[PATCH] nilfs2: Add missing set_freezable() for freezable kthread

From: Ryusuke Konishi
Date: Tue Dec 19 2023 - 04:09:47 EST


From: Kevin Hao <haokexin@xxxxxxxxx>

The kernel thread function nilfs_segctor_thread() invokes
the try_to_freeze() in its loop. But all the kernel threads are
non-freezable by default. So if we want to make a kernel thread to be
freezable, we have to invoke set_freezable() explicitly.

Signed-off-by: Kevin Hao <haokexin@xxxxxxxxx>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
---
Andrew, please add this to the queue for the next merge window (if
it's still ok). This fixes an issue where the log writer thread was
not calling try_to_freeze() as intended when starting suspend or
hibernation.

I haven't run into any problems with or without this change in various
suspend/hibernation tests so far, so I haven't added a Cc tag to the
stable team.

If any suspend failures are reported due to the lack of this setup,
I will separately request the stable team to backport this.

Thanks,
Ryusuke Konishi

fs/nilfs2/segment.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index 52995838f2de..2590a0860eab 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -2588,6 +2588,7 @@ static int nilfs_segctor_thread(void *arg)
"segctord starting. Construction interval = %lu seconds, CP frequency < %lu seconds",
sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);

+ set_freezable();
spin_lock(&sci->sc_state_lock);
loop:
for (;;) {
--
2.34.1