[PATCH 23/49] clocksource: replace cpumask_weight with cpumask_empty in clocksource.c

From: Yury Norov
Date: Thu Feb 10 2022 - 18:42:43 EST


clocksource_verify_percpu() 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 <yury.norov@xxxxxxxxx>
---
kernel/time/clocksource.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 95d7ca35bdf2..cee5da1e54c4 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -343,7 +343,7 @@ void clocksource_verify_percpu(struct clocksource *cs)
cpus_read_lock();
preempt_disable();
clocksource_verify_choose_cpus();
- if (cpumask_weight(&cpus_chosen) == 0) {
+ if (cpumask_empty(&cpus_chosen)) {
preempt_enable();
cpus_read_unlock();
pr_warn("Not enough CPUs to check clocksource '%s'.\n", cs->name);
--
2.32.0