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diff --git a/share/doc/gdb/In_002dProcess-Agent.html b/share/doc/gdb/In_002dProcess-Agent.html new file mode 100644 index 0000000..faec88a --- /dev/null +++ b/share/doc/gdb/In_002dProcess-Agent.html @@ -0,0 +1,144 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1988-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Free Software" and "Free Software Needs +Free Documentation", with the Front-Cover Texts being "A GNU Manual," +and with the Back-Cover Texts as in (a) below. + +(a) The FSF's Back-Cover Text is: "You are free to copy and modify +this GNU Manual. Buying copies from GNU Press supports the FSF in +developing GNU and promoting software freedom." --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>Debugging with GDB: In-Process Agent</title> + +<meta name="description" content="Debugging with GDB: In-Process Agent"> +<meta name="keywords" content="Debugging with GDB: In-Process Agent"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Concept-Index.html#Concept-Index" rel="index" title="Concept Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="index.html#Top" rel="up" title="Top"> +<link href="In_002dProcess-Agent-Protocol.html#In_002dProcess-Agent-Protocol" rel="next" title="In-Process Agent Protocol"> +<link href="Writing-JIT-Debug-Info-Readers.html#Writing-JIT-Debug-Info-Readers" rel="previous" title="Writing JIT Debug Info Readers"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {margin-left: 3.2em} +kbd {font-style:oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="In_002dProcess-Agent"></a> +<div class="header"> +<p> +Next: <a href="GDB-Bugs.html#GDB-Bugs" accesskey="n" rel="next">GDB Bugs</a>, Previous: <a href="JIT-Interface.html#JIT-Interface" accesskey="p" rel="previous">JIT Interface</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="In_002dProcess-Agent-1"></a> +<h2 class="chapter">30 In-Process Agent</h2> +<a name="index-debugging-agent"></a> +<p>The traditional debugging model is conceptually low-speed, but works fine, +because most bugs can be reproduced in debugging-mode execution. However, +as multi-core or many-core processors are becoming mainstream, and +multi-threaded programs become more and more popular, there should be more +and more bugs that only manifest themselves at normal-mode execution, for +example, thread races, because debugger’s interference with the program’s +timing may conceal the bugs. On the other hand, in some applications, +it is not feasible for the debugger to interrupt the program’s execution +long enough for the developer to learn anything helpful about its behavior. +If the program’s correctness depends on its real-time behavior, delays +introduced by a debugger might cause the program to fail, even when the +code itself is correct. It is useful to be able to observe the program’s +behavior without interrupting it. +</p> +<p>Therefore, traditional debugging model is too intrusive to reproduce +some bugs. In order to reduce the interference with the program, we can +reduce the number of operations performed by debugger. The +<em>In-Process Agent</em>, a shared library, is running within the same +process with inferior, and is able to perform some debugging operations +itself. As a result, debugger is only involved when necessary, and +performance of debugging can be improved accordingly. Note that +interference with program can be reduced but can’t be removed completely, +because the in-process agent will still stop or slow down the program. +</p> +<p>The in-process agent can interpret and execute Agent Expressions +(see <a href="Agent-Expressions.html#Agent-Expressions">Agent Expressions</a>) during performing debugging operations. The +agent expressions can be used for different purposes, such as collecting +data in tracepoints, and condition evaluation in breakpoints. +</p> +<a name="Control-Agent"></a><p>You can control whether the in-process agent is used as an aid for +debugging with the following commands: +</p> +<dl compact="compact"> +<dd><a name="index-set-agent-on"></a> +</dd> +<dt><code>set agent on</code></dt> +<dd><p>Causes the in-process agent to perform some operations on behalf of the +debugger. Just which operations requested by the user will be done +by the in-process agent depends on the its capabilities. For example, +if you request to evaluate breakpoint conditions in the in-process agent, +and the in-process agent has such capability as well, then breakpoint +conditions will be evaluated in the in-process agent. +</p> +<a name="index-set-agent-off"></a> +</dd> +<dt><code>set agent off</code></dt> +<dd><p>Disables execution of debugging operations by the in-process agent. All +of the operations will be performed by <small>GDB</small>. +</p> +<a name="index-show-agent"></a> +</dd> +<dt><code>show agent</code></dt> +<dd><p>Display the current setting of execution of debugging operations by +the in-process agent. +</p></dd> +</dl> + +<table class="menu" border="0" cellspacing="0"> +<tr><td align="left" valign="top">• <a href="In_002dProcess-Agent-Protocol.html#In_002dProcess-Agent-Protocol" accesskey="1">In-Process Agent Protocol</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +</table> + +<hr> +<div class="header"> +<p> +Next: <a href="GDB-Bugs.html#GDB-Bugs" accesskey="n" rel="next">GDB Bugs</a>, Previous: <a href="JIT-Interface.html#JIT-Interface" accesskey="p" rel="previous">JIT Interface</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |