From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753667AbYKYK7f (ORCPT ); Tue, 25 Nov 2008 05:59:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752800AbYKYK7Q (ORCPT ); Tue, 25 Nov 2008 05:59:16 -0500 Received: from one.firstfloor.org ([213.235.205.2]:58122 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752766AbYKYK7Q (ORCPT ); Tue, 25 Nov 2008 05:59:16 -0500 Date: Tue, 25 Nov 2008 12:09:35 +0100 From: Andi Kleen To: KOSAKI Motohiro Cc: Andi Kleen , Robert Richter , Ingo Molnar , LKML Subject: Re: [2.6.28-rc6] oprofile: "opcontrol --start" output two warnings Message-ID: <20081125110935.GF6703@one.firstfloor.org> References: <20081125121212.26C3.KOSAKI.MOTOHIRO@jp.fujitsu.com> <87ljv8ce2j.fsf@basil.nowhere.org> <20081125192316.26E5.KOSAKI.MOTOHIRO@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20081125192316.26E5.KOSAKI.MOTOHIRO@jp.fujitsu.com> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > if so, I think get_stagger() is a bit strange. > it depend on caller cpu. then if PREEMPT=Y, it return radom result. Even without PREEMPT it is random because there is no guarantee the init code is executing on CPU 0 > > I'm not sure about oprofile design. > but if you are right, I think p4_fill_in_addresses shoudn't use smp_processor_id(). Correct. > > Am I missing any point? No you're right. Always returning 0 in get_stagger() should be ok I think, at least it wouldn't make anything worse. Or perhaps figure out if the per cpu addresses are really needed, if yes then this would need much more changes. But I hope that would not be needed. But someone should better test it, the P4 perfmon handling is certainly hairy and I don't claim to understand all its intricate details. -Andi -- ak@linux.intel.com