From: Lauro Ramos Venancio <lvenanci@redhat.com>
Date: Thu, 20 Apr 2017 19:51:40 +0000 (-0300)
Subject: sched/topology: Optimize build_group_mask()
X-Git-Tag: C0P2-H0.0--20200415~8147
X-Git-Url: https://git.somdevices.com/?a=commitdiff_plain;h=3e165b2322c6a7e50031cb91ef95ee6cb4e1d163;p=linux.git

sched/topology: Optimize build_group_mask()

commit f32d782e31bf079f600dcec126ed117b0577e85c upstream.

The group mask is always used in intersection with the group CPUs. So,
when building the group mask, we don't have to care about CPUs that are
not part of the group.

Signed-off-by: Lauro Ramos Venancio <lvenanci@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: lwang@redhat.com
Cc: riel@redhat.com
Link: http://lkml.kernel.org/r/1492717903-5195-2-git-send-email-lvenanci@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 19f84d98d24c..326be9da4ee4 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6113,12 +6113,12 @@ enum s_alloc {
  */
 static void build_group_mask(struct sched_domain *sd, struct sched_group *sg)
 {
-	const struct cpumask *span = sched_domain_span(sd);
+	const struct cpumask *sg_span = sched_group_cpus(sg);
 	struct sd_data *sdd = sd->private;
 	struct sched_domain *sibling;
 	int i;
 
-	for_each_cpu(i, span) {
+	for_each_cpu(i, sg_span) {
 		sibling = *per_cpu_ptr(sdd->sd, i);
 		if (!cpumask_test_cpu(i, sched_domain_span(sibling)))
 			continue;