Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757393AbZFYT4Q (ORCPT ); Thu, 25 Jun 2009 15:56:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753998AbZFYT4A (ORCPT ); Thu, 25 Jun 2009 15:56:00 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:35742 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752687AbZFYTz7 (ORCPT ); Thu, 25 Jun 2009 15:55:59 -0400 Date: Thu, 25 Jun 2009 12:55:39 -0700 From: Andrew Morton To: Theodore Tso Cc: rientjes@google.com, torvalds@linux-foundation.org, penberg@cs.helsinki.fi, arjan@infradead.org, linux-kernel@vger.kernel.org, cl@linux-foundation.org, npiggin@suse.de Subject: Re: upcoming kerneloops.org item: get_page_from_freelist Message-Id: <20090625125539.74e3507e.akpm@linux-foundation.org> In-Reply-To: <20090625194423.GB6472@mit.edu> References: <20090624123624.26c93459.akpm@linux-foundation.org> <20090624130121.99321cca.akpm@linux-foundation.org> <20090624150714.c7264768.akpm@linux-foundation.org> <20090625132544.GB9995@mit.edu> <20090625193806.GA6472@mit.edu> <20090625194423.GB6472@mit.edu> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1301 Lines: 30 On Thu, 25 Jun 2009 15:44:23 -0400 Theodore Tso wrote: > On Thu, Jun 25, 2009 at 03:38:06PM -0400, Theodore Tso wrote: > > Hmm, is there a reason to avoid using GFP_ATOMIC on the first > > allocation, and only adding GFP_ATOMIC after the first failure? > > Never mind, stupid question; I hit the send button before thinking > about this enough. Obviously we should try without GFP_ATOMIC so the > allocator can try to release some memory. One use GFP_KERNEL|__GFP_HIGH, which bestows GFP_ATOMIC's special reserve-dipping powers upon GFP_KERNEL. Maybe one could set PF_MEMALLOC on kjournald too, as it is a thing which can clean memory, as long as it is given a bit of memory itself. This would be a risky step. In fact they're both risky steps, because the block layer needs memory too. If JBD uses __GFP_HIGH/PF_MEMALLOC tricks to get more memory, that just deprives the block layer of some. OTOH the block layer uses special immortal mepools to avoid starvation. otoh2, ext3 can be backed by devices other than plain old disks. -- 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/