Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751818AbdFOQjl (ORCPT ); Thu, 15 Jun 2017 12:39:41 -0400 Received: from mail-io0-f179.google.com ([209.85.223.179]:32777 "EHLO mail-io0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752099AbdFOQji (ORCPT ); Thu, 15 Jun 2017 12:39:38 -0400 MIME-Version: 1.0 In-Reply-To: <37D7C6CF3E00A74B8858931C1DB2F0775370DC74@SHSMSX103.ccr.corp.intel.com> References: <1497534989-29231-1-git-send-email-eranian@google.com> <1497534989-29231-3-git-send-email-eranian@google.com> <37D7C6CF3E00A74B8858931C1DB2F0775370DC74@SHSMSX103.ccr.corp.intel.com> From: Stephane Eranian Date: Thu, 15 Jun 2017 09:39:36 -0700 Message-ID: Subject: Re: [PATCH 2/5] perf/x86: add PERF_SAMPLE_SKID_IP support for X86 PEBS To: "Liang, Kan" Cc: "linux-kernel@vger.kernel.org" , "acme@redhat.com" , "peterz@infradead.org" , "mingo@elte.hu" , "ak@linux.intel.com" , "jolsa@redhat.com" Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1440 Lines: 42 On Thu, Jun 15, 2017 at 8:40 AM, Liang, Kan wrote: > > >> This patch adds support for SKID_IP to Intel x86 processors in PEBS mode. In >> that case, the off-by-1 IP from PEBS is returned in the SKID_IP field. > > It looks we can only get different skid_ip and ip with :pp event (attr.precise = 2). > With the :p event (attr.precise = 1), the skid_ip and ip are the same. Right? > Correct, because skid_ip would be equal to the pebs->ip. > Thanks, > Kan > >> >> Signed-off-by: Stephane Eranian >> --- >> arch/x86/events/intel/ds.c | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c index >> c6d23ffe422d..ee17de5d6b8d 100644 >> --- a/arch/x86/events/intel/ds.c >> +++ b/arch/x86/events/intel/ds.c >> @@ -1169,6 +1169,13 @@ static void setup_pebs_sample_data(struct >> perf_event *event, >> x86_pmu.intel_cap.pebs_format >= 1) >> data->addr = pebs->dla; >> >> + /* >> + * unmodified, skid IP which is guaranteed to be the next >> + * dyanmic instruction >> + */ >> + if (sample_type & PERF_SAMPLE_SKID_IP) >> + data->skid_ip = pebs->ip; >> + >> if (x86_pmu.intel_cap.pebs_format >= 2) { >> /* Only set the TSX weight when no memory weight. */ >> if ((sample_type & PERF_SAMPLE_WEIGHT) && !fll) >> -- >> 2.13.1.518.g3df882009-goog >