Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757539Ab1ELOW7 (ORCPT ); Thu, 12 May 2011 10:22:59 -0400 Received: from mail-iy0-f174.google.com ([209.85.210.174]:55706 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755202Ab1ELOW6 convert rfc822-to-8bit (ORCPT ); Thu, 12 May 2011 10:22:58 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=Zwxz5yANJRDMdM0dY0mbGSacpVx4VA1g4GogR6OC/tpKHL9ASAgAGhJOGPpqOUNYhX CeYMUOoWyGrF7Bag2ASbcEXfNABPKofv1wPA9ujECv2E2Zk1cYKYM73TTay8R96UeaJl fLCrC51t5FM+f2zVA+OVnt1fj/11iU00uTSiM= MIME-Version: 1.0 In-Reply-To: <20110512122658.GB3639@zhy> References: <4DCAB8A2.8060605@linux.com> <20110512105756.GA3329@zhy> <4DCBCE56.2010607@gmail.com> <20110512122658.GB3639@zhy> Date: Thu, 12 May 2011 22:22:57 +0800 Message-ID: Subject: Re: lock_stat &rq->lock/1 class name meaning From: =?UTF-8?Q?Am=C3=A9rico_Wang?= To: Yong Zhang Cc: Juri Lelli , linux-kernel@vger.kernel.org, Peter Zijlstra , Ingo Molnar Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1568 Lines: 41 On Thu, May 12, 2011 at 8:26 PM, Yong Zhang wrote: > On Thu, May 12, 2011 at 02:11:02PM +0200, Juri Lelli wrote: >> Thanks! >> >> On 05/12/2011 12:57 PM, Yong Zhang wrote: >> >On Wed, May 11, 2011 at 06:26:10PM +0200, Juri Lelli wrote: >> >>Hi, >> >>I'm trying to collect contention statistics through /proc/lock_stat >> >>about scheduler data structures. >> >> >> >>What I obtain if a do "cat /proc/lock_stat" is something like: >> >>... >> >>&rq->lock:         13128          13128           0.43 >> >>[...] >> >> >> >>I guess the first one is about the per-rq (per-CPU) spinlock, but >> >>what about the second? What the "/1" stands for? >> > >> >It is also rq but it's subclass is 1. >> > >> >Take a look at raw_spin_lock_nested(&this_rq->lock, SINGLE_DEPTH_NESTING); >> >in _double_lock_balance() >> >> Ok, I've put more light on this also looking at lockdep.h comments >> and lockdep-design documentation. >> >> Since I'm probably not the only one having troubles undestanding >> lock_stat output, maybe could be useful to add something on this >> inside lockstat documentation (I can try to do this). What you >> think? > > Any improvement will be good :) I think Documentation/lockstat.txt is out of date, the last change of this file can be back to Thu Nov 19 13:54:05 2009. -- 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/