From patchwork Thu Jul 12 06:40:22 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mel Gorman X-Patchwork-Id: 170572 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 1A5C52C0088 for ; Thu, 12 Jul 2012 16:50:23 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758650Ab2GLGkr (ORCPT ); Thu, 12 Jul 2012 02:40:47 -0400 Received: from cantor2.suse.de ([195.135.220.15]:39762 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752803Ab2GLGko (ORCPT ); Thu, 12 Jul 2012 02:40:44 -0400 Received: from relay1.suse.de (unknown [195.135.220.254]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx2.suse.de (Postfix) with ESMTP id A760EA4386; Thu, 12 Jul 2012 08:40:43 +0200 (CEST) From: Mel Gorman To: Andrew Morton Cc: Linux-MM , Linux-Netdev , LKML , David Miller , Neil Brown , Peter Zijlstra , Mike Christie , Eric B Munson , Eric Dumazet , Sebastian Andrzej Siewior , Mel Gorman Subject: [PATCH 06/16] mm: Ignore mempolicies when using ALLOC_NO_WATERMARK Date: Thu, 12 Jul 2012 07:40:22 +0100 Message-Id: <1342075232-29267-7-git-send-email-mgorman@suse.de> X-Mailer: git-send-email 1.7.9.2 In-Reply-To: <1342075232-29267-1-git-send-email-mgorman@suse.de> References: <1342075232-29267-1-git-send-email-mgorman@suse.de> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The reserve is proportionally distributed over all !highmem zones in the system. So we need to allow an emergency allocation access to all zones. In order to do that we need to break out of any mempolicy boundaries we might have. In my opinion that does not break mempolicies as those are user oriented and not system oriented. That is, system allocations are not guaranteed to be within mempolicy boundaries. For instance IRQs do not even have a mempolicy. So breaking out of mempolicy boundaries for 'rare' emergency allocations, which are always system allocations (as opposed to user) is ok. Signed-off-by: Peter Zijlstra Signed-off-by: Mel Gorman --- mm/page_alloc.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index f88519b..cdc1536 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2350,6 +2350,13 @@ rebalance: /* Allocate without watermarks if the context allows */ if (alloc_flags & ALLOC_NO_WATERMARKS) { + /* + * Ignore mempolicies if ALLOC_NO_WATERMARKS on the grounds + * the allocation is high priority and these type of + * allocations are system rather than user orientated + */ + zonelist = node_zonelist(numa_node_id(), gfp_mask); + page = __alloc_pages_high_priority(gfp_mask, order, zonelist, high_zoneidx, nodemask, preferred_zone, migratetype);