Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751572AbaFEMpc (ORCPT ); Thu, 5 Jun 2014 08:45:32 -0400 Received: from mail-oa0-f43.google.com ([209.85.219.43]:51274 "EHLO mail-oa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750939AbaFEMpa (ORCPT ); Thu, 5 Jun 2014 08:45:30 -0400 MIME-Version: 1.0 In-Reply-To: <20140604222857.GB16855@tassilo.jf.intel.com> References: <1401917658-26065-1-git-send-email-eranian@google.com> <20140604222857.GB16855@tassilo.jf.intel.com> Date: Thu, 5 Jun 2014 14:45:29 +0200 Message-ID: Subject: Re: [PATCH 0/9] perf/x86: implement HT counter corruption workaround From: Stephane Eranian To: Andi Kleen Cc: LKML , Peter Zijlstra , "mingo@elte.hu" , Jiri Olsa , "Yan, Zheng" , Maria Dimakopoulou Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 5, 2014 at 12:28 AM, Andi Kleen wrote: >> There is no HW or FW workaround for this problem. > > Actually there is for global measurements: > > measure with Any bit set and divide by two. > > Please add a check that the any bit is set, and disable > the workaround for that case. > I think this assume same event is measured on sibling counters at any time. Otherwise, how does that eliminate the corruption? -- 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/