[tip: irq/core] genirq/affinity: Replace cpumask_weight() with cpumask_empty() where appropriate

[tip-bot2 for Yury Norov]

The following commit has been merged into the irq/core branch of tip:

Commit-ID:     911488de0565f1d53bd36174d20917ebc4b44c0e
Gitweb:        https://git.kernel.org/tip/911488de0565f1d53bd36174d20917ebc4b44c0e
Author:        Yury Norov <yury.norov@xxxxxxxxx>
AuthorDate:    Thu, 10 Feb 2022 14:49:05 -08:00
Committer:     Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Sun, 10 Apr 2022 22:20:28 +02:00

genirq/affinity: Replace cpumask_weight() with cpumask_empty() where appropriate

__irq_build_affinity_masks() calls cpumask_weight() to check if any bit of
a given cpumask is set.

This can be done 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@xxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220210224933.379149-22-yury.norov@xxxxxxxxx

---
 kernel/irq/affinity.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c
index f7ff891..18740fa 100644
--- a/kernel/irq/affinity.c
+++ b/kernel/irq/affinity.c
@@ -258,7 +258,7 @@ static int __irq_build_affinity_masks(unsigned int startvec,
 	nodemask_t nodemsk = NODE_MASK_NONE;
 	struct node_vectors *node_vectors;
 
-	if (!cpumask_weight(cpu_mask))
+	if (cpumask_empty(cpu_mask))
 		return 0;
 
 	nodes = get_nodes_in_cpumask(node_to_cpumask, cpu_mask, &nodemsk);