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Subject[PATCH 40/54] arch/s390: replace cpumask_weight with cpumask_weight_eq where appropriate
Date
cfset_all_start() calls cpumask_weight() to compare the weight of cpumask
with a given number. We can do it more efficiently with
cpumask_weight_{eq, ...} because conditional cpumask_weight may stop
traversing the cpumask earlier, as soon as condition is met.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
arch/s390/kernel/perf_cpum_cf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/s390/kernel/perf_cpum_cf.c b/arch/s390/kernel/perf_cpum_cf.c
index ee8707abdb6a..4d217f7f5ccf 100644
--- a/arch/s390/kernel/perf_cpum_cf.c
+++ b/arch/s390/kernel/perf_cpum_cf.c
@@ -975,7 +975,7 @@ static int cfset_all_start(struct cfset_request *req)
return -ENOMEM;
cpumask_and(mask, &req->mask, cpu_online_mask);
on_each_cpu_mask(mask, cfset_ioctl_on, &p, 1);
- if (atomic_read(&p.cpus_ack) != cpumask_weight(mask)) {
+ if (!cpumask_weight_eq(mask, atomic_read(&p.cpus_ack))) {
on_each_cpu_mask(mask, cfset_ioctl_off, &p, 1);
rc = -EIO;
debug_sprintf_event(cf_dbg, 4, "%s CPUs missing", __func__);
--
2.30.2
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