From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with SMTP id C20C26B007E for ; Tue, 10 Nov 2009 22:23:47 -0500 (EST) Received: from m2.gw.fujitsu.co.jp ([10.0.50.72]) by fgwmail5.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id nAB3Njsl015874 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Wed, 11 Nov 2009 12:23:45 +0900 Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 8435E45DE55 for ; Wed, 11 Nov 2009 12:23:45 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (s2.gw.fujitsu.co.jp [10.0.50.92]) by m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 3D46945DE57 for ; Wed, 11 Nov 2009 12:23:45 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id F3972E38004 for ; Wed, 11 Nov 2009 12:23:44 +0900 (JST) Received: from m105.s.css.fujitsu.com (m105.s.css.fujitsu.com [10.249.87.105]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 9674EE3800B for ; Wed, 11 Nov 2009 12:23:44 +0900 (JST) From: KOSAKI Motohiro Subject: Re: [BUGFIX][PATCH] oom-kill: fix NUMA consraint check with nodemask v3 In-Reply-To: References: <20091111115217.FD56.A69D9226@jp.fujitsu.com> Message-Id: <20091111121958.FD59.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Wed, 11 Nov 2009 12:23:43 +0900 (JST) Sender: owner-linux-mm@kvack.org To: David Rientjes Cc: kosaki.motohiro@jp.fujitsu.com, KAMEZAWA Hiroyuki , Daisuke Nishimura , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , Christoph Lameter List-ID: > On Wed, 11 Nov 2009, KOSAKI Motohiro wrote: > > > > > { > > > > -#ifdef CONFIG_NUMA > > > > struct zone *zone; > > > > struct zoneref *z; > > > > enum zone_type high_zoneidx = gfp_zone(gfp_mask); > > > > - nodemask_t nodes = node_states[N_HIGH_MEMORY]; > > > > + int ret = CONSTRAINT_NONE; > > > > > > > > - for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) > > > > - if (cpuset_zone_allowed_softwall(zone, gfp_mask)) > > > > - node_clear(zone_to_nid(zone), nodes); > > > > - else > > > > + /* > > > > + * The nodemask here is a nodemask passed to alloc_pages(). Now, > > > > + * cpuset doesn't use this nodemask for its hardwall/softwall/hierarchy > > > > + * feature. mempolicy is an only user of nodemask here. > > > > + */ > > > > + if (nodemask) { > > > > + nodemask_t mask; > > > > + /* check mempolicy's nodemask contains all N_HIGH_MEMORY */ > > > > + nodes_and(mask, *nodemask, node_states[N_HIGH_MEMORY]); > > > > + if (!nodes_equal(mask, node_states[N_HIGH_MEMORY])) > > > > + return CONSTRAINT_MEMORY_POLICY; > > > > + } > > > > > > Although a nodemask_t was previously allocated on the stack, we should > > > probably change this to use NODEMASK_ALLOC() for kernels with higher > > > CONFIG_NODES_SHIFT since allocations can happen very deep into the stack. > > > > No. NODEMASK_ALLOC() is crap. we should remove it. > > I've booted 1K node systems and have found it to be helpful to ensure that > the stack will not overflow especially in areas where we normally are deep > already, such as in the page allocator. Linux doesn't support 1K nodes. (and only SGI huge machine use 512 nodes) At least, NODEMASK_ALLOC should make more cleaner interface. current one and struct nodemask_scratch are pretty ugly. > > btw, CPUMASK_ALLOC was already removed. > > I don't remember CPUMASK_ALLOC() actually being merged. I know the > comment exists in nodemask.h, but I don't recall any CPUMASK_ALLOC() users > in the tree. -- 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