Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755944Ab0KPReq (ORCPT ); Tue, 16 Nov 2010 12:34:46 -0500 Received: from mtagate5.uk.ibm.com ([194.196.100.165]:59706 "EHLO mtagate5.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753372Ab0KPReo (ORCPT ); Tue, 16 Nov 2010 12:34:44 -0500 Subject: Re: [RFC][PATCH v2 5/7] taskstats: Improve cumulative CPU time accounting From: Michael Holzheu Reply-To: holzheu@linux.vnet.ibm.com To: Oleg Nesterov Cc: Shailabh Nagar , Andrew Morton , Venkatesh Pallipadi , Suresh Siddha , Peter Zijlstra , Ingo Molnar , John stultz , Thomas Gleixner , Balbir Singh , Martin Schwidefsky , Heiko Carstens , Roland McGrath , linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org In-Reply-To: <20101113183810.GA9021@redhat.com> References: <20101111170352.732381138@linux.vnet.ibm.com> <20101111170815.404670062@linux.vnet.ibm.com> <20101113183810.GA9021@redhat.com> Content-Type: text/plain; charset="us-ascii" Organization: IBM Date: Tue, 16 Nov 2010 18:34:40 +0100 Message-ID: <1289928880.1940.116.camel@holzheu-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1797 Lines: 42 Hello Oleg, On Sat, 2010-11-13 at 19:38 +0100, Oleg Nesterov wrote: > I already asked you to split these changes, perhaps you can do this? > Say, bacct_add_tsk() looks overcomplicated, the change in copy_process() > shouldn't introduce the new CLONE_THREAD check, not sure I understand > why release_task() was chosen for reparenting, other nits... I want to establish the new hierarchy when a new process is forked and not for new threads, therefore the check for CLONE_THREAD in copy_process(). I do the reparenting with reparent_acct() when a process dies, therefore the check for "group_dead" in exit_signal(). > But it is not easy to discuss these completely different things > looking at the single patch. > > Imho, it would be much better if you make a separate patch which > adds acct_parent/etc and implements the parallel hierarchy. This > also makes sense because it touches the core kernel. > > Personally I think that even "struct cdata" + __account_ctime() helper > needs a separate patch, and perhaps this change makes sense by itself > as cleanup. And this way the "trivial" changes (like the changes in > k_getrusage) won't distract from the functional changes. > > The final change should introduce cdata_acct and actually implement > the complete cumulative accounting. So you want to have the following three patches: * Introduce "struct cdata" + __account_ctime() (no functional change) * Add cdata_acct accounting + parallel accounting hierarchy * Add taskstats interface to export the data to userspace Correct? Michael -- 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/