From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pb0-f48.google.com (mail-pb0-f48.google.com [209.85.160.48]) by kanga.kvack.org (Postfix) with ESMTP id 8FECB6B0035 for ; Thu, 29 May 2014 19:12:56 -0400 (EDT) Received: by mail-pb0-f48.google.com with SMTP id rr13so1016046pbb.21 for ; Thu, 29 May 2014 16:12:56 -0700 (PDT) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTP id ah1si2880167pbc.97.2014.05.29.16.12.55 for ; Thu, 29 May 2014 16:12:55 -0700 (PDT) Date: Thu, 29 May 2014 16:12:53 -0700 From: Andrew Morton Subject: Re: [PATCH] page_alloc: skip cpuset enforcement for lower zone allocations (v4) Message-Id: <20140529161253.73ff978f723972f503123fe8@linux-foundation.org> In-Reply-To: References: <20140523193706.GA22854@amt.cnet> <20140526185344.GA19976@amt.cnet> <53858A06.8080507@huawei.com> <20140528224324.GA1132@amt.cnet> <20140529184303.GA20571@amt.cnet> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: David Rientjes Cc: Marcelo Tosatti , Li Zefan , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Lai Jiangshan , Mel Gorman , Tejun Heo , Christoph Lameter On Thu, 29 May 2014 16:01:55 -0700 (PDT) David Rientjes wrote: > There are still three issues with this, two of which are only minor and > one that needs more thought: > > (1) this doesn't affect only cpusets which the changelog indicates, it > also bypasses mempolicies for GFP_DMA and GFP_DMA32 allocations since > the nodemask != NULL in the page allocator when there is an effective > mempolicy. That may be precisely what you're trying to do (do the > same for mempolicies as you're doing for cpusets), but the comment > now in the code specifically refers to cpusets. Can you make a case > for the mempolicies exception as well? Otherwise, we'll need to do > > if (!nodemask && gfp_zone(gfp_mask) < policy_zone) > nodemask = &node_states[N_ONLINE]; > > And the two minors: > > (2) this should be &node_states[N_MEMORY], not &node_states[N_ONLINE] > since memoryless nodes should not be included. Note that > guarantee_online_mems() looks at N_MEMORY and > cpuset_current_mems_allowed is defined for N_MEMORY without > cpusets. > > (3) it's unnecessary for this to be after the "retry_cpuset" label and > check the gfp mask again if we need to relook at the allowed cpuset > mask. OK, thanks, I made the patch go away for now. -- 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