Re: [PATCH] dm-bufio: fix sched in atomic context

[Sheng Yong]

On 7/15/25 01:17, Mikulas Patocka wrote:

On Thu, 10 Jul 2025, Sheng Yong wrote:

From: Sheng Yong <shengyo...@xiaomi.com>

[..]

diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
index ec84ba5e93e5..caf6ae9a8b52 100644
--- a/drivers/md/dm-bufio.c
+++ b/drivers/md/dm-bufio.c
@@ -2742,7 +2742,9 @@ static unsigned long __evict_a_few(unsigned long 
nr_buffers)
                __make_buffer_clean(b);
                __free_buffer_wake(b);

+ dm_bufio_unlock(c);

                cond_resched();
+               dm_bufio_lock(c);
        }

dm_bufio_unlock(c);

--
2.43.0

Hi

I accepted this patch. I changed it to:

-               cond_resched();
+               if (need_resched()) {
+                       dm_bufio_unlock(c);
+                       cond_resched();
+                       dm_bufio_lock(c);
+               }
         }

         dm_bufio_unlock(c);

so that we are not hammering on the dm bufio lock when scheduling is not
needed.

Hi, Mikulas,

Thank you for the update. It looks good to me.

thanks,
Yong

Mikulas