From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f182.google.com (mail-pd0-f182.google.com [209.85.192.182]) by kanga.kvack.org (Postfix) with ESMTP id 8ACD46B0038 for ; Thu, 21 Aug 2014 04:11:34 -0400 (EDT) Received: by mail-pd0-f182.google.com with SMTP id fp1so13570919pdb.27 for ; Thu, 21 Aug 2014 01:11:34 -0700 (PDT) Received: from lgeamrelo01.lge.com (lgeamrelo01.lge.com. [156.147.1.125]) by mx.google.com with ESMTP id p3si35444564pdg.107.2014.08.21.01.11.32 for ; Thu, 21 Aug 2014 01:11:33 -0700 (PDT) From: Joonsoo Kim Subject: [PATCH 3/3] mm/slab: support slab merge Date: Thu, 21 Aug 2014 17:11:15 +0900 Message-Id: <1408608675-20420-3-git-send-email-iamjoonsoo.kim@lge.com> In-Reply-To: <1408608675-20420-1-git-send-email-iamjoonsoo.kim@lge.com> References: <1408608675-20420-1-git-send-email-iamjoonsoo.kim@lge.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Christoph Lameter , Pekka Enberg , David Rientjes , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Joonsoo Kim Slab merge is good feature to reduce fragmentation. If new creating slab have similar size and property with exsitent slab, this feature reuse it rather than creating new one. As a result, objects are packed into fewer slabs so that fragmentation is reduced. Below is result of my testing. * After boot, sleep 20; cat /proc/meminfo | grep Slab Slab: 25136 kB Slab: 24364 kB We can save 3% memory used by slab. Signed-off-by: Joonsoo Kim --- mm/slab.c | 20 ++++++++++++++++++++ mm/slab.h | 2 +- 2 files changed, 21 insertions(+), 1 deletion(-) diff --git a/mm/slab.c b/mm/slab.c index 09b060e..a1cc1c9 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -2052,6 +2052,26 @@ static int __init_refok setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp) return 0; } +unsigned long kmem_cache_flags(unsigned long object_size, + unsigned long flags, const char *name, + void (*ctor)(void *)) +{ + return flags; +} + +struct kmem_cache * +__kmem_cache_alias(const char *name, size_t size, size_t align, + unsigned long flags, void (*ctor)(void *)) +{ + struct kmem_cache *cachep; + + cachep = find_mergeable(size, align, flags, name, ctor); + if (cachep) + cachep->refcount++; + + return cachep; +} + /** * __kmem_cache_create - Create a cache. * @cachep: cache management descriptor diff --git a/mm/slab.h b/mm/slab.h index 7c6e1ed..13845d0 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -89,7 +89,7 @@ struct mem_cgroup; int slab_unmergeable(struct kmem_cache *s); struct kmem_cache *find_mergeable(size_t size, size_t align, unsigned long flags, const char *name, void (*ctor)(void *)); -#ifdef CONFIG_SLUB +#ifndef CONFIG_SLOB struct kmem_cache * __kmem_cache_alias(const char *name, size_t size, size_t align, unsigned long flags, void (*ctor)(void *)); -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org