If there is only a single NUMA node in the system, the only NUMA topology
level that will be generated will be NODE (identity distance), which
doesn't have SD_SERIALIZE.
This means we don't need this special case in sd_parent_degenerate(), as
having the NODE level "naturally" covers it. Thus, remove it.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/20200817113003.20802-10-valentin.schneider@arm.com
return 0;
/* Flags needing groups don't count if only 1 group in parent */
- if (parent->groups == parent->groups->next) {
+ if (parent->groups == parent->groups->next)
pflags &= ~(SD_DEGENERATE_GROUPS_MASK | SD_PREFER_SIBLING);
- if (nr_node_ids == 1)
- pflags &= ~SD_SERIALIZE;
- }
+
if (~cflags & pflags)
return 0;