+== Source Lookup (for LTTng-UST 2.8+) ==
+
+Starting with LTTng 2.8, the tracer can now provide enough information to
+associate trace events with their location in the original source code.
+
+To make use of this feature, first make sure your binaries are compiled with
+debug information (-g), so that the instruction pointers can be mapped to source
+code locations. This lookup is made using the ''addr2line'' command-line utility,
+which needs to be installed and on the '''$PATH''' of the system running Trace
+Compass. ''addr2line'' is available in most Linux distributions, Mac OS X, Windows using Cygwin and others.
+
+The following trace events need to be present in the trace:
+
+* lttng_ust_statedump:start
+* lttng_ust_statedump:end
+* lttng_ust_statedump:bin_info
+* lttng_ust_statedump:build_id
+
+as well as the following contexts:
+
+* vpid
+* ip
+
+For ease of use, you can simply enable all the UST events when setting up your
+session:
+
+ lttng enable-event -u -a
+ lttng add-context -u -t vpid -t ip
+
+Note that you can also create and configure your session using the [[#Control View | Control View]].
+
+If you want to track source locations in shared libraries loaded by the
+application, you also need to enable the "lttng_ust_dl:*" events, as well
+as preload the UST library providing them when running your program:
+
+ LD_PRELOAD=/path/to/liblttng-ust-dl.so ./myprogram
+
+If all the required information is present, then the ''Source Location'' column
+of the Event Table should be populated accordingly, and the ''Open Source Code''
+action should be available. Refer to the section [[#Event Source Lookup]] for
+more details.
+
+The ''Binary Location'' information should be present even if the original
+binaries are not available, since it only makes use of information found in the
+trace. A '''+''' denotes a relative address (i.e. an offset within the object
+itself), whereas a '''@''' denotes an absolute address, for
+non-position-independent objects.
+
+[[Image:images/sourceLookup/trace-with-debug-info.png]]
+
+''Example of a trace with debug info and corresponding Source Lookup information, showing a tracepoint originating from a shared library''
+
+=== Binary file location configuration ===
+
+To resolve addresses to function names and source code locations, the analysis
+makes use of the binary files (executables or shared libraries) present on the
+system. By default, it will look for the file paths as they are found in the
+trace, which means that it should work out-of-the-box if the trace was taken on
+the same machine that Trace Compass is running.
+
+It is possible to configure a ''root directory'' that will be used as a prefix
+for all file path resolutions. The button to open the configuration dialog is
+called '''Configure how addresses are mapped to function names''' and is
+currently located in the [[#Call Stack View]]. Note that the Call Stack View
+will also make use of this configuration to resolve its function names.
+
+[[Image:images/sourceLookup/symbol-mapping-config-ust28.png]]
+
+''The symbol configuration dialog for LTTng-UST 2.8+ traces''
+
+This can be useful if a trace was taken on a remote target, and an image of that
+target is available locally.
+
+If a binary file is being traced on a target, the paths in the trace will refer
+to the paths on the target. For example, if they are:
+
+* /usr/bin/program
+* /usr/lib/libsomething.so
+* /usr/local/lib/libcustom.so
+
+and an image of that target is copied locally on the system at
+''/home/user/project/image'', which means the binaries above end up at:
+
+* /home/user/project/image/usr/bin/program
+* /home/user/project/image/usr/lib/libsomething.so
+* /home/user/project/image/usr/local/lib/libcustom.so
+
+Then selecting the ''/home/user/project/image'' directory in the configuration
+dialog above will allow Trace Compass to read the debug symbols correctly.
+
+Note that this path prefix will apply to both binary file and source file
+locations, which may or may not be desirable.
+