From 3e6efe87cd5ccabf0f1d4e3ef25881ca0fd337e7 Mon Sep 17 00:00:00 2001 From: Abel Wu Date: Wed, 7 Sep 2022 19:19:56 +0800 Subject: sched/fair: Remove redundant check in select_idle_smt() If two cpus share LLC cache, then the two cores they belong to are also in the same LLC domain. Signed-off-by: Abel Wu Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Josh Don Acked-by: Mel Gorman Link: https://lore.kernel.org/r/20220907112000.1854-2-wuyun.abel@bytedance.com --- kernel/sched/fair.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) (limited to 'kernel/sched') diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index efceb670e755..9657c7de5f57 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6350,14 +6350,11 @@ static int select_idle_core(struct task_struct *p, int core, struct cpumask *cpu /* * Scan the local SMT mask for idle CPUs. */ -static int select_idle_smt(struct task_struct *p, struct sched_domain *sd, int target) +static int select_idle_smt(struct task_struct *p, int target) { int cpu; - for_each_cpu(cpu, cpu_smt_mask(target)) { - if (!cpumask_test_cpu(cpu, p->cpus_ptr) || - !cpumask_test_cpu(cpu, sched_domain_span(sd))) - continue; + for_each_cpu_and(cpu, cpu_smt_mask(target), p->cpus_ptr) { if (available_idle_cpu(cpu) || sched_idle_cpu(cpu)) return cpu; } @@ -6381,7 +6378,7 @@ static inline int select_idle_core(struct task_struct *p, int core, struct cpuma return __select_idle_cpu(core, p); } -static inline int select_idle_smt(struct task_struct *p, struct sched_domain *sd, int target) +static inline int select_idle_smt(struct task_struct *p, int target) { return -1; } @@ -6615,7 +6612,7 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) has_idle_core = test_idle_cores(target, false); if (!has_idle_core && cpus_share_cache(prev, target)) { - i = select_idle_smt(p, sd, prev); + i = select_idle_smt(p, prev); if ((unsigned int)i < nr_cpumask_bits) return i; } -- cgit