From bdb7c802cc0a7e21f5223dc3ce41b7ac220c576e Mon Sep 17 00:00:00 2001 From: Valentin Schneider Date: Mon, 17 Aug 2020 12:29:59 +0100 Subject: [PATCH] sched/topology: Mark SD_SERIALIZE as SDF_NEEDS_GROUPS There would be no point in preserving a sched_domain with a single group just because it has this flag set. Add it to SD_DEGENERATE_GROUPS_MASK. Signed-off-by: Valentin Schneider Signed-off-by: Ingo Molnar Acked-by: Peter Zijlstra Link: https://lore.kernel.org/r/20200817113003.20802-14-valentin.schneider@arm.com --- include/linux/sched/sd_flags.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/include/linux/sched/sd_flags.h b/include/linux/sched/sd_flags.h index 729510a..b7f4d80 100644 --- a/include/linux/sched/sd_flags.h +++ b/include/linux/sched/sd_flags.h @@ -112,11 +112,12 @@ SD_FLAG(SD_SHARE_PKG_RESOURCES, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) * Only a single load balancing instance * * SHARED_PARENT: Set for all NUMA levels above NODE. Could be set from a - * different level upwards, but it doesn't change that if a domain has this flag - * set, then all of its parents need to have it too (otherwise the serialization - * doesn't make sense). + * different level upwards, but it doesn't change that if a + * domain has this flag set, then all of its parents need to have + * it too (otherwise the serialization doesn't make sense). + * NEEDS_GROUPS: No point in preserving domain if it has a single group. */ -SD_FLAG(SD_SERIALIZE, SDF_SHARED_PARENT) +SD_FLAG(SD_SERIALIZE, SDF_SHARED_PARENT | SDF_NEEDS_GROUPS) /* * Place busy tasks earlier in the domain -- 2.7.4