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 19f84d98d24ccd05332b687aef71b68f5d6fd989..326be9da4ee45aba3ffe560fc1a8a4bc1ca463a1 100644 (file)
--- 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;