X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=doc%2Fman%2Flttng-ust.3;h=5be3cfaa081a669cb8d9b9e990117dd63f9bc735;hb=efbad5cc87395d00fa1d578ae211aee431fa3b4a;hp=818ef103ae407498c133ba9e64580595f3b47254;hpb=94c9c48da8ea6424c01d17409cc6788f7ea70450;p=lttng-ust.git

diff --git a/doc/man/lttng-ust.3 b/doc/man/lttng-ust.3
index 818ef103..5be3cfaa 100644
--- a/doc/man/lttng-ust.3
+++ b/doc/man/lttng-ust.3
@@ -1,7 +1,7 @@
 .TH "LTTNG-UST" "3" "February 16, 2012" "" ""
 
 .SH "NAME"
-lttng-ust \(em Linux Trace Toolkit Next Generation User-Space Tracer
+lttng-ust \(em Linux Trace Toolkit Next Generation User-Space Tracer 2.x
 
 .SH "SYNOPSIS"
 
@@ -123,6 +123,10 @@ TRACEPOINT_EVENT(
 		 * ctf_sequence: a dynamically-sized array.
 		 * args: (type, field name, argument expression,
 		 *	type of length expression, length expression)
+		 * The "type of length expression" needs to be an
+		 * unsigned type. As a reminder, "unsigned char" should
+		 * be preferred to "char", since the signedness of
+		 * "char" is implementation-defined.
 		 */ 
 		ctf_sequence(char, seqfield1, text,
 			     size_t, textlen)
@@ -238,6 +242,10 @@ For instance, add within a function:
 As a call to the tracepoint. It will only be activated when requested by
 lttng(1) through lttng-sessiond(8).
 
+Even though LTTng-UST supports tracepoint() call site duplicates having
+the same provider and event name, it is recommended to use a
+provider event name pair only once within the source code to help
+mapping events back to their call sites when analyzing the trace.
 .fi
 
 .SH "BUILDING/LINKING THE TRACEPOINT PROVIDER"
@@ -261,7 +269,7 @@ carefully:
     - Include the tracepoint provider header into all C files using
       the provider.
     - Example:
-        tests/hello/  hello.c tp.c ust_tests_hello.h Makefile.example
+      - tests/hello/  hello.c tp.c ust_tests_hello.h Makefile.example
 
   2) Compile the Tracepoint Provider separately from the application,
      using dynamic linking:
@@ -276,15 +284,15 @@ carefully:
     - Link application with "\-ldl".
     - Set a LD_PRELOAD environment to preload the tracepoint provider
       shared object before starting the application when tracing is
-      needed.
+      needed. Another way is to dlopen the tracepoint probe when needed
+      by the application.
     - Example:
-      - tests/demo/   demo.c  tp*.c ust_tests_demo*.h demo-trace
+      - doc/examples/demo   demo.c  tp*.c ust_tests_demo*.h demo-trace
 
-  - Note about dlopen() usage: due to locking side-effects due to the
-    way libc lazily resolves Thread-Local Storage (TLS) symbols when a
-    library is dlopen'd, linking the tracepoint probe or liblttng-ust
-    with dlopen() is discouraged. They should be linked with the
-    application using "\-llibname" or loaded with LD_PRELOAD.
+  - 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: although an application instrumented with
@@ -356,12 +364,13 @@ startup time.
 .SH "SEE ALSO"
 
 .PP
-lttng-gen-tp(1), lttng(1), babeltrace(1), lttng-sessiond(8)
+lttng-gen-tp(1), lttng(1), babeltrace(1), lttng-ust-cyg-profile(3),
+lttng-sessiond(8)
 .PP
 .SH "BUGS"
 
 .PP
-No knows bugs at this point.
+No known bugs at this point.
 
 If you encounter any issues or usability problem, please report it on
 our mailing list <lttng-dev@lists.lttng.org> to help improve this