+++ /dev/null
-.TH "LTTNG-UST-CYG-PROFILE" "3" "March 26, 2013" "" ""
-.SH "NAME"
-lttng-ust-cyg-profile \(em LTTng UST 2.x Function Tracing
-.SH "SYNOPSIS"
-Compile the application source code with option \fB-finstrument-functions\fP
-and launch your application either with:
-.TP
-\fBLD_PRELOAD=liblttng-ust-cyg-profile-fast.so\fP appname
-.PP
-or (to use verbose function tracing)
-.TP
-\fBLD_PRELOAD=liblttng-ust-cyg-profile.so\fP appname
-.PP
-All events emitted for function tracing are provided on loglevel
-TRACE_DEBUG_FUNCTION. The following command can be used to add
-function tracing events in your trace session:
-.TP
-.B lttng enable-event -u -a --loglevel-only TRACE_DEBUG_FUNCTION
-.SH "DESCRIPTION"
-For compilers that provide code generation option
-\fB-finstrument-functions\fP (e.g. GCC and LLVM/Clang) LTTng-UST provides
-shared libraries that allow users to trace the function flow of their
-applications.
-
-Function tracing comes in two flavors (each providing different trade-offs):
-.IP liblttng-ust-cyg-profile-fast.so
-This is a lightweight variant that should only be used where it can be
-guaranteed that the complete event stream is recorded without any missing
-events. Any kind of duplicate information is left out.
-
-At each function entry the address of the called function is recored as
-lttng_ust_cyg_profile_fast:func_entry. Function exit is recorded as
-lttng_ust_cyg_profile_fast:func_exit (without any field data).
-
-.IP liblttng-ust-cyg-profile.so
-This is a more robust variant which also works for use-cases where events
-might get discarded or not recorded from application startup. In these cases
-the trace analyzer needs extra information to be able to reconstruct the
-program flow.
-
-For each function entry and exit the address of the called function and the
-call site address are recorded as lttng_ust_cyg_profile:func_entry and
-lttng_ust_cyg_profile:func_exit.
-.SH "USAGE"
-To use function tracing you need to make sure the sources of your application
-are compiled with \-finstrument\-functions. It might be necessary to limit
-the number of source files where this option is used to prevent excessive
-amount of trace data to be generated during run time. Usually there are
-additional compiler flags that allow you to specify more fine grained selection
-of function instrumentation.
-
-For each instrumented function the executable will contain calls to profiling
-function hooks (after function entry and just before function exit).
-
-By preloading (LD_PRELOAD) one of the provided shared libraries, these
-profiling hooks get defined to emit LTTng events (as described above).
-
-Using this feature can result in massive amount trace data to be generated
-by the instrumented application. Application runtime is also considerably
-affected. Be careful on systems with limited resources.
-.SH "SEE ALSO"
-lttng-ust(3), lttng(1), gcc(1), ld.so(8)
-.SH "BUGS"
-If you encounter any issues or usability problem, please report it on
-our mailing list <lttng-dev@lists.lttng.org> to help improve this
-project.
-.SH "CREDITS"
-liblttng-ust is distributed under the GNU Lesser General Public License
-version 2.1. The headers are distributed under the MIT license.
-
-See http://lttng.org for more information on the LTTng project.
-
-Mailing list for support and development: <lttng-dev@lists.lttng.org>.
-
-You can find us on IRC server irc.oftc.net (OFTC) in #lttng.
-.SH "AUTHORS"
-liblttng-ust was originally written by Mathieu Desnoyers, with additional
-contributions from various other people. It is currently maintained by
-Mathieu Desnoyers <mathieu.desnoyers@efficios.com>.
projects / lttng-ust.git / blobdiff