[PATCH 2/2] sched/deadline: Use cpumask_weight_and in dl_bw_cpus
From: Shrikanth Hegde
Date: Tue Oct 14 2025 - 06:04:10 EST
- cpumask_subset(a,b) -> cpumask_weight(a) should be same as
cpumask_weight_and(a,b)
- for_each_cpu_and(a,b) to count cpus could be replaced by
cpumask_weight_and(a,b)
No Functional Change. It could save a few cycles since cpumask_weight_and
would be more efficient. Plus one less stack variable.
Signed-off-by: Shrikanth Hegde <sshegde@xxxxxxxxxxxxx>
---
kernel/sched/deadline.c | 11 +----------
1 file changed, 1 insertion(+), 10 deletions(-)
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 8b7c4ee41fd8..a18f64b2e47c 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -125,20 +125,11 @@ static inline struct dl_bw *dl_bw_of(int i)
static inline int dl_bw_cpus(int i)
{
struct root_domain *rd = cpu_rq(i)->rd;
- int cpus;
RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
"sched RCU must be held");
- if (cpumask_subset(rd->span, cpu_active_mask))
- return cpumask_weight(rd->span);
-
- cpus = 0;
-
- for_each_cpu_and(i, rd->span, cpu_active_mask)
- cpus++;
-
- return cpus;
+ return cpumask_weight_and(rd->span, cpu_active_mask);
}
static inline unsigned long __dl_bw_capacity(const struct cpumask *mask)
--
2.47.3