diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2025-11-19 18:26:59 +0100 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2025-11-20 12:14:54 +0100 |
| commit | 79c11fb3da8581a2f222b290ce62a153ab1108fc (patch) | |
| tree | 3d2bda823bf87244b6c189822da17b51d9adc4f6 /kernel/sched/core.c | |
| parent | 437cb3ded25038d5280d21de489ce78c745118d5 (diff) | |
sched/mmcid: Use cpumask_weighted_or()
Use cpumask_weighted_or() instead of cpumask_or() and cpumask_weight() on
the result, which walks the same bitmap twice. Results in 10-20% less
cycles, which reduces the runqueue lock hold time.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Link: https://patch.msgid.link/20251119172549.511736272@linutronix.de
Diffstat (limited to 'kernel/sched/core.c')
| -rw-r--r-- | kernel/sched/core.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 2ea77e72f7c6..f6bbfa1f5c15 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -10377,6 +10377,7 @@ void call_trace_sched_update_nr_running(struct rq *rq, int count) static inline void mm_update_cpus_allowed(struct mm_struct *mm, const struct cpumask *affmsk) { struct cpumask *mm_allowed; + unsigned int weight; if (!mm) return; @@ -10387,8 +10388,8 @@ static inline void mm_update_cpus_allowed(struct mm_struct *mm, const struct cpu */ guard(raw_spinlock)(&mm->mm_cid.lock); mm_allowed = mm_cpus_allowed(mm); - cpumask_or(mm_allowed, mm_allowed, affmsk); - WRITE_ONCE(mm->mm_cid.nr_cpus_allowed, cpumask_weight(mm_allowed)); + weight = cpumask_weighted_or(mm_allowed, mm_allowed, affmsk); + WRITE_ONCE(mm->mm_cid.nr_cpus_allowed, weight); } void sched_mm_cid_exit_signals(struct task_struct *t) |