From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S940319AbdEZIeY (ORCPT ); Fri, 26 May 2017 04:34:24 -0400 Received: from mga06.intel.com ([134.134.136.31]:6270 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759379AbdEZIXn (ORCPT ); Fri, 26 May 2017 04:23:43 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.38,396,1491289200"; d="scan'208";a="1153074146" From: Adrian Hunter To: Arnaldo Carvalho de Melo , Andi Kleen Cc: linux-kernel@vger.kernel.org Subject: [PATCH V2 06/37] perf intel-pt: Ensure never to set 'last_ip' when packet 'count' is zero Date: Fri, 26 May 2017 11:17:07 +0300 Message-Id: <1495786658-18063-7-git-send-email-adrian.hunter@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1495786658-18063-1-git-send-email-adrian.hunter@intel.com> References: <1495786658-18063-1-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 Cc: stable@vger.kernel.org --- 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 62e2c2ad3f1d..72b9dc8135a2 100644 --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c @@ -1470,7 +1470,8 @@ 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: @@ -1756,8 +1757,9 @@ 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