The following commit has been merged into the sched/core branch of tip: Commit-ID: 25ac227a25ac946e0356772012398cd1710a8bab Gitweb: https://git.kernel.org/tip/25ac227a25ac946e0356772012398cd1710a8bab Author: Morten Rasmussen <morten.rasmussen@xxxxxxx> AuthorDate: Thu, 06 Feb 2020 19:19:57 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitterDate: Tue, 11 Feb 2020 13:04:16 +01:00 sched/fair: Remove wake_cap() Capacity-awareness in the wake-up path previously involved disabling wake_affine in certain scenarios. We have just made select_idle_sibling() capacity-aware, so this isn't needed anymore. Remove wake_cap() entirely. Signed-off-by: Morten Rasmussen <morten.rasmussen@xxxxxxx> [Changelog tweaks] Signed-off-by: Valentin Schneider <valentin.schneider@xxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> [Changelog tweaks] Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Link: https://lkml.kernel.org/r/20200206191957.12325-5-valentin.schneider@xxxxxxx --- kernel/sched/fair.c | 30 +----------------------------- 1 file changed, 1 insertion(+), 29 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 6fb47a2..a7e11b1 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6146,33 +6146,6 @@ static unsigned long cpu_util_without(int cpu, struct task_struct *p) } /* - * Disable WAKE_AFFINE in the case where task @p doesn't fit in the - * capacity of either the waking CPU @cpu or the previous CPU @prev_cpu. - * - * In that case WAKE_AFFINE doesn't make sense and we'll let - * BALANCE_WAKE sort things out. - */ -static int wake_cap(struct task_struct *p, int cpu, int prev_cpu) -{ - long min_cap, max_cap; - - if (!static_branch_unlikely(&sched_asym_cpucapacity)) - return 0; - - min_cap = min(capacity_orig_of(prev_cpu), capacity_orig_of(cpu)); - max_cap = cpu_rq(cpu)->rd->max_cpu_capacity; - - /* Minimum capacity is close to max, no need to abort wake_affine */ - if (max_cap - min_cap < max_cap >> 3) - return 0; - - /* Bring task utilization in sync with prev_cpu */ - sync_entity_load_avg(&p->se); - - return !task_fits_capacity(p, min_cap); -} - -/* * Predicts what cpu_util(@cpu) would return if @p was migrated (and enqueued) * to @dst_cpu. */ @@ -6436,8 +6409,7 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f new_cpu = prev_cpu; } - want_affine = !wake_wide(p) && !wake_cap(p, cpu, prev_cpu) && - cpumask_test_cpu(cpu, p->cpus_ptr); + want_affine = !wake_wide(p) && cpumask_test_cpu(cpu, p->cpus_ptr); } rcu_read_lock();
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