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 a760c9e0353e6c0012dab3659eb756df7e747d96..de691daea7090bc2794c21db37cf62fbc8d194b8 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5863,12 +5863,12 @@ 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;