Commit 530b6637 authored by Tejun Heo's avatar Tejun Heo
Browse files

sched_ext: Factor out local_dsq_post_enq() from dispatch_enqueue() 



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: default avatarAndrea Righi <arighi@nvidia.com>
Reviewed-by: default avatarEmil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 9f769637

kernel/sched/ext.c

+19 −15
Original line number Diff line number Diff line
@@ -982,6 +982,22 @@ static void refill_task_slice_dfl(struct scx_sched *sch, struct task_struct *p) 
	__scx_add_event(sch, SCX_EV_REFILL_SLICE_DFL, 1);

}



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_sched *sch, struct scx_dispatch_q *dsq,

			     struct task_struct *p, u64 enq_flags)

{
@@ -1093,23 +1109,11 @@ static void dispatch_enqueue(struct scx_sched *sch, struct scx_dispatch_q *dsq, 
	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,

				 struct scx_dispatch_q *dsq)