gfs2: fix to detect failure of register_shrinker

register_shrinker can fail after commit 1d3d4437eae1 ("vmscan: per-node
deferred work"), we should detect the failure of it, otherwise we may
fail to register shrinker after gfs2 module was been inited successfully.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>

2 files changed, 10 insertions, 2 deletions

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index c8e2e7f62051..14cbf60167a7 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1781,7 +1781,13 @@ int __init gfs2_glock_init(void)
                 return -ENOMEM;
         }
 
-        register_shrinker(&glock_shrinker);
+        ret = register_shrinker(&glock_shrinker);
+        if (ret) {
+                destroy_workqueue(gfs2_delete_workqueue);
+                destroy_workqueue(glock_workqueue);
+                rhashtable_destroy(&gl_hash_table);
+                return ret;
+        }
 
         return 0;
 }
diff --git a/fs/gfs2/main.c b/fs/gfs2/main.c
index 74fd0139e6c2..67d1fc4668f7 100644
--- a/fs/gfs2/main.c
+++ b/fs/gfs2/main.c
@@ -145,7 +145,9 @@ static int __init init_gfs2_fs(void)
         if (!gfs2_qadata_cachep)
                 goto fail;
 
-        register_shrinker(&gfs2_qd_shrinker);
+        error = register_shrinker(&gfs2_qd_shrinker);
+        if (error)
+                goto fail;
 
         error = register_filesystem(&gfs2_fs_type);
         if (error)