bcache: check return value of register_shrinker

mlyle · axboe · commit 6c4ca1e36cdc · 2017-11-24T16:23:01.000-07:00
register_shrinker is now __must_check, so check it to kill a warning.
Caller of bch_btree_cache_alloc in super.c appropriately checks return
value so this is fully plumbed through.

This V2 fixes checkpatch warnings and improves the commit description,
as I was too hasty getting the previous version out.

Signed-off-by: Michael Lyle &lt;mlyle@lyle.org&gt;
Reviewed-by: Vojtech Pavlik &lt;vojtech@suse.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
@@ -807,7 +807,10 @@ int bch_btree_cache_alloc(struct cache_set *c)
 	c->shrink.scan_objects = bch_mca_scan;
 	c->shrink.seeks = 4;
 	c->shrink.batch = c->btree_pages * 2;
-	register_shrinker(&c->shrink);
+
+	if (register_shrinker(&c->shrink))
+		pr_warn("bcache: %s: could not register shrinker",
+				__func__);
 
 	return 0;
 }
