From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755016AbZECA10 (ORCPT ); Sat, 2 May 2009 20:27:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753277AbZECA1N (ORCPT ); Sat, 2 May 2009 20:27:13 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:60684 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752929AbZECA1M (ORCPT ); Sat, 2 May 2009 20:27:12 -0400 From: "Rafael J. Wysocki" To: Andrew Morton Subject: [PATCH 1/4] mm: Add __GFP_NO_OOM_KILL flag Date: Sun, 3 May 2009 02:22:06 +0200 User-Agent: KMail/1.11.2 (Linux/2.6.30-rc4-rjw; KDE/4.2.2; x86_64; ; ) Cc: pavel@ucw.cz, torvalds@linux-foundation.org, jens.axboe@oracle.com, alan-jenkins@tuffmail.co.uk, linux-kernel@vger.kernel.org, kernel-testers@vger.kernel.org, linux-pm@lists.linux-foundation.org References: <20090502104947.2720f173.akpm@linux-foundation.org> <200905030220.57933.rjw@sisk.pl> In-Reply-To: <200905030220.57933.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200905030222.07360.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andrew Morton > > Remind me: why can't we just allocate N pages at suspend-time? > > We need half of memory free. The reason we can't "just allocate" is > probably OOM killer; but my memories are quite weak :-(. hm. You'd think that with our splendid range of __GFP_foo falgs, there would be some combo which would suit this requirement but I can't immediately spot one. We can always add another I guess. Something like... Signed-off-by: Rafael J. Wysocki --- include/linux/gfp.h | 3 ++- mm/page_alloc.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) Index: linux-2.6/mm/page_alloc.c =================================================================== --- linux-2.6.orig/mm/page_alloc.c +++ linux-2.6/mm/page_alloc.c @@ -1620,7 +1620,8 @@ nofail_alloc: } /* The OOM killer will not help higher order allocs so fail */ - if (order > PAGE_ALLOC_COSTLY_ORDER) { + if (order > PAGE_ALLOC_COSTLY_ORDER || + (gfp_mask & __GFP_NO_OOM_KILL)) { clear_zonelist_oom(zonelist, gfp_mask); goto nopage; } Index: linux-2.6/include/linux/gfp.h =================================================================== --- linux-2.6.orig/include/linux/gfp.h +++ linux-2.6/include/linux/gfp.h @@ -51,8 +51,9 @@ struct vm_area_struct; #define __GFP_THISNODE ((__force gfp_t)0x40000u)/* No fallback, no policies */ #define __GFP_RECLAIMABLE ((__force gfp_t)0x80000u) /* Page is reclaimable */ #define __GFP_MOVABLE ((__force gfp_t)0x100000u) /* Page is movable */ +#define __GFP_NO_OOM_KILL ((__force gfp_t)0x200000u) /* Don't invoke out_of_memory() */ -#define __GFP_BITS_SHIFT 21 /* Room for 21 __GFP_FOO bits */ +#define __GFP_BITS_SHIFT 22 /* Number of__GFP_FOO bits */ #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1)) /* This equals 0, but use constants in case they ever change */