From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754505Ab1GEO5J (ORCPT ); Tue, 5 Jul 2011 10:57:09 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:53264 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753034Ab1GEO5H (ORCPT ); Tue, 5 Jul 2011 10:57:07 -0400 Date: Tue, 5 Jul 2011 16:56:56 +0200 From: Ingo Molnar To: Peter Zijlstra Cc: Cyrill Gorcunov , Don Zickus , Stephane Eranian , Lin Ming , Arnaldo Carvalho de Melo , Frederic Weisbecker , LKML Subject: Re: [PATCH -tip, final] perf, x86: Add hw_watchdog_set_attr() in a sake of nmi-watchdog on P4 Message-ID: <20110705145656.GA18116@elte.hu> References: <20110705110550.GQ17941@sun> <20110705112002.GA15654@elte.hu> <20110705113620.GS17941@sun> <20110705114437.GC15654@elte.hu> <20110705114944.GT17941@sun> <20110705121421.GU17941@sun> <20110705131005.GA5843@elte.hu> <1309871841.3282.148.camel@twins> <20110705133105.GB5843@elte.hu> <1309876851.3282.235.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1309876851.3282.235.camel@twins> User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.3.1 -2.0 BAYES_00 BODY: Bayes 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 * Peter Zijlstra wrote: > On Tue, 2011-07-05 at 15:31 +0200, Ingo Molnar wrote: > > So there's lots of options to fix/improve this more intelligently. > > Sure, and I like the alternative encoding thing best, but doing > that will take time, in the meantime this patch, which is > relatively small (and easy to revert once we get something better > going) does fix a problem for those few unfortunate souls still > using P4 hardware. Well, the BUS_CYCLES thing looks similarly straightforward and should result in an even simpler patch. On P4 BUS_CYCLES would be able to co-exist with CPU_CYCLES so it will solve the P4 issue naturally as well. Thanks, Ingo