From 1087ad4e3f88c474b8134a482720782922bf3fdf Mon Sep 17 00:00:00 2001 From: Yury Norov Date: Thu, 10 Feb 2022 14:49:06 -0800 Subject: [PATCH] sched: replace cpumask_weight with cpumask_empty where appropriate In some places, kernel/sched code calls cpumask_weight() to check if any bit of a given cpumask is set. We can do it more efficiently with cpumask_empty() because cpumask_empty() stops traversing the cpumask as soon as it finds first set bit, while cpumask_weight() counts all bits unconditionally. Signed-off-by: Yury Norov Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20220210224933.379149-23-yury.norov@gmail.com --- kernel/sched/core.c | 2 +- kernel/sched/topology.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 1d863d7f6ad7..c620aab27acf 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -8708,7 +8708,7 @@ int cpuset_cpumask_can_shrink(const struct cpumask *cur, { int ret = 1; - if (!cpumask_weight(cur)) + if (cpumask_empty(cur)) return ret; ret = dl_cpuset_cpumask_can_shrink(cur, trial); diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index e6cd55951304..1c84b48def20 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -74,7 +74,7 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, break; } - if (!cpumask_weight(sched_group_span(group))) { + if (cpumask_empty(sched_group_span(group))) { printk(KERN_CONT "\n"); printk(KERN_ERR "ERROR: empty group\n"); break;