diff options
| author | Aubrey Li <aubrey.li@intel.com> | 2020-03-26 06:42:29 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2020-04-08 11:35:20 +0200 |
| commit | 111688ca1c4a43a7e482f5401f82c46326b8ed49 (patch) | |
| tree | 9ff221c39692293560d0b9def0cef07c081abd98 /kernel | |
| parent | sched/fair: Fix race between runtime distribution and assignment (diff) | |
| download | linux-111688ca1c4a43a7e482f5401f82c46326b8ed49.tar.xz linux-111688ca1c4a43a7e482f5401f82c46326b8ed49.zip | |
sched/fair: Fix negative imbalance in imbalance calculation
A negative imbalance value was observed after imbalance calculation,
this happens when the local sched group type is group_fully_busy,
and the average load of local group is greater than the selected
busiest group. Fix this problem by comparing the average load of the
local and busiest group before imbalance calculation formula.
Suggested-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/1585201349-70192-1-git-send-email-aubrey.li@intel.com
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/fair.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 95cbd9e7958d..02f323b85b6d 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -9036,6 +9036,14 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s sds->avg_load = (sds->total_load * SCHED_CAPACITY_SCALE) / sds->total_capacity; + /* + * If the local group is more loaded than the selected + * busiest group don't try to pull any tasks. + */ + if (local->avg_load >= busiest->avg_load) { + env->imbalance = 0; + return; + } } /* |