Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754518Ab3HVVuN (ORCPT ); Thu, 22 Aug 2013 17:50:13 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:54974 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754027Ab3HVVuK (ORCPT ); Thu, 22 Aug 2013 17:50:10 -0400 X-IronPort-AV: E=Sophos;i="4.89,936,1367971200"; d="scan'208";a="44538407" From: Zoltan Kiss To: Konrad Rzeszutek Wilk , Rob Landley , Jiri Kosina , Mathieu Desnoyers , Steven Rostedt , Paul Bolle , , CC: Zoltan Kiss Subject: [PATCH] Documentation/trace: Correcting and extending tracepoint documentation Date: Thu, 22 Aug 2013 22:49:31 +0100 Message-ID: <1377208171-9004-1-git-send-email-zoltan.kiss@citrix.com> X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.80.2.133] X-DLP: MIA2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2100 Lines: 64 The sample missed the moving of the header files into the events subdirectory. I've also extended it based on the existing headers, and mentioned the tiny but important role of CREATE_TRACE_POINTS. Signed-off-by: Zoltan Kiss --- Documentation/trace/tracepoints.txt | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/Documentation/trace/tracepoints.txt b/Documentation/trace/tracepoints.txt index da49437..e8e3c4b 100644 --- a/Documentation/trace/tracepoints.txt +++ b/Documentation/trace/tracepoints.txt @@ -40,7 +40,13 @@ Two elements are required for tracepoints : In order to use tracepoints, you should include linux/tracepoint.h. -In include/trace/subsys.h : +In include/trace/events/subsys.h : + +#undef TRACE_SYSTEM +#define TRACE_SYSTEM subsys + +#if !defined(_TRACE_SUBSYS_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_SUBSYS_H #include @@ -48,10 +54,16 @@ DECLARE_TRACE(subsys_eventname, TP_PROTO(int firstarg, struct task_struct *p), TP_ARGS(firstarg, p)); +#endif /* _TRACE_SUBSYS_H */ + +/* This part must be outside protection */ +#include + In subsys/file.c (where the tracing statement must be added) : -#include +#include +#define CREATE_TRACE_POINTS DEFINE_TRACE(subsys_eventname); void somefct(void) @@ -72,6 +84,9 @@ Where : - TP_ARGS(firstarg, p) are the parameters names, same as found in the prototype. +- if you use the header in multiple source files, #define CREATE_TRACE_POINTS + should appear only in one source file + Connecting a function (probe) to a tracepoint is done by providing a probe (function to call) for the specific tracepoint through register_trace_subsys_eventname(). Removing a probe is done through -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/