1<?xml version="1.0" encoding="UTF-8"?>
  2<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
  3	"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
  4
  5<book id="Tracepoints">
  6 <bookinfo>
  7  <title>The Linux Kernel Tracepoint API</title>
  8
  9  <authorgroup>
 10   <author>
 11    <firstname>Jason</firstname>
 12    <surname>Baron</surname>
 13    <affiliation>
 14     <address>
 15      <email>jbaron@redhat.com</email>
 16     </address>
 17    </affiliation>
 18   </author>
 19   <author>
 20    <firstname>William</firstname>
 21    <surname>Cohen</surname>
 22    <affiliation>
 23     <address>
 24      <email>wcohen@redhat.com</email>
 25     </address>
 26    </affiliation>
 27   </author>
 28  </authorgroup>
 29
 30  <legalnotice>
 31   <para>
 32     This documentation is free software; you can redistribute
 33     it and/or modify it under the terms of the GNU General Public
 34     License as published by the Free Software Foundation; either
 35     version 2 of the License, or (at your option) any later
 36     version.
 37   </para>
 38
 39   <para>
 40     This program is distributed in the hope that it will be
 41     useful, but WITHOUT ANY WARRANTY; without even the implied
 42     warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 43     See the GNU General Public License for more details.
 44   </para>
 45
 46   <para>
 47     You should have received a copy of the GNU General Public
 48     License along with this program; if not, write to the Free
 49     Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 50     MA 02111-1307 USA
 51   </para>
 52
 53   <para>
 54     For more details see the file COPYING in the source
 55     distribution of Linux.
 56   </para>
 57  </legalnotice>
 58 </bookinfo>
 59
 60 <toc></toc>
 61  <chapter id="intro">
 62   <title>Introduction</title>
 63   <para>
 64     Tracepoints are static probe points that are located in strategic points
 65     throughout the kernel. 'Probes' register/unregister with tracepoints
 66     via a callback mechanism. The 'probes' are strictly typed functions that
 67     are passed a unique set of parameters defined by each tracepoint.
 68   </para>
 69
 70   <para>
 71     From this simple callback mechanism, 'probes' can be used to profile, debug,
 72     and understand kernel behavior. There are a number of tools that provide a
 73     framework for using 'probes'. These tools include Systemtap, ftrace, and
 74     LTTng.
 75   </para>
 76
 77   <para>
 78     Tracepoints are defined in a number of header files via various macros. Thus,
 79     the purpose of this document is to provide a clear accounting of the available
 80     tracepoints. The intention is to understand not only what tracepoints are
 81     available but also to understand where future tracepoints might be added.
 82   </para>
 83
 84   <para>
 85     The API presented has functions of the form:
 86     <function>trace_tracepointname(function parameters)</function>. These are the
 87     tracepoints callbacks that are found throughout the code. Registering and
 88     unregistering probes with these callback sites is covered in the
 89     <filename>Documentation/trace/*</filename> directory.
 90   </para>
 91  </chapter>
 92
 93  <chapter id="irq">
 94   <title>IRQ</title>
 95!Iinclude/trace/events/irq.h
 96  </chapter>
 97
 98  <chapter id="signal">
 99   <title>SIGNAL</title>
100!Iinclude/trace/events/signal.h
101  </chapter>
102
103  <chapter id="block">
104   <title>Block IO</title>
105!Iinclude/trace/events/block.h
106  </chapter>
107
108  <chapter id="workqueue">
109   <title>Workqueue</title>
110!Iinclude/trace/events/workqueue.h
111  </chapter>
112</book>