From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932303AbaBKTn4 (ORCPT ); Tue, 11 Feb 2014 14:43:56 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:40287 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753961AbaBKTHe (ORCPT ); Tue, 11 Feb 2014 14:07:34 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Christoph Lameter , Wanpeng Li , Li Zefan , Pekka Enberg Subject: [PATCH 3.10 15/79] slub: Fix calculation of cpu slabs Date: Tue, 11 Feb 2014 11:05:19 -0800 Message-Id: <20140211184721.372293555@linuxfoundation.org> X-Mailer: git-send-email 1.8.5.1.163.gd7aced9 In-Reply-To: <20140211184720.928667275@linuxfoundation.org> References: <20140211184720.928667275@linuxfoundation.org> User-Agent: quilt/0.61-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Li Zefan commit 8afb1474db4701d1ab80cd8251137a3260e6913e upstream. /sys/kernel/slab/:t-0000048 # cat cpu_slabs 231 N0=16 N1=215 /sys/kernel/slab/:t-0000048 # cat slabs 145 N0=36 N1=109 See, the number of slabs is smaller than that of cpu slabs. The bug was introduced by commit 49e2258586b423684f03c278149ab46d8f8b6700 ("slub: per cpu cache for partial pages"). We should use page->pages instead of page->pobjects when calculating the number of cpu partial slabs. This also fixes the mapping of slabs and nodes. As there's no variable storing the number of total/active objects in cpu partial slabs, and we don't have user interfaces requiring those statistics, I just add WARN_ON for those cases. Acked-by: Christoph Lameter Reviewed-by: Wanpeng Li Signed-off-by: Li Zefan Signed-off-by: Pekka Enberg Signed-off-by: Greg Kroah-Hartman --- mm/slub.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) --- a/mm/slub.c +++ b/mm/slub.c @@ -4285,7 +4285,13 @@ static ssize_t show_slab_objects(struct page = ACCESS_ONCE(c->partial); if (page) { - x = page->pobjects; + node = page_to_nid(page); + if (flags & SO_TOTAL) + WARN_ON_ONCE(1); + else if (flags & SO_OBJECTS) + WARN_ON_ONCE(1); + else + x = page->pages; total += x; nodes[node] += x; }