From: Yury Norov <yury.norov@xxxxxxxxx> Subject: mm/slub.c: avoid double string traverse in kmem_cache_flags() If ',' is not found, kmem_cache_flags() calls strlen() to find the end of line. We can do it in a single pass using strchrnul(). Link: http://lkml.kernel.org/r/20190501053111.7950-1-ynorov@xxxxxxxxxxx Signed-off-by: Yury Norov <ynorov@xxxxxxxxxxx> Acked-by: Aaron Tomlin <atomlin@xxxxxxxxxx> Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: Pekka Enberg <penberg@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/slub.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/mm/slub.c~mm-slub-avoid-double-string-traverse-in-kmem_cache_flags +++ a/mm/slub.c @@ -1313,9 +1313,7 @@ slab_flags_t kmem_cache_flags(unsigned i char *end, *glob; size_t cmplen; - end = strchr(iter, ','); - if (!end) - end = iter + strlen(iter); + end = strchrnul(iter, ','); glob = strnchr(iter, end - iter, '*'); if (glob) _
