On Tue, May 02, 2023 at 08:01:41AM +0800, zhouzhouyi@xxxxxxxxx wrote:
> From: Zhouyi Zhou <zhouzhouyi@xxxxxxxxx>
>
> In kfree_rcu_test, kfree_scale_shutdown will be detected as hung task
> if kfree_loops is too big. Replace wait_event with wait_event_idle
> to avoid false positive.
>
> Tested in the PPC VM of Open Source Lab of Oregon State University.
>
> Suggested-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
> Signed-off-by: Zhouyi Zhou <zhouzhouyi@xxxxxxxxx>
Good catch, thank you!
However, this commit beat you to it:
ef1ef3d47677 ("rcuscale: Move shutdown from wait_event() to wait_event_idle()")
Thanx, Paul
> ---
> kernel/rcu/rcuscale.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/rcu/rcuscale.c b/kernel/rcu/rcuscale.c
> index 91fb5905a008..d99c586939d1 100644
> --- a/kernel/rcu/rcuscale.c
> +++ b/kernel/rcu/rcuscale.c
> @@ -771,7 +771,7 @@ kfree_scale_cleanup(void)
> static int
> kfree_scale_shutdown(void *arg)
> {
> - wait_event(shutdown_wq,
> + wait_event_idle(shutdown_wq,
> atomic_read(&n_kfree_scale_thread_ended) >= kfree_nrealthreads);
>
> smp_mb(); /* Wake before output. */
> --
> 2.34.1
>
