Add a core event, SCX_EV_ENQ_SKIP_EXITING, which represents how many
times a task is enqueued to a local DSQ when exiting if
SCX_OPS_ENQ_EXITING is not set.
__scx_add_event() is used since the caller holds an rq lock,
so the preemption has already been disabled.
Signed-off-by: Changwoo Min <changwoo@igalia.com>
---
kernel/sched/ext.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c
index cbb3d059072f..c72ba405a1d3 100644
--- a/kernel/sched/ext.c
+++ b/kernel/sched/ext.c
@@ -1461,6 +1461,12 @@ struct scx_event_stats {
* continued to run because there were no other tasks on the CPU.
*/
u64 SCX_EV_DISPATCH_KEEP_LAST;
+
+ /*
+ * If SCX_OPS_ENQ_EXITING is not set, the number of times that a task
+ * is dispatched to a local DSQ when exiting.
+ */
+ u64 SCX_EV_ENQ_SKIP_EXITING;
};
/*
@@ -2068,8 +2074,10 @@ static void do_enqueue_task(struct rq *rq, struct task_struct *p, u64 enq_flags,
/* see %SCX_OPS_ENQ_EXITING */
if (!static_branch_unlikely(&scx_ops_enq_exiting) &&
- unlikely(p->flags & PF_EXITING))
+ unlikely(p->flags & PF_EXITING)) {
+ __scx_add_event(SCX_EV_ENQ_SKIP_EXITING, 1);
goto local;
+ }
if (!SCX_HAS_OP(enqueue))
goto global;
@@ -4985,6 +4993,7 @@ static void scx_dump_state(struct scx_exit_info *ei, size_t dump_len)
scx_dump_event(s, &events, SCX_EV_SELECT_CPU_FALLBACK);
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);
if (seq_buf_has_overflowed(&s) && dump_len >= sizeof(trunc_marker))
memcpy(ei->dump + dump_len - sizeof(trunc_marker),
@@ -7121,6 +7130,7 @@ __bpf_kfunc void scx_bpf_events(struct scx_event_stats *events,
scx_agg_event(&e_sys, e_cpu, SCX_EV_SELECT_CPU_FALLBACK);
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);
}
/*
--
2.48.1