From 44273abc2fea0134de4c7fd9807a7ded59511ae7 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 1 Jan 2026 21:01:16 -0500 Subject: [PATCH] sched_ext: Factor out local_dsq_post_enq() from dispatch_enqueue() [ Upstream commit 530b6637c79e728d58f1d9b66bd4acf4b735b86d ] Factor out local_dsq_post_enq() which performs post-enqueue handling for local DSQs - triggering resched_curr() if SCX_ENQ_PREEMPT is specified or if the current CPU is idle. No functional change. This will be used by the next patch to fix move_local_task_to_local_dsq(). Cc: stable@vger.kernel.org # v6.12+ Reviewed-by: Andrea Righi Reviewed-by: Emil Tsalapatis Signed-off-by: Tejun Heo Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- kernel/sched/ext.c | 34 +++++++++++++++++++--------------- 1 file changed, 19 insertions(+), 15 deletions(-) diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index 614275e4b05ca..c4d841c13225e 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -1676,6 +1676,22 @@ static void dsq_mod_nr(struct scx_dispatch_q *dsq, s32 delta) WRITE_ONCE(dsq->nr, dsq->nr + delta); } +static void local_dsq_post_enq(struct scx_dispatch_q *dsq, struct task_struct *p, + u64 enq_flags) +{ + struct rq *rq = container_of(dsq, struct rq, scx.local_dsq); + bool preempt = false; + + if ((enq_flags & SCX_ENQ_PREEMPT) && p != rq->curr && + rq->curr->sched_class == &ext_sched_class) { + rq->curr->scx.slice = 0; + preempt = true; + } + + if (preempt || sched_class_above(&ext_sched_class, rq->curr->sched_class)) + resched_curr(rq); +} + static void dispatch_enqueue(struct scx_dispatch_q *dsq, struct task_struct *p, u64 enq_flags) { @@ -1773,22 +1789,10 @@ static void dispatch_enqueue(struct scx_dispatch_q *dsq, struct task_struct *p, if (enq_flags & SCX_ENQ_CLEAR_OPSS) atomic_long_set_release(&p->scx.ops_state, SCX_OPSS_NONE); - if (is_local) { - struct rq *rq = container_of(dsq, struct rq, scx.local_dsq); - bool preempt = false; - - if ((enq_flags & SCX_ENQ_PREEMPT) && p != rq->curr && - rq->curr->sched_class == &ext_sched_class) { - rq->curr->scx.slice = 0; - preempt = true; - } - - if (preempt || sched_class_above(&ext_sched_class, - rq->curr->sched_class)) - resched_curr(rq); - } else { + if (is_local) + local_dsq_post_enq(dsq, p, enq_flags); + else raw_spin_unlock(&dsq->lock); - } } static void task_unlink_from_dsq(struct task_struct *p, -- 2.47.3