Commit 053d27fb authored by Tejun Heo's avatar Tejun Heo
Browse files

sched_ext: Change find_global_dsq() to take CPU number instead of task 



Change find_global_dsq() to take a CPU number directly instead of a task
pointer. This prepares for callers where the CPU is available but the task is
not.

No functional changes.

v2: Rename tcpu to cpu in find_global_dsq() (Emil Tsalapatis).

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Reviewed-by: default avatarEmil Tsalapatis <emil@etsalapatis.com>
Reviewed-by: default avatarDaniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: default avatarAndrea Righi <arighi@nvidia.com>
parent 363cd075

kernel/sched/ext.c

+15 −17
Original line number Diff line number Diff line
@@ -341,10 +341,9 @@ static bool scx_is_descendant(struct scx_sched *sch, struct scx_sched *ancestor) 
	for ((pos) = scx_next_descendant_pre(NULL, (root)); (pos);		\

	     (pos) = scx_next_descendant_pre((pos), (root)))



static struct scx_dispatch_q *find_global_dsq(struct scx_sched *sch,

					      struct task_struct *p)

static struct scx_dispatch_q *find_global_dsq(struct scx_sched *sch, s32 cpu)

{

	return &sch->pnode[cpu_to_node(task_cpu(p))]->global_dsq;

	return &sch->pnode[cpu_to_node(cpu)]->global_dsq;

}



static struct scx_dispatch_q *find_user_dsq(struct scx_sched *sch, u64 dsq_id)
@@ -1266,7 +1265,7 @@ static void dispatch_enqueue(struct scx_sched *sch, struct rq *rq, 
			scx_error(sch, "attempting to dispatch to a destroyed dsq");

			/* fall back to the global dsq */

			raw_spin_unlock(&dsq->lock);

			dsq = find_global_dsq(sch, p);

			dsq = find_global_dsq(sch, task_cpu(p));

			raw_spin_lock(&dsq->lock);

		}

	}
@@ -1474,7 +1473,7 @@ static void dispatch_dequeue_locked(struct task_struct *p, 


static struct scx_dispatch_q *find_dsq_for_dispatch(struct scx_sched *sch,

						    struct rq *rq, u64 dsq_id,

						    struct task_struct *p)

						    s32 tcpu)

{

	struct scx_dispatch_q *dsq;
@@ -1485,20 +1484,19 @@ static struct scx_dispatch_q *find_dsq_for_dispatch(struct scx_sched *sch, 
		s32 cpu = dsq_id & SCX_DSQ_LOCAL_CPU_MASK;



		if (!ops_cpu_valid(sch, cpu, "in SCX_DSQ_LOCAL_ON dispatch verdict"))

			return find_global_dsq(sch, p);

			return find_global_dsq(sch, tcpu);



		return &cpu_rq(cpu)->scx.local_dsq;

	}



	if (dsq_id == SCX_DSQ_GLOBAL)

		dsq = find_global_dsq(sch, p);

		dsq = find_global_dsq(sch, tcpu);

	else

		dsq = find_user_dsq(sch, dsq_id);



	if (unlikely(!dsq)) {

		scx_error(sch, "non-existent DSQ 0x%llx for %s[%d]",

			  dsq_id, p->comm, p->pid);

		return find_global_dsq(sch, p);

		scx_error(sch, "non-existent DSQ 0x%llx", dsq_id);

		return find_global_dsq(sch, tcpu);

	}



	return dsq;
@@ -1540,7 +1538,7 @@ static void direct_dispatch(struct scx_sched *sch, struct task_struct *p, 
{

	struct rq *rq = task_rq(p);

	struct scx_dispatch_q *dsq =

		find_dsq_for_dispatch(sch, rq, p->scx.ddsp_dsq_id, p);

		find_dsq_for_dispatch(sch, rq, p->scx.ddsp_dsq_id, task_cpu(p));



	touch_core_sched_dispatch(rq, p);
@@ -1683,7 +1681,7 @@ static void do_enqueue_task(struct rq *rq, struct task_struct *p, u64 enq_flags, 
	dsq = &rq->scx.local_dsq;

	goto enqueue;

global:

	dsq = find_global_dsq(sch, p);

	dsq = find_global_dsq(sch, task_cpu(p));

	goto enqueue;

bypass:

	dsq = bypass_enq_target_dsq(sch, task_cpu(p));
@@ -2139,7 +2137,7 @@ static struct rq *move_task_between_dsqs(struct scx_sched *sch, 
		dst_rq = container_of(dst_dsq, struct rq, scx.local_dsq);

		if (src_rq != dst_rq &&

		    unlikely(!task_can_run_on_remote_rq(sch, p, dst_rq, true))) {

			dst_dsq = find_global_dsq(sch, p);

			dst_dsq = find_global_dsq(sch, task_cpu(p));

			dst_rq = src_rq;

		}

	} else {
@@ -2268,7 +2266,7 @@ static void dispatch_to_local_dsq(struct scx_sched *sch, struct rq *rq, 


	if (src_rq != dst_rq &&

	    unlikely(!task_can_run_on_remote_rq(sch, p, dst_rq, true))) {

		dispatch_enqueue(sch, rq, find_global_dsq(sch, p), p,

		dispatch_enqueue(sch, rq, find_global_dsq(sch, task_cpu(p)), p,

				 enq_flags | SCX_ENQ_CLEAR_OPSS);

		return;

	}
@@ -2406,7 +2404,7 @@ static void finish_dispatch(struct scx_sched *sch, struct rq *rq, 


	BUG_ON(!(p->scx.flags & SCX_TASK_QUEUED));



	dsq = find_dsq_for_dispatch(sch, this_rq(), dsq_id, p);

	dsq = find_dsq_for_dispatch(sch, this_rq(), dsq_id, task_cpu(p));



	if (dsq->id == SCX_DSQ_LOCAL)

		dispatch_to_local_dsq(sch, rq, dsq, p, enq_flags);
@@ -2646,7 +2644,7 @@ static void process_ddsp_deferred_locals(struct rq *rq) 


		list_del_init(&p->scx.dsq_list.node);



		dsq = find_dsq_for_dispatch(sch, rq, p->scx.ddsp_dsq_id, p);

		dsq = find_dsq_for_dispatch(sch, rq, p->scx.ddsp_dsq_id, task_cpu(p));

		if (!WARN_ON_ONCE(dsq->id != SCX_DSQ_LOCAL))

			dispatch_to_local_dsq(sch, rq, dsq, p,

					      p->scx.ddsp_enq_flags);
@@ -7409,7 +7407,7 @@ static bool scx_dsq_move(struct bpf_iter_scx_dsq_kern *kit, 
	}



	/* @p is still on $src_dsq and stable, determine the destination */

	dst_dsq = find_dsq_for_dispatch(sch, this_rq, dsq_id, p);

	dst_dsq = find_dsq_for_dispatch(sch, this_rq, dsq_id, task_cpu(p));



	/*

	 * Apply vtime and slice updates before moving so that the new time is