From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754093Ab1DTTMx (ORCPT ); Wed, 20 Apr 2011 15:12:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41204 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752058Ab1DTTMw (ORCPT ); Wed, 20 Apr 2011 15:12:52 -0400 Date: Wed, 20 Apr 2011 15:12:31 -0400 From: Don Zickus To: Cyrill Gorcunov Cc: linux-kernel@vger.kernel.org, mingo@elte.hu, peterz@infradead.org, robert.richter@amd.com, andi@firstfloor.org, ming.m.lin@intel.com, eranian@google.com, ying.huang@intel.com, mathieu.desnoyers@efficios.com, acme@redhat.com Subject: Re: [RFC] x86, perf: high volume of events produces a flood of unknown NMIs Message-ID: <20110420191231.GB31724@redhat.com> References: <20110420182613.GA31724@redhat.com> <4DAF2A57.1010804@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4DAF2A57.1010804@gmail.com> User-Agent: Mutt/1.5.20 (2009-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 20, 2011 at 10:47:51PM +0400, Cyrill Gorcunov wrote: > > Or perhaps we don't care about this because in the end perf can't even > > capture the data without spitting out a CPU Overload message. > > > > Thoughts? > > > > Hi Don, just a thought -- since pmi masks lvtpc we could read it and check if it's > masked or no, though I fear it is quite time consuming operation in compare with > frames :( (hmm, intel spec mentions only p4 and xeon as masking lvtpc) Been there, tried that. It seems to be masked a large majority of the time, even when the NMIs don't appear to be back-to-back. Cheers, Don