From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx136.postini.com [74.125.245.136]) by kanga.kvack.org (Postfix) with SMTP id B77EA6B002B for ; Tue, 16 Oct 2012 03:08:42 -0400 (EDT) Received: from mail-ea0-f169.google.com ([209.85.215.169]) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_ARCFOUR_SHA1:16) (Exim 4.71) (envelope-from ) id 1TO1Gb-0000Hd-MM for linux-mm@kvack.org; Tue, 16 Oct 2012 07:08:41 +0000 Received: by mail-ea0-f169.google.com with SMTP id k11so1503354eaa.14 for ; Tue, 16 Oct 2012 00:08:41 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20121016054946.GA3934@barrios> References: <1350278059-14904-1-git-send-email-ming.lei@canonical.com> <1350278059-14904-2-git-send-email-ming.lei@canonical.com> <20121015154724.GA2840@barrios> <20121016054946.GA3934@barrios> Date: Tue, 16 Oct 2012 15:08:41 +0800 Message-ID: Subject: Re: [RFC PATCH 1/3] mm: teach mm by current context info to not do I/O during memory allocation From: Ming Lei Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org List-ID: To: Minchan Kim Cc: linux-kernel@vger.kernel.org, Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-pm@vger.kernel.org, Alan Stern , Oliver Neukum , Jiri Kosina , Andrew Morton , Mel Gorman , KAMEZAWA Hiroyuki , Michal Hocko , Ingo Molnar , Peter Zijlstra , "Rafael J. Wysocki" , linux-mm On Tue, Oct 16, 2012 at 1:49 PM, Minchan Kim wrote: > > Fair enough but it wouldn't be a good idea that add new unlikely branch > in allocator's fast path. Please move the check into slow path which could > be in __alloc_pages_slowpath. Thanks for your comment. I have considered to add the branch into gfp_to_alloc_flags() before, but didn't do it because I see that get_page_from_freelist() may use the GFP_IO or GFP_FS flag at least in zone_reclaim() path. So could you make sure it is safe to move the branch into __alloc_pages_slowpath()? If so, I will add the check into gfp_to_alloc_flags(). Thanks, -- Ming Lei -- 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