diff options
| author | Tianchen Ding <dtcccc@linux.alibaba.com> | 2024-03-06 10:21:33 +0800 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2024-04-22 13:01:26 +0200 |
| commit | afae8002b4fd3560c8f5f1567f3c3202c30a70fa (patch) | |
| tree | 0c2bb2420c07352f18b64f7a7ca3fed7f1c81ab7 | |
| parent | 11b1b8bc2b98e21ddf47e08b56c21502c685b2c3 (diff) | |
| download | linux-afae8002b4fd3560c8f5f1567f3c3202c30a70fa.tar.gz | |
sched/eevdf: Fix miscalculation in reweight_entity() when se is not curr
reweight_eevdf() only keeps V unchanged inside itself. When se !=
cfs_rq->curr, it would be dequeued from rb tree first. So that V is
changed and the result is wrong. Pass the original V to reweight_eevdf()
to fix this issue.
Fixes: eab03c23c2a1 ("sched/eevdf: Fix vruntime adjustment on reweight")
Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com>
[peterz: flip if() condition for clarity]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Abel Wu <wuyun.abel@bytedance.com>
Link: https://lkml.kernel.org/r/20240306022133.81008-3-dtcccc@linux.alibaba.com
| -rw-r--r-- | kernel/sched/fair.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 5551ce2af73e7e..6d266917d38d7f 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3676,11 +3676,10 @@ static inline void dequeue_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) { } #endif -static void reweight_eevdf(struct cfs_rq *cfs_rq, struct sched_entity *se, +static void reweight_eevdf(struct sched_entity *se, u64 avruntime, unsigned long weight) { unsigned long old_weight = se->load.weight; - u64 avruntime = avg_vruntime(cfs_rq); s64 vlag, vslice; /* @@ -3787,24 +3786,26 @@ static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, unsigned long weight) { bool curr = cfs_rq->curr == se; + u64 avruntime; if (se->on_rq) { /* commit outstanding execution time */ update_curr(cfs_rq); + avruntime = avg_vruntime(cfs_rq); if (!curr) __dequeue_entity(cfs_rq, se); update_load_sub(&cfs_rq->load, se->load.weight); } dequeue_load_avg(cfs_rq, se); - if (!se->on_rq) { + if (se->on_rq) { + reweight_eevdf(se, avruntime, weight); + } else { /* * Because we keep se->vlag = V - v_i, while: lag_i = w_i*(V - v_i), * we need to scale se->vlag when w_i changes. */ se->vlag = div_s64(se->vlag * se->load.weight, weight); - } else { - reweight_eevdf(cfs_rq, se, weight); } update_load_set(&se->load, weight); |