[PATCH v1 2/2] NFSD: Change the filecache laundrette workqueue again

[cel@kernel.org]

From: Chuck Lever <chuck.lever@oracle.com>

Youzhong Yang <youzhong@gmail.com> noticed the workqueue subsystem
complaining about how long the filecache laundrette was running.
This resulted in switching from using the system_wq for the
laundrette to system_unbound_wq (see commit 4b84551a35e3 ("nfsd: use
system_unbound_wq for nfsd_file_gc_worker()").

However, I've seen the laundrette running for multiple milliseconds
on some workloads, delaying other work. For the purpose of
scheduling fairness, perhaps a better choice would be to process
filecache disposal queues on the system_long_wq instead.

Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/filecache.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index a1cdba42c4fa..91a535c2dede 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -112,7 +112,7 @@ static void
 nfsd_file_schedule_laundrette(void)
 {
 	if (test_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags))
-		queue_delayed_work(system_unbound_wq, &nfsd_filecache_laundrette,
+		queue_delayed_work(system_long_wq, &nfsd_filecache_laundrette,
 				   NFSD_LAUNDRETTE_DELAY);
 }
 
-- 
2.47.0