[RFC][PATCH 03/10] tracing: Add an 'accessor' function to ftrace_event_field

[Tom Zanussi <tom.zanussi@linux.intel.com>]

For grabbing the contents of an event field from a trace record, it
would be useful to associate a field-specific accessor function with
an event field.  This defines an accessor prototype and adds an
accessor field to struct ftrace_event_field for that purpose.

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
---
 kernel/trace/trace.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index fed2ae0..7b48a3c 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1030,11 +1030,16 @@ static inline void trace_branch_disable(void)
 /* set ring buffers to default size if not already done so */
 int tracing_update_buffers(void);
 
+struct ftrace_event_field;
+
+typedef u64 (*ftrace_event_field_fn_t) (struct ftrace_event_field *field, void *event);
+
 struct ftrace_event_field {
 	struct list_head	link;
 	const char		*name;
 	const char		*type;
 	int			filter_type;
+	ftrace_event_field_fn_t	accessor;
 	int			offset;
 	int			size;
 	int			is_signed;
-- 
1.9.3