xref: /onnv-gate/usr/src/cmd/mdb/demo/README (revision 0:68f95e015346)
1*0Sstevel@tonic-gate#
2*0Sstevel@tonic-gate# CDDL HEADER START
3*0Sstevel@tonic-gate#
4*0Sstevel@tonic-gate# The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate# Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate# (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate# with the License.
8*0Sstevel@tonic-gate#
9*0Sstevel@tonic-gate# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate# or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate# See the License for the specific language governing permissions
12*0Sstevel@tonic-gate# and limitations under the License.
13*0Sstevel@tonic-gate#
14*0Sstevel@tonic-gate# When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate# If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate# fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate# information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate#
20*0Sstevel@tonic-gate# CDDL HEADER END
21*0Sstevel@tonic-gate#
22*0Sstevel@tonic-gate
23*0Sstevel@tonic-gateCopyright (c) 1999 by Sun Microsystems, Inc.
24*0Sstevel@tonic-gateAll rights reserved.
25*0Sstevel@tonic-gate
26*0Sstevel@tonic-gate#ident	"%Z%%M%	%I%	%E% SMI"
27*0Sstevel@tonic-gate
28*0Sstevel@tonic-gate1. Introduction
29*0Sstevel@tonic-gate
30*0Sstevel@tonic-gateThis directory contains source code for sample debugger modules for the Modular
31*0Sstevel@tonic-gateDebugger (MDB).  These modules demonstrate how developers can use the MDB
32*0Sstevel@tonic-gateprogramming API to extend the capabilities of MDB itself.  MDB is an extensible
33*0Sstevel@tonic-gateutility for low-level debugging and editing of the live operating system,
34*0Sstevel@tonic-gateoperating system crash dumps, user processes,  user process core dumps, and
35*0Sstevel@tonic-gateobject files.  For a more detailed description of MDB features and documentation
36*0Sstevel@tonic-gatefor the MDB programming API, refer to the manual, "Solaris Modular Debugger
37*0Sstevel@tonic-gateGuide".  This document is available on-line at http://docs.sun.com and can
38*0Sstevel@tonic-gatebe ordered from Fatbrain.com at http://www1.fatbrain.com/documentation/sun.
39*0Sstevel@tonic-gate
40*0Sstevel@tonic-gate2. Configuration
41*0Sstevel@tonic-gate
42*0Sstevel@tonic-gateAs the files in this directory are owned by the administrator, you should make
43*0Sstevel@tonic-gatea copy of this directory to your home directory or other location before you
44*0Sstevel@tonic-gatebegin experimenting with MDB.  If you wish to change the configuration, edit
45*0Sstevel@tonic-gatethe CC and LINT macro definitions in Makefile.sparc, Makefile.sparcv9, and
46*0Sstevel@tonic-gateMakefile.i386 to point to the appropriate pathnames.  The Makefiles contained
47*0Sstevel@tonic-gatein this directory are set up to use the C compiler (cc) and lint utility found
48*0Sstevel@tonic-gatein your $PATH.  These three Makefiles can also be used to define base compiler
49*0Sstevel@tonic-gatesettings for the corresponding instruction set architecture (ISA):
50*0Sstevel@tonic-gate
51*0Sstevel@tonic-gate	Makefile.sparc		- rules for building 32-bit SPARC objects
52*0Sstevel@tonic-gate	Makefile.sparcv9	- rules for building 64-bit SPARC objects
53*0Sstevel@tonic-gate	Makefile.i386		- rules for building 32-bit IA objects
54*0Sstevel@tonic-gate
55*0Sstevel@tonic-gateThe Makefile.common file adds common compiler and linker flags to these base
56*0Sstevel@tonic-gatedefinitions, and defines the rules for building the example modules.  You will
57*0Sstevel@tonic-gatenot need to change any of the definitions here in order to build the examples.
58*0Sstevel@tonic-gateIf you wish to construct additional modules of your own, edit the MODULES macro
59*0Sstevel@tonic-gateat the top of Makefile.common.  For example, if you create a new module source
60*0Sstevel@tonic-gatefile common/mymodule.c, you should change:
61*0Sstevel@tonic-gate
62*0Sstevel@tonic-gate<	MODULES = example1.so example2.so
63*0Sstevel@tonic-gate
64*0Sstevel@tonic-gateto:
65*0Sstevel@tonic-gate
66*0Sstevel@tonic-gate>	MODULES = example1.so example2.so mymodule.so
67*0Sstevel@tonic-gate
68*0Sstevel@tonic-gateand then execute "make".
69*0Sstevel@tonic-gate
70*0Sstevel@tonic-gate3. Targets
71*0Sstevel@tonic-gate
72*0Sstevel@tonic-gateThe Makefile in this directory supports the following targets:
73*0Sstevel@tonic-gate
74*0Sstevel@tonic-gate	make all (default)	- build all modules for the current machine
75*0Sstevel@tonic-gate	make clean		- remove object files from build directories
76*0Sstevel@tonic-gate	make clean.lint		- remove lint files from build directories
77*0Sstevel@tonic-gate	make clobber		- remove objects, modules, and lint files
78*0Sstevel@tonic-gate	make lint		- run lint against each example module
79*0Sstevel@tonic-gate
80*0Sstevel@tonic-gateTo build the example modules, execute "make" in this directory.  This will
81*0Sstevel@tonic-gateexecute the default "make all" target.
82*0Sstevel@tonic-gate
83*0Sstevel@tonic-gate4. Loading Modules
84*0Sstevel@tonic-gate
85*0Sstevel@tonic-gateAfter you successfully compile the example modules, the module object files
86*0Sstevel@tonic-gatereside in one or more of the i386/, sparc/, and sparcv9/ subdirectories
87*0Sstevel@tonic-gatedepending on the ISAs supported on your machine.  In order to load the example
88*0Sstevel@tonic-gatemodules, you can either use the ::load built-in dcmd with the absolute pathname
89*0Sstevel@tonic-gateof a given module, or you can adjust the module library path to include the
90*0Sstevel@tonic-gatedirectory where your modules are located.  This can be done using the ::set -L
91*0Sstevel@tonic-gatebuilt-in dcmd.  For example:
92*0Sstevel@tonic-gate
93*0Sstevel@tonic-gate	> ::set -L %o:/usr/demo/mdb/%i
94*0Sstevel@tonic-gate	> ::load example1
95*0Sstevel@tonic-gate
96*0Sstevel@tonic-gateThe %o token expands to the old value of the path.  The %i token expands to
97*0Sstevel@tonic-gatethe appropriate ISA name.  You can restore this setting each time you use
98*0Sstevel@tonic-gateMDB by adding the ::set directive to your $HOME/.mdbrc file.  This file, if
99*0Sstevel@tonic-gatepresent, is processed automatically each time you start the debugger.
100*0Sstevel@tonic-gate
101*0Sstevel@tonic-gate5. Example 1: Echo and Vmstat
102*0Sstevel@tonic-gate
103*0Sstevel@tonic-gateThe first example module provides the source code for two example loadable
104*0Sstevel@tonic-gatedcmds.  ::simple_echo is a command to echo back its arguments, similar to
105*0Sstevel@tonic-gate/usr/bin/echo or MDB's built-in ::echo dcmd.  ::vminfo is a command to read
106*0Sstevel@tonic-gateand print the kernel's global virtual memory statistics structure.  This
107*0Sstevel@tonic-gateexample introduces the basic structure of an MDB module and demonstrates some
108*0Sstevel@tonic-gatesimple argument processing.  In order to use ::vminfo, you will need to apply
109*0Sstevel@tonic-gateMDB to a crash dump of your system, or to the live kernel.  To apply MDB to a
110*0Sstevel@tonic-gatecrash dump, you might execute:
111*0Sstevel@tonic-gate
112*0Sstevel@tonic-gate	$ mdb unix.0 vmcore.0
113*0Sstevel@tonic-gate
114*0Sstevel@tonic-gateTo apply MDB to the live kernel, become super-user and then execute:
115*0Sstevel@tonic-gate
116*0Sstevel@tonic-gate	# mdb -k
117*0Sstevel@tonic-gate
118*0Sstevel@tonic-gate6. Example 2: Proc Walker and PS
119*0Sstevel@tonic-gate
120*0Sstevel@tonic-gateThe second example module provides a more realistic example of something you
121*0Sstevel@tonic-gatemight want to do with MDB: print a formatted table of active processes,
122*0Sstevel@tonic-gatesimilar to the /usr/bin/ps command or MDB's ::ps dcmd.  This example
123*0Sstevel@tonic-gateintroduces the concept of a walker, a set of functions which describe how to
124*0Sstevel@tonic-gateiterate over a data structure, and them demonstrates how the ::simple_ps
125*0Sstevel@tonic-gatedcmd can be built using this walker.  Using the simple_proc walker, you can
126*0Sstevel@tonic-gateobtain a listing of kernel proc_t addresses:
127*0Sstevel@tonic-gate
128*0Sstevel@tonic-gate	> ::load example2
129*0Sstevel@tonic-gate	> ::walk simple_proc
130*0Sstevel@tonic-gate	71690a80
131*0Sstevel@tonic-gate	7168ee40
132*0Sstevel@tonic-gate	71611898
133*0Sstevel@tonic-gate	[ ... ]
134*0Sstevel@tonic-gate	7103b178
135*0Sstevel@tonic-gate	7103b888
136*0Sstevel@tonic-gate	1041ce20
137*0Sstevel@tonic-gate
138*0Sstevel@tonic-gateUsing the ::simple_ps dcmd you can obtain a formatted listing of processes:
139*0Sstevel@tonic-gate
140*0Sstevel@tonic-gate	> ::simple_ps
141*0Sstevel@tonic-gate	PID COMM
142*0Sstevel@tonic-gate	285 sh
143*0Sstevel@tonic-gate	271 mibiisa
144*0Sstevel@tonic-gate	269 ttymon
145*0Sstevel@tonic-gate	[ ... ]
146*0Sstevel@tonic-gate
147*0Sstevel@tonic-gate7. Packaging and Installation
148*0Sstevel@tonic-gate
149*0Sstevel@tonic-gateIf you are a software developer, you may wish to develop and deliver MDB
150*0Sstevel@tonic-gatemodules along with your software products in order to facilitate analysis
151*0Sstevel@tonic-gateof software problems at customer sites.  Your completed MDB modules should
152*0Sstevel@tonic-gatebe packaged along with your software and delivered into the appropriate
153*0Sstevel@tonic-gateMDB module directory.  For kernel debugging modules, your module should
154*0Sstevel@tonic-gatebe delivered in one of the following directories:
155*0Sstevel@tonic-gate
156*0Sstevel@tonic-gate	/usr/lib/mdb/kvm
157*0Sstevel@tonic-gate	/usr/platform/`uname -i`/lib/mdb/kvm
158*0Sstevel@tonic-gate
159*0Sstevel@tonic-gateand should be named after your kernel module.  For example, the "ip" kernel
160*0Sstevel@tonic-gatemodule has a debugging module named "ip.so".
161