X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=include%2Fust%2Ftracepoint.h;h=e7c6b198bc464bde94990623df48912b4af51a68;hb=e9f37b4cb3e2485b949083307aadfc4bda56ce96;hp=d793e58ca8da5b2ca18f0179709255c4b1e5b788;hpb=6cdf29f8cd289d763fae461c618975fe43095e8b;p=lttng-ust.git

diff --git a/include/ust/tracepoint.h b/include/ust/tracepoint.h
index d793e58c..e7c6b198 100644
--- a/include/ust/tracepoint.h
+++ b/include/ust/tracepoint.h
@@ -170,9 +170,6 @@ int tracepoint_unregister_lib(struct tracepoint * const *tracepoints_start);
  * These weak symbols, the constructor, and destructor take care of
  * registering only _one_ instance of the tracepoints per shared-ojbect
  * (or for the whole main program).
- * The dummy tracepoint entry ensures that the start/stop pointers get
- * initialized by the linker when no tracepoints are present in a
- * shared-object (or main program).
  */
 extern struct tracepoint * const __start___tracepoints_ptrs[]
 	__attribute__((weak, visibility("hidden")));
@@ -235,6 +232,7 @@ static void __attribute__((destructor)) __tracepoints__destroy(void)
  *
  * Firstly, name your tracepoint via TRACEPOINT_EVENT(name,
  *
+ * The name should be a proper C99 identifier.
  * The "name" MUST follow these rules to ensure no namespace clash
  * occurs:
  *
@@ -330,6 +328,13 @@ static void __attribute__((destructor)) __tracepoints__destroy(void)
  *		ctf_integer(int, next_prio, next->prio)
  *	)
  * )
+ *
+ * Do _NOT_ add comma (,) nor semicolon (;) after the TRACEPOINT_EVENT
+ * declaration.
+ *
+ * The TRACEPOINT_SYSTEM must be defined when declaring a
+ * TRACEPOINT_EVENT. See ust/tracepoint-event.h for information about
+ * usage of other macros controlling TRACEPOINT_EVENT.
  */
 
 #define TRACEPOINT_EVENT(name, proto, args, fields)			\
@@ -351,4 +356,61 @@ static void __attribute__((destructor)) __tracepoints__destroy(void)
 
 #endif /* #ifndef TRACEPOINT_EVENT */
 
+#ifndef TRACEPOINT_LOGLEVEL
+
+/*
+ * Tracepoint Loglevel Declaration Facility
+ *
+ * This is a place-holder the tracepoint loglevel declaration,
+ * overridden by the tracer implementation.
+ *
+ * Typical use of these loglevels:
+ *
+ * 1) Declare the mapping between loglevel names and an integer values
+ *    within TRACEPOINT_LOGLEVEL_ENUM, using TP_LOGLEVEL for each tuple.
+ *    Do _NOT_ add comma (,) nor semicolon (;) between the
+ *    TRACEPOINT_LOGLEVEL_ENUM entries. Do _NOT_ add comma (,) nor
+ *    semicolon (;) after the TRACEPOINT_LOGLEVEL_ENUM declaration.  The
+ *    name should be a proper C99 identifier.
+ *
+ *      TRACEPOINT_LOGLEVEL_ENUM(
+ *              TP_LOGLEVEL( < loglevel_name >, < value > )
+ *              TP_LOGLEVEL( < loglevel_name >, < value > )
+ *              ...
+ *      )
+ *
+ *    e.g.:
+ *
+ *      TRACEPOINT_LOGLEVEL_ENUM(
+ *              TP_LOGLEVEL(LOG_EMERG,   0)
+ *              TP_LOGLEVEL(LOG_ALERT,   1)
+ *              TP_LOGLEVEL(LOG_CRIT,    2)
+ *              TP_LOGLEVEL(LOG_ERR,     3)
+ *              TP_LOGLEVEL(LOG_WARNING, 4)
+ *              TP_LOGLEVEL(LOG_NOTICE,  5)
+ *              TP_LOGLEVEL(LOG_INFO,    6)
+ *              TP_LOGLEVEL(LOG_DEBUG,   7)
+ *      )
+ *
+ * 2) Then, declare tracepoint loglevels for tracepoints. A
+ *    TRACEPOINT_EVENT should be declared prior to the the
+ *    TRACEPOINT_LOGLEVEL for a given tracepoint name. The first field
+ *    is the name of the tracepoint, the second field is the loglevel
+ *    name.
+ *
+ *      TRACEPOINT_LOGLEVEL(< [com_company_]project_[component_]event >,
+ *              < loglevel_name >)
+ *
+ * The TRACEPOINT_SYSTEM must be defined when declaring a
+ * TRACEPOINT_LOGLEVEL_ENUM and TRACEPOINT_LOGLEVEL. The tracepoint
+ * loglevel enumeration apply to the entire TRACEPOINT_SYSTEM. Only one
+ * tracepoint loglevel enumeration should be declared per tracepoint
+ * system.
+ */
+
+#define TRACEPOINT_LOGLEVEL_ENUM()
+#define TRACEPOINT_LOGLEVEL(name, loglevel)
+
+#endif /* #ifndef TRACEPOINT_LOGLEVEL */
+
 #endif /* _UST_TRACEPOINT_H */