From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756603AbZDUJIl (ORCPT ); Tue, 21 Apr 2009 05:08:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754391AbZDUJIb (ORCPT ); Tue, 21 Apr 2009 05:08:31 -0400 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:59115 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753182AbZDUJIa (ORCPT ); Tue, 21 Apr 2009 05:08:30 -0400 From: KOSAKI Motohiro To: Mel Gorman Subject: Re: [PATCH 12/25] Remove a branch by assuming __GFP_HIGH == ALLOC_HIGH Cc: kosaki.motohiro@jp.fujitsu.com, Linux Memory Management List , Christoph Lameter , Nick Piggin , Linux Kernel Mailing List , Lin Ming , Zhang Yanmin , Peter Zijlstra , Pekka Enberg , Andrew Morton In-Reply-To: <1240266011-11140-13-git-send-email-mel@csn.ul.ie> References: <1240266011-11140-1-git-send-email-mel@csn.ul.ie> <1240266011-11140-13-git-send-email-mel@csn.ul.ie> Message-Id: <20090421180757.F145.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.50 [ja] Date: Tue, 21 Apr 2009 18:08:23 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > Allocations that specify __GFP_HIGH get the ALLOC_HIGH flag. If these > flags are equal to each other, we can eliminate a branch. > > [akpm@linux-foundation.org: Suggested the hack] > Signed-off-by: Mel Gorman > --- > mm/page_alloc.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 51e1ded..b13fc29 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1639,8 +1639,8 @@ gfp_to_alloc_flags(gfp_t gfp_mask) > * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will > * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH). > */ > - if (gfp_mask & __GFP_HIGH) > - alloc_flags |= ALLOC_HIGH; > + VM_BUG_ON(__GFP_HIGH != ALLOC_HIGH); > + alloc_flags |= (gfp_mask & __GFP_HIGH); > > if (!wait) { > alloc_flags |= ALLOC_HARDER; Reviewed-by: KOSAKI Motohiro