From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx178.postini.com [74.125.245.178]) by kanga.kvack.org (Postfix) with SMTP id 5B18B6B0068 for ; Tue, 29 May 2012 10:19:07 -0400 (EDT) Date: Tue, 29 May 2012 09:19:02 -0500 (CDT) From: Christoph Lameter Subject: Re: [PATCH v3 05/28] memcg: Reclaim when more than one page needed. In-Reply-To: <1337951028-3427-6-git-send-email-glommer@parallels.com> Message-ID: References: <1337951028-3427-1-git-send-email-glommer@parallels.com> <1337951028-3427-6-git-send-email-glommer@parallels.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Glauber Costa Cc: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, kamezawa.hiroyu@jp.fujitsu.com, Tejun Heo , Li Zefan , Greg Thelen , Suleiman Souhlal , Michal Hocko , Johannes Weiner , devel@openvz.org, David Rientjes On Fri, 25 May 2012, Glauber Costa wrote: > From: Suleiman Souhlal > > mem_cgroup_do_charge() was written before slab accounting, and expects > three cases: being called for 1 page, being called for a stock of 32 pages, > or being called for a hugepage. If we call for 2 pages (and several slabs > used in process creation are such, at least with the debug options I had), > it assumed it's being called for stock and just retried without reclaiming. Slab pages are allocated up to order 3 (PAGE_ALLOC_COSTLY_ORDER). That is 8 pages. > * unlikely to succeed so close to the limit, and we fall back > * to regular pages anyway in case of failure. > */ > - if (nr_pages == 1 && ret) > + if (nr_pages <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER) && ret) { > + cond_resched(); > return CHARGE_RETRY; > + } > > /* > * At task move, charge accounts can be doubly counted. So, it's Ok. That looks correct. -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org