From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753997AbdK0SIe convert rfc822-to-8bit (ORCPT ); Mon, 27 Nov 2017 13:08:34 -0500 Received: from mx1.redhat.com ([209.132.183.28]:37396 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752566AbdK0SIc (ORCPT ); Mon, 27 Nov 2017 13:08:32 -0500 Subject: Re: [RFC PATCH 1/2] lib: debugobjects: export max loops counter To: Yang Shi , tglx@linutronix.de Cc: linux-kernel@vger.kernel.org References: <1510947833-116482-1-git-send-email-yang.s@alibaba-inc.com> From: Waiman Long Organization: Red Hat Message-ID: <8ea5263b-6733-78fa-f6bd-331eedb39da5@redhat.com> Date: Mon, 27 Nov 2017 13:08:31 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Content-Language: en-US X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Mon, 27 Nov 2017 18:08:32 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/27/2017 12:53 PM, Yang Shi wrote: > Hi Waiman & tglx, > > I'm not sure who is the maintainer for lib/debugobjects.c now, I'm > supposed tglx still is, however, get_maintainer.pl told me Waiman is > the most active developer of this, so added Waiman in this loop in > case he didn't see the patches on LKML. > > Thanks, > Yang > > On 11/17/17 11:43 AM, Yang Shi wrote: >> Currently max chain counter is exported to sysfs, it just record the It is the debugfs, which is different from sysfs. >> counter of inner loop, however, there might be significant iterations of >> external loop then it may take significant amount of time to finish all >> of the checks. This may cuase lockup on !CONFIG_PREEMPT kernel build >> occasionally. >> >> Record the counter of the max loops then export to sysfs so that the >> user can be aware of the real overhead. >> >> Then the output of /sys/kernel/debug/debug_objects/stats looks like: >> >> max_chain :121 >> max_loops :543267 >> warnings :0 >> fixups :0 >> pool_free :1764 >> pool_min_free :341 >> pool_used :86438 >> pool_max_used :268887 >> objs_allocated:6068254 >> objs_freed :5981076 >> >> Signed-off-by: Yang Shi I have no objection to adding one more tracking count. Cheers, Longman