Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756136AbZCUPwY (ORCPT ); Sat, 21 Mar 2009 11:52:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752547AbZCUPwP (ORCPT ); Sat, 21 Mar 2009 11:52:15 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:55444 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753564AbZCUPwO (ORCPT ); Sat, 21 Mar 2009 11:52:14 -0400 Date: Sat, 21 Mar 2009 16:52:02 +0100 From: Ingo Molnar To: Andrew Morton Cc: Paul Mackerras , Peter Zijlstra , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] perfcounters: record time running and time enabled for each counter Message-ID: <20090321155202.GA6356@elte.hu> References: <18884.55232.197620.696687@cargo.ozlabs.ibm.com> <20090321055252.eb0673ea.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090321055252.eb0673ea.akpm@linux-foundation.org> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1011 Lines: 36 * Andrew Morton wrote: > > + u64 time_enabled; > > + u64 time_running; > > These look like times. I see no indication (here) as to the units. > > > + u64 start_enabled; > > This looks like a boolean, but it's u64. > > > + u64 start_running; > > hard to say. > > > + u64 last_stopped; > > probably a time, unknown units. > > > Perhaps one of the reasons why this code is confusing is the > blurring between the "time" at which an event occured and the > "time" between the occurrence of two events. A weakness in > English, I guess. Using the term "interval" in the latter case > will help a lot. What we use in the scheduler is "sum_time" or "runtime". A bit of a tongue twister but unambiguous. Ingo -- 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/