The following commit has been merged into the sched/core branch of tip:
Commit-ID: 3e6efe87cd5ccabf0f1d4e3ef25881ca0fd337e7
Gitweb: https://git.kernel.org/tip/3e6efe87cd5ccabf0f1d4e3ef25881ca0fd337e7
Author: Abel Wu <wuyun.abel@xxxxxxxxxxxxx>
AuthorDate: Wed, 07 Sep 2022 19:19:56 +08:00
Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Wed, 07 Sep 2022 21:53:46 +02:00
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 <wuyun.abel@xxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Josh Don <joshdon@xxxxxxxxxx>
Acked-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220907112000.1854-2-wuyun.abel@xxxxxxxxxxxxx
---
kernel/sched/fair.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index efceb67..9657c7d 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;
}
|