[PATCH 1/8] mm: vmscan: move shrinker_debugfs_remove() before synchronize_srcu()

From: Qi Zheng
Date: Wed May 31 2023 - 05:58:56 EST


From: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>

The debugfs_remove_recursive() will wait for debugfs_file_put()
to return, so there is no need to put it after synchronize_srcu()
to wait for the rcu read-side critical section to exit.

Just move it before synchronize_srcu(), which is also convenient
to put the heavy synchronize_srcu() in the delayed work later.

Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>
---
mm/vmscan.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index eeca83e28c9b..a773e97e152e 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -818,11 +818,11 @@ void unregister_shrinker(struct shrinker *shrinker)
debugfs_entry = shrinker_debugfs_detach(shrinker, &debugfs_id);
mutex_unlock(&shrinker_mutex);

+ shrinker_debugfs_remove(debugfs_entry, debugfs_id);
+
atomic_inc(&shrinker_srcu_generation);
synchronize_srcu(&shrinker_srcu);

- shrinker_debugfs_remove(debugfs_entry, debugfs_id);
-
kfree(shrinker->nr_deferred);
shrinker->nr_deferred = NULL;
}
--
2.30.2