Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753879Ab0H0ILk (ORCPT ); Fri, 27 Aug 2010 04:11:40 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:60934 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753382Ab0H0ILh convert rfc822-to-8bit (ORCPT ); Fri, 27 Aug 2010 04:11:37 -0400 Subject: Re: [PATCH -v3] perf, x86: try to handle unknown nmis with running perfctrs From: Peter Zijlstra To: Robert Richter Cc: Cyrill Gorcunov , Don Zickus , Ingo Molnar , Lin Ming , "fweisbec@gmail.com" , "linux-kernel@vger.kernel.org" , "Huang, Ying" , Yinghai Lu , Andi Kleen In-Reply-To: <20100827075737.GE22783@erda.amd.com> References: <20100825094819.GB3198@erda.amd.com> <20100825104130.GA27891@elte.hu> <20100825110006.GB27891@elte.hu> <20100825201106.GH4879@redhat.com> <20100826090008.GA22783@erda.amd.com> <20100826152246.GN4879@redhat.com> <20100826153404.GA6306@lenovo> <20100826164031.GO4879@redhat.com> <20100826180250.GB6306@lenovo> <20100827075737.GE22783@erda.amd.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Fri, 27 Aug 2010 10:11:21 +0200 Message-ID: <1282896681.1975.1760.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1195 Lines: 32 On Fri, 2010-08-27 at 09:57 +0200, Robert Richter wrote: > On 26.08.10 14:02:50, Cyrill Gorcunov wrote: > > > diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c > > > index 4539b4b..9e65a7b 100644 > > > --- a/arch/x86/kernel/cpu/perf_event_intel.c > > > +++ b/arch/x86/kernel/cpu/perf_event_intel.c > > > @@ -777,7 +777,9 @@ again: > > > > > > done: > > > intel_pmu_enable_all(0); > > > - return handled; > > > + if (!handled) > > > + return handled; > > > + return ++handled; > > > } > > > > > > static struct event_constraint * > > > > > > > ok, it seems it just treat any unknown nmi as being came from PMU, no? > > Yes, this just throws away all unknown nmis after a perf nmi. It > disables unknown nmi detection on this cpu type. Wouldn't returning 2 be more sensible, then it would only eat a few unknowns after each pmi? (Still assuming you return 0 when there really was nothing to do) -- 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/