linux-kernel - [PATCH] sched/deadline: simplify dl_bw_cpus() using cpumask_weight

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Date:   Mon, 22 May 2023 19:56:05 +0800
From:   Miaohe Lin <linmiaohe@...wei.com>
To:     <mingo@...hat.com>, <peterz@...radead.org>,
        <juri.lelli@...hat.com>, <vincent.guittot@...aro.org>
CC:     <dietmar.eggemann@....com>, <rostedt@...dmis.org>,
        <bsegall@...gle.com>, <mgorman@...e.de>, <bristot@...hat.com>,
        <vschneid@...hat.com>, <linux-kernel@...r.kernel.org>,
        <linmiaohe@...wei.com>
Subject: [PATCH] sched/deadline: simplify dl_bw_cpus() using cpumask_weight_and()

cpumask_weight_and() can be used to count of bits both in rd->span and
cpu_active_mask. No functional change intended.

Signed-off-by: Miaohe Lin <linmiaohe@...wei.com>
---
 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 166c3e6eae61..fe983ed7bb12 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -110,20 +110,11 @@ 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)
-- 
2.27.0