[PATCH 3/3] vhost: Fix livepatch timeouts in vhost_worker()

From: Josh Poimboeuf
Date: Thu Feb 09 2023 - 14:18:35 EST


Livepatch timeouts were reported due to busy vhost_worker() kthreads.
Now that cond_resched() can do livepatch task switching, use
cond_resched() in vhost_worker(). That's the better way to
conditionally call schedule() anyway.

Reported-by: Seth Forshee (DigitalOcean) <sforshee@xxxxxxxxxxxxxxxx>
Link: https://lkml.kernel.org/lkml/20230120-vhost-klp-switching-v1-0-7c2b65519c43@xxxxxxxxxx
Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
---
drivers/vhost/vhost.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index cbe72bfd2f1f..424c0c939f57 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -363,8 +363,7 @@ static int vhost_worker(void *data)
kcov_remote_start_common(dev->kcov_handle);
work->fn(work);
kcov_remote_stop();
- if (need_resched())
- schedule();
+ cond_resched();
}
}
kthread_unuse_mm(dev->mm);
--
2.39.0