From 221d7da66cd3435b28a0404f62168d25f57aca4e Mon Sep 17 00:00:00 2001 From: Yangtao Li <tiny.windzz@gmail.com> Date: Fri, 28 Dec 2018 00:33:01 -0800 Subject: [PATCH] mm, slab: remove unnecessary unlikely() WARN_ON() already contains an unlikely(), so it's not necessary to use unlikely. Also change WARN_ON() back to WARN_ON_ONCE() to avoid potentially spamming dmesg with user-triggerable large allocations. [akpm@linux-foundation.org: s/WARN_ON/WARN_ON_ONCE/, per Vlastimil] Link: http://lkml.kernel.org/r/20181104125028.3572-1-tiny.windzz@gmail.com Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- mm/slab_common.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/mm/slab_common.c b/mm/slab_common.c index bc24100682b0..70b0cc85db67 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -1029,10 +1029,8 @@ struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags) index = size_index[size_index_elem(size)]; } else { - if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) { - WARN_ON(1); + if (WARN_ON_ONCE(size > KMALLOC_MAX_CACHE_SIZE)) return NULL; - } index = fls(size - 1); } -- GitLab