1 LTTNG USERSPACE TRACER (LTTng-UST)
2 ----------------------------
4 UST web site: http://lttng.org/lttng2.0
6 Updated versions of this package may be found at:
8 * Website: http://lttng.org/lttng2.0
9 * Releases: http://lttng.org/files/lttng-ust
10 * GitWeb: http://git.lttng.org (project: lttng-ust)
11 * Git: git://git.lttng.org/lttng-ust.git
17 Userspace RCU library, by Mathieu Desnoyers and Paul E. McKenney
19 -> This release depends on liburcu v0.7.2
21 * Debian/Ubuntu package: liburcu-dev
22 * Website: http://lttng.org/urcu
23 * Releases: http://lttng.org/files/urcu
24 * GitWeb: http://lttng.org/cgi-bin/gitweb.cgi?p=userspace-rcu.git;a=summary
25 * Git: git://lttng.org/userspace-rcu.git
28 * Debian/Ubuntu package: libuuid1, uuid-dev
30 For developers using the git tree:
32 This source tree is based on the autotools suite from GNU to simplify
33 portability. Here are some things you should have on your system in order to
34 compile the git repository tree :
36 - GNU autotools (automake >=1.10, autoconf >=2.50, autoheader >=2.50)
37 (make sure your system wide "automake" points to a recent version!)
39 (for more information, go to http://www.gnu.org/software/autoconf/)
41 If you get the tree from the repository, you will need to use the "bootstrap"
42 script in the root of the tree. It calls all the GNU tools needed to prepare the
46 INSTALLATION INSTRUCTIONS:
48 - Download, compile and install liburcu.
49 - In this package's tree, run ./configure.
54 If compiling from the git repository, run ./bootstrap before running
55 the configure script, to generate it.
60 - Create an instrumentation header following the tracepoint examples.
61 See lttng/tracepoint.h, and examples.
63 There are 2 ways to compile the Tracepoint Provider with the
64 application: either statically or dynamically. Please follow
67 1.1) Compile the Tracepoint provider with the application, either
68 directly or through a static library (.a):
69 - Into exactly one object of your application: define
70 "TRACEPOINT_DEFINE" and include the tracepoint provider.
71 - Use "-I." for the compilation unit containing the tracepoint
72 provider include (e.g. tp.c).
73 - Link application with "-ldl" on Linux, with "-lc" on BSD.
74 - If building the provider directly into the application,
75 link the application with "-llttng-ust".
76 - If building a static library for the provider, link the static
77 library with "-llttng-ust".
78 - Include the tracepoint provider header into all C files using
81 - tests/hello/ hello.c tp.c ust_tests_hello.h Makefile.example.*
83 2) Compile the Tracepoint Provider separately from the application,
84 using dynamic linking:
85 - Into exactly one object of your application: define
86 "TRACEPOINT_DEFINE" _and_ also define
87 "TRACEPOINT_PROBE_DYNAMIC_LINKAGE", then include the tracepoint
89 - Include the tracepoint provider header into all instrumented C
90 files that use the provider.
91 - Compile the tracepoint provider with "-I.".
92 - Link the tracepoint provider with "-llttng-ust".
93 - Link application with "-ldl" on Linux, "-lc" on BSD.
94 - Set a LD_PRELOAD environment to preload the tracepoint provider
95 shared object before starting the application when tracing is
96 needed. Another way is to dlopen the tracepoint probe when needed
99 - tests/demo/ demo.c tp*.c ust_tests_demo*.h demo-trace
101 - Enable instrumentation and control tracing with the "lttng" command
102 from lttng-tools. See lttng-tools doc/quickstart.txt.
103 - Note about dlclose() usage: it is not safe to use dlclose on a
104 provider shared object that is being actively used for tracing due
105 to a lack of reference counting from lttng-ust to the used shared
108 ENVIRONMENT VARIABLES:
110 - liblttng-ust debug can be activated by setting the environment variable
111 "LTTNG_UST_DEBUG" when launching the application. It can also be enabled
112 at compile-time by compiling libust with -DLTTNG_UST_DEBUG.
114 - The environment variable "LTTNG_UST_REGISTER_TIMEOUT" can be used to
115 specify how long the applications should wait for sessiond
116 "registration done" command before proceeding to execute the main
117 program. The default is 3000ms (3 seconds). The timeout value is
118 specified in milliseconds. The value 0 means "don't wait". The value
119 -1 means "wait forever". Setting this environment variable to 0 is
120 recommended for applications with time constraints on the process
123 - The compilation flag "-DLTTNG_UST_DEBUG_VALGRIND" should be enabled
124 at build time to allow liblttng-ust to be used with valgrind
125 (side-effect: disables per-cpu buffering).
130 Use babeltrace for viewing traces generated by LTTng UST 2.0.
131 See http://lttng.org for download.
136 Maintainer: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
137 Mailing list: lttng-dev@lists.lttng.org
142 This package contains the following elements.
145 The actual userspace tracing library that must be linked to the
146 instrumented programs.
149 The public header files that will be installed on the system.
152 Various test programs
154 - liblttng-ust-libc-wrapper
155 An example library that can be LD_PRELOAD'ed to instrument some
156 calls to libc (currently malloc() and free()) in any program without
157 need to recompile it.
160 A library that is LD_PRELOAD'ed, and that hijacks calls to several system
161 calls in order to trace across these calls. It _has_ to be LD_PRELOAD'ed
162 in order to hijack calls. In contrast, libust may be linked at build time.
165 A library to control tracing in other processes. Used by lttng-tools.
168 A static library shared between libust and lttng-tools, that
169 provides functions that allow these components to communicate together.
172 The ring buffer implementation used within LTTng-UST.
175 An asynchronous signal-safe version of snprintf.
178 A simple library that uses JNI to allow tracing in java programs.
179 See liblttng-ust-java/README for build instructions.