[PATCH] sched_ext: Allow dequeue_task_scx to fail

From: Yipeng Zou
Date: Mon Aug 19 2024 - 22:38:26 EST


Since dequeue_task() allowed to fail, there is a compile error:

kernel/sched/ext.c:3630:19: error: initialization of ‘bool (*)(struct rq*, struct task_struct *, int)’ {aka ‘_Bool (*)(struct rq *, struct task_struct *, int)’} from incompatible pointer type ‘void (*)(struct rq*, struct task_struct *, int)’
3630 | .dequeue_task = dequeue_task_scx,
| ^~~~~~~~~~~~~~~~

Allow dequeue_task_scx to fail too.

Fixes: 863ccdbb918a ("sched: Allow sched_class::dequeue_task() to fail")
Signed-off-by: Yipeng Zou <zouyipeng@xxxxxxxxxx>
---
kernel/sched/ext.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c
index 571a7ea0b5cb..b9bf9ee5ed01 100644
--- a/kernel/sched/ext.c
+++ b/kernel/sched/ext.c
@@ -2033,11 +2033,11 @@ static void ops_dequeue(struct task_struct *p, u64 deq_flags)
}
}

-static void dequeue_task_scx(struct rq *rq, struct task_struct *p, int deq_flags)
+static bool dequeue_task_scx(struct rq *rq, struct task_struct *p, int deq_flags)
{
if (!(p->scx.flags & SCX_TASK_QUEUED)) {
WARN_ON_ONCE(task_runnable(p));
- return;
+ return true;
}

ops_dequeue(p, deq_flags);
@@ -2072,6 +2072,7 @@ static void dequeue_task_scx(struct rq *rq, struct task_struct *p, int deq_flags
sub_nr_running(rq, 1);

dispatch_dequeue(rq, p);
+ return true;
}

static void yield_task_scx(struct rq *rq)
--
2.34.1