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From:   Yury Norov <yury.norov@gmail.com>
To:     Yury Norov <yury.norov@gmail.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Peter Zijlstra <peterz@infradead.org>,
        David Laight <David.Laight@aculab.com>,
        Joe Perches <joe@perches.com>, Dennis Zhou <dennis@kernel.org>,
        Emil Renner Berthing <kernel@esmil.dk>,
        Nicholas Piggin <npiggin@gmail.com>,
        Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>,
        Alexey Klimov <aklimov@redhat.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: [PATCH 25/54] mm/vmstat: replace cpumask_weight with cpumask_empty where appropriate
Date:   Sun, 23 Jan 2022 10:38:56 -0800
Message-Id: <20220123183925.1052919-26-yury.norov@gmail.com>
In-Reply-To: <20220123183925.1052919-1-yury.norov@gmail.com>
References: <20220123183925.1052919-1-yury.norov@gmail.com>
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mm/vmstat.c code 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@gmail.com>
---
 mm/vmstat.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/vmstat.c b/mm/vmstat.c
index 4057372745d0..f56f11e3eef5 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -2035,7 +2035,7 @@ static void __init init_cpu_node_state(void)
 	int node;
 
 	for_each_online_node(node) {
-		if (cpumask_weight(cpumask_of_node(node)) > 0)
+		if (!cpumask_empty(cpumask_of_node(node)))
 			node_set_state(node, N_CPU);
 	}
 }
@@ -2062,7 +2062,7 @@ static int vmstat_cpu_dead(unsigned int cpu)
 
 	refresh_zone_stat_thresholds();
 	node_cpus = cpumask_of_node(node);
-	if (cpumask_weight(node_cpus) > 0)
+	if (!cpumask_empty(node_cpus))
 		return 0;
 
 	node_clear_state(node, N_CPU);
-- 
2.30.2