Commit-ID:  743cb1ff191f00fee653212bdbcee1e56086d6ce
Gitweb:     http://git.kernel.org/tip/743cb1ff191f00fee653212bdbcee1e56086d6ce
Author:     Peter Zijlstra <[email protected]>
AuthorDate: Tue, 29 Jul 2014 17:00:21 +0200
Committer:  Ingo Molnar <[email protected]>
CommitDate: Tue, 12 Aug 2014 12:48:18 +0200

sched/fair: Make calculate_imbalance() independent

Rik noticed that calculate_imbalance() relies on
update_sd_pick_busiest() to guarantee that busiest->sum_nr_running >
busiest->group_capacity_factor.

Break this implicit assumption (with the intent of not providing it
anymore) by having calculat_imbalance() verify it and not rely on
others.

Reported-by: Rik van Riel <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Acked-by: Vincent Guittot <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
 kernel/sched/fair.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index bfa3c86..e9477e6 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6248,7 +6248,7 @@ static inline void calculate_imbalance(struct lb_env 
*env, struct sd_lb_stats *s
                return fix_small_imbalance(env, sds);
        }
 
-       if (!busiest->group_imb) {
+       if (busiest->sum_nr_running > busiest->group_capacity_factor) {
                /*
                 * Don't want to pull so many tasks that a group would go idle.
                 * Except of course for the group_imb case, since then we might
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to