From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755360AbZCCNrV (ORCPT ); Tue, 3 Mar 2009 08:47:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755011AbZCCNqO (ORCPT ); Tue, 3 Mar 2009 08:46:14 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:59148 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1754817AbZCCNqM (ORCPT ); Tue, 3 Mar 2009 08:46:12 -0500 Message-ID: <49AD3442.5040306@cn.fujitsu.com> Date: Tue, 03 Mar 2009 21:44:34 +0800 From: Lai Jiangshan User-Agent: Thunderbird 2.0.0.6 (Windows/20070728) MIME-Version: 1.0 To: Andrew Morton CC: Pekka Enberg , Christoph Lameter , Nick Piggin , "Paul E. McKenney" , Manfred Spraul , Ingo Molnar , Peter Zijlstra , linux-kernel@vger.kernel.org Subject: [PATCH -mm 4/6] slqb: record slab's start address in slqb_page Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org slqb's slab is coloring, it's will be useful that record the color value or start address in struct slqb_page. This fix adds a field in struct slqb_page to record slab's start address, It will be used by kfree_rcu(). struct slqb_page has a field: struct kmem_cache_list *list; the corresponding field in struct page is: union { struct { unsigned long private; struct address_space *mapping; }; struct kmem_cache *slab; struct page *first_page; }; It's large than 'struct kmem_cache_list *list;' *So we are safe to add a field in struct page.* (This field will not become a burden in future:) struct page is very small, this fix uses the last room of struct page. But if we have to add a more important field in struct slqb_page in future, We can record slab's color value in slqb_page instead of start address. like this: struct { unsigned long flags; atomic_t _count; u16 inuse; /* use u16 instead */ u16 color; /* of unsigned int */ void *a_more_important_field; struct kmem_cache_list *list; void **freelist; union { struct list_head lru; struct rcu_head rcu_head; }; }; Signed-off-by: Lai Jiangshan --- diff --git a/mm/slqb.c b/mm/slqb.c index 48bdf3b..c258ddc 100644 --- a/mm/slqb.c +++ b/mm/slqb.c @@ -41,6 +41,7 @@ struct slqb_page { unsigned long flags; /* mandatory */ atomic_t _count; /* mandatory */ unsigned int inuse; /* Nr of objects */ + void *s_mem; /* start address */ struct kmem_cache_list *list; /* Pointer to list */ void **freelist; /* LIFO freelist */ union { @@ -1010,6 +1011,7 @@ static struct slqb_page *new_slab_page(struct kmem_cache *s, } set_freepointer(s, last, NULL); + page->s_mem = start; page->freelist = start; page->inuse = 0; out: