-LTTNG USERSPACE TRACER
+LTTNG USERSPACE TRACER (LTTng-UST)
+----------------------------
-NOTE: THIS LIBRARY HAS NOT BEEN RELEASED YET BECAUSE ALTOUGH IT IS LICENCED AS
-LGPL, IT CAN ONLY BE USED AS GPL BECAUSE IT DEPENDS ON GPL LIBRARIES. IT WILL BE
-RELEASED AS SOON AS THESE ISSUES ARE RESOLVED.
+UST web site: http://lttng.org
-Dependencies:
+Updated versions of this package may be found at:
-- liburcu-pmf
- Userspace RCU library, pmf patches.
- http://git.dorsal.polymtl.ca
+ * Releases: http://lttng.org/download
+ * GitWeb: http://git.lttng.org (project: lttng-ust)
+ * Git: git://git.lttng.org/lttng-ust.git
-- libkcompat
- Linux kernel userspace compatibility library.
- http://git.dorsal.polymtl.ca
-Package contents:
+PREREQUISITES:
-- libust
- The actual userspace tracing library that must be linked to the
- instrumented programs.
+ - liburcu
+ Userspace RCU library, by Mathieu Desnoyers and Paul E. McKenney
-- ust
- A program to control the tracing of userspace applications. It can list
- markers, start the tracing, stop the tracing, enable/disable markers, etc.
+ -> This release depends on liburcu v0.7.2
-- ustd
- The daemon that collects trace data and writes it to the disk.
+ * Debian/Ubuntu package: liburcu-dev
+ * Website: http://lttng.org/urcu
+ * Releases: http://lttng.org/files/urcu
+ * GitWeb: http://lttng.org/cgi-bin/gitweb.cgi?p=userspace-rcu.git;a=summary
+ * Git: git://lttng.org/userspace-rcu.git
-- Documentation
+For developers using the git tree:
-- hello
- An example application that uses the userspace tracer.
+This source tree is based on the autotools suite from GNU to simplify
+portability. Here are some things you should have on your system in order to
+compile the git repository tree :
-- libmallocwrap
- An example library that can be LD_PRELOAD'ed to instrument calls to malloc()
- in any program without need to recompile it.
+- GNU autotools (automake >=1.10, autoconf >=2.50, autoheader >=2.50)
+ (make sure your system wide "automake" points to a recent version!)
+- GNU Libtool >=2.2
+ (for more information, go to http://www.gnu.org/software/autoconf/)
+- Perl (optional)
+ Needed for make check and tests.
+
+If you get the tree from the repository, you will need to use the "bootstrap"
+script in the root of the tree. It calls all the GNU tools needed to prepare the
+tree configuration.
+
+
+INSTALLATION INSTRUCTIONS:
+
+ - Download, compile and install liburcu.
+ - In this package's tree, run ./configure.
+ - Run make.
+ - Run make install.
+ - Run ldconfig.
+
+ If compiling from the git repository, run ./bootstrap before running
+ the configure script, to generate it.
+
+ Note that configure sets '/usr/local' as the default prefix for files it
+ installs. However, this path is not part of most distributions' default
+ library path which will cause builds depending on liblttng-ust to fail unless
+ '-L/usr/local/lib' is added to LDFLAGS. You may provide a custom prefix to
+ configure by using the --prefix switch.
+
+USAGE:
+
+ - Create an instrumentation header following the tracepoint examples.
+ See lttng/tracepoint.h, and examples.
+
+ There are 2 ways to compile the Tracepoint Provider with the
+ application: either statically or dynamically. Please follow
+ carefully:
+
+ 1.1) Compile the Tracepoint provider with the application, either
+ directly or through a static library (.a):
+ - Into exactly one object of your application: define
+ "TRACEPOINT_DEFINE" and include the tracepoint provider.
+ - Use "-I." for the compilation unit containing the tracepoint
+ provider include (e.g. tp.c).
+ - Link application with "-ldl" on Linux, with "-lc" on BSD.
+ - If building the provider directly into the application,
+ link the application with "-llttng-ust".
+ - If building a static library for the provider, link the static
+ library with "-llttng-ust".
+ - Include the tracepoint provider header into all C files using
+ the provider.
+ - Examples:
+ - doc/examples/easy-ust/ sample.c sample_component_provider.h
+ tp.c Makefile
+ - doc/examples/hello-static-lib/ hello.c tp.c ust_test_hello.h
+ Makefile
+
+ 2) Compile the Tracepoint Provider separately from the application,
+ using dynamic linking:
+ - Into exactly one object of your application: define
+ "TRACEPOINT_DEFINE" _and_ also define
+ "TRACEPOINT_PROBE_DYNAMIC_LINKAGE", then include the tracepoint
+ provider header.
+ - Include the tracepoint provider header into all instrumented C
+ files that use the provider.
+ - Compile the tracepoint provider with "-I.".
+ - Link the tracepoint provider with "-llttng-ust".
+ - Link application with "-ldl" on Linux, "-lc" on BSD.
+ - Set a LD_PRELOAD environment to preload the tracepoint provider
+ shared object before starting the application when tracing is
+ needed. Another way is to dlopen the tracepoint probe when needed
+ by the application.
+ - Example:
+ - doc/examples/demo demo.c tp*.c ust_tests_demo*.h demo-trace Makefile
+
+ - Note about dlclose() usage: it is not safe to use dlclose on a
+ provider shared object that is being actively used for tracing due
+ to a lack of reference counting from lttng-ust to the used shared
+ object.
+ - Enable instrumentation and control tracing with the "lttng" command
+ from lttng-tools. See lttng-tools doc/quickstart.txt.
+ - Note for C++ support: since LTTng-UST 2.3, both tracepoints and
+ tracepoint probes can be compiled in C++. To compile tracepoint probes
+ in C++, you need g++ >= 4.7 or Clang.
+
+
+ENVIRONMENT VARIABLES:
+
+ - liblttng-ust debug can be activated by setting the environment variable
+ "LTTNG_UST_DEBUG" when launching the application. It can also be enabled
+ at compile-time by compiling libust with -DLTTNG_UST_DEBUG.
+
+ - The environment variable "LTTNG_UST_REGISTER_TIMEOUT" can be used to
+ specify how long the applications should wait for sessiond
+ "registration done" command before proceeding to execute the main
+ program. The default is 3000ms (3 seconds). The timeout value is
+ specified in milliseconds. The value 0 means "don't wait". The value
+ -1 means "wait forever". Setting this environment variable to 0 is
+ recommended for applications with time constraints on the process
+ startup time.
+
+ - The compilation flag "-DLTTNG_UST_DEBUG_VALGRIND" should be enabled
+ at build time to allow liblttng-ust to be used with valgrind
+ (side-effect: disables per-cpu buffering).
+
+
+TRACE VIEWER:
+
+ Use babeltrace for viewing traces generated by LTTng UST 2.x.
+ See http://lttng.org for download.
+
+
+CONTACT:
+
+ Maintainer: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ Mailing list: lttng-dev@lists.lttng.org
+
+
+PACKAGE CONTENTS:
+
+ This package contains the following elements.
+
+ - liblttng-ust
+ The actual userspace tracing library that must be linked to the
+ instrumented programs.
+
+ - include
+ The public header files that will be installed on the system.
+
+ - tests
+ Various test programs
+
+ - liblttng-ust-libc-wrapper
+ An example library that can be LD_PRELOAD'ed to instrument some
+ calls to libc (currently malloc() and free()) in any program without
+ need to recompile it.
+
+ - liblttng-ust-fork
+ A library that is LD_PRELOAD'ed, and that hijacks calls to several system
+ calls in order to trace across these calls. It _has_ to be LD_PRELOAD'ed
+ in order to hijack calls. In contrast, libust may be linked at build time.
+
+ - liblttng-ust-ctl
+ A library to control tracing in other processes. Used by lttng-tools.
+
+ - liblttng-ust-comm
+ A static library shared between libust and lttng-tools, that
+ provides functions that allow these components to communicate together.
+
+ - libringbuffer
+ The ring buffer implementation used within LTTng-UST.
+
+ - snprintf
+ An asynchronous signal-safe version of snprintf.
+
+ - liblttng-ust-java
+ A simple library that uses JNI to allow tracing in java programs.
+ See liblttng-ust-java/README for build instructions.