From patchwork Fri May 10 19:56:32 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 10939455 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4327014DB for ; Fri, 10 May 2019 20:01:34 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 322CF28C9B for ; Fri, 10 May 2019 20:01:34 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2666828CCC; Fri, 10 May 2019 20:01:34 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9C51B28C9D for ; Fri, 10 May 2019 20:01:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727914AbfEJUBY (ORCPT ); Fri, 10 May 2019 16:01:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:55244 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728026AbfEJUBM (ORCPT ); Fri, 10 May 2019 16:01:12 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3FEE321841; Fri, 10 May 2019 20:01:11 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.92) (envelope-from ) id 1hPBhe-0006qC-Cz; Fri, 10 May 2019 16:01:10 -0400 Message-Id: <20190510200110.284281830@goodmis.org> User-Agent: quilt/0.65 Date: Fri, 10 May 2019 15:56:32 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-devel@vger.kernel.org Cc: Arnaldo Carvalho de Melo , Ingo Molnar , Jiri Olsa , Namhyung Kim , Andrew Morton , Tzvetomir Stoyanov Subject: [PATCH 26/27] tools/lib/traceevent: Man pages for APIs, used to extract common fields from a record References: <20190510195606.537643615@goodmis.org> MIME-Version: 1.0 Sender: linux-trace-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Tzvetomir Stoyanov Create man pages for libtraceevent APIs: tep_data_type(), tep_data_pid(), tep_data_preempt_count(), tep_data_flags() Link: http://lore.kernel.org/linux-trace-devel/20190503091119.23399-26-tstoyanov@vmware.com Signed-off-by: Tzvetomir Stoyanov [ Fixed missing T in description of NOSUPPORT flag ] Signed-off-by: Steven Rostedt (VMware) --- .../libtraceevent-record_parse.txt | 137 ++++++++++++++++++ 1 file changed, 137 insertions(+) create mode 100644 tools/lib/traceevent/Documentation/libtraceevent-record_parse.txt diff --git a/tools/lib/traceevent/Documentation/libtraceevent-record_parse.txt b/tools/lib/traceevent/Documentation/libtraceevent-record_parse.txt new file mode 100644 index 000000000000..e9a69116c78b --- /dev/null +++ b/tools/lib/traceevent/Documentation/libtraceevent-record_parse.txt @@ -0,0 +1,137 @@ +libtraceevent(3) +================ + +NAME +---- +tep_data_type, tep_data_pid,tep_data_preempt_count, tep_data_flags - +Extract common fields from a record. + +SYNOPSIS +-------- +[verse] +-- +*#include * + +enum *trace_flag_type* { + _TRACE_FLAG_IRQS_OFF_, + _TRACE_FLAG_IRQS_NOSUPPORT_, + _TRACE_FLAG_NEED_RESCHED_, + _TRACE_FLAG_HARDIRQ_, + _TRACE_FLAG_SOFTIRQ_, +}; + +int *tep_data_type*(struct tep_handle pass:[*]_tep_, struct tep_record pass:[*]_rec_); +int *tep_data_pid*(struct tep_handle pass:[*]_tep_, struct tep_record pass:[*]_rec_); +int *tep_data_preempt_count*(struct tep_handle pass:[*]_tep_, struct tep_record pass:[*]_rec_); +int *tep_data_flags*(struct tep_handle pass:[*]_tep_, struct tep_record pass:[*]_rec_); +-- + +DESCRIPTION +----------- +This set of functions can be used to extract common fields from a record. + +The _tep_data_type()_ function gets the event id from the record _rec_. +It reads the "common_type" field. The _tep_ argument is the trace event parser +context. + +The _tep_data_pid()_ function gets the process id from the record _rec_. +It reads the "common_pid" field. The _tep_ argument is the trace event parser +context. + +The _tep_data_preempt_count()_ function gets the preemption count from the +record _rec_. It reads the "common_preempt_count" field. The _tep_ argument is +the trace event parser context. + +The _tep_data_flags()_ function gets the latency flags from the record _rec_. +It reads the "common_flags" field. The _tep_ argument is the trace event parser +context. Supported latency flags are: +[verse] +-- + _TRACE_FLAG_IRQS_OFF_, Interrupts are disabled. + _TRACE_FLAG_IRQS_NOSUPPORT_, Reading IRQ flag is not supported by the architecture. + _TRACE_FLAG_NEED_RESCHED_, Task needs rescheduling. + _TRACE_FLAG_HARDIRQ_, Hard IRQ is running. + _TRACE_FLAG_SOFTIRQ_, Soft IRQ is running. +-- + +RETURN VALUE +------------ +The _tep_data_type()_ function returns an integer, representing the event id. + +The _tep_data_pid()_ function returns an integer, representing the process id + +The _tep_data_preempt_count()_ function returns an integer, representing the +preemption count. + +The _tep_data_flags()_ function returns an integer, representing the latency +flags. Look at the _trace_flag_type_ enum for supported flags. + +All these functions in case of an error return a negative integer. + +EXAMPLE +------- +[source,c] +-- +#include +... +struct tep_handle *tep = tep_alloc(); +... +void process_record(struct tep_record *record) +{ + int data; + + data = tep_data_type(tep, record); + if (data >= 0) { + /* Got the ID of the event */ + } + + data = tep_data_pid(tep, record); + if (data >= 0) { + /* Got the process ID */ + } + + data = tep_data_preempt_count(tep, record); + if (data >= 0) { + /* Got the preemption count */ + } + + data = tep_data_flags(tep, record); + if (data >= 0) { + /* Got the latency flags */ + } +} +... +-- + +FILES +----- +[verse] +-- +*event-parse.h* + Header file to include in order to have access to the library APIs. +*-ltraceevent* + Linker switch to add when building a program that uses the library. +-- + +SEE ALSO +-------- +_libtraceevent(3)_, _trace-cmd(1)_ + +AUTHOR +------ +[verse] +-- +*Steven Rostedt* , author of *libtraceevent*. +*Tzvetomir Stoyanov* , author of this man page. +-- +REPORTING BUGS +-------------- +Report bugs to + +LICENSE +------- +libtraceevent is Free Software licensed under the GNU LGPL 2.1 + +RESOURCES +--------- +https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git