diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2017-05-12 14:18:10 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-09-29 19:35:17 +0200 |
| commit | 9a2dd585b2c431ec1e5d46a9d9568291c7a534cc (patch) | |
| tree | 987633c0ac6fa9ce7c9f278157d9621f6f1c0fbb /kernel/sched | |
| parent | f207934fb79d1af1de1a62b09d56a3a1914172c4 (diff) | |
sched/fair: Implement more accurate async detach
The problem with the overestimate is that it will subtract too big a
value from the load_sum, thereby pushing it down further than it ought
to go. Since runnable_load_avg is not subject to a similar 'force',
this results in the occasional 'runnable_load > load' situation.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/sched')
| -rw-r--r-- | kernel/sched/fair.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 954b332cd899..67c39642a512 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3574,6 +3574,7 @@ update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) if (cfs_rq->removed.nr) { unsigned long r; + u32 divider = LOAD_AVG_MAX - 1024 + sa->period_contrib; raw_spin_lock(&cfs_rq->removed.lock); swap(cfs_rq->removed.util_avg, removed_util); @@ -3582,17 +3583,13 @@ update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) cfs_rq->removed.nr = 0; raw_spin_unlock(&cfs_rq->removed.lock); - /* - * The LOAD_AVG_MAX for _sum is a slight over-estimate, - * which is safe due to sub_positive() clipping at 0. - */ r = removed_load; sub_positive(&sa->load_avg, r); - sub_positive(&sa->load_sum, r * LOAD_AVG_MAX); + sub_positive(&sa->load_sum, r * divider); r = removed_util; sub_positive(&sa->util_avg, r); - sub_positive(&sa->util_sum, r * LOAD_AVG_MAX); + sub_positive(&sa->util_sum, r * divider); add_tg_cfs_propagate(cfs_rq, -(long)removed_runnable_sum); |