TRACER
if (check->result && hmp_caller_is_gb(caller))
hmp_stats.nr_force_down++;
trace_sched_hmp_stats(&hmp_stats);
trace_sched_dynamic_threshold(task_of(se),L->threshold,check->status,
curr_cpu,*target_cpu,se_load(se),B,L);
#endif
#ifdef CONFIG_MET_SCHED_HMP
TaskTh(B->threshold,L->threshold);
HmpStat(&hmp_stats);
#endif
out:
return check->result;
}
#else /* CONFIG_SCHED_HMP_ENHANCEMENT */
/* Check if task should migrate to a faster cpu */
static unsigned int hmp_up_migration(int cpu, int *target_cpu, struct sched_entity *se)
{
struct task_struct *p = task_of(se);
struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
u64 now;
if (target_cpu)
*target_cpu = NR_CPUS;
if (hmp_cpu_is_fastest(cpu))
return 0;
#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
/* Filter by task priority */
if (p->prio >= hmp_up_prio)
return 0;
#endif
if (se->avg.load_avg_ratio < hmp_up_threshold)
return 0;
/* Let the task load settle before doing another up migration */
now = cfs_rq_clock_task(cfs_rq);
if (((now - se->avg.hmp_last_up_migration) >> 10)
< hmp_next_up_threshold)
return 0;
/* Target domain load < 94% */
if (hmp_domain_min_load(hmp_faster_domain(cpu), target_cpu)
> NICE_0_LOAD-64)
return 0;
if (cpumask_intersects(&hmp_faster_domain(cpu)->cpus,
tsk_cpus_allowed(p)))
return 1;
return 0;
}
/* Check if task should migrate to a slower cpu */
static unsigned int hmp_down_migration(int cpu, struct sched_entity *se)
{
struct task_struct *p = task_of(se);
struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
u64 now;
if (hmp_cpu_is_slowest(cpu))
return 0;
#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
/* Filter by task priority */
if ((p->prio >= hmp_up_prio) &&
cpumask_intersects(&hmp_slower_domain(cpu)->cpus,
tsk_cpus_allowed(p))) {
return 1;
}
#endif
/* Let the task load settle before doing another down migration */
now = cfs_rq_clock_task(cfs_rq);
if (((now - se->avg.hmp_last_down_migration) >> 10)
< hmp_next_down_threshold)
return 0;
if (cpumask_intersects(&hmp_slower_domain(cpu)->cpus,
tsk_cpus_allowed(p))
&& se->avg.load_avg_ratio < hmp_down_threshold) {
return 1;
}
return 0;
}
#endif /* CONFIG_SCHED_HMP_ENHANCEMENT */
/*
* hmp_can_migrate_task - may task p from runqueue rq be migrated to this_cpu?
* Ideally this function should be merged with can_migrate_task() to avoid
* redundant code.
*/
static int hmp_can_migrate_task(struct task_struct *p, struct lb_env *env)
{
int tsk_cache_hot = 0;
/*
* We do not migrate tasks that are:
* 1) running (obviously), or
* 2) cannot be migrated to this CPU due to cpus_allowed
*/
if (!cpumask_test_cpu(env->dst_cpu, tsk_cpus_allowed(p))) {
schedstat_inc(p, se.statistics.nr_failed_migrations_affine);
return 0;
}
env->flags &= ~LBF_ALL_PINNED;
if (task_running(env->src_rq, p)) {
schedstat_inc(p, se.statistics.nr_failed_migrations_running);
return 0;
}
/*
* Aggressive migration if:
* 1) task is cache cold, or
* 2) too many balance attempts have failed.
*/
#if defined(CONFIG_MT_LOAD_BALANCE_ENHANCEMENT)
tsk_cache_hot = task_hot(p, env->src_rq->clock_task, env->sd, env->mt_check_cache_in_idle);
#else
tsk_cache_hot = task_hot(p, env->src_rq->clock_task, env->sd);
#endif
if (!tsk_cache_hot ||
env->sd->nr_balance_failed > env->sd->cache_nice_tries) {
#ifdef CONFIG_SCHEDSTATS
if (tsk_cache_hot) {
schedstat_inc(env->sd, lb_hot_gained[env->idle]);
schedstat_inc(p, se.statistics.nr_forced_migrations);
}
#endif
return 1;
}
return 1;
}
/*
* move_specific_task tries to move a specific task.
* Returns 1 if successful and 0 otherwise.
* Called with both runqueues locked.
*/
static int move_specific_task(struct lb_env *env, struct task_struct *pm)
{
struct task_struct *p, *n;
list_for_each_entry_safe(p, n, &env->src_rq->cfs_tasks, se.group_node) {
if (throttled_lb_pair(task_group(p), env->src_rq->cpu,
env->dst_cpu))
continue;
if (!hmp_can_migrate_task(p, env))
continue;
/* Check if we found the right task */
if (p != pm)
continue;
move_task(p, env);
/*
* Right now, this is only the third place move_task()
* is called, so we can safely collect move_task()
* stats here rather than inside move_task().
*/
schedstat_inc(env->sd, lb_gained[env->idle]);
return 1;
}
return 0;
}
/*
* hmp_active_task_migration_cpu_stop is run by cpu stopper and used to
* migrate a specific task from one runqueue to another.
* hmp_force_up_migration uses this to push a currently running task
* off a runqueue.
* Based on active_load_balance_stop_cpu and can potentially be merged.
*/
static int hmp_active_task_migration_cpu_stop(void *data)
{
struct rq *busiest_rq = data;
struct task_struct *p = busiest_rq->migrate_task;
int busiest_cpu = cpu_of(busiest_rq);
int target_cpu = busiest_rq->push_cpu;
struct rq *target_rq = cpu_rq(target_cpu);
struct sched_domain *sd;
raw_spin_lock_irq(&busiest_rq->lock);
/* make sure the requested cpu hasn't gone down in the meantime */
if (unlikely(busiest_cpu != smp_processor_id() ||
!busiest_rq->active_balance)) {
goto out_unlock;
}
/* Is there any task to move? */
if (busiest_rq->nr_running <= 1)
goto out_unlock;
/* Task has migrated meanwhile, abort forced migration */
if (task_rq(p) != busiest_rq)
goto out_unlock;
/*
* This condition is "impossible", if it occurs
* we need to fix it. Originally reported by
* Bjorn Helgaas on a 128-cpu setup.
*/
BUG_ON(busiest_rq == target_rq);
/* move a task from busiest_rq to target_rq */
double_lock_balance(busiest_rq, target_rq);
/* Search for an sd spanning us and the target CPU. */
rcu_read_lock();
for_each_domain(target_cpu, sd) {
if (cpumask_test_cpu(busiest_cpu, sched_domain_span(sd)))
break;
}
if (likely(sd)) {
struct lb_env env = {
.sd = sd,
.dst_cpu = target_cpu,
.dst_rq = target_rq,
.src_cpu = busiest_rq->cpu,
.src_rq = busiest_rq,
.idle = CPU_IDLE,
};
schedstat_inc(sd, alb_count);
if (move_specific_task(&env, p))
schedstat_inc(sd, alb_pushed);
else
schedstat_inc(sd, alb_failed);
}
rcu_read_unlock();
double_unlock_balance(busiest_rq, target_rq);
out_unlock:
busiest_rq->active_balance = 0;
raw_spin_unlock_irq(&busiest_rq->lock);
return 0;
}
static DEFINE_SPINLOCK(hmp_force_migration);
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
/*
* Heterogenous Multi-Processor (HMP) Global Load Balance
*/
/*
* According to Linaro's comment, we should only check the currently running
* tasks because selecting other tasks for migration will require extensive
* book keeping.
*/
#ifdef CONFIG_HMP_GLOBAL_BALANCE
static void hmp_force_down_migration(int this_cpu)
{
int curr_cpu, target_cpu;
struct sched_entity *se;
struct rq *target;
unsigned long flags;
unsigned int force;
struct task_struct *p;
struct clb_env clbenv;
/* Migrate light task from big to LITTLE */
for_each_cpu(curr_cpu, &hmp_fast_cpu_mask) {
/* Check whether CPU is online */
if(!cpu_online(curr_cpu))
continue;
force = 0;
target = cpu_rq(curr_cpu);
raw_spin_lock_irqsave(&target->lock, flags);
se = target->cfs.curr;
if (!se) {
raw_spin_unlock_irqrestore(&target->lock, flags);
continue;
}
/* Find task entity */
if (!entity_is_task(se)) {
struct cfs_rq *cfs_rq;
cfs_rq = group_cfs_rq(se);
while (cfs_rq) {
se = cfs_rq->curr;
cfs_rq = group_cfs_rq(se);
}
}
p = task_of(se);
target_cpu = hmp_select_cpu(HMP_GB,p,&hmp_slow_cpu_mask,-1);
if(NR_CPUS == target_cpu) {
raw_spin_unlock_irqrestore(&target->lock, flags);
continue;
}
/* Collect cluster information */
memset(&clbenv, 0, sizeof(clbenv));
clbenv.flags |= HMP_GB;
clbenv.btarget = curr_cpu;
clbenv.ltarget = target_cpu;
clbenv.lcpus = &hmp_slow_cpu_mask;
clbenv.bcpus = &hmp_fast_cpu_mask;
sched_update_clbstats(&clbenv);
/* Check migration threshold */
if (!target->active_balance &&
hmp_down_migration(curr_cpu, &target_cpu, se, &clbenv)) {
target->active_balance = 1;
target->push_cpu = target_cpu;
target->migrate_task = p;
force = 1;
trace_sched_hmp_migrate(p, target->push_cpu, 1);
hmp_next_down_delay(&p->se, target->push_cpu);
}
raw_spin_unlock_irqrestore(&target->lock, flags);
if (force) {
stop_one_cpu_nowait(cpu_of(target),
hmp_active_task_migration_cpu_stop,
target, &target->active_balance_work);
}
}
}
#endif /* CONFIG_HMP_GLOBAL_BALANCE */
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
u32 AVOID_FORCE_UP_MIGRATION_FROM_CPUX_TO_CPUY_COUNT[NR_CPUS][NR_CPUS];
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
static void hmp_force_up_migration(int this_cpu)
{
int curr_cpu, target_cpu;
struct sched_entity *se;
struct rq *target;
unsigned long flags;
unsigned int force;
struct task_struct *p;
struct clb_env clbenv;
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
int push_cpu;
#endif
if (!spin_trylock(&hmp_force_migration))
return;
#ifdef CONFIG_HMP_TRACER
for_each_online_cpu(curr_cpu)
trace_sched_cfs_runnable_load(curr_cpu,cfs_load(curr_cpu),
cfs_length(curr_cpu));
#endif
/* Migrate heavy task from LITTLE to big */
for_each_cpu(curr_cpu, &hmp_slow_cpu_mask) {
/* Check whether CPU is online */
if(!cpu_online(curr_cpu))
continue;
force = 0;
target = cpu_rq(curr_cpu);
raw_spin_lock_irqsave(&target->lock, flags);
se = target->cfs.curr;
if (!se) {
raw_spin_unlock_irqrestore(&target->lock, flags);
continue;
}
/* Find task entity */
if (!entity_is_task(se)) {
struct cfs_rq *cfs_rq;
cfs_rq = group_cfs_rq(se);
while (cfs_rq) {
se = cfs_rq->curr;
cfs_rq = group_cfs_rq(se);
}
}
p = task_of(se);
target_cpu = hmp_select_cpu(HMP_GB,p,&hmp_fast_cpu_mask,-1);
if(NR_CPUS == target_cpu) {
raw_spin_unlock_irqrestore(&target->lock, flags);
continue;
}
/* Collect cluster information */
memset(&clbenv, 0, sizeof(clbenv));
clbenv.flags |= HMP_GB;
clbenv.ltarget = curr_cpu;
clbenv.btarget = target_cpu;
clbenv.lcpus = &hmp_slow_cpu_mask;
clbenv.bcpus = &hmp_fast_cpu_mask;
sched_update_clbstats(&clbenv);
#ifdef CONFIG_HMP_LAZY_BALANCE
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
if (PA_ENABLE && LB_ENABLE) {
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
if (is_light_task(p) && !is_buddy_busy(per_cpu(sd_pack_buddy, curr_cpu))) {
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
push_cpu = hmp_select_cpu(HMP_GB,p,&hmp_fast_cpu_mask,-1);
if (hmp_cpu_is_fast(push_cpu)) {
AVOID_FORCE_UP_MIGRATION_FROM_CPUX_TO_CPUY_COUNT[curr_cpu][push_cpu]++;
#ifdef CONFIG_HMP_TRACER
trace_sched_power_aware_active(POWER_AWARE_ACTIVE_MODULE_AVOID_FORCE_UP_FORM_CPUX_TO_CPUY, p->pid, curr_cpu, push_cpu);
#endif /* CONFIG_HMP_TRACER */
}
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
goto out_force_up;
}
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
}
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
#endif /* CONFIG_HMP_LAZY_BALANCE */
/* Check migration threshold */
if (!target->active_balance &&
hmp_up_migration(curr_cpu, &target_cpu, se, &clbenv)) {
target->active_balance = 1;
target->push_cpu = target_cpu;
target->migrate_task = p;
force = 1;
trace_sched_hmp_migrate(p, target->push_cpu, 1);
hmp_next_up_delay(&p->se, target->push_cpu);
}
#ifdef CONFIG_HMP_LAZY_BALANCE
out_force_up:
#endif /* CONFIG_HMP_LAZY_BALANCE */
raw_spin_unlock_irqrestore(&target->lock, flags);
if (force) {
stop_one_cpu_nowait(cpu_of(target),
hmp_active_task_migration_cpu_stop,
target, &target->active_balance_work);
}
}
#ifdef CONFIG_HMP_GLOBAL_BALANCE
hmp_force_down_migration(this_cpu);
#endif
#ifdef CONFIG_HMP_TRACER
trace_sched_hmp_load(clbenv.bstats.load_avg, clbenv.lstats.load_avg);
#endif
spin_unlock(&hmp_force_migration);
}
#else /* CONFIG_SCHED_HMP_ENHANCEMENT */
/*
* hmp_force_up_migration checks runqueues for tasks that need to
* be actively migrated to a faster cpu.
*/
static void hmp_force_up_migration(int this_cpu)
{
int cpu, target_cpu;
struct sched_entity *curr;
struct rq *target;
unsigned long flags;
unsigned int force;
struct task_struct *p;
if (!spin_trylock(&hmp_force_migration))
return;
for_each_online_cpu(cpu) {
force = 0;
target = cpu_rq(cpu);
raw_spin_lock_irqsave(&target->lock, flags);
curr = target->cfs.curr;
if (!curr) {
raw_spin_unlock_irqrestore(&target->lock, flags);
continue;
}
if (!entity_is_task(curr)) {
struct cfs_rq *cfs_rq;
cfs_rq = group_cfs_rq(curr);
while (cfs_rq) {
curr = cfs_rq->curr;
cfs_rq = group_cfs_rq(curr);
}
}
p = task_of(curr);
if (hmp_up_migration(cpu, &target_cpu, curr)) {
if (!target->active_balance) {
target->active_balance = 1;
target->push_cpu = target_cpu;
target->migrate_task = p;
force = 1;
trace_sched_hmp_migrate(p, target->push_cpu, 1);
hmp_next_up_delay(&p->se, target->push_cpu);
}
}
if (!force && !target->active_balance) {
/*
* For now we just check the currently running task.
* Selecting the lightest task for offloading will
* require extensive book keeping.
*/
target->push_cpu = hmp_offload_down(cpu, curr);
if (target->push_cpu < NR_CPUS) {
target->active_balance = 1;
target->migrate_task = p;
force = 1;
trace_sched_hmp_migrate(p, target->push_cpu, 2);
hmp_next_down_delay(&p->se, target->push_cpu);
}
}
raw_spin_unlock_irqrestore(&target->lock, flags);
if (force)
stop_one_cpu_nowait(cpu_of(target),
hmp_active_task_migration_cpu_stop,
target, &target->active_balance_work);
}
spin_unlock(&hmp_force_migration);
}
#endif /* CONFIG_SCHED_HMP_ENHANCEMENT */
#else
static void hmp_force_up_migration(int this_cpu) { }
#endif /* CONFIG_SCHED_HMP */
/*
* run_rebalance_domains is triggered when needed from the scheduler tick.
* Also triggered for nohz idle balancing (with nohz_balancing_kick set).
*/
static void run_rebalance_domains(struct softirq_action *h)
{
int this_cpu = smp_processor_id();
struct rq *this_rq = cpu_rq(this_cpu);
enum cpu_idle_type idle = this_rq->idle_balance ?
CPU_IDLE : CPU_NOT_IDLE;
hmp_force_up_migration(this_cpu);
rebalance_domains(this_cpu, idle);
/*
* If this cpu has a pending nohz_balance_kick, then do the
* balancing on behalf of the other idle cpus whose ticks are
* stopped.
*/
nohz_idle_balance(this_cpu, idle);
}
static inline int on_null_domain(int cpu)
{
return !rcu_dereference_sched(cpu_rq(cpu)->sd);
}
/*
* Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
*/
void trigger_load_balance(struct rq *rq, int cpu)
{
/* Don't need to rebalance while attached to NULL domain */
if (time_after_eq(jiffies, rq->next_balance) &&
likely(!on_null_domain(cpu)))
raise_softirq(SCHED_SOFTIRQ);
#ifdef CONFIG_NO_HZ_COMMON
if (nohz_kick_needed(rq, cpu) && likely(!on_null_domain(cpu)))
nohz_balancer_kick(cpu);
#endif
}
static void rq_online_fair(struct rq *rq)
{
#ifdef CONFIG_SCHED_HMP
hmp_online_cpu(rq->cpu);
#endif
update_sysctl();
}
static void rq_offline_fair(struct rq *rq)
{
#ifdef CONFIG_SCHED_HMP
hmp_offline_cpu(rq->cpu);
#endif
update_sysctl();
/* Ensure any throttled groups are reachable by pick_next_task */
unthrottle_offline_cfs_rqs(rq);
}
#endif /* CONFIG_SMP */
/*
* scheduler tick hitting a task of our scheduling class:
*/
static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued)
{
struct cfs_rq *cfs_rq;
struct sched_entity *se = &curr->se;
for_each_sched_entity(se) {
cfs_rq = cfs_rq_of(se);
entity_tick(cfs_rq, se, queued);
}
if (sched_feat_numa(NUMA))
task_tick_numa(rq, curr);
update_rq_runnable_avg(rq, 1);
}
/*
* called on fork with the child task as argument from the parent's context
* - child not yet on the tasklist
* - preemption disabled
*/
static void task_fork_fair(struct task_struct *p)
{
struct cfs_rq *cfs_rq;
struct sched_entity *se = &p->se, *curr;
int this_cpu = smp_processor_id();
struct rq *rq = this_rq();
unsigned long flags;
raw_spin_lock_irqsave(&rq->lock, flags);
update_rq_clock(rq);
cfs_rq = task_cfs_rq(current);
curr = cfs_rq->curr;
/*
* Not only the cpu but also the task_group of the parent might have
* been changed after parent->se.parent,cfs_rq were copied to
* child->se.parent,cfs_rq. So call __set_task_cpu() to make those
* of child point to valid ones.
*/
rcu_read_lock();
__set_task_cpu(p, this_cpu);
rcu_read_unlock();
update_curr(cfs_rq);
if (curr)
se->vruntime = curr->vruntime;
place_entity(cfs_rq, se, 1);
if (sysctl_sched_child_runs_first && curr && entity_before(curr, se)) {
/*
* Upon rescheduling, sched_class::put_prev_task() will place
* 'current' within the tree based on its new key value.
*/
swap(curr->vruntime, se->vruntime);
resched_task(rq->curr);
}
se->vruntime -= cfs_rq->min_vruntime;
raw_spin_unlock_irqrestore(&rq->lock, flags);
}
/*
* Priority of the task has changed. Check to see if we preempt
* the current task.
*/
static void
prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio)
{
if (!p->se.on_rq)
return;
/*
* Reschedule if we are currently running on this runqueue and
* our priority decreased, or if we are not currently running on
* this runqueue and our priority is higher than the current's
*/
if (rq->curr == p) {
if (p->prio > oldprio)
resched_task(rq->curr);
} else
check_preempt_curr(rq, p, 0);
}
static void switched_from_fair(struct rq *rq, struct task_struct *p)
{
struct sched_entity *se = &p->se;
struct cfs_rq *cfs_rq = cfs_rq_of(se);
/*
* Ensure the task's vruntime is normalized, so that when it's
* switched back to the fair class the enqueue_entity(.flags=0) will
* do the right thing.
*
* If it's on_rq, then the dequeue_entity(.flags=0) will already
* have normalized the vruntime, if it's !on_rq, then only when
* the task is sleeping will it still have non-normalized vruntime.
*/
if (!p->on_rq && p->state != TASK_RUNNING) {
/*
* Fix up our vruntime so that the current sleep doesn't
* cause 'unlimited' sleep bonus.
*/
place_entity(cfs_rq, se, 0);
se->vruntime -= cfs_rq->min_vruntime;
}
#ifdef CONFIG_SMP
/*
* Remove our load from contribution when we leave sched_fair
* and ensure we don't carry in an old decay_count if we
* switch back.
*/
if (p->se.avg.decay_count) {
struct cfs_rq *cfs_rq = cfs_rq_of(&p->se);
__synchronize_entity_decay(&p->se);
subtract_blocked_load_contrib(cfs_rq,
p->se.avg.load_avg_contrib);
}
#endif
}
/*
* We switched to the sched_fair class.
*/
static void switched_to_fair(struct rq *rq, struct task_struct *p)
{
if (!p->se.on_rq)
return;
/*
* We were most likely switched from sched_rt, so
* kick off the schedule if running, otherwise just see
* if we can still preempt the current task.
*/
if (rq->curr == p)
resched_task(rq->curr);
else{
/*
When task p change priority form RT to normal priority
in switch_from_rt(), it might call pull_rt_task
and potentially double_lock_balance will unlock rq.
Task p might migrate to other CPU and result in task p is NOT at rq.
In this case, it is not necessary to check preempt for rq.
(Because task p is NOT at rq anymore)
and the migrate flow for task p will check preempt in enqueue flow.
So bypass the check_preempt_curr.
*/
if (rq == task_rq(p)) {
check_preempt_curr(rq, p, 0);
}
}
}
/* Account for a task changing its policy or group.
*
* This routine is mostly called to set cfs_rq->curr field when a task
* migrates between groups/classes.
*/
static void set_curr_task_fair(struct rq *rq)
{
struct sched_entity *se = &rq->curr->se;
for_each_sched_entity(se) {
struct cfs_rq *cfs_rq = cfs_rq_of(se);
set_next_entity(cfs_rq, se);
/* ensure bandwidth has been allocated on our new cfs_rq */
account_cfs_rq_runtime(cfs_rq, 0);
}
}
void init_cfs_rq(struct cfs_rq *cfs_rq)
{
cfs_rq->tasks_timeline = RB_ROOT;
cfs_rq->min_vruntime = (u64)(-(1LL << 20));
#ifndef CONFIG_64BIT
cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime;
#endif
#ifdef CONFIG_SMP
atomic64_set(&cfs_rq->decay_counter, 1);
atomic_long_set(&cfs_rq->removed_load, 0);
#endif
}
#ifdef CONFIG_FAIR_GROUP_SCHED
static void task_move_group_fair(struct task_struct *p, int on_rq)
{
struct cfs_rq *cfs_rq;
/*
* If the task was not on the rq at the time of this cgroup movement
* it must have been asleep, sleeping tasks keep their ->vruntime
* absolute on their old rq until wakeup (needed for the fair sleeper
* bonus in place_entity()).
*
* If it was on the rq, we've just 'preempted' it, which does convert
* ->vruntime to a relative base.
*
* Make sure both cases convert their relative position when migrating
* to another cgroup's rq. This does somewhat interfere with the
* fair sleeper stuff for the first placement, but who cares.
*/
/*
* When !on_rq, vruntime of the task has usually NOT been normalized.
* But there are some cases where it has already been normalized:
*
* - Moving a forked child which is waiting for being woken up by
* wake_up_new_task().
* - Moving a task which has been woken up by try_to_wake_up() and
* waiting for actually being woken up by sched_ttwu_pending().
*
* To prevent boost or penalty in the new cfs_rq caused by delta
* min_vruntime between the two cfs_rqs, we skip vruntime adjustment.
*/
if (!on_rq && (!p->se.sum_exec_runtime || p->state == TASK_WAKING))
on_rq = 1;
if (!on_rq)
p->se.vruntime -= cfs_rq_of(&p->se)->min_vruntime;
set_task_rq(p, task_cpu(p));
if (!on_rq) {
cfs_rq = cfs_rq_of(&p->se);
p->se.vruntime += cfs_rq->min_vruntime;
#ifdef CONFIG_SMP
/*
* migrate_task_rq_fair() will have removed our previous
* contribution, but we must synchronize for ongoing future
* decay.
*/
p->se.avg.decay_count = atomic64_read(&cfs_rq->decay_counter);
cfs_rq->blocked_load_avg += p->se.avg.load_avg_contrib;
#endif
}
}
void free_fair_sched_group(struct task_group *tg)
{
int i;
destroy_cfs_bandwidth(tg_cfs_bandwidth(tg));
for_each_possible_cpu(i) {
if (tg->cfs_rq)
kfree(tg->cfs_rq[i]);
if (tg->se)
kfree(tg->se[i]);
}
kfree(tg->cfs_rq);
kfree(tg->se);
}
int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
{
struct cfs_rq *cfs_rq;
struct sched_entity *se;
int i;
tg->cfs_rq = kzalloc(sizeof(cfs_rq) * nr_cpu_ids, GFP_KERNEL);
if (!tg->cfs_rq)
goto err;
tg->se = kzalloc(sizeof(se) * nr_cpu_ids, GFP_KERNEL);
if (!tg->se)
goto err;
tg->shares = NICE_0_LOAD;
init_cfs_bandwidth(tg_cfs_bandwidth(tg));
for_each_possible_cpu(i) {
cfs_rq = kzalloc_node(sizeof(struct cfs_rq),
GFP_KERNEL, cpu_to_node(i));
if (!cfs_rq)
goto err;
se = kzalloc_node(sizeof(struct sched_entity),
GFP_KERNEL, cpu_to_node(i));
if (!se)
goto err_free_rq;
init_cfs_rq(cfs_rq);
init_tg_cfs_entry(tg, cfs_rq, se, i, parent->se[i]);
}
return 1;
err_free_rq:
kfree(cfs_rq);
err:
return 0;
}
void unregister_fair_sched_group(struct task_group *tg, int cpu)
{
struct rq *rq = cpu_rq(cpu);
unsigned long flags;
/*
* Only empty task groups can be destroyed; so we can speculatively
* check on_list without danger of it being re-added.
*/
if (!tg->cfs_rq[cpu]->on_list)
return;
raw_spin_lock_irqsave(&rq->lock, flags);
list_del_leaf_cfs_rq(tg->cfs_rq[cpu]);
raw_spin_unlock_irqrestore(&rq->lock, flags);
}
void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
struct sched_entity *se, int cpu,
struct sched_entity *parent)
{
struct rq *rq = cpu_rq(cpu);
cfs_rq->tg = tg;
cfs_rq->rq = rq;
init_cfs_rq_runtime(cfs_rq);
tg->cfs_rq[cpu] = cfs_rq;
tg->se[cpu] = se;
/* se could be NULL for root_task_group */
if (!se)
return;
if (!parent)
se->cfs_rq = &rq->cfs;
else
se->cfs_rq = parent->my_q;
se->my_q = cfs_rq;
/* guarantee group entities always have weight */
update_load_set(&se->load, NICE_0_LOAD);
se->parent = parent;
}
static DEFINE_MUTEX(shares_mutex);
int sched_group_set_shares(struct task_group *tg, unsigned long shares)
{
int i;
unsigned long flags;
/*
* We can't change the weight of the root cgroup.
*/
if (!tg->se[0])
return -EINVAL;
shares = clamp(shares, scale_load(MIN_SHARES), scale_load(MAX_SHARES));
mutex_lock(&shares_mutex);
if (tg->shares == shares)
goto done;
tg->shares = shares;
for_each_possible_cpu(i) {
struct rq *rq = cpu_rq(i);
struct sched_entity *se;
se = tg->se[i];
/* Propagate contribution to hierarchy */
raw_spin_lock_irqsave(&rq->lock, flags);
for_each_sched_entity(se)
update_cfs_shares(group_cfs_rq(se));
raw_spin_unlock_irqrestore(&rq->lock, flags);
}
done:
mutex_unlock(&shares_mutex);
return 0;
}
#else /* CONFIG_FAIR_GROUP_SCHED */
void free_fair_sched_group(struct task_group *tg) { }
int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
{
return 1;
}
void unregister_fair_sched_group(struct task_group *tg, int cpu) { }
#endif /* CONFIG_FAIR_GROUP_SCHED */
static unsigned int get_rr_interval_fair(struct rq *rq, struct task_struct *task)
{
struct sched_entity *se = &task->se;
unsigned int rr_interval = 0;
/*
* Time slice is 0 for SCHED_OTHER tasks that are on an otherwise
* idle runqueue:
*/
if (rq->cfs.load.weight)
rr_interval = NS_TO_JIFFIES(sched_slice(cfs_rq_of(se), se));
return rr_interval;
}
/*
* All the scheduling class methods:
*/
const struct sched_class fair_sched_class = {
.next = &idle_sched_class,
.enqueue_task = enqueue_task_fair,
.dequeue_task = dequeue_task_fair,
.yield_task = yield_task_fair,
.yield_to_task = yield_to_task_fair,
.check_preempt_curr = check_preempt_wakeup,
.pick_next_task = pick_next_task_fair,
.put_prev_task = put_prev_task_fair,
#ifdef CONFIG_SMP
.select_task_rq = select_task_rq_fair,
.migrate_task_rq = migrate_task_rq_fair,
.rq_online = rq_online_fair,
.rq_offline = rq_offline_fair,
.task_waking = task_waking_fair,
#endif
.set_curr_task = set_curr_task_fair,
.task_tick = task_tick_fair,
.task_fork = task_fork_fair,
.prio_changed = prio_changed_fair,
.switched_from = switched_from_fair,
.switched_to = switched_to_fair,
.get_rr_interval = get_rr_interval_fair,
#ifdef CONFIG_FAIR_GROUP_SCHED
.task_move_group = task_move_group_fair,
#endif
};
#ifdef CONFIG_SCHED_DEBUG
void print_cfs_stats(struct seq_file *m, int cpu)
{
struct cfs_rq *cfs_rq;
rcu_read_lock();
for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq)
print_cfs_rq(m, cpu, cfs_rq);
rcu_read_unlock();
}
#endif
__init void init_sched_fair_class(void)
{
#ifdef CONFIG_SMP
open_softirq(SCHED_SOFTIRQ, run_rebalance_domains);
#ifdef CONFIG_NO_HZ_COMMON
nohz.next_balance = jiffies;
zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT);
cpu_notifier(sched_ilb_notifier, 0);
#endif
cmp_cputopo_domain_setup();
#ifdef CONFIG_SCHED_HMP
hmp_cpu_mask_setup();
#endif
#endif /* SMP */
}
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
static u32 cpufreq_calc_scale(u32 min, u32 max, u32 curr)
{
u32 result = curr / max;
return result;
}
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
DEFINE_PER_CPU(u32, FREQ_CPU);
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
/* Called when the CPU Frequency is changed.
* Once for each CPU.
*/
static int cpufreq_callback(struct notifier_block *nb,
unsigned long val, void *data)
{
struct cpufreq_freqs *freq = data;
int cpu = freq->cpu;
struct cpufreq_extents *extents;
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
struct cpumask* mask;
int id;
#endif
if (freq->flags & CPUFREQ_CONST_LOOPS)
return NOTIFY_OK;
if (val != CPUFREQ_POSTCHANGE)
return NOTIFY_OK;
/* if dynamic load scale is disabled, set the load scale to 1.0 */
if (!hmp_data.freqinvar_load_scale_enabled) {
freq_scale[cpu].curr_scale = 1024;
return NOTIFY_OK;
}
extents = &freq_scale[cpu];
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
if (extents->max < extents->const_max){
extents->throttling=1;
}
else {
extents->throttling=0;
}
#endif
if (extents->flags & SCHED_LOAD_FREQINVAR_SINGLEFREQ) {
/* If our governor was recognised as a single-freq governor,
* use 1.0
*/
extents->curr_scale = 1024;
} else {
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
extents->curr_scale = cpufreq_calc_scale(extents->min,
extents->const_max, freq->new);
#else
extents->curr_scale = cpufreq_calc_scale(extents->min,
extents->max, freq->new);
#endif
}
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
mask = arch_cpu_is_big(cpu)?&hmp_fast_cpu_mask:&hmp_slow_cpu_mask;
for_each_cpu(id, mask)
freq_scale[id].curr_scale = extents->curr_scale;
#endif
#if NR_CPUS == 4
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
switch (cpu) {
case 0:
case 2:
(extents + 1)->curr_scale = extents->curr_scale;
break;
case 1:
case 3:
(extents - 1)->curr_scale = extents->curr_scale;
break;
default:
break;
}
#endif
#endif
#ifdef CONFIG_HMP_POWER_AWARE_CONTROLLER
per_cpu(FREQ_CPU, cpu) = freq->new;
#endif /* CONFIG_HMP_POWER_AWARE_CONTROLLER */
return NOTIFY_OK;
}
/* Called when the CPUFreq governor is changed.
* Only called for the CPUs which are actually changed by the
* userspace.
*/
static int cpufreq_policy_callback(struct notifier_block *nb,
unsigned long event, void *data)
{
struct cpufreq_policy *policy = data;
struct cpufreq_extents *extents;
int cpu, singleFreq = 0;
static const char performance_governor[] = "performance";
static const char powersave_governor[] = "powersave";
if (event == CPUFREQ_START)
return 0;
if (event != CPUFREQ_INCOMPATIBLE)
return 0;
/* CPUFreq governors do not accurately report the range of
* CPU Frequencies they will choose from.
* We recognise performance and powersave governors as
* single-frequency only.
*/
if (!strncmp(policy->governor->name, performance_governor,
strlen(performance_governor)) ||
!strncmp(policy->governor->name, powersave_governor,
strlen(powersave_governor)))
singleFreq = 1;
/* Make sure that all CPUs impacted by this policy are
* updated since we will only get a notification when the
* user explicitly changes the policy on a CPU.
*/
for_each_cpu(cpu, policy->cpus) {
extents = &freq_scale[cpu];
extents->max = policy->max >> SCHED_FREQSCALE_SHIFT;
extents->min = policy->min >> SCHED_FREQSCALE_SHIFT;
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
extents->const_max = policy->cpuinfo.max_freq >> SCHED_FREQSCALE_SHIFT;
#endif
if (!hmp_data.freqinvar_load_scale_enabled) {
extents->curr_scale = 1024;
} else if (singleFreq) {
extents->flags |= SCHED_LOAD_FREQINVAR_SINGLEFREQ;
extents->curr_scale = 1024;
} else {
extents->flags &= ~SCHED_LOAD_FREQINVAR_SINGLEFREQ;
#ifdef CONFIG_SCHED_HMP_ENHANCEMENT
extents->curr_scale = cpufreq_calc_scale(extents->min,
extents->const_max, policy->cur);
#else
extents->curr_scale = cpufreq_calc_scale(extents->min,
extents->max, policy->cur);
#endif
}
}
return 0;
}
static struct notifier_block cpufreq_notifier = {
.notifier_call = cpufreq_callback,
};
static struct notifier_block cpufreq_policy_notifier = {
.notifier_call = cpufreq_policy_callback,
};
static int __init register_sched_cpufreq_notifier(void)
{
int ret = 0;
/* init safe defaults since there are no policies at registration */
for (ret = 0; ret < CONFIG_NR_CPUS; ret++) {
/* safe defaults */
freq_scale[ret].max = 1024;
freq_scale[ret].min = 1024;
freq_scale[ret].curr_scale = 1024;
}
pr_info("sched: registering cpufreq notifiers for scale-invariant loads\n");
ret = cpufreq_register_notifier(&cpufreq_policy_notifier,
CPUFREQ_POLICY_NOTIFIER);
if (ret != -EINVAL)
ret = cpufreq_register_notifier(&cpufreq_notifier,
CPUFREQ_TRANSITION_NOTIFIER);
return ret;
}
core_initcall(register_sched_cpufreq_notifier);
#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
#ifdef CONFIG_HEVTASK_INTERFACE
/*
* * This allows printing both to /proc/task_detect and
* * to the console
* */
#ifndef CONFIG_KGDB_KDB
#define SEQ_printf(m, x...) \
do { \
if (m) \
seq_printf(m, x); \
else \
printk(x); \
} while (0)
#else
#define SEQ_printf(m, x...) \
do { \
if (m) \
seq_printf(m, x); \
else if (__get_cpu_var(kdb_in_use) == 1) \
kdb_printf(x); \
else \
printk(x); \
} while (0)
#endif
static int task_detect_show(struct seq_file *m, void *v)
{
struct task_struct *p;
unsigned long flags;
unsigned int i;
#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
for(i=0;i<NR_CPUS;i++){
SEQ_printf(m,"%5d ",freq_scale[i].curr_scale);
}
#endif
SEQ_printf(m, "\n%lu\n ",jiffies_to_cputime(jiffies));
for(i=0;i<NR_CPUS;i++){
raw_spin_lock_irqsave(&cpu_rq(i)->lock,flags);
if(cpu_online(i)){
list_for_each_entry(p,&cpu_rq(i)->cfs_tasks,se.group_node){
SEQ_printf(m, "%lu %5d %5d %lu (%15s)\n ",
p->se.avg.load_avg_ratio,p->pid,task_cpu(p),
(p->utime+p->stime),p->comm);
}
}
raw_spin_unlock_irqrestore(&cpu_rq(i)->lock,flags);
}
return 0;
}
static int task_detect_open(struct inode *inode, struct file *filp)
{
return single_open(filp, task_detect_show, NULL);
}
static const struct file_operations task_detect_fops = {
.open = task_detect_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int __init init_task_detect_procfs(void)
{
struct proc_dir_entry *pe;
pe = proc_create("task_detect", 0444, NULL, &task_detect_fops);
if (!pe)
return -ENOMEM;
return 0;
}
__initcall(init_task_detect_procfs);
#endif /* CONFIG_HEVTASK_INTERFACE */
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