From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753144AbdDLFoy (ORCPT ); Wed, 12 Apr 2017 01:44:54 -0400 Received: from terminus.zytor.com ([65.50.211.136]:44089 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752982AbdDLFom (ORCPT ); Wed, 12 Apr 2017 01:44:42 -0400 Date: Tue, 11 Apr 2017 22:40:03 -0700 From: tip-bot for David Carrillo-Cisneros Message-ID: Cc: hpa@zytor.com, alexander.shishkin@linux.intel.com, acme@redhat.com, peterz@infradead.org, pjt@google.com, sque@chromium.org, linux-kernel@vger.kernel.org, davidcc@google.com, eranian@google.com, tglx@linutronix.de, hekuang@huawei.com, jolsa@kernel.org, mingo@kernel.org, wangnan0@huawei.com, mhiramat@kernel.org, ak@linux.intel.com Reply-To: linux-kernel@vger.kernel.org, tglx@linutronix.de, eranian@google.com, davidcc@google.com, wangnan0@huawei.com, mhiramat@kernel.org, mingo@kernel.org, jolsa@kernel.org, hekuang@huawei.com, ak@linux.intel.com, alexander.shishkin@linux.intel.com, hpa@zytor.com, acme@redhat.com, sque@chromium.org, peterz@infradead.org, pjt@google.com In-Reply-To: <20170410201432.24807-4-davidcc@google.com> References: <20170410201432.24807-4-davidcc@google.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf tools: Describe pipe mode in perf.data-file-fomat.txt Git-Commit-ID: 6d13491e2d4944180c9b4fb6ddca4e34b1537836 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 6d13491e2d4944180c9b4fb6ddca4e34b1537836 Gitweb: http://git.kernel.org/tip/6d13491e2d4944180c9b4fb6ddca4e34b1537836 Author: David Carrillo-Cisneros AuthorDate: Mon, 10 Apr 2017 13:14:28 -0700 Committer: Arnaldo Carvalho de Melo CommitDate: Tue, 11 Apr 2017 15:23:41 -0300 perf tools: Describe pipe mode in perf.data-file-fomat.txt Add a minimal description of pipe's data format. Signed-off-by: David Carrillo-Cisneros Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Andi Kleen Cc: He Kuang Cc: Masami Hiramatsu Cc: Paul Turner Cc: Peter Zijlstra Cc: Simon Que Cc: Stephane Eranian Cc: Wang Nan Link: http://lkml.kernel.org/r/20170410201432.24807-4-davidcc@google.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf.data-file-format.txt | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/tools/perf/Documentation/perf.data-file-format.txt b/tools/perf/Documentation/perf.data-file-format.txt index b664b18..fa2a913 100644 --- a/tools/perf/Documentation/perf.data-file-format.txt +++ b/tools/perf/Documentation/perf.data-file-format.txt @@ -11,8 +11,8 @@ All fields are in native-endian of the machine that generated the perf.data. When perf is writing to a pipe it uses a special version of the file format that does not rely on seeking to adjust data offsets. This -format is not described here. The pipe version can be converted to -normal perf.data with perf inject. +format is described in "Pipe-mode data" section. The pipe data version can be +augmented with additional events using perf inject. The file starts with a perf_header: @@ -411,6 +411,21 @@ An array bound by the perf_file_section size. ids points to a array of uint64_t defining the ids for event attr attr. +Pipe-mode data + +Pipe-mode avoid seeks in the file by removing the perf_file_section and flags +from the struct perf_header. The trimmed header is: + +struct perf_pipe_file_header { + u64 magic; + u64 size; +}; + +The information about attrs, data, and event_types is instead in the +synthesized events PERF_RECORD_ATTR, PERF_RECORD_HEADER_TRACING_DATA and +PERF_RECORD_HEADER_EVENT_TYPE that are generated by perf record in pipe-mode. + + References: include/uapi/linux/perf_event.h