linux-kernel - [PATCH] cgroup/cpuset: drop useless cpumask_empty() in compute_effective_exclusive

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Message-ID: <20250508193207.388041-1-yury.norov@gmail.com>
Date: Thu,  8 May 2025 15:32:06 -0400
From: Yury Norov <yury.norov@...il.com>
To: Waiman Long <longman@...hat.com>,
	Tejun Heo <tj@...nel.org>,
	Johannes Weiner <hannes@...xchg.org>,
	Michal Koutný <mkoutny@...e.com>,
	cgroups@...r.kernel.org,
	linux-kernel@...r.kernel.org
Cc: Yury Norov <yury.norov@...il.com>
Subject: [PATCH] cgroup/cpuset: drop useless cpumask_empty() in compute_effective_exclusive_cpumask()

Empty cpumasks can't intersect with any others. Therefore, testing for
non-emptyness is useless.

Signed-off-by: Yury Norov <yury.norov@...il.com>
---
 kernel/cgroup/cpuset.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 306b60430091..df308072f268 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1388,14 +1388,12 @@ static int compute_effective_exclusive_cpumask(struct cpuset *cs,
 		if (sibling == cs)
 			continue;
 
-		if (!cpumask_empty(sibling->exclusive_cpus) &&
-		    cpumask_intersects(xcpus, sibling->exclusive_cpus)) {
+		if (cpumask_intersects(xcpus, sibling->exclusive_cpus)) {
 			cpumask_andnot(xcpus, xcpus, sibling->exclusive_cpus);
 			retval++;
 			continue;
 		}
-		if (!cpumask_empty(sibling->effective_xcpus) &&
-		    cpumask_intersects(xcpus, sibling->effective_xcpus)) {
+		if (cpumask_intersects(xcpus, sibling->effective_xcpus)) {
 			cpumask_andnot(xcpus, xcpus, sibling->effective_xcpus);
 			retval++;
 		}
-- 
2.43.0