A domain with the SD_ASYM_CPUCAPACITY flag set indicate that sched_groups at this level and below do not include cpus of all capacities available (e.g. group containing little-only or big-only cpus in big.LITTLE systems). It is therefore necessary to put in more effort in finding an appropriate cpu at task wake-up by enabling balancing at wake-up (SD_BALANCE_WAKE) on all lower (child) levels.
cc: Ingo Molnar <[email protected]> cc: Peter Zijlstra <[email protected]> Signed-off-by: Morten Rasmussen <[email protected]> --- kernel/sched/core.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index ec3f7aef321f..a0a74b2d9f41 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6414,6 +6414,13 @@ sd_init(struct sched_domain_topology_level *tl, * Convert topological properties into behaviour. */ + if (sd->flags & SD_ASYM_CPUCAPACITY) { + struct sched_domain *t = sd; + + for_each_lower_domain(t) + t->flags |= SD_BALANCE_WAKE; + } + if (sd->flags & SD_SHARE_CPUCAPACITY) { sd->flags |= SD_PREFER_SIBLING; sd->imbalance_pct = 110; -- 1.9.1
