kernel/sched/ext/ext.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-)
Remote consumption now reaches the !dsq branch with holding_cpu set,
just like direct dispatch. Also, the dsq-present branch races with
unlink_dsq_and_switch_rq_lock(), not dispatch_to_local_dsq().
Update both comments to describe the current transfer paths. No
functional change.
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Usama Arif <usama.arif@linux.dev>
---
kernel/sched/ext/ext.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/kernel/sched/ext/ext.c b/kernel/sched/ext/ext.c
index 0135ff6824b03..f95d1cf8d3d1c 100644
--- a/kernel/sched/ext/ext.c
+++ b/kernel/sched/ext/ext.c
@@ -1832,10 +1832,9 @@ void scx_dispatch_dequeue(struct rq *rq, struct task_struct *p)
list_del_init(&p->scx.dsq_list.node);
/*
- * When dispatching directly from the BPF scheduler to a local
- * DSQ, the task isn't associated with any DSQ but
- * @p->scx.holding_cpu may be set under the protection of
- * %SCX_OPSS_DISPATCHING.
+ * When moving a task to a local DSQ through either direct dispatch
+ * or remote consumption, the task isn't associated with any DSQ but
+ * @p->scx.holding_cpu may be set.
*/
if (p->scx.holding_cpu >= 0)
p->scx.holding_cpu = -1;
@@ -1855,9 +1854,9 @@ void scx_dispatch_dequeue(struct rq *rq, struct task_struct *p)
scx_task_unlink_from_dsq(p, dsq);
} else {
/*
- * We're racing against dispatch_to_local_dsq() which already
- * removed @p from @dsq and set @p->scx.holding_cpu. Clear the
- * holding_cpu which tells dispatch_to_local_dsq() that it lost
+ * We're racing against unlink_dsq_and_switch_rq_lock(), which
+ * already removed @p from @dsq and set @p->scx.holding_cpu. Clear
+ * holding_cpu to tell unlink_dsq_and_switch_rq_lock() that it lost
* the race.
*/
WARN_ON_ONCE(!list_empty(&p->scx.dsq_list.node));
--
2.53.0-Meta
Hello, Usama. On Wed, Sep 23, 2026 at 02:34:18PM -0700, Usama Arif wrote: > /* > - * When dispatching directly from the BPF scheduler to a local > - * DSQ, the task isn't associated with any DSQ but > - * @p->scx.holding_cpu may be set under the protection of > - * %SCX_OPSS_DISPATCHING. > + * When moving a task to a local DSQ through either direct dispatch > + * or remote consumption, the task isn't associated with any DSQ but > + * @p->scx.holding_cpu may be set. > */ dispatch_to_local_dsq() sets holding_cpu for ops.dispatch() inserts too, not just direct dispatches. Can you name dispatch_to_local_dsq() instead, here and in the description? Clearing holding_cpu here is also how dispatch_to_local_dsq() learns that it lost to a dequeue. The old comment on the other branch described that, but for the wrong branch. Can you add a sentence about it here? Can you also rewrap both comments at 80 columns? A few lines go past it. Thanks. -- tejun
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