From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753715Ab3ARP34 (ORCPT ); Fri, 18 Jan 2013 10:29:56 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:31801 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752083Ab3ARP3y (ORCPT ); Fri, 18 Jan 2013 10:29:54 -0500 X-Authority-Analysis: v=2.0 cv=bJmU0YCZ c=1 sm=0 a=rXTBtCOcEpjy1lPqhTCpEQ==:17 a=mNMOxpOpBa8A:10 a=HJMuRcDKq34A:10 a=5SG0PmZfjMsA:10 a=Q9fys5e9bTEA:10 a=meVymXHHAAAA:8 a=RPfT3mj6-UMA:10 a=GE73Nj82zm6kZl7SA38A:9 a=PUjeQqilurYA:10 a=rXTBtCOcEpjy1lPqhTCpEQ==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 74.67.115.198 Message-ID: <1358522992.7383.13.camel@gandalf.local.home> Subject: Re: [RFC][PATCH v2] slub: Keep page and object in sync in slab_alloc_node() From: Steven Rostedt To: Joonsoo Kim Cc: Christoph Lameter , LKML , linux-mm , Andrew Morton , Pekka Enberg , Matt Mackall , Thomas Gleixner , RT , Clark Williams , John Kacur , "Luis Claudio R. Goncalves" Date: Fri, 18 Jan 2013 10:29:52 -0500 In-Reply-To: <20130118044242.GA18665@lge.com> References: <1358446258.23211.32.camel@gandalf.local.home> <1358447864.23211.34.camel@gandalf.local.home> <0000013c4a69a2cf-1a19a6f6-e6a3-4f06-99a4-10fdd4b9aca2-000000@email.amazonses.com> <1358458996.23211.46.camel@gandalf.local.home> <0000013c4a7e7fbf-c51fd42a-2455-4fec-bb37-915035956f05-000000@email.amazonses.com> <1358462763.23211.57.camel@gandalf.local.home> <1358464245.23211.62.camel@gandalf.local.home> <1358464837.23211.66.camel@gandalf.local.home> <1358468598.23211.67.camel@gandalf.local.home> <1358468924.23211.69.camel@gandalf.local.home> <20130118044242.GA18665@lge.com> Content-Type: text/plain; charset="ISO-8859-15" X-Mailer: Evolution 3.4.4-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2013-01-18 at 13:42 +0900, Joonsoo Kim wrote: > diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h > index 9db4825..b54dffa 100644 > --- a/include/linux/slub_def.h > +++ b/include/linux/slub_def.h > @@ -46,6 +46,9 @@ enum stat_item { > struct kmem_cache_cpu { > void **freelist; /* Pointer to next available object */ > unsigned long tid; /* Globally unique transaction id */ > +#ifdef CONFIG_NUMA > + int node; Note, you put an int between a long and a pointer, which will waste 4 bytes on 64bit machines. > +#endif > struct page *page; /* The slab from which we are allocating */ > struct page *partial; /* Partially allocated frozen slabs */ > #ifdef CONFIG_SLUB_STATS > @@ -2038,10 +2049,10 @@ static void flush_all(struct kmem_cache *s) > * Check if the objects in a per cpu structure fit numa > * locality expectations. > */ > -static inline int node_match(struct page *page, int node) > +static inline int node_match(struct kmem_cache_cpu *c, int node) > { > #ifdef CONFIG_NUMA > - if (node != NUMA_NO_NODE && page_to_nid(page) != node) > + if (node != NUMA_NO_NODE && c->node != node) We still have the issue of cpu fetching c->node before c->tid and c->freelist. I still believe the only solution is to prevent the task from migrating via a preempt disable. -- Steve