Commit 3546119f authored by Tejun Heo's avatar Tejun Heo
Browse files

sched_ext: Refactor do_enqueue_task() local and global DSQ paths 



The local and global DSQ enqueue paths in do_enqueue_task() share the same
slice refill logic. Factor out the common code into a shared enqueue label.
This makes adding new enqueue cases easier. No functional changes.

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 bfd3749d

kernel/sched/ext.c

+12 −9
Original line number Diff line number Diff line
@@ -1279,6 +1279,7 @@ static void do_enqueue_task(struct rq *rq, struct task_struct *p, u64 enq_flags, 
{

	struct scx_sched *sch = scx_root;

	struct task_struct **ddsp_taskp;

	struct scx_dispatch_q *dsq;

	unsigned long qseq;



	WARN_ON_ONCE(!(p->scx.flags & SCX_TASK_QUEUED));
@@ -1346,8 +1347,17 @@ static void do_enqueue_task(struct rq *rq, struct task_struct *p, u64 enq_flags, 
direct:

	direct_dispatch(sch, p, enq_flags);

	return;



local_norefill:

	dispatch_enqueue(sch, &rq->scx.local_dsq, p, enq_flags);

	return;

local:

	dsq = &rq->scx.local_dsq;

	goto enqueue;

global:

	dsq = find_global_dsq(sch, p);

	goto enqueue;



enqueue:

	/*

	 * For task-ordering, slice refill must be treated as implying the end

	 * of the current slice. Otherwise, the longer @p stays on the CPU, the
@@ -1355,14 +1365,7 @@ static void do_enqueue_task(struct rq *rq, struct task_struct *p, u64 enq_flags, 
	 */

	touch_core_sched(rq, p);

	refill_task_slice_dfl(sch, p);

local_norefill:

	dispatch_enqueue(sch, &rq->scx.local_dsq, p, enq_flags);

	return;



global:

	touch_core_sched(rq, p);	/* see the comment in local: */

	refill_task_slice_dfl(sch, p);

	dispatch_enqueue(sch, find_global_dsq(sch, p), p, enq_flags);

	dispatch_enqueue(sch, dsq, p, enq_flags);

}



static bool task_runnable(const struct task_struct *p)