Commit 5c605cd3 authored by Changwoo Min's avatar Changwoo Min Committed by Tejun Heo
Browse files

sched_ext: Add an event, SCX_EV_BYPASS_DISPATCH 



Add a core event, SCX_EV_BYPASS_DISPATCH, which represents how many
tasks have been dispatched in the bypass mode.

__scx_add_event() is used since the caller holds an rq lock or
p->pi_lock, so the preemption has already been disabled.

Signed-off-by: default avatarChangwoo Min <changwoo@igalia.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 4f7a38c7

kernel/sched/ext.c

+17 −2
Original line number Diff line number Diff line
@@ -1468,6 +1468,11 @@ struct scx_event_stats { 
	 */

	u64		SCX_EV_ENQ_SKIP_EXITING;



	/*

	 * The number of tasks dispatched in the bypassing mode.

	 */

	u64		SCX_EV_BYPASS_DISPATCH;



	/*

	 * The number of times the bypassing mode has been activated.

	 */
@@ -2071,8 +2076,10 @@ static void do_enqueue_task(struct rq *rq, struct task_struct *p, u64 enq_flags, 
	if (!scx_rq_online(rq))

		goto local;



	if (scx_rq_bypassing(rq))

	if (scx_rq_bypassing(rq)) {

		__scx_add_event(SCX_EV_BYPASS_DISPATCH, 1);

		goto global;

	}



	if (p->scx.ddsp_dsq_id != SCX_DSQ_INVALID)

		goto direct;
@@ -3253,6 +3260,8 @@ bool scx_prio_less(const struct task_struct *a, const struct task_struct *b, 


static int select_task_rq_scx(struct task_struct *p, int prev_cpu, int wake_flags)

{

	bool rq_bypass;



	/*

	 * sched_exec() calls with %WF_EXEC when @p is about to exec(2) as it

	 * can be a good migration opportunity with low cache and memory
@@ -3266,7 +3275,8 @@ static int select_task_rq_scx(struct task_struct *p, int prev_cpu, int wake_flag 
	if (unlikely(wake_flags & WF_EXEC))

		return prev_cpu;



	if (SCX_HAS_OP(select_cpu) && !scx_rq_bypassing(task_rq(p))) {

	rq_bypass = scx_rq_bypassing(task_rq(p));

	if (SCX_HAS_OP(select_cpu) && !rq_bypass) {

		s32 cpu;

		struct task_struct **ddsp_taskp;
@@ -3292,6 +3302,9 @@ static int select_task_rq_scx(struct task_struct *p, int prev_cpu, int wake_flag 
			p->scx.slice = SCX_SLICE_DFL;

			p->scx.ddsp_dsq_id = SCX_DSQ_LOCAL;

		}



		if (rq_bypass)

			__scx_add_event(SCX_EV_BYPASS_DISPATCH, 1);

		return cpu;

	}

}
@@ -5000,6 +5013,7 @@ static void scx_dump_state(struct scx_exit_info *ei, size_t dump_len) 
	scx_dump_event(s, &events, SCX_EV_DISPATCH_LOCAL_DSQ_OFFLINE);

	scx_dump_event(s, &events, SCX_EV_DISPATCH_KEEP_LAST);

	scx_dump_event(s, &events, SCX_EV_ENQ_SKIP_EXITING);

	scx_dump_event(s, &events, SCX_EV_BYPASS_DISPATCH);

	scx_dump_event(s, &events, SCX_EV_BYPASS_ACTIVATE);



	if (seq_buf_has_overflowed(&s) && dump_len >= sizeof(trunc_marker))
@@ -7138,6 +7152,7 @@ __bpf_kfunc void scx_bpf_events(struct scx_event_stats *events, 
		scx_agg_event(&e_sys, e_cpu, SCX_EV_DISPATCH_LOCAL_DSQ_OFFLINE);

		scx_agg_event(&e_sys, e_cpu, SCX_EV_DISPATCH_KEEP_LAST);

		scx_agg_event(&e_sys, e_cpu, SCX_EV_ENQ_SKIP_EXITING);

		scx_agg_event(&e_sys, e_cpu, SCX_EV_BYPASS_DISPATCH);

		scx_agg_event(&e_sys, e_cpu, SCX_EV_BYPASS_ACTIVATE);

	}