2009-04-30 13:29:42 -04:00
										 
									 
								 
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								<?xml version="1.0" encoding="UTF-8"?>
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								<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
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									"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
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								<book id="Tracepoints">
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								 <bookinfo>
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								  <title>The Linux Kernel Tracepoint API</title>
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								  <authorgroup>
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								   <author>
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								    <firstname>Jason</firstname>
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								    <surname>Baron</surname>
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								    <affiliation>
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								     <address>
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								      <email>jbaron@redhat.com</email>
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								     </address>
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								    </affiliation>
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								   </author>
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											2010-03-09 09:26:04 +01:00
										 
									 
								 
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								   <author>
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								    <firstname>William</firstname>
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								    <surname>Cohen</surname>
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								    <affiliation>
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								     <address>
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								      <email>wcohen@redhat.com</email>
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								     </address>
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								    </affiliation>
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								   </author>
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											2009-04-30 13:29:42 -04:00
										 
									 
								 
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								  </authorgroup>
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								  <legalnotice>
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								   <para>
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								     This documentation is free software; you can redistribute
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								     it and/or modify it under the terms of the GNU General Public
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								     License as published by the Free Software Foundation; either
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								     version 2 of the License, or (at your option) any later
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								     version.
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								   </para>
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								   <para>
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								     This program is distributed in the hope that it will be
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								     useful, but WITHOUT ANY WARRANTY; without even the implied
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								     warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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								     See the GNU General Public License for more details.
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								   </para>
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								   <para>
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								     You should have received a copy of the GNU General Public
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								     License along with this program; if not, write to the Free
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								     Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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								     MA 02111-1307 USA
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								   </para>
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								   <para>
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								     For more details see the file COPYING in the source
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								     distribution of Linux.
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								   </para>
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								  </legalnotice>
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								 </bookinfo>
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								 <toc></toc>
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								  <chapter id="intro">
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								   <title>Introduction</title>
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								   <para>
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								     Tracepoints are static probe points that are located in strategic points
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								     throughout the kernel. 'Probes' register/unregister with tracepoints
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								     via a callback mechanism. The 'probes' are strictly typed functions that
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								     are passed a unique set of parameters defined by each tracepoint.
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								   </para>
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								   <para>
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								     From this simple callback mechanism, 'probes' can be used to profile, debug,
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								     and understand kernel behavior. There are a number of tools that provide a
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								     framework for using 'probes'. These tools include Systemtap, ftrace, and
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								     LTTng.
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								   </para>
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								   <para>
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								     Tracepoints are defined in a number of header files via various macros. Thus,
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								     the purpose of this document is to provide a clear accounting of the available
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								     tracepoints. The intention is to understand not only what tracepoints are
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								     available but also to understand where future tracepoints might be added.
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								   </para>
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								   <para>
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								     The API presented has functions of the form:
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								     <function>trace_tracepointname(function parameters)</function>. These are the
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								     tracepoints callbacks that are found throughout the code. Registering and
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								     unregistering probes with these callback sites is covered in the
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								     <filename>Documentation/trace/*</filename> directory.
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								   </para>
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								  </chapter>
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											2009-04-30 13:29:47 -04:00
										 
									 
								 
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								  <chapter id="irq">
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								   <title>IRQ</title>
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								!Iinclude/trace/events/irq.h
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								  </chapter>
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											2009-11-24 16:56:45 -05:00
										 
									 
								 
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								  <chapter id="signal">
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								   <title>SIGNAL</title>
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								!Iinclude/trace/events/signal.h
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								  </chapter>
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											2010-03-09 09:26:04 +01:00
										 
									 
								 
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								  <chapter id="block">
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								   <title>Block IO</title>
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								!Iinclude/trace/events/block.h
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								  </chapter>
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											2010-08-26 10:35:43 -04:00
										 
									 
								 
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								  <chapter id="workqueue">
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								   <title>Workqueue</title>
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								!Iinclude/trace/events/workqueue.h
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								  </chapter>
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											2009-04-30 13:29:42 -04:00
										 
									 
								 
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								</book>
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