tracing/events: add support for modules to TRACE_EVENT

Impact: allow modules to add TRACE_EVENTS on load

This patch adds the final hooks to allow modules to use the TRACE_EVENT
macro. A notifier and a data structure are used to link the TRACE_EVENTs
defined in the module to connect them with the ftrace event tracing system.

It also adds the necessary automated clean ups to the trace events when a
module is removed.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/module.h b/include/linux/module.h
index 627ac082e2a6..6155fa44168b 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -337,6 +337,10 @@ struct module
         const char **trace_bprintk_fmt_start;
         unsigned int num_trace_bprintk_fmt;
 #endif
+#ifdef CONFIG_EVENT_TRACING
+        struct ftrace_event_call *trace_events;
+        unsigned int num_trace_events;
+#endif
 
 #ifdef CONFIG_MODULE_UNLOAD
         /* What modules depend on me? */