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(host81-157-90-255.range81-157.btcentralplus.com. [81.157.90.255]) by smtp.gmail.com with ESMTPSA id r13-20020a5d694d000000b0034c926ef66csm9198659wrw.51.2024.05.05.16.31.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 05 May 2024 16:31:20 -0700 (PDT) From: Qais Yousef To: "Rafael J. Wysocki" , Viresh Kumar , Ingo Molnar , Peter Zijlstra , Vincent Guittot , Juri Lelli Cc: Steven Rostedt , Dietmar Eggemann , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Valentin Schneider , Christian Loehle , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Qais Yousef Subject: [PATCH v2] sched: Consolidate cpufreq updates Date: Mon, 6 May 2024 00:31:03 +0100 Message-Id: <20240505233103.168766-1-qyousef@layalina.io> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Improve the interaction with cpufreq governors by making the cpufreq_update_util() calls more intentional. At the moment we send them when load is updated for CFS, bandwidth for DL and at enqueue/dequeue for RT. But this can lead to too many updates sent in a short period of time and potentially be ignored at a critical moment due to the rate_limit_us in schedutil. For example, simultaneous task enqueue on the CPU where 2nd task is bigger and requires higher freq. The trigger to cpufreq_update_util() by the first task will lead to dropping the 2nd request until tick. Or another CPU in the same policy triggers a freq update shortly after. Updates at enqueue for RT are not strictly required. Though they do help to reduce the delay for switching the frequency and the potential observation of lower frequency during this delay. But current logic doesn't intentionally (at least to my understanding) try to speed up the request. To help reduce the amount of cpufreq updates and make them more purposeful, consolidate them into these locations: 1. context_switch() 2. task_tick_fair() 3. {attach, detach}_entity_load_avg() 4. update_blocked_averages() The update at context switch should help guarantee that DL and RT get the right frequency straightaway when they're RUNNING. As mentioned though the update will happen slightly after enqueue_task(); though in an ideal world these tasks should be RUNNING ASAP and this additional delay should be negligible. For fair tasks we need to make sure we send a single update for every decay for the root cfs_rq. Any changes to the rq will be deferred until the next task is ready to run, or we hit TICK. But we are guaranteed the task is running at a level that meets its requirements after enqueue. To guarantee RT and DL tasks updates are never missed, we add a new SCHED_CPUFREQ_FORCE_UPDATE to ignore the rate_limit_us. If we are already running at the right freq, the governor will end up doing nothing, but we eliminate the risk of the task ending up accidentally running at the wrong freq due to rate_limit_us. Similarly for iowait boost, we ignore rate limits. We also handle a case of a boost reset prematurely by adding a guard in sugov_iowait_apply() to reduce the boost after 1ms which seems iowait boost mechanism relied on rate_limit_us and cfs_rq.decay preventing any updates to happen soon after iowait boost. The new SCHED_CPUFREQ_FORCE_UPDATE should not impact the rate limit time stamps otherwise we can end up delaying updates for normal requests. As a simple optimization, we avoid sending cpufreq updates when switching from RT to another RT as RT tasks run at max freq by default. If CONFIG_UCLAMP_TASK is enabled, we can do a simple check to see if uclamp_min is different to avoid unnecessary cpufreq update as most RT tasks are likely to be running at the same performance level, so we can avoid unnecessary overhead of forced updates when there's nothing to do. We also also ensure to ignore cpufreq udpates for sugov workers at context switch. It doesn't make sense for the kworker that applies the frequency update (which is a DL task) to trigger a frequency update itself. The update at task_tick_fair will guarantee that the governor will follow any updates to load for tasks/CPU or due to new enqueues/dequeues to the rq. Since DL and RT always run at constant frequencies and have no load tracking, this is only required for fair tasks. The update at attach/detach_entity_load_avg() will ensure we adapt to big changes when tasks are added/removed from cgroups. The update at update_blocked_averages() will ensure we decay frequency as the CPU becomes idle for long enough. Results of taskset 1 perf stat --repeat 10 -e cycles,instructions,task-clock perf bench sched pipe on AMD 3900X to verify any potential overhead because of the addition at context switch against v6.8.7 stable kernel v6.8.7: schedutil: ------------------ Performance counter stats for 'perf bench sched pipe' (10 runs): 850,276,689 cycles:u # 0.078 GHz ( +- 0.88% ) 82,724,245 instructions:u # 0.10 insn per cycle ( +- 0.00% ) 10,881.41 msec task-clock:u # 0.995 CPUs utilized ( +- 0.12% ) 10.9377 +- 0.0135 seconds time elapsed ( +- 0.12% ) v6.8.7: performance: -------------------- Performance counter stats for 'perf bench sched pipe' (10 runs): 874,154,415 cycles:u # 0.080 GHz ( +- 0.78% ) 82,724,420 instructions:u # 0.10 insn per cycle ( +- 0.00% ) 10,916.47 msec task-clock:u # 0.999 CPUs utilized ( +- 0.09% ) 10.9308 +- 0.0100 seconds time elapsed ( +- 0.09% ) v6.8.7+patch: schedutil: ------------------------ Performance counter stats for 'perf bench sched pipe' (10 runs): 816,938,281 cycles:u # 0.075 GHz ( +- 0.84% ) 82,724,163 instructions:u # 0.10 insn per cycle ( +- 0.00% ) 10,907.62 msec task-clock:u # 1.004 CPUs utilized ( +- 0.11% ) 10.8627 +- 0.0121 seconds time elapsed ( +- 0.11% ) v6.8.7+patch: performance: -------------------------- Performance counter stats for 'perf bench sched pipe' (10 runs): 814,038,416 cycles:u # 0.074 GHz ( +- 1.21% ) 82,724,356 instructions:u # 0.10 insn per cycle ( +- 0.00% ) 10,886.69 msec task-clock:u # 0.996 CPUs utilized ( +- 0.17% ) 10.9298 +- 0.0181 seconds time elapsed ( +- 0.17% ) Note worthy that we still have the following race condition on systems that have shared policy: * CPUs with shared policy can end up sending simultaneous cpufreq updates requests where the 2nd one will be unlucky and get blocked by the rate_limit_us (schedutil). We can potentially address this limitation later, but it is out of the scope of this patch. Signed-off-by: Qais Yousef --- Changes since v1: * Use taskset and measure with performance governor as Ingo suggested * Remove the static key as I found out we always register a function for cpu_dbs in cpufreq_governor.c; and as Christian pointed out it trigger a lock debug warning. * Improve detection of sugov workers by using SCHED_FLAG_SUGOV * Guard against NSEC_PER_MSEC instead of TICK_USEC to avoid prematurely reducing iowait boost as the latter was a NOP and like sugov_iowait_reset() like Christian pointed out. v1 discussion: https://lore.kernel.org/all/20240324020139.1032473-1-qyousef@layalina.io/ include/linux/sched/cpufreq.h | 3 +- kernel/sched/core.c | 68 +++++++++++++++++++++++++++++++- kernel/sched/cpufreq_schedutil.c | 55 +++++++++++++++++++------- kernel/sched/deadline.c | 4 -- kernel/sched/fair.c | 53 ++++--------------------- kernel/sched/rt.c | 8 +--- kernel/sched/sched.h | 5 +++ 7 files changed, 122 insertions(+), 74 deletions(-) diff --git a/include/linux/sched/cpufreq.h b/include/linux/sched/cpufreq.h index bdd31ab93bc5..2d0a45aba16f 100644 --- a/include/linux/sched/cpufreq.h +++ b/include/linux/sched/cpufreq.h @@ -8,7 +8,8 @@ * Interface between cpufreq drivers and the scheduler: */ -#define SCHED_CPUFREQ_IOWAIT (1U << 0) +#define SCHED_CPUFREQ_IOWAIT (1U << 0) +#define SCHED_CPUFREQ_FORCE_UPDATE (1U << 1) /* ignore transition_delay_us */ #ifdef CONFIG_CPU_FREQ struct cpufreq_policy; diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 1a914388144a..e6fe7dbd1f89 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5134,6 +5134,65 @@ static inline void balance_callbacks(struct rq *rq, struct balance_callback *hea #endif +static inline void update_cpufreq_ctx_switch(struct rq *rq, struct task_struct *prev) +{ +#ifdef CONFIG_CPU_FREQ + unsigned int flags = 0; + +#ifdef CONFIG_SMP + if (unlikely(current->sched_class == &stop_sched_class)) + return; +#endif + + if (unlikely(current->sched_class == &idle_sched_class)) + return; + + if (unlikely(task_has_idle_policy(current))) + return; + + if (likely(fair_policy(current->policy))) { + + if (unlikely(current->in_iowait)) { + flags |= SCHED_CPUFREQ_IOWAIT | SCHED_CPUFREQ_FORCE_UPDATE; + goto force_update; + } + +#ifdef CONFIG_SMP + /* + * Allow cpufreq updates once for every update_load_avg() decay. + */ + if (unlikely(rq->cfs.decayed)) { + rq->cfs.decayed = false; + goto force_update; + } +#endif + return; + } + + /* + * RT and DL should always send a freq update. But we can do some + * simple checks to avoid it when we know it's not necessary. + */ + if (rt_task(current) && rt_task(prev)) { +#ifdef CONFIG_UCLAMP_TASK + unsigned long curr_uclamp_min = uclamp_eff_value(current, UCLAMP_MIN); + unsigned long prev_uclamp_min = uclamp_eff_value(prev, UCLAMP_MIN); + + if (curr_uclamp_min == prev_uclamp_min) +#endif + return; + } else if (dl_task(current) && current->dl.flags & SCHED_FLAG_SUGOV) { + /* Ignore sugov kthreads, they're responding to our requests */ + return; + } + + flags |= SCHED_CPUFREQ_FORCE_UPDATE; + +force_update: + cpufreq_update_util(rq, flags); +#endif +} + static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next, struct rq_flags *rf) { @@ -5151,7 +5210,7 @@ prepare_lock_switch(struct rq *rq, struct task_struct *next, struct rq_flags *rf #endif } -static inline void finish_lock_switch(struct rq *rq) +static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) { /* * If we are tracking spinlock dependencies then we have to @@ -5160,6 +5219,11 @@ static inline void finish_lock_switch(struct rq *rq) */ spin_acquire(&__rq_lockp(rq)->dep_map, 0, 0, _THIS_IP_); __balance_callbacks(rq); + /* + * Request freq update after __balance_callbacks to take into account + * any changes to rq. + */ + update_cpufreq_ctx_switch(rq, prev); raw_spin_rq_unlock_irq(rq); } @@ -5278,7 +5342,7 @@ static struct rq *finish_task_switch(struct task_struct *prev) perf_event_task_sched_in(prev, current); finish_task(prev); tick_nohz_task_switch(); - finish_lock_switch(rq); + finish_lock_switch(rq, prev); finish_arch_post_lock_switch(); kcov_finish_switch(current); /* diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index eece6244f9d2..e8b65b75e7f3 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -59,7 +59,8 @@ static DEFINE_PER_CPU(struct sugov_cpu, sugov_cpu); /************************ Governor internals ***********************/ -static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time) +static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time, + unsigned int flags) { s64 delta_ns; @@ -87,13 +88,16 @@ static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time) return true; } + if (unlikely(flags & SCHED_CPUFREQ_FORCE_UPDATE)) + return true; + delta_ns = time - sg_policy->last_freq_update_time; return delta_ns >= sg_policy->freq_update_delay_ns; } static bool sugov_update_next_freq(struct sugov_policy *sg_policy, u64 time, - unsigned int next_freq) + unsigned int next_freq, unsigned int flags) { if (sg_policy->need_freq_update) sg_policy->need_freq_update = cpufreq_driver_test_flags(CPUFREQ_NEED_UPDATE_LIMITS); @@ -101,7 +105,9 @@ static bool sugov_update_next_freq(struct sugov_policy *sg_policy, u64 time, return false; sg_policy->next_freq = next_freq; - sg_policy->last_freq_update_time = time; + + if (!unlikely(flags & SCHED_CPUFREQ_FORCE_UPDATE)) + sg_policy->last_freq_update_time = time; return true; } @@ -249,9 +255,10 @@ static void sugov_iowait_boost(struct sugov_cpu *sg_cpu, u64 time, unsigned int flags) { bool set_iowait_boost = flags & SCHED_CPUFREQ_IOWAIT; + bool forced_update = flags & SCHED_CPUFREQ_FORCE_UPDATE; /* Reset boost if the CPU appears to have been idle enough */ - if (sg_cpu->iowait_boost && + if (sg_cpu->iowait_boost && !forced_update && sugov_iowait_reset(sg_cpu, time, set_iowait_boost)) return; @@ -294,17 +301,34 @@ static void sugov_iowait_boost(struct sugov_cpu *sg_cpu, u64 time, * being more conservative on tasks which does sporadic IO operations. */ static unsigned long sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time, - unsigned long max_cap) + unsigned long max_cap, unsigned int flags) { + bool forced_update = flags & SCHED_CPUFREQ_FORCE_UPDATE; + s64 delta_ns = time - sg_cpu->last_update; + /* No boost currently required */ if (!sg_cpu->iowait_boost) return 0; + if (forced_update) + goto apply_boost; + /* Reset boost if the CPU appears to have been idle enough */ if (sugov_iowait_reset(sg_cpu, time, false)) return 0; if (!sg_cpu->iowait_boost_pending) { + /* + * This logic relied on PELT signal decays happening once every + * 1ms. But due to changes to how updates are done now, we can + * end up with more request coming up leading to iowait boost + * to be prematurely reduced. Make the assumption explicit + * until we improve the iowait boost logic to be better in + * general as it is due for an overhaul. + */ + if (delta_ns <= NSEC_PER_MSEC) + goto apply_boost; + /* * No boost pending; reduce the boost value. */ @@ -315,6 +339,7 @@ static unsigned long sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time, } } +apply_boost: sg_cpu->iowait_boost_pending = false; /* @@ -358,10 +383,10 @@ static inline bool sugov_update_single_common(struct sugov_cpu *sg_cpu, ignore_dl_rate_limit(sg_cpu); - if (!sugov_should_update_freq(sg_cpu->sg_policy, time)) + if (!sugov_should_update_freq(sg_cpu->sg_policy, time, flags)) return false; - boost = sugov_iowait_apply(sg_cpu, time, max_cap); + boost = sugov_iowait_apply(sg_cpu, time, max_cap, flags); sugov_get_util(sg_cpu, boost); return true; @@ -397,7 +422,7 @@ static void sugov_update_single_freq(struct update_util_data *hook, u64 time, sg_policy->cached_raw_freq = cached_freq; } - if (!sugov_update_next_freq(sg_policy, time, next_f)) + if (!sugov_update_next_freq(sg_policy, time, next_f, flags)) return; /* @@ -449,10 +474,12 @@ static void sugov_update_single_perf(struct update_util_data *hook, u64 time, cpufreq_driver_adjust_perf(sg_cpu->cpu, sg_cpu->bw_min, sg_cpu->util, max_cap); - sg_cpu->sg_policy->last_freq_update_time = time; + if (!unlikely(flags & SCHED_CPUFREQ_FORCE_UPDATE)) + sg_cpu->sg_policy->last_freq_update_time = time; } -static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu, u64 time) +static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu, u64 time, + unsigned int flags) { struct sugov_policy *sg_policy = sg_cpu->sg_policy; struct cpufreq_policy *policy = sg_policy->policy; @@ -465,7 +492,7 @@ static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu, u64 time) struct sugov_cpu *j_sg_cpu = &per_cpu(sugov_cpu, j); unsigned long boost; - boost = sugov_iowait_apply(j_sg_cpu, time, max_cap); + boost = sugov_iowait_apply(j_sg_cpu, time, max_cap, flags); sugov_get_util(j_sg_cpu, boost); util = max(j_sg_cpu->util, util); @@ -488,10 +515,10 @@ sugov_update_shared(struct update_util_data *hook, u64 time, unsigned int flags) ignore_dl_rate_limit(sg_cpu); - if (sugov_should_update_freq(sg_policy, time)) { - next_f = sugov_next_freq_shared(sg_cpu, time); + if (sugov_should_update_freq(sg_policy, time, flags)) { + next_f = sugov_next_freq_shared(sg_cpu, time, flags); - if (!sugov_update_next_freq(sg_policy, time, next_f)) + if (!sugov_update_next_freq(sg_policy, time, next_f, flags)) goto unlock; if (sg_policy->policy->fast_switch_enabled) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index a04a436af8cc..02c9c2488091 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -252,8 +252,6 @@ void __add_running_bw(u64 dl_bw, struct dl_rq *dl_rq) dl_rq->running_bw += dl_bw; SCHED_WARN_ON(dl_rq->running_bw < old); /* overflow */ SCHED_WARN_ON(dl_rq->running_bw > dl_rq->this_bw); - /* kick cpufreq (see the comment in kernel/sched/sched.h). */ - cpufreq_update_util(rq_of_dl_rq(dl_rq), 0); } static inline @@ -266,8 +264,6 @@ void __sub_running_bw(u64 dl_bw, struct dl_rq *dl_rq) SCHED_WARN_ON(dl_rq->running_bw > old); /* underflow */ if (dl_rq->running_bw > old) dl_rq->running_bw = 0; - /* kick cpufreq (see the comment in kernel/sched/sched.h). */ - cpufreq_update_util(rq_of_dl_rq(dl_rq), 0); } static inline diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 9eb63573110c..cbe79c8ac2ed 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3982,29 +3982,6 @@ static inline void update_cfs_group(struct sched_entity *se) } #endif /* CONFIG_FAIR_GROUP_SCHED */ -static inline void cfs_rq_util_change(struct cfs_rq *cfs_rq, int flags) -{ - struct rq *rq = rq_of(cfs_rq); - - if (&rq->cfs == cfs_rq) { - /* - * There are a few boundary cases this might miss but it should - * get called often enough that that should (hopefully) not be - * a real problem. - * - * It will not get called when we go idle, because the idle - * thread is a different class (!fair), nor will the utilization - * number include things like RT tasks. - * - * As is, the util number is not freq-invariant (we'd have to - * implement arch_scale_freq_capacity() for that). - * - * See cpu_util_cfs(). - */ - cpufreq_update_util(rq, flags); - } -} - #ifdef CONFIG_SMP static inline bool load_avg_is_decayed(struct sched_avg *sa) { @@ -4682,7 +4659,7 @@ static void attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s add_tg_cfs_propagate(cfs_rq, se->avg.load_sum); - cfs_rq_util_change(cfs_rq, 0); + cpufreq_update_util(rq_of(cfs_rq), 0); trace_pelt_cfs_tp(cfs_rq); } @@ -4712,7 +4689,7 @@ static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s add_tg_cfs_propagate(cfs_rq, -se->avg.load_sum); - cfs_rq_util_change(cfs_rq, 0); + cpufreq_update_util(rq_of(cfs_rq), 0); trace_pelt_cfs_tp(cfs_rq); } @@ -4729,7 +4706,6 @@ static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s static inline void update_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags) { u64 now = cfs_rq_clock_pelt(cfs_rq); - int decayed; /* * Track task load average for carrying it to new CPU after migrated, and @@ -4738,8 +4714,8 @@ static inline void update_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s if (se->avg.last_update_time && !(flags & SKIP_AGE_LOAD)) __update_load_avg_se(now, cfs_rq, se); - decayed = update_cfs_rq_load_avg(now, cfs_rq); - decayed |= propagate_entity_load_avg(se); + cfs_rq->decayed = update_cfs_rq_load_avg(now, cfs_rq); + cfs_rq->decayed |= propagate_entity_load_avg(se); if (!se->avg.last_update_time && (flags & DO_ATTACH)) { @@ -4760,11 +4736,8 @@ static inline void update_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s */ detach_entity_load_avg(cfs_rq, se); update_tg_load_avg(cfs_rq); - } else if (decayed) { - cfs_rq_util_change(cfs_rq, 0); - - if (flags & UPDATE_TG) - update_tg_load_avg(cfs_rq); + } else if (cfs_rq->decayed && (flags & UPDATE_TG)) { + update_tg_load_avg(cfs_rq); } } @@ -5139,7 +5112,6 @@ static inline bool cfs_rq_is_decayed(struct cfs_rq *cfs_rq) static inline void update_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se, int not_used1) { - cfs_rq_util_change(cfs_rq, 0); } static inline void remove_entity_load_avg(struct sched_entity *se) {} @@ -6754,14 +6726,6 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags) */ util_est_enqueue(&rq->cfs, p); - /* - * If in_iowait is set, the code below may not trigger any cpufreq - * utilization updates, so do it here explicitly with the IOWAIT flag - * passed. - */ - if (p->in_iowait) - cpufreq_update_util(rq, SCHED_CPUFREQ_IOWAIT); - for_each_sched_entity(se) { if (se->on_rq) break; @@ -9351,10 +9315,6 @@ static bool __update_blocked_others(struct rq *rq, bool *done) unsigned long hw_pressure; bool decayed; - /* - * update_load_avg() can call cpufreq_update_util(). Make sure that RT, - * DL and IRQ signals have been updated before updating CFS. - */ curr_class = rq->curr->sched_class; hw_pressure = arch_scale_hw_pressure(cpu_of(rq)); @@ -12685,6 +12645,7 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued) update_misfit_status(curr, rq); check_update_overutilized_status(task_rq(curr)); + cpufreq_update_util(rq, 0); task_tick_core(rq, curr); } diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 3261b067b67e..fe6d8b0ffa95 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -556,11 +556,8 @@ static void sched_rt_rq_dequeue(struct rt_rq *rt_rq) rt_se = rt_rq->tg->rt_se[cpu]; - if (!rt_se) { + if (!rt_se) dequeue_top_rt_rq(rt_rq, rt_rq->rt_nr_running); - /* Kick cpufreq (see the comment in kernel/sched/sched.h). */ - cpufreq_update_util(rq_of_rt_rq(rt_rq), 0); - } else if (on_rt_rq(rt_se)) dequeue_rt_entity(rt_se, 0); } @@ -1065,9 +1062,6 @@ enqueue_top_rt_rq(struct rt_rq *rt_rq) add_nr_running(rq, rt_rq->rt_nr_running); rt_rq->rt_queued = 1; } - - /* Kick cpufreq (see the comment in kernel/sched/sched.h). */ - cpufreq_update_util(rq, 0); } #if defined CONFIG_SMP diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index cb3792c04eea..86cec2145221 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -632,6 +632,11 @@ struct cfs_rq { unsigned long runnable_avg; } removed; + /* + * Store whether last update_load_avg() has decayed + */ + bool decayed; + #ifdef CONFIG_FAIR_GROUP_SCHED u64 last_update_tg_load_avg; unsigned long tg_load_avg_contrib;