From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757475AbZB0HCP (ORCPT ); Fri, 27 Feb 2009 02:02:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753864AbZB0HB6 (ORCPT ); Fri, 27 Feb 2009 02:01:58 -0500 Received: from e28smtp01.in.ibm.com ([59.145.155.1]:41574 "EHLO e28smtp01.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753662AbZB0HB6 (ORCPT ); Fri, 27 Feb 2009 02:01:58 -0500 Date: Fri, 27 Feb 2009 12:31:48 +0530 From: Balbir Singh To: KAMEZAWA Hiroyuki Cc: "linux-kernel@vger.kernel.org" , kenchen@google.com, "menage@google.com" , "lizf@cn.fujitsu.com" , mingo@elte.hu, "akpm@linux-foundation.org" Subject: Re: [PATCH] change cpuacct usage percpu format Message-ID: <20090227070148.GU11421@balbir.in.ibm.com> Reply-To: balbir@linux.vnet.ibm.com References: <20090227140537.390905c4.kamezawa.hiroyu@jp.fujitsu.com> <20090227063955.GS11421@balbir.in.ibm.com> <20090227155517.9283641b.kamezawa.hiroyu@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20090227155517.9283641b.kamezawa.hiroyu@jp.fujitsu.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * KAMEZAWA Hiroyuki [2009-02-27 15:55:17]: > On Fri, 27 Feb 2009 12:09:55 +0530 > Balbir Singh wrote: > > > * KAMEZAWA Hiroyuki [2009-02-27 14:05:37]: > > > > > I'd like to change cpuacct.usage_percpu format before it's widely used. > > > Current format is not easy to use in hardware with DR feature. > > > > > > == > > > cpuacct.usage_percpu shows per cpu usage information via cgroupfs. > > > It shows all present cpus information and "whose information ?" > > > is explained just by index of data implicitly. > > > > > > IIRC, there is physical cpu hotplug and it can remove > > > cpus and change present map. Considering a software which records > > > this information pediodically(like sar.), its better to show id of cpu > > > in explict way. > > > > > > Signed-off-by: KAMEZAWA Hiroyuki > > > --- > > > kernel/sched.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > Index: mmotm-2.6.29-Feb24/kernel/sched.c > > > =================================================================== > > > --- mmotm-2.6.29-Feb24.orig/kernel/sched.c > > > +++ mmotm-2.6.29-Feb24/kernel/sched.c > > > @@ -9719,7 +9719,7 @@ static int cpuacct_percpu_seq_read(struc > > > > > > for_each_present_cpu(i) { > > > percpu = cpuacct_cpuusage_read(ca, i); > > > - seq_printf(m, "%llu ", (unsigned long long) percpu); > > > + seq_printf(m, "%d %llu\n", i, (unsigned long long) percpu); > > > > Seems like a reasonable change, but I wonder if " " should the > > separator between the CPU and data, I wounder if we should use > > cpu:usage_per_cpu. > > Ah, no strong reason for " ". > > Hmm, like this ? > == > seq_printf(m, "%d: %llu\n", i, (unsigned long long) percpu); > or > seq_printf(m, "%d\t: %llu\n", i, (unsigned long long) percpu); > == > > I'd like to see : and not space after it so something like seq_printf(m, "%d:%llu\n", i, (unsigned long long) percpu); -- Balbir