Re: [PATCH 5.15 00/23] 5.15.160-rc1 review

NeilBrown
2024-05-28T23:42:33Z

On Wed, 29 May 2024, NeilBrown wrote:
>
> We probably just need to add "| TASK_FREEZABLE" in one or two places.
> I'll post a patch for testing in a little while.

There is no TASK_FREEZABLE before v6.1.
This isn't due to a missed backport. It is simply because of differences
in the freezer in older kernels.

Please test this patch.

Thanks,
NeilBrown

From 416bd6ae9a598e64931d34b76aa58f39b11841cd Mon Sep 17 00:00:00 2001
From: NeilBrown <neilb@suse.de>
Date: Wed, 29 May 2024 09:38:22 +1000
Subject: [PATCH] sunrpc: exclude from freezer when waiting for requests:

Prior to v6.1, the freezer will only wake a kernel thread from an
uninterruptible sleep. Since we changed svc_get_next_xprt() to use and
IDLE sleep the freezer cannot wake it. we need to tell the freezer to
ignore it instead.

Fixes: 9b8a8e5e8129 ("nfsd: don't allow nfsd threads to be signalled.")
Signed-off-by: NeilBrown <neilb@suse.de>
---
net/sunrpc/svc_xprt.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index b19592673eef..12e9293bd12b 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -764,10 +764,12 @@ static struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout)
clear_bit(RQ_BUSY, &rqstp->rq_flags);
smp_mb__after_atomic();

+ freezer_do_not_count();
if (likely(rqst_should_sleep(rqstp)))
time_left = schedule_timeout(timeout);
else
__set_current_state(TASK_RUNNING);
+ freezer_count();

try_to_freeze();

--
2.44.0