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diff --git a/xorg-server/doc/dtrace/Xserver-DTrace.xml b/xorg-server/doc/dtrace/Xserver-DTrace.xml new file mode 100644 index 000000000..e0425c8ee --- /dev/null +++ b/xorg-server/doc/dtrace/Xserver-DTrace.xml @@ -0,0 +1,579 @@ +<?xml version="1.0" encoding="ISO-8859-1"?>
+<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd" [
+ <!ENTITY % defs SYSTEM "/xserver/doc/xml/xserver.ent"> %defs;
+]>
+
+<article id="Xserver-DTrace">
+ <articleinfo>
+ <title>Xserver provider for DTrace</title>
+ <author>
+ <firstname>Alan</firstname><surname>Coopersmith</surname>
+ <affiliation>
+ <orgname>Oracle Corporation</orgname>
+ <orgdiv>Solaris Engineering</orgdiv>
+ </affiliation>
+ </author>
+ <releaseinfo>X.Org Xserver version &xserver.version;</releaseinfo>
+ <legalnotice>
+ <para>
+Copyright (c) 2005, 2006, 2007, 2010, Oracle and/or its affiliates.
+All rights reserved.
+ </para><para>
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+ </para><para>
+The above copyright notice and this permission notice (including the next
+paragraph) shall be included in all copies or substantial portions of the
+Software.
+ </para><para>
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
+ </para>
+ </legalnotice>
+ </articleinfo>
+
+ <sect1 id="introduction">
+ <title>Introduction</title>
+ <para>
+ This page provides details on a
+ <ulink url="http://wikis.sun.com/display/DTrace/Statically+Defined+Tracing+for+User+Applications">statically defined user application tracing provider</ulink>
+ for the
+ <ulink url="http://hub.opensolaris.org/bin/view/Community+Group+dtrace/">DTrace</ulink>
+ facility in <productname>Solaris</productname> 10,
+ <productname>MacOS X</productname> 10.5, and later releases. This
+ provider instruments various points in the X server, to allow
+ tracing what client applications are up to.
+ </para>
+
+ <para>
+ The provider was integrated into the X.Org git master repository
+ with Solaris 10 & OpenSolaris support for the Xserver 1.4 release,
+ released in 2007 with X11R7.3. Support for DTrace on MacOS X
+ was added in Xserver 1.7.
+ </para>
+
+ <para>
+ These probes expose the request and reply structure of the X protocol
+ between clients and the X server, so an understanding of that basic
+ nature will aid in learning how to use these probes.
+ </para>
+ </sect1>
+
+ <sect1 id="probes">
+ <title>Available probes</title>
+
+ <para>
+ Due to the way User-Defined DTrace probes work, arguments to
+ these probes all bear undistinguished names of
+ <parameter>arg0</parameter>, <parameter>arg1</parameter>,
+ <parameter>arg2</parameter>, etc. These tables should help you
+ determine what the real data is for each of the probe arguments.
+
+ <table>
+ <title>Probes and their arguments</title>
+ <tgroup cols='7'>
+ <colspec colname="probe" colwidth="2*"/>
+ <colspec colname="desc" colwidth="3*"/>
+ <colspec colname="arg0" colwidth="1*"/>
+ <colspec colname="arg1" colwidth="1*"/>
+ <colspec colname="arg2" colwidth="1*"/>
+ <colspec colname="arg3" colwidth="1*"/>
+ <colspec colname="arg4" colwidth="1*"/>
+ <spanspec spanname="all" namest="probe" nameend="arg4"/>
+ <thead>
+ <row>
+ <entry>Probe name</entry>
+ <entry>Description</entry>
+ <entry>arg0</entry>
+ <entry>arg1</entry>
+ <entry>arg2</entry>
+ <entry>arg3</entry>
+ <entry>arg4</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry spanname="all" class="grouphead">Request Probes</entry>
+ </row>
+ <row>
+ <entry>request-start</entry>
+ <entry>Called just before processing each client request.</entry>
+ <entry><parameter>requestName</parameter></entry>
+ <entry><parameter>requestCode</parameter></entry>
+ <entry><parameter>requestLength</parameter></entry>
+ <entry><parameter>clientId</parameter></entry>
+ <entry><parameter>requestBuffer</parameter></entry>
+ </row>
+ <row>
+ <entry>request-done</entry>
+ <entry>Called just after processing each client request.</entry>
+ <entry><parameter>requestName</parameter></entry>
+ <entry><parameter>requestCode</parameter></entry>
+ <entry><parameter>sequenceNumber</parameter></entry>
+ <entry><parameter>clientId</parameter></entry>
+ <entry><parameter>resultCode</parameter></entry>
+ </row>
+ <row>
+ <entry spanname="all" class="grouphead">Event Probes</entry>
+ </row>
+ <row>
+ <entry>send-event</entry>
+ <entry>Called just before send each event to a client.</entry>
+ <entry><parameter>clientId</parameter></entry>
+ <entry><parameter>eventCode</parameter></entry>
+ <entry><parameter>eventBuffer</parameter></entry>
+ <entry nameend="arg4" class="unused"/>
+ </row>
+ <row>
+ <entry spanname="all" class="grouphead">Client Connection Probes</entry>
+ </row>
+ <row>
+ <entry>client-connect</entry>
+ <entry>Called when a new connection is opened from a client</entry>
+ <entry><parameter>clientId</parameter></entry>
+ <entry><parameter>clientFD</parameter></entry>
+ <entry nameend="arg4" class="unused"/>
+ </row>
+ <row>
+ <entry>client-auth</entry>
+ <entry>Called when client authenticates (normally just after connection opened)</entry>
+ <entry><parameter>clientId</parameter></entry>
+ <entry><parameter>clientAddr</parameter></entry>
+ <entry><parameter>clientPid</parameter></entry>
+ <entry><parameter>clientZoneId</parameter></entry>
+ <entry nameend="arg4" class="unused"/>
+ </row>
+ <row>
+ <entry>client-disconnect</entry>
+ <entry>Called when a client connection is closed</entry>
+ <entry><parameter>clientId</parameter></entry>
+ <entry nameend="arg4" class="unused"/>
+ </row>
+ <row>
+ <entry spanname="all" class="grouphead">Resource Allocation Probes</entry>
+ </row>
+ <row>
+ <entry>resource-alloc</entry>
+ <entry>Called when a new resource (pixmap, gc, colormap, etc.) is allocated</entry>
+ <entry><parameter>resourceId</parameter></entry>
+ <entry><parameter>resourceTypeId</parameter></entry>
+ <entry><parameter>resourceValue</parameter></entry>
+ <entry><parameter>resourceTypeName</parameter></entry>
+ <entry nameend="arg4" class="unused"/>
+ </row>
+ <row>
+ <entry>resource-free</entry>
+ <entry>Called when a resource is freed</entry>
+ <entry><parameter>resourceId</parameter></entry>
+ <entry><parameter>resourceTypeId</parameter></entry>
+ <entry><parameter>resourceValue</parameter></entry>
+ <entry><parameter>resourceTypeName</parameter></entry>
+ <entry nameend="arg4" class="unused"/>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+ </para>
+ </sect1>
+
+ <sect1 id="arguments">
+ <title>Data Available in Probe Arguments</title>
+
+ <para>
+ To access data in arguments of type <type>string</type>, you will need
+ to use <ulink url="http://wikis.sun.com/display/DTrace/Actions+and+Subroutines#ActionsandSubroutines-{{copyinstr}}"><function>copyinstr()</function></ulink>.
+ To access data buffers referenced via <type>uintptr_t</type>'s, you will
+ need to use <ulink url="http://wikis.sun.com/display/DTrace/Actions+and+Subroutines#ActionsandSubroutines-{{copyin}}"><function>copyin()</function></ulink>.
+
+ <table>
+ <title>Probe Arguments</title>
+ <tgroup cols='3'>
+ <colspec colname="arg" colwidth="2*"/>
+ <colspec colname="type" colwidth="1*"/>
+ <colspec colname="desc" colwidth="7*"/>
+ <thead>
+ <row>
+ <entry>Argument name</entry>
+ <entry>Type</entry>
+ <entry>Description</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><parameter>clientAddr</parameter></entry>
+ <entry><type>string</type></entry>
+ <entry>String representing address client connected from</entry>
+ </row>
+ <row>
+ <entry><parameter>clientFD</parameter></entry>
+ <entry><type>int</type></entry>
+ <entry>X server's file descriptor for server side of each connection</entry>
+ </row>
+ <row>
+ <entry><parameter>clientId</parameter></entry>
+ <entry><type>int</type></entry>
+ <entry>Unique integer identifier for each connection to the
+ X server</entry>
+ </row>
+ <row>
+ <entry><parameter>clientPid</parameter></entry>
+ <entry><type>pid_t</type></entry>
+ <entry>Process id of client, if connection is local
+ (from <function>getpeerucred()</function>)</entry>
+ </row>
+ <row>
+ <entry><parameter>clientZoneId</parameter></entry>
+ <entry><type>zoneid_t</type></entry>
+ <entry>Solaris: Zone id of client, if connection is local
+ (from <function>getpeerucred()</function>)</entry>
+ </row>
+ <row>
+ <entry><parameter>eventBuffer</parameter></entry>
+ <entry><type>uintptr_t</type></entry>
+ <entry>Pointer to buffer containing X event - decode using
+ structures in
+ <<ulink url="http://cgit.freedesktop.org/xorg/proto/xproto/tree/Xproto.h"><filename class="headerfile">X11/Xproto.h</filename></ulink>>
+ and similar headers for each extension</entry>
+ </row>
+ <row>
+ <entry><parameter>eventCode</parameter></entry>
+ <entry><type>uint8_t</type></entry>
+ <entry>Event number of X event</entry>
+ </row>
+ <row>
+ <entry><parameter>resourceId</parameter></entry>
+ <entry><type>uint32_t</type></entry>
+ <entry>X resource id (XID)</entry>
+ </row>
+ <row>
+ <entry><parameter>resourceTypeId</parameter></entry>
+ <entry><type>uint32_t</type></entry>
+ <entry>Resource type id</entry>
+ </row>
+ <row>
+ <entry><parameter>resourceTypeName</parameter></entry>
+ <entry><type>string</type></entry>
+ <entry>String representing X resource type
+ (<literal>"PIXMAP"</literal>, etc.)</entry>
+ </row>
+ <row>
+ <entry><parameter>resourceValue</parameter></entry>
+ <entry><type>uintptr_t</type></entry>
+ <entry>Pointer to data for X resource</entry>
+ </row>
+ <row>
+ <entry><parameter>resultCode</parameter></entry>
+ <entry><type>int</type></entry>
+ <entry>Integer code representing result status of request</entry>
+ </row>
+ <row>
+ <entry><parameter>requestBuffer</parameter></entry>
+ <entry><type>uintptr_t</type></entry>
+ <entry>Pointer to buffer containing X request - decode using
+ structures in
+ <<ulink url="http://cgit.freedesktop.org/xorg/proto/xproto/tree/Xproto.h"><filename class="headerfile">X11/Xproto.h</filename></ulink>>
+ and similar headers for each extension</entry>
+ </row>
+ <row>
+ <entry><parameter>requestCode</parameter></entry>
+ <entry><type>uint8_t</type></entry>
+ <entry>Request number of X request or Extension</entry>
+ </row>
+ <row>
+ <entry><parameter>requestName</parameter></entry>
+ <entry><type>string</type></entry>
+ <entry>Name of X request or Extension</entry>
+ </row>
+ <row>
+ <entry><parameter>requestLength</parameter></entry>
+ <entry><type>uint16_t</type></entry>
+ <entry>Length of X request</entry>
+ </row>
+ <row>
+ <entry><parameter>sequenceNumber</parameter></entry>
+ <entry><type>uint32_t</type></entry>
+ <entry>Number of X request in in this connection</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+ </para>
+ </sect1>
+
+ <sect1 id="examples">
+ <title>Examples</title>
+
+ <example>
+ <title>Counting requests by request name</title>
+
+ <para>
+ This script simply increments a counter for each different request
+ made, and when you exit the script (such as by hitting
+ <keycombo action='simul'><keycap>Control</keycap><keycap>C</keycap>
+ </keycombo>) prints the counts.
+
+ <programlisting>
+#!/usr/sbin/dtrace -s
+
+Xserver*:::request-start
+{
+ @counts[copyinstr(arg0)] = count();
+}
+ </programlisting>
+
+ The output from a short run may appear as:
+ <screen>
+ QueryPointer 1
+ CreatePixmap 2
+ FreePixmap 2
+ PutImage 2
+ ChangeGC 10
+ CopyArea 10
+ CreateGC 14
+ FreeGC 14
+ RENDER 28
+ SetClipRectangles 40
+ </screen>
+ </para>
+
+ <para>
+ This can be rewritten slightly to cache the string containing the name
+ of the request since it will be reused many times, instead of copying
+ it over and over from the kernel:
+
+ <programlisting>
+#!/usr/sbin/dtrace -s
+
+string Xrequest[uintptr_t];
+
+Xserver*:::request-start
+/Xrequest[arg0] == ""/
+{
+ Xrequest[arg0] = copyinstr(arg0);
+}
+
+Xserver*:::request-start
+{
+ @counts[Xrequest[arg0]] = count();
+}
+ </programlisting>
+ </para>
+ </example>
+
+ <example>
+ <title>Get average CPU time per request</title>
+
+ <para>This script records the CPU time used between the probes at
+ the start and end of each request and aggregates it per request type.
+
+ <programlisting>
+#!/usr/sbin/dtrace -s
+
+Xserver*:::request-start
+{
+ reqstart = vtimestamp;
+}
+
+Xserver*:::request-done
+{
+ @times[copyinstr(arg0)] = avg(vtimestamp - reqstart);
+}
+ </programlisting>
+
+ The output from a sample run might look like:
+
+ <screen>
+ ChangeGC 889
+ MapWindow 907
+ SetClipRectangles 1319
+ PolyPoint 1413
+ PolySegment 1434
+ PolyRectangle 1828
+ FreeCursor 1895
+ FreeGC 1950
+ CreateGC 2244
+ FreePixmap 2246
+ GetInputFocus 2249
+ TranslateCoords 8508
+ QueryTree 8846
+ GetGeometry 9948
+ CreatePixmap 12111
+ AllowEvents 14090
+ GrabServer 14791
+ MIT-SCREEN-SAVER 16747
+ ConfigureWindow 22917
+ SetInputFocus 28521
+ PutImage 240841
+
+ </screen>
+ </para>
+ </example>
+
+ <example>
+ <title>Monitoring clients that connect and disconnect</title>
+
+ <para>
+ This script simply prints information about each client that
+ connects or disconnects from the server while it is running.
+ Since the provider is specified as <code>Xserver$1</code> instead
+ of <code>Xserver*</code> like previous examples, it won't monitor
+ all Xserver processes running on the machine, but instead expects
+ the process id of the X server to monitor to be specified as the
+ argument to the script.
+
+ <programlisting>
+#!/usr/sbin/dtrace -s
+
+Xserver$1:::client-connect
+{
+ printf("** Client Connect: id %d\n", arg0);
+}
+
+Xserver$1:::client-auth
+{
+ printf("** Client auth'ed: id %d => %s pid %d\n",
+ arg0, copyinstr(arg1), arg2);
+}
+
+Xserver$1:::client-disconnect
+{
+ printf("** Client Disconnect: id %d\n", arg0);
+}
+ </programlisting>
+
+ A sample run:
+
+ <screen>
+<prompt>#</prompt> <userinput>./foo.d 5790</userinput>
+<computeroutput>dtrace: script './foo.d' matched 4 probes
+CPU ID FUNCTION:NAME
+ 0 15774 CloseDownClient:client-disconnect ** Client Disconnect: id 65
+
+ 2 15774 CloseDownClient:client-disconnect ** Client Disconnect: id 64
+
+ 0 15773 EstablishNewConnections:client-connect ** Client Connect: id 64
+
+ 0 15772 AuthAudit:client-auth ** Client auth'ed: id 64 => local host pid 2034
+
+ 0 15773 EstablishNewConnections:client-connect ** Client Connect: id 65
+
+ 0 15772 AuthAudit:client-auth ** Client auth'ed: id 65 => local host pid 2034
+
+ 0 15774 CloseDownClient:client-disconnect ** Client Disconnect: id 64
+ </computeroutput>
+ </screen>
+
+ </para>
+ </example>
+
+ <example>
+ <title>Monitoring clients creating Pixmaps</title>
+
+ <para>
+ This script can be used to determine which clients are creating
+ pixmaps in the X server, printing information about each client
+ as it connects to help trace it back to the program on the other
+ end of the X connection.
+
+ <programlisting>
+#!/usr/sbin/dtrace -qs
+
+string Xrequest[uintptr_t];
+string Xrestype[uintptr_t];
+
+Xserver$1:::request-start
+/Xrequest[arg0] == ""/
+{
+ Xrequest[arg0] = copyinstr(arg0);
+}
+
+Xserver$1:::resource-alloc
+/arg3 != 0 && Xrestype[arg3] == ""/
+{
+ Xrestype[arg3] = copyinstr(arg3);
+}
+
+
+Xserver$1:::request-start
+/Xrequest[arg0] == "X_CreatePixmap"/
+{
+ printf("-> %s: client %d\n", Xrequest[arg0], arg3);
+}
+
+Xserver$1:::request-done
+/Xrequest[arg0] == "X_CreatePixmap"/
+{
+ printf("<- %s: client %d\n", Xrequest[arg0], arg3);
+}
+
+Xserver$1:::resource-alloc
+/Xrestype[arg3] == "PIXMAP"/
+{
+ printf("** Pixmap alloc: %08x\n", arg0);
+}
+
+
+Xserver$1:::resource-free
+/Xrestype[arg3] == "PIXMAP"/
+{
+ printf("** Pixmap free: %08x\n", arg0);
+}
+
+Xserver$1:::client-connect
+{
+ printf("** Client Connect: id %d\n", arg0);
+}
+
+Xserver$1:::client-auth
+{
+ printf("** Client auth'ed: id %d => %s pid %d\n",
+ arg0, copyinstr(arg1), arg2);
+}
+
+Xserver$1:::client-disconnect
+{
+ printf("** Client Disconnect: id %d\n", arg0);
+}
+ </programlisting>
+
+ Sample output from a run of this script:
+ <screen><computeroutput>
+** Client Connect: id 17
+** Client auth'ed: id 17 => local host pid 20273
+-> X_CreatePixmap: client 17
+** Pixmap alloc: 02200009
+<- X_CreatePixmap: client 17
+-> X_CreatePixmap: client 15
+** Pixmap alloc: 01e00180
+<- X_CreatePixmap: client 15
+-> X_CreatePixmap: client 15
+** Pixmap alloc: 01e00181
+<- X_CreatePixmap: client 15
+-> X_CreatePixmap: client 14
+** Pixmap alloc: 01c004c8
+<- X_CreatePixmap: client 14
+** Pixmap free: 02200009
+** Client Disconnect: id 17
+** Pixmap free: 01e00180
+** Pixmap free: 01e00181
+ </computeroutput></screen>
+
+ </para>
+
+ </example>
+
+
+ </sect1>
+
+</article>
+
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