linux-kernel - [PATCH 36/49] arch/ia64: replace cpumask_weight with cpumask_weight

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Date:   Thu, 10 Feb 2022 14:49:20 -0800
From:   Yury Norov <yury.norov@...il.com>
To:     Yury Norov <yury.norov@...il.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Michał Mirosław <mirq-linux@...e.qmqm.pl>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Peter Zijlstra <peterz@...radead.org>,
        David Laight <David.Laight@...lab.com>,
        Joe Perches <joe@...ches.com>, Dennis Zhou <dennis@...nel.org>,
        Emil Renner Berthing <kernel@...il.dk>,
        Nicholas Piggin <npiggin@...il.com>,
        Matti Vaittinen <matti.vaittinen@...rohmeurope.com>,
        Alexey Klimov <aklimov@...hat.com>,
        linux-kernel@...r.kernel.org, linux-ia64@...r.kernel.org
Subject: [PATCH 36/49] arch/ia64: replace cpumask_weight with cpumask_weight_eq in mm/tlb.c

__flush_tlb_range() code 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 (or can't be) met.

Signed-off-by: Yury Norov <yury.norov@...il.com>
---
 arch/ia64/mm/tlb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/ia64/mm/tlb.c b/arch/ia64/mm/tlb.c
index 135b5135cace..a5bce13ab047 100644
--- a/arch/ia64/mm/tlb.c
+++ b/arch/ia64/mm/tlb.c
@@ -332,7 +332,7 @@ __flush_tlb_range (struct vm_area_struct *vma, unsigned long start,
 
 	preempt_disable();
 #ifdef CONFIG_SMP
-	if (mm != current->active_mm || cpumask_weight(mm_cpumask(mm)) != 1) {
+	if (mm != current->active_mm || !cpumask_weight_eq(mm_cpumask(mm), 1)) {
 		ia64_global_tlb_purge(mm, start, end, nbits);
 		preempt_enable();
 		return;
-- 
2.32.0