Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755304Ab3HWOCC (ORCPT ); Fri, 23 Aug 2013 10:02:02 -0400 Received: from a10-51.smtp-out.amazonses.com ([54.240.10.51]:41597 "EHLO a10-51.smtp-out.amazonses.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755205Ab3HWOCA (ORCPT ); Fri, 23 Aug 2013 10:02:00 -0400 X-Greylist: delayed 1140 seconds by postgrey-1.27 at vger.kernel.org; Fri, 23 Aug 2013 10:02:00 EDT Date: Fri, 23 Aug 2013 13:42:59 +0000 From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Joonsoo Kim cc: Pekka Enberg , Andrew Morton , David Rientjes , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 05/16] slab: remove cachep in struct slab_rcu In-Reply-To: <20130823065315.GG22605@lge.com> Message-ID: <00000140ab69e6be-3b2999b6-93b4-4b22-a91f-8929aee5238f-000000@email.amazonses.com> References: <1377161065-30552-1-git-send-email-iamjoonsoo.kim@lge.com> <1377161065-30552-6-git-send-email-iamjoonsoo.kim@lge.com> <00000140a72870a6-f7c87696-ecbc-432c-9f41-93f414c0c623-000000@email.amazonses.com> <20130823065315.GG22605@lge.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-SES-Outgoing: 2013.08.23-54.240.10.51 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 836 Lines: 22 On Fri, 23 Aug 2013, Joonsoo Kim wrote: > On Thu, Aug 22, 2013 at 05:53:00PM +0000, Christoph Lameter wrote: > > On Thu, 22 Aug 2013, Joonsoo Kim wrote: > > > > > We can get cachep using page in struct slab_rcu, so remove it. > > > > Ok but this means that we need to touch struct page. Additional cacheline > > in cache footprint. > > In following patch, we overload RCU_HEAD to LRU of struct page and > also overload struct slab to struct page. So there is no > additional cacheline footprint at final stage. If you do not use rcu (standard case) then you have an additional cacheline. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/