From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758437AbYCTUX2 (ORCPT ); Thu, 20 Mar 2008 16:23:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755426AbYCTUVT (ORCPT ); Thu, 20 Mar 2008 16:21:19 -0400 Received: from viefep32-int.chello.at ([62.179.121.50]:40691 "EHLO viefep32-int.chello.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754966AbYCTUVL (ORCPT ); Thu, 20 Mar 2008 16:21:11 -0400 Message-Id: <20080320202122.439298000@chello.nl> References: <20080320201042.675090000@chello.nl> User-Agent: quilt/0.45-1 Date: Thu, 20 Mar 2008 21:10:52 +0100 From: Peter Zijlstra To: Linus Torvalds , Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, trond.myklebust@fys.uio.no, neilb@suse.de, miklos@szeredi.hu, penberg@cs.helsinki.fi, a.p.zijlstra@chello.nl Subject: [PATCH 10/30] mm: system wide ALLOC_NO_WATERMARK Content-Disposition: inline; filename=global-ALLOC_NO_WATERMARKS.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@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 don't 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 --- mm/page_alloc.c | 6 ++++++ 1 file changed, 6 insertions(+) Index: linux-2.6/mm/page_alloc.c =================================================================== --- linux-2.6.orig/mm/page_alloc.c +++ linux-2.6/mm/page_alloc.c @@ -1625,6 +1625,12 @@ restart: rebalance: if (alloc_flags & ALLOC_NO_WATERMARKS) { nofail_alloc: + /* + * break out of mempolicy boundaries + */ + zonelist = NODE_DATA(numa_node_id())->node_zonelists + + gfp_zone(gfp_mask); + /* go through the zonelist yet again, ignoring mins */ page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist, high_zoneidx, ALLOC_NO_WATERMARKS); --