From 3fdb9ebcec10a91e7825b95840c5a627dabcbca7 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 10 Oct 2024 11:41:44 -1000 Subject: [PATCH] sched_ext: Start schedulers with consistent p->scx.slice values The disable path caps p->scx.slice to SCX_SLICE_DFL. As the field is already being ignored at this stage during disable, the only effect this has is that when the next BPF scheduler is loaded, it won't see unreasonable left-over slices. Ultimately, this shouldn't matter but it's better to start in a known state. Drop p->scx.slice capping from the disable path and instead reset it to SCX_SLICE_DFL in the enable path. Signed-off-by: Tejun Heo Acked-by: David Vernet --- kernel/sched/ext.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index 2cb304b37014..4e56230e6e4a 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -4473,7 +4473,6 @@ static void scx_ops_disable_workfn(struct kthread_work *work) sched_deq_and_put_task(p, DEQUEUE_SAVE | DEQUEUE_MOVE, &ctx); - p->scx.slice = min_t(u64, p->scx.slice, SCX_SLICE_DFL); __setscheduler_prio(p, p->prio); check_class_changing(task_rq(p), p, old_class); @@ -5190,6 +5189,7 @@ static int scx_ops_enable(struct sched_ext_ops *ops, struct bpf_link *link) sched_deq_and_put_task(p, DEQUEUE_SAVE | DEQUEUE_MOVE, &ctx); + p->scx.slice = SCX_SLICE_DFL; __setscheduler_prio(p, p->prio); check_class_changing(task_rq(p), p, old_class);