From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 938ACC43381 for ; Fri, 8 Mar 2019 13:37:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6FBFB2087C for ; Fri, 8 Mar 2019 13:37:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726706AbfCHNhP (ORCPT ); Fri, 8 Mar 2019 08:37:15 -0500 Received: from mail-wr1-f67.google.com ([209.85.221.67]:42272 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726613AbfCHNhP (ORCPT ); Fri, 8 Mar 2019 08:37:15 -0500 Received: by mail-wr1-f67.google.com with SMTP id r5so21382004wrg.9 for ; Fri, 08 Mar 2019 05:37:13 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=a/rHvcNAVSxUe96RX1fH+jJRbSx39a+JiDDGo5Umc3Y=; b=E+l3UzgUYCXKJSQIwp/wgA+kc+XE+iHtMeTnPdOrz0LklX6fffQfljO7AlkuHLmzUt VhPgZWsHT5/eGSaK6ZwVHxHnwcIb0TeO69eSA6KGjAm21qIwMSl34zP9DXKzU8dpT9eF PCOSMpALgUz+3mBe27EiE/F5ytGKw2NGc151Lb54MqRX9JmMDuV4tNPO4Zr/rriXDVaX x4+NA++Ae3QMJJBee9uDwg45vQg6SbCg9MeZbMC3oDbVSpxtxMIH8jb4rbwXaiC9ZvqK YPQBVbSq5/2+5LDoTTn5MFrvKhyHdPn+p3dEP6P+mm3pjJ6ek5AeTAqWOspAm2siG4Ko HN5g== X-Gm-Message-State: APjAAAXXV8Md+ZWm3/Yl86fWWh7S0X+7oeZ8e4ogjQhJq1e/ey1eWxUk Pe9EAKKLDXhPpvyeUnl7O0wD2RTt X-Google-Smtp-Source: APXvYqxHXlS/nPiBV1gXu5M5Vrv6udzQ87IBQsU8DagUSkEDnYqqxkIVrEB/gOyMD7PzNEoAB2TSiw== X-Received: by 2002:adf:9f54:: with SMTP id f20mr11289614wrg.88.1552052232579; Fri, 08 Mar 2019 05:37:12 -0800 (PST) Received: from oberon.eng.vmware.com ([146.247.46.5]) by smtp.gmail.com with ESMTPSA id 132sm19625364wmd.27.2019.03.08.05.37.11 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 08 Mar 2019 05:37:11 -0800 (PST) From: Tzvetomir Stoyanov To: rostedt@goodmis.org Cc: linux-trace-devel@vger.kernel.org Subject: [PATCH v4 16/46] tools/lib/traceevent: Man pages for tep_register_print_function() and tep_unregister_print_function() Date: Fri, 8 Mar 2019 15:36:24 +0200 Message-Id: <20190308133654.21264-17-tstoyanov@vmware.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190308133654.21264-1-tstoyanov@vmware.com> References: <20190308133654.21264-1-tstoyanov@vmware.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-trace-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org Create man pages for tep_register_print_function() and tep_unregister_print_function() as part of the libtraceevent APIs. Signed-off-by: Tzvetomir Stoyanov --- .../libtraceevent-reg_print_func.txt | 128 ++++++++++++++++++ 1 file changed, 128 insertions(+) create mode 100644 tools/lib/traceevent/Documentation/libtraceevent-reg_print_func.txt diff --git a/tools/lib/traceevent/Documentation/libtraceevent-reg_print_func.txt b/tools/lib/traceevent/Documentation/libtraceevent-reg_print_func.txt new file mode 100644 index 000000000000..59cef18b71f1 --- /dev/null +++ b/tools/lib/traceevent/Documentation/libtraceevent-reg_print_func.txt @@ -0,0 +1,128 @@ +libtraceevent(3) +================ + +NAME +---- +tep_register_print_function,tep_unregister_print_function - Registers / Unregisters +a helper function. + +SYNOPSIS +-------- +[verse] +-- +*#include * + +enum *tep_func_arg_type* { + TEP_FUNC_ARG_VOID, + TEP_FUNC_ARG_INT, + TEP_FUNC_ARG_LONG, + TEP_FUNC_ARG_STRING, + TEP_FUNC_ARG_PTR, + TEP_FUNC_ARG_MAX_TYPES +}; + +typedef unsigned long long (*pass:[*]tep_func_handler*)(struct trace_seq pass:[*]s, unsigned long long pass:[*]args); + +int *tep_register_print_function*(struct tep_handle pass:[*]_tep_, tep_func_handler _func_, enum tep_func_arg_type _ret_type_, char pass:[*]_name_, _..._); +int *tep_unregister_print_function*(struct tep_handle pass:[*]_tep_, tep_func_handler _func_, char pass:[*]_name_); +-- + +DESCRIPTION +----------- +Some events may have helper functions in the print format arguments. This allows +a plugin to dynamically create a way to process one of these functions. + +The _tep_register_print_function()_ registers such helper function. The _tep_ +argument is the trace event parser context. The _func_ argument is the address +of the helper function. The _ret_type_ argument is the return type of the +helper function, value from the _tep_func_arg_type_ enum. The _name_ is the name +of the helper function, as seen in the print format arguments. The _..._ is a +variable list of _tep_func_arg_type_ enums, the _func_ function arguments. +This list must end with _TEP_FUNC_ARG_VOID_. + +The _tep_unregister_print_function()_ unregisters a helper function, previously +registered with _tep_register_print_function()_. The _tep_ argument is the +trace event parser context. The _func_ and _name_ arguments are the same, used +when the helper function was registered. + +The _tep_func_handler_ is the type of the helper function. The _s_ argument is +the trace sequence, it can be used to create a custom string. +The _args_ is a list of arguments, defined when the helper function was +registered. + +RETURN VALUE +------------ +The _tep_register_print_function()_ function returns 0 in case of success. +In case of an error, TEP_ERRNO_... code is returned. + +The _tep_unregister_print_function()_ returns 0 in case of success, or -1 in +case of an error. + +EXAMPLE +------- +[source,c] +-- +#include +#include +... +struct tep_handle *tep = tep_alloc(); +... +static long long +process_custom_helper(struct trace_seq *s, unsigned long long *args) +{ + unsigned long long param = args[0]; + trace_seq_printf(s, "the helper was called, with argument %lld", param); + return 0; +} +... + if ( tep_register_print_function(tep, + process_custom_helper, + TEP_FUNC_ARG_STRING, + "custom_helper", + TEP_FUNC_ARG_LONG, + TEP_FUNC_ARG_VOID) != 0) { + /* Failed to register my process_custom_helper function */ + } +... + if (tep_unregister_print_function(tep, process_custom_helper, + "custom_helper") != 0) { + /* Failed to unregister my process_custom_helper function */ + } +-- + +FILES +----- +[verse] +-- +*event-parse.h* + Header file to include in order to have access to the library APIs. +*trace-seq.h* + Header file to include in order to have access to trace sequences related APIs. + Trace sequences are used to allow a function to call several other functions + to create a string of data to use. +*-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 -- 2.20.1