lkml.org 
[lkml]   [2014]   [Feb]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 1/9] slab: add unlikely macro to help compiler
Date
slab_should_failslab() is called on every allocation, so to optimize it
is reasonable. We normally don't allocate from kmem_cache. It is just
used when new kmem_cache is created, so it's very rare case. Therefore,
add unlikely macro to help compiler optimization.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>

diff --git a/mm/slab.c b/mm/slab.c
index 8347d80..5906f8f 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3009,7 +3009,7 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep,

static bool slab_should_failslab(struct kmem_cache *cachep, gfp_t flags)
{
- if (cachep == kmem_cache)
+ if (unlikely(cachep == kmem_cache))
return false;

return should_failslab(cachep->object_size, flags, cachep->flags);
--
1.7.9.5


\
 
 \ /
  Last update: 2014-02-14 08:41    [W:0.228 / U:0.200 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site