sched/topology: Optimize build_group_mask()

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>

diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index 81c82031ed9575a06c46ef837bd7e95ec78ebd94..5a4d9aeda2588b414e07443f798826d10ee84b27 100644 (file)
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -506,12 +506,12 @@ 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;