Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753866Ab0DMXkU (ORCPT ); Tue, 13 Apr 2010 19:40:20 -0400 Received: from mail-iw0-f197.google.com ([209.85.223.197]:55768 "EHLO mail-iw0-f197.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753678Ab0DMXkS convert rfc822-to-8bit (ORCPT ); Tue, 13 Apr 2010 19:40:18 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=P4E5njt7kT6I4/ZXww2u7puqKYou04JuBRsWz81wsxkyJyKxQa82k3OWnOz2nj10Bu PSEH4p8/vQd3u3nSyQiKVKIBHh6Tnr1bjym/E4tjcHlU0Ex7Hb0tOd1vyAt1+QL2z156 nxq5leLm/0nN1v8DCild/+701bj34cFNX7Gt4= MIME-Version: 1.0 In-Reply-To: References: <9918f566ab0259356cded31fd1dd80da6cae0c2b.1271171877.git.minchan.kim@gmail.com> <8b348d9cc1ea4960488b193b7e8378876918c0d4.1271171877.git.minchan.kim@gmail.com> Date: Wed, 14 Apr 2010 08:40:16 +0900 Message-ID: Subject: Re: [PATCH 3/6] change alloc function in alloc_slab_page From: Minchan Kim To: David Rientjes Cc: Andrew Morton , Mel Gorman , KAMEZAWA Hiroyuki , Bob Liu , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Christoph Lameter , Pekka Enberg Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1890 Lines: 55 On Wed, Apr 14, 2010 at 6:37 AM, David Rientjes wrote: > On Wed, 14 Apr 2010, Minchan Kim wrote: > >> alloc_slab_page never calls alloc_pages_node with -1. >> It means node's validity check is unnecessary. >> So we can use alloc_pages_exact_node instead of alloc_pages_node. >> It could avoid comparison and branch as 6484eb3e2a81807722 tried. >> >> Cc: Christoph Lameter >> Signed-off-by: Minchan Kim >> --- >>  mm/slub.c |    2 +- >>  1 files changed, 1 insertions(+), 1 deletions(-) >> >> diff --git a/mm/slub.c b/mm/slub.c >> index b364844..9984165 100644 >> --- a/mm/slub.c >> +++ b/mm/slub.c >> @@ -1084,7 +1084,7 @@ static inline struct page *alloc_slab_page(gfp_t flags, int node, >>       if (node == -1) >>               return alloc_pages(flags, order); >>       else >> -             return alloc_pages_node(node, flags, order); >> +             return alloc_pages_exact_node(node, flags, order); >>  } >> >>  static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) > > Slub changes need to go through its maintainer, Pekka Enberg > . Thanks, David. It was by mistake. Pekka. This changlog is bad. I will change it with following as when I send v2. "alloc_slab_page always checks nid == -1, so alloc_page_node can't be called with -1. It means node's validity check in alloc_pages_node is unnecessary. So we can use alloc_pages_exact_node instead of alloc_pages_node. It could avoid comparison and branch as 6484eb3e2a81807722 tried." Thanks. -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/