Documentation: fix manpage typo

[lttng-ust.git] / doc / man / lttng-ust.3

diff --git a/doc/man/lttng-ust.3 b/doc/man/lttng-ust.3
index 7dae8b538d8d4161e57f54bee9e5a872815e6f02..4adef5b942715f16a9ebba341b1ee52a81eccb93 100644 (file)
--- a/doc/man/lttng-ust.3
+++ b/doc/man/lttng-ust.3
@@ -48,6 +48,41 @@ whereas tracepoint.h is meant for thorough instrumentation of a code
 base to be integrated with an upstream project.
 .PP
 
 base to be integrated with an upstream project.
 .PP
 

+.SH "USAGE WITH TRACELOG"
+.PP
+If you want to migrate existing logging (info, errors, ...)
+to LTTng UST, you can use the tracelog() interface.
+To do it, in a nutshell:
+
+1) #include <lttng/tracelog.h>
+
+2) /* in your code, use like a printf, with extra loglevel info. */
+   tracelog(TRACE_INFO, "Message with integer %d", 1234);
+
+3) Link your program against liblttng-ust.so.
+
+4) Enable UST events when tracing with the following sequence of commands
+   from lttng-tools:
+
+   lttng create
+   lttng enable-event -u "lttng_ust_tracelog:*"
+   lttng start
+   [... run your program ...]
+   lttng stop
+   lttng view
+
+That's it!
+
+You can replace the enable-event line above with a selection of
+loglevels, e.g.:
+
+   lttng enable-event -u -a --loglevel TRACE_INFO
+
+Which will gather all events from TRACE_INFO and more important
+loglevels.
+
+.PP
+

 .SH "USAGE WITH TRACEPOINT"
 .PP
 The simple way to generate the lttng-ust tracepoint probes is to use the
 .SH "USAGE WITH TRACEPOINT"
 .PP
 The simple way to generate the lttng-ust tracepoint probes is to use the


@@ -189,6 +224,17 @@ TRACEPOINT_EVENT(
                 */
                ctf_float(float, floatfield, floatarg)
                ctf_float(double, doublefield, doublearg)
                 */
                ctf_float(float, floatfield, floatarg)
                ctf_float(double, doublefield, doublearg)

+
+               /*
+                * ctf_enum: a field using a previously declared
+                * enumeration args: (provider, enum name, container
+                * type, field name, argument expression). The
+                * enumeration itself and its values must have been
+                * defined previously with the TRACEPOINT_ENUM macro,
+                * described below.
+                */
+               ctf_enum(sample_component, enumeration_name, int,
+                             enumfield, enumarg)

        )
 )
 
        )
 )
 


@@ -196,6 +242,49 @@ There can be an arbitrary number of tracepoint providers within an
 application, but they must each have their own provider name. Duplicate
 provider names are not allowed.
 
 application, but they must each have their own provider name. Duplicate
 provider names are not allowed.
 

+The CTF specification also supports enumerations that can be declared
+inside a tracepoint provider and used as fields in the tracepoint. This
+shows how to specify enumerations and what they can be used for:
+
+The enumeration is a mapping between an integer, or a range of integers, and a
+string. It can be used to have a more compact trace in cases where the possible
+values for a field are limited:
+
+TRACEPOINT_ENUM(
+       /*
+        * The provider name, as described in the TRACEPOINT_EVENT macro.
+        */
+       sample_component,
+
+       /*
+        * The name of this enumeration, that will be used when using this
+        * global type in tracepoint fields.
+        */
+       enumeration_name,
+
+       /*
+        * TP_ENUM_VALUES describe the values of this enumeration and what they
+        * map to.
+        */
+       TP_ENUM_VALUES(
+               /*
+                * Maps an integer with this string value. By default, enumerations
+                * start at 0 and increment 1 for each entry.
+                */
+               ctf_enum_value(string_value)
+
+               /*
+                * Maps the string value to integers in the range 'start' to 'end'
+                * inclusively. If 'start' == 'end', then the string is mapped to
+                * a specific value.
+                * Enumeration ranges may overlap, but the behavior is
+                * implementation-defined, each trace reader will handle overlapping
+                * as it wishes.
+                */
+               ctf_enum_range(start, end, string_value)
+       )
+)
+

 .fi
 
 .SH "ASSIGNING LOGLEVEL TO EVENTS"
 .fi
 
 .SH "ASSIGNING LOGLEVEL TO EVENTS"


@@ -462,6 +551,18 @@ startup time.
 .IP "LTTNG_UST_WITHOUT_BADDR_STATEDUMP"
 Prevent liblttng-ust to perform a base-address statedump on session-enable.
 .PP
 .IP "LTTNG_UST_WITHOUT_BADDR_STATEDUMP"
 Prevent liblttng-ust to perform a base-address statedump on session-enable.
 .PP

+.IP "LTTNG_UST_GETCPU_PLUGIN"
+Used by the getcpu override plugin system. The environment variable
+provides the path to the shared object which will act as the getcpu override
+plugin. An example can be found in the lttng-ust documentation under
+examples/getcpu-override .
+.PP
+.IP "LTTNG_UST_CLOCK_PLUGIN"
+Used by the clock override plugin system. The environment variable
+provides the path to the shared object which will act as the clock override
+plugin. An example can be found in the lttng-ust documentation under
+doc/examples/clock-override .
+.PP

 
 .SH "SEE ALSO"
 
 
 .SH "SEE ALSO"