diff options
| author | Yuyang Du <[email protected]> | 2015-10-13 09:18:22 +0800 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2015-10-20 10:13:34 +0200 |
| commit | fde7d22e01aa0d252fc5c95fa11f0dac35a4dd59 (patch) | |
| tree | 9e5a21c5052af5f7b695a0203f2dca7bdbddd3ea | |
| parent | 9babcd7929bc8967ae3bb6093f603b93c2f9958f (diff) | |
sched/fair: Fix overly small weight for interactive group entities
Commit:
9d89c257dfb9 ("sched/fair: Rewrite runnable load and utilization average tracking")
led to an overly small weight for interactive group entities. The bad case
can be easily reproduced when a number of CPU hogs compete for the CPUs
at the same time (thanks to Mike). This is largly because the task group's
load average tracking cross CPUs lags behind the real changes.
To fix this we accelerate the group share distribution process by using
the load.weight of the cfs_rq. This may increase the entire group's
share, but we have to do so to protect the (fragile) interactive
tasks, especially from CPU hogs.
Reported-by: Mike Galbraith <[email protected]>
Tested-by: Dietmar Eggemann <[email protected]>
Tested-by: Mike Galbraith <[email protected]>
Signed-off-by: Yuyang Du <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Acked-by: Dietmar Eggemann <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | kernel/sched/fair.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 6e2e3483b1ec..bc62c5096e54 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2363,7 +2363,7 @@ static inline long calc_tg_weight(struct task_group *tg, struct cfs_rq *cfs_rq) */ tg_weight = atomic_long_read(&tg->load_avg); tg_weight -= cfs_rq->tg_load_avg_contrib; - tg_weight += cfs_rq_load_avg(cfs_rq); + tg_weight += cfs_rq->load.weight; return tg_weight; } @@ -2373,7 +2373,7 @@ static long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg) long tg_weight, load, shares; tg_weight = calc_tg_weight(tg, cfs_rq); - load = cfs_rq_load_avg(cfs_rq); + load = cfs_rq->load.weight; shares = (tg->shares * load); if (tg_weight) |