+ * Tells if the event is enabled or not on the agent. While this can be
+ * implicitly tested as a boolean, it is in fact a reference count and
+ * the AGENT_EVENT_IS_ENABLED macro should be used to prevent accidental
+ * comparisons to non-zero literals (e.g. '1').
+ *
+ * Multiple triggers and events can map to the same agent event as it
+ * is merely a "filter" in front of a user space tracer enabler.
+ *
+ * This count is updated to ensure an event is only disabled when all
+ * matching enablers are disabled.