mm, slub: use kmem_cache_debug_flags() in deactivate_slab()

Commit 9cf7a1118365 ("mm/slub: make add_full() condition more explicit")
replaced an unnecessarily generic kmem_cache_debug(s) check with an
explicit check of SLAB_STORE_USER and #ifdef CONFIG_SLUB_DEBUG.

We can achieve the same specific check with the recently added
kmem_cache_debug_flags() which removes the #ifdef and restores the
no-branch-overhead benefit of static key check when slub debugging is not
enabled.

Link: https://lkml.kernel.org/r/3ef24214-38c7-1238-8296-88caf7f48ab6@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Abel Wu <wuyun.wu@huawei.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Liu Xiang <liu.xiang6@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/slub.c b/mm/slub.c
index 2098a54..79afc8a 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2245,8 +2245,7 @@ redo:
                }
        } else {
                m = M_FULL;
-#ifdef CONFIG_SLUB_DEBUG
-               if ((s->flags & SLAB_STORE_USER) && !lock) {
+               if (kmem_cache_debug_flags(s, SLAB_STORE_USER) && !lock) {
                        lock = 1;
                        /*
                         * This also ensures that the scanning of full
@@ -2255,7 +2254,6 @@ redo:
                         */
                        spin_lock(&n->list_lock);
                }
-#endif
        }
 
        if (l != m) {