[Cluster-devel] [PATCH] gfs2: Don't sleep during glock hash walk

[Andreas Gruenbacher]

In flush_delete_work, instead of flushing each individual pending
delayed work item, cancel and re-queue them for immediate execution.
The waiting isn't needed here because we're already waiting for all
queued work items to complete in gfs2_flush_delete_work.  This makes the
code more efficient, but more importantly, it avoids sleeping during a
rhashtable walk, inside rcu_read_lock().

Signed-off-by: Andreas Gruenbacher <agruenba at redhat.com>
---
 fs/gfs2/glock.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 2299dcc417ea..8545024a1401 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1899,7 +1899,10 @@ bool gfs2_delete_work_queued(const struct gfs2_glock *gl)
 
 static void flush_delete_work(struct gfs2_glock *gl)
 {
-	flush_delayed_work(&gl->gl_delete);
+	if (cancel_delayed_work(&gl->gl_delete)) {
+		queue_delayed_work(gfs2_delete_workqueue,
+				   &gl->gl_delete, 0);
+	}
 	gfs2_glock_queue_work(gl, 0);
 }
 
-- 
2.26.2