From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755967AbdESJIm (ORCPT ); Fri, 19 May 2017 05:08:42 -0400 Received: from mga07.intel.com ([134.134.136.100]:33179 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754974AbdESJAl (ORCPT ); Fri, 19 May 2017 05:00:41 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.38,363,1491289200"; d="scan'208";a="1132489074" From: Adrian Hunter To: Arnaldo Carvalho de Melo , Andi Kleen Cc: linux-kernel@vger.kernel.org Subject: [PATCH 07/37] perf intel-pt: Ensure never to set 'last_ip' when packet 'count' is zero Date: Fri, 19 May 2017 11:54:06 +0300 Message-Id: <1495184076-23805-8-git-send-email-adrian.hunter@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1495184076-23805-1-git-send-email-adrian.hunter@intel.com> References: <1495184076-23805-1-git-send-email-adrian.hunter@intel.com> Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Intel PT uses IP compression based on the last IP. For decoding purposes, 'last IP' is not updated when a branch target has been suppressed, which is indicated by IPBytes == 0. IPBytes is stored in the packet 'count', so ensure never to set 'last_ip' when packet 'count' is zero. Signed-off-by: Adrian Hunter --- tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c index f8fada859f12..4359177a0504 100644 --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c @@ -1450,7 +1450,8 @@ static int intel_pt_walk_psbend(struct intel_pt_decoder *decoder) case INTEL_PT_FUP: decoder->pge = true; - intel_pt_set_last_ip(decoder); + if (decoder->packet.count) + intel_pt_set_last_ip(decoder); break; case INTEL_PT_MODE_TSX: @@ -1740,8 +1741,9 @@ static int intel_pt_walk_trace(struct intel_pt_decoder *decoder) static inline bool intel_pt_have_ip(struct intel_pt_decoder *decoder) { - return decoder->have_last_ip || decoder->packet.count == 0 || - decoder->packet.count == 3 || decoder->packet.count == 6; + return decoder->packet.count && + (decoder->have_last_ip || decoder->packet.count == 3 || + decoder->packet.count == 6); } /* Walk PSB+ packets to get in sync. */ -- 1.9.1