diff options
Diffstat (limited to 'kernel/sched/topology.c')
| -rw-r--r-- | kernel/sched/topology.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 21efacf547d4..09563c1d1d5b 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -495,6 +495,9 @@ enum s_alloc { /* * Build an iteration mask that can exclude certain CPUs from the upwards * domain traversal. + * + * Only CPUs that can arrive at this group should be considered to continue + * balancing. */ static void build_group_mask(struct sched_domain *sd, struct sched_group *sg) { @@ -505,11 +508,24 @@ static void build_group_mask(struct sched_domain *sd, struct sched_group *sg) for_each_cpu(i, sg_span) { sibling = *per_cpu_ptr(sdd->sd, i); - if (!cpumask_test_cpu(i, sched_domain_span(sibling))) + + /* + * Can happen in the asymmetric case, where these siblings are + * unused. The mask will not be empty because those CPUs that + * do have the top domain _should_ span the domain. + */ + if (!sibling->child) + continue; + + /* If we would not end up here, we can't continue from here */ + if (!cpumask_equal(sg_span, sched_domain_span(sibling->child))) continue; cpumask_set_cpu(i, sched_group_mask(sg)); } + + /* We must not have empty masks here */ + WARN_ON_ONCE(cpumask_empty(sched_group_mask(sg))); } /* |