summaryrefslogtreecommitdiff
path: root/kernel/sched_fair.c
diff options
context:
space:
mode:
authorIngo Molnar <mingo@elte.hu>2007-08-12 18:08:19 +0200
committerIngo Molnar <mingo@elte.hu>2007-08-12 18:08:19 +0200
commit5d2b3d3695a841231b65b5536a70dc29961c5611 (patch)
treeeac6ed4b85734714b308f7f8b70ace62efb631ac /kernel/sched_fair.c
parent6707de00fdec3e3225192fe3dcd21323a8936b1f (diff)
downloadlwn-5d2b3d3695a841231b65b5536a70dc29961c5611.tar.gz
lwn-5d2b3d3695a841231b65b5536a70dc29961c5611.zip
sched: fix sleeper bonus
Peter Ziljstra noticed that the sleeper bonus deduction code was not properly rate-limited: a task that scheduled more frequently would get a disproportionately large deduction. So limit the deduction to delta_exec. Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched_fair.c')
-rw-r--r--kernel/sched_fair.c12
1 files changed, 6 insertions, 6 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index c5af38948a1e..fedbb51bba96 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -75,7 +75,7 @@ enum {
unsigned int sysctl_sched_features __read_mostly =
SCHED_FEAT_FAIR_SLEEPERS *1 |
- SCHED_FEAT_SLEEPER_AVG *1 |
+ SCHED_FEAT_SLEEPER_AVG *0 |
SCHED_FEAT_SLEEPER_LOAD_AVG *1 |
SCHED_FEAT_PRECISE_CPU_LOAD *1 |
SCHED_FEAT_START_DEBIT *1 |
@@ -304,11 +304,9 @@ __update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr)
delta_mine = calc_delta_mine(delta_exec, curr->load.weight, lw);
if (cfs_rq->sleeper_bonus > sysctl_sched_granularity) {
- delta = calc_delta_mine(cfs_rq->sleeper_bonus,
- curr->load.weight, lw);
- if (unlikely(delta > cfs_rq->sleeper_bonus))
- delta = cfs_rq->sleeper_bonus;
-
+ delta = min(cfs_rq->sleeper_bonus, (u64)delta_exec);
+ delta = calc_delta_mine(delta, curr->load.weight, lw);
+ delta = min((u64)delta, cfs_rq->sleeper_bonus);
cfs_rq->sleeper_bonus -= delta;
delta_mine -= delta;
}
@@ -521,6 +519,8 @@ static void __enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
* Track the amount of bonus we've given to sleepers:
*/
cfs_rq->sleeper_bonus += delta_fair;
+ if (unlikely(cfs_rq->sleeper_bonus > sysctl_sched_runtime_limit))
+ cfs_rq->sleeper_bonus = sysctl_sched_runtime_limit;
schedstat_add(cfs_rq, wait_runtime, se->wait_runtime);
}