Implement loglevels as event and wildcard attributes

[lttng-ust.git] / include / lttng / ust-tracepoint-event.h

diff --git a/include/lttng/ust-tracepoint-event.h b/include/lttng/ust-tracepoint-event.h
index 6983ef1691d39949e3a72fe11cedf7030cf1d050..dbd0485565cfd18e2d920811d5dbbb3cb4c79f93 100644 (file)
--- a/include/lttng/ust-tracepoint-event.h
+++ b/include/lttng/ust-tracepoint-event.h
@@ -117,6 +117,25 @@ void _TP_COMBINE_TOKENS(__tracepoint_provider_check_, TRACEPOINT_PROVIDER)(void)
 #include TRACEPOINT_INCLUDE
 }
 
+/*
+ * Stage 0.1 of tracepoint event generation.
+ *
+ * Check that each TRACEPOINT_EVENT provider:name does not exceed the
+ * tracepoint name length limit.
+ */
+
+/* Reset all macros within TRACEPOINT_EVENT */
+#include <lttng/ust-tracepoint-event-reset.h>
+
+#undef TRACEPOINT_EVENT_INSTANCE
+#define TRACEPOINT_EVENT_INSTANCE(_provider, _template, _name, _args)  \
+static const char                                                      \
+       __tp_name_len_check##_provider##___##_name[LTTNG_UST_SYM_NAME_LEN] \
+       __attribute__((unused)) =                                       \
+               #_provider ":" #_name;
+
+#include TRACEPOINT_INCLUDE
+
 /*
  * Stage 1 of tracepoint event generation.
  *
@@ -215,41 +234,6 @@ static void __event_probe__##_provider##___##_name(_TP_ARGS_DATA_PROTO(_args));
 /*
  * Stage 3 of tracepoint event generation.
  *
- * Create an array of events.
- */
-
-/* Reset all macros within TRACEPOINT_EVENT */
-#include <lttng/ust-tracepoint-event-reset.h>
-
-#undef TRACEPOINT_EVENT_INSTANCE
-#define TRACEPOINT_EVENT_INSTANCE(_provider, _template, _name, _args)         \
-               {                                                              \
-                       .fields = __event_fields___##_provider##___##_template,\
-                       .name = #_provider ":" #_name,                         \
-                       .probe_callback = (void *) &__event_probe__##_provider##___##_template,\
-                       .nr_fields = _TP_ARRAY_SIZE(__event_fields___##_provider##___##_template), \
-               },
-
-static const struct lttng_event_desc _TP_COMBINE_TOKENS(__event_desc___, TRACEPOINT_PROVIDER)[] = {
-#include TRACEPOINT_INCLUDE
-};
-
-
-/*
- * Stage 4 of tracepoint event generation.
- *
- * Create a toplevel descriptor for the whole probe.
- */
-
-/* non-const because list head will be modified when registered. */
-static struct lttng_probe_desc _TP_COMBINE_TOKENS(__probe_desc___, TRACEPOINT_PROVIDER) = {
-       .event_desc = _TP_COMBINE_TOKENS(__event_desc___, TRACEPOINT_PROVIDER),
-       .nr_events = _TP_ARRAY_SIZE(_TP_COMBINE_TOKENS(__event_desc___, TRACEPOINT_PROVIDER)),
-};
-
-/*
- * Stage 5 of tracepoint event generation.
- *
  * Create static inline function that calculates event size.
  */
 
@@ -307,7 +291,7 @@ static inline size_t __event_get_size__##_provider##___##_name(size_t *__dynamic
 #include TRACEPOINT_INCLUDE
 
 /*
- * Stage 6 of tracepoint event generation.
+ * Stage 4 of tracepoint event generation.
  *
  * Create static inline function that calculates event payload alignment.
  */
@@ -356,7 +340,7 @@ size_t __event_get_align__##_provider##___##_name(_TP_ARGS_PROTO(_args))      \
 
 
 /*
- * Stage 7 of tracepoint event generation.
+ * Stage 5 of tracepoint event generation.
  *
  * Create the probe function. This function calls event size calculation
  * and writes event data into the buffer.
@@ -449,9 +433,86 @@ static void __event_probe__##_provider##___##_name(_TP_ARGS_DATA_PROTO(_args))\
 
 #undef __get_dynamic_len
 
+/*
+ * Stage 6 of tracepoint event generation.
+ *
+ * Tracepoint loglevel mapping definition generation. We generate a
+ * symbol for each mapping for a provider/event to ensure at most a 1 to
+ * 1 mapping between events and loglevels. If the symbol is repeated,
+ * the compiler will complain.
+ */
+
+/* Reset all macros within TRACEPOINT_EVENT */
+#include <lttng/ust-tracepoint-event-reset.h>
+
+#undef TRACEPOINT_LOGLEVEL
+#define TRACEPOINT_LOGLEVEL(__provider, __name, __loglevel)               \
+static const int _loglevel_value___##__provider##___##__name = __loglevel; \
+static const int *_loglevel___##__provider##___##__name =                 \
+               &_loglevel_value___##__provider##___##__name;
+
+#include TRACEPOINT_INCLUDE
+
+/*
+ * Stage 7.1 of tracepoint event generation.
+ *
+ * Create events description structures. We use a weakref because
+ * loglevels are optional. If not declared, the event will point to the
+ * a loglevel that contains NULL.
+ */
+
+/* Reset all macros within TRACEPOINT_EVENT */
+#include <lttng/ust-tracepoint-event-reset.h>
+
+#undef TRACEPOINT_EVENT_INSTANCE
+#define TRACEPOINT_EVENT_INSTANCE(_provider, _template, _name, _args)         \
+static const int *                                                            \
+       __ref_loglevel___##_provider##___##_name                               \
+       __attribute__((weakref ("_loglevel___" #_provider "___" #_name)));     \
+const struct lttng_event_desc __event_desc___##_provider##_##_name = {        \
+       .fields = __event_fields___##_provider##___##_template,                \
+       .name = #_provider ":" #_name,                                         \
+       .probe_callback = (void *) &__event_probe__##_provider##___##_template,\
+       .nr_fields = _TP_ARRAY_SIZE(__event_fields___##_provider##___##_template), \
+       .loglevel = &__ref_loglevel___##_provider##___##_name,                 \
+};
+
+#include TRACEPOINT_INCLUDE
+
+/*
+ * Stage 7.2 of tracepoint event generation.
+ *
+ * Create array of events.
+ */
+
+/* Reset all macros within TRACEPOINT_EVENT */
+#include <lttng/ust-tracepoint-event-reset.h>
+
+#undef TRACEPOINT_EVENT_INSTANCE
+#define TRACEPOINT_EVENT_INSTANCE(_provider, _template, _name, _args)         \
+       &__event_desc___##_provider##_##_name,
+
+static const struct lttng_event_desc *_TP_COMBINE_TOKENS(__event_desc___, TRACEPOINT_PROVIDER)[] = {
+#include TRACEPOINT_INCLUDE
+};
+
+
 /*
  * Stage 8 of tracepoint event generation.
  *
+ * Create a toplevel descriptor for the whole probe.
+ */
+
+/* non-const because list head will be modified when registered. */
+static struct lttng_probe_desc _TP_COMBINE_TOKENS(__probe_desc___, TRACEPOINT_PROVIDER) = {
+       .provider = __tp_stringify(TRACEPOINT_PROVIDER),
+       .event_desc = _TP_COMBINE_TOKENS(__event_desc___, TRACEPOINT_PROVIDER),
+       .nr_events = _TP_ARRAY_SIZE(_TP_COMBINE_TOKENS(__event_desc___, TRACEPOINT_PROVIDER)),
+};
+
+/*
+ * Stage 9 of tracepoint event generation.
+ *
  * Register/unregister probes at module load/unload.
  */