[PATCH 3/4] trace: make trace_get_fields() global

From: Cong Wang
Date: Sat May 25 2019 - 13:01:30 EST


trace_get_fields() is the only way to read tracepoint fields at
run time, as their fields are defined at compile-time with macros.
Make this function visible to all users and it will be used by
trace event injection code to calculate the size of a tracepoint
entry.

Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Cong Wang <xiyou.wangcong@xxxxxxxxx>
---
include/linux/trace_events.h | 8 ++++++++
kernel/trace/trace_events.c | 8 --------
2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index 5c6f2a6c8cd2..5150436783e8 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -318,6 +318,14 @@ trace_event_name(struct trace_event_call *call)
return call->name;
}

+static inline struct list_head *
+trace_get_fields(struct trace_event_call *event_call)
+{
+ if (!event_call->class->get_fields)
+ return &event_call->class->fields;
+ return event_call->class->get_fields(event_call);
+}
+
struct trace_array;
struct trace_subsystem_dir;

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 0ce3db67f556..98df044d34ce 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -70,14 +70,6 @@ static int system_refcount_dec(struct event_subsystem *system)
#define while_for_each_event_file() \
}

-static struct list_head *
-trace_get_fields(struct trace_event_call *event_call)
-{
- if (!event_call->class->get_fields)
- return &event_call->class->fields;
- return event_call->class->get_fields(event_call);
-}
-
static struct ftrace_event_field *
__find_event_field(struct list_head *head, char *name)
{
--
2.21.0