Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754591Ab0HYV2W (ORCPT ); Wed, 25 Aug 2010 17:28:22 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:40108 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754565Ab0HYV2T convert rfc822-to-8bit (ORCPT ); Wed, 25 Aug 2010 17:28:19 -0400 Subject: Re: [patch 1/5] mm: add nofail variants of kmalloc kcalloc and kzalloc From: Peter Zijlstra To: David Rientjes Cc: Theodore Tso , Jens Axboe , Andrew Morton , Neil Brown , Alasdair G Kergon , Chris Mason , Steven Whitehouse , Jan Kara , Frederic Weisbecker , "linux-raid@vger.kernel.org" , "linux-btrfs@vger.kernel.org" , "cluster-devel@redhat.com" , "linux-ext4@vger.kernel.org" , "reiserfs-devel@vger.kernel.org" , "linux-kernel@vger.kernel.org" In-Reply-To: References: <1282656558.2605.2742.camel@laptop> <4C73CA24.3060707@fusionio.com> <20100825112433.GB4453@thunk.org> <1282736132.2605.3563.camel@laptop> <20100825115709.GD4453@thunk.org> <1282740516.2605.3644.camel@laptop> <1282740778.2605.3652.camel@laptop> <1282743090.2605.3696.camel@laptop> <1282769729.1975.96.camel@laptop> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Wed, 25 Aug 2010 23:27:57 +0200 Message-ID: <1282771677.1975.138.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1121 Lines: 24 On Wed, 2010-08-25 at 14:11 -0700, David Rientjes wrote: > > There's still no hard guarantee that the memory will allocatable > (GFP_KERNEL, the compaction, then GFP_ATOMIC could all still fail), but I > don't see how continuously looping the page allocator is possibly supposed > to help in these situations. Why do you think I'm a proponent of that behaviour? I've been arguing that the existance of GFP_NOFAIL is the bug, and I started the whole discussion because your patchset didn't outline the purpose of its existance, it merely changes __GFP_NOFAIL usage into $foo_nofail() functions, which on its own is a rather daft change. Optimizing the page allocator by removing those conditional from its innards into an outer loop not used by most callers seems a fine goal, but you didn't state that. Also, I like the postfix proposed by Andi better: _i_suck() :-) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/