From 9ba7f37e5b39654e657df83c266c24ee7bbc2296 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 29 Apr 2025 08:40:11 -1000 Subject: [PATCH] sched_ext: Clean up SCX_EXIT_NONE handling in scx_disable_workfn() With the global states and disable machinery moved into scx_sched, scx_disable_workfn() can only be scheduled and run for the specific scheduler instance. This makes it impossible for scx_disable_workfn() to see SCX_EXIT_NONE. Turn that condition into WARN_ON_ONCE(). Signed-off-by: Tejun Heo Reviewed-by: Andrea Righi Acked-by: Changwoo Min --- kernel/sched/ext.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index a21390c9e9772..66d21c7cdff7d 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -4752,13 +4752,9 @@ static void scx_disable_workfn(struct kthread_work *work) kind = atomic_read(&sch->exit_kind); while (true) { - /* - * NONE indicates that a new scx_ops has been registered since - * disable was scheduled - don't kill the new ops. DONE - * indicates that the ops has already been disabled. - */ - if (kind == SCX_EXIT_NONE || kind == SCX_EXIT_DONE) + if (kind == SCX_EXIT_DONE) /* already disabled? */ return; + WARN_ON_ONCE(kind == SCX_EXIT_NONE); if (atomic_try_cmpxchg(&sch->exit_kind, &kind, SCX_EXIT_DONE)) break; } -- 2.47.3