From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [RFC 7/7] Switch of PF_MEMALLOC during writeout References: <20070820215040.937296148@sgi.com> <20070820215317.441134723@sgi.com> From: Andi Kleen Date: 21 Aug 2007 01:08:06 +0200 In-Reply-To: <20070820215317.441134723@sgi.com> Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: Christoph Lameter writes: > Switch off PF_MEMALLOC during both direct and kswapd reclaim. > > This works because we are not holding any locks at that point because > reclaim is essentially complete. The write occurs when the memory on > the zones is at the high water mark so it is unlikely that writeout > will get into trouble. If so then reclaim can be called recursively to > reclaim more pages. What would stop multiple recursions in extreme low memory cases? Seems risky to me and risking stack overflow. Perhaps define another flag to catch that? -Andi -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org