Commit 3c96529c authored by Steven Rostedt (VMware)'s avatar Steven Rostedt (VMware)
Browse files

tracing: Add __find_event_file() to find event files without restrictions 



By adding the function __find_event_file() that can search for files without
restrictions, such as if the event associated with the file has a reg
function, or if it has the "ignore" flag set, the files that are associated
to ftrace internal events (like trace_marker and function events) can be
found and used.

find_event_file() still returns a "filtered" file, as most callers need a
valid trace event file. One created by the trace_events.h macros and not one
created for parsing ftrace specific events.

Reviewed-by: default avatarNamhyung Kim <namhyung@kernel.org>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent c94e45bc

kernel/trace/trace.h

+3 −0
Original line number Diff line number Diff line
@@ -1454,6 +1454,9 @@ extern void trace_event_enable_tgid_record(bool enable); 
extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);

extern int event_trace_del_tracer(struct trace_array *tr);



extern struct trace_event_file *__find_event_file(struct trace_array *tr,

						  const char *system,

						  const char *event);

extern struct trace_event_file *find_event_file(struct trace_array *tr,

						const char *system,

						const char *event);

kernel/trace/trace_events.c

+17 −5
Original line number Diff line number Diff line
@@ -2473,8 +2473,9 @@ __trace_add_event_dirs(struct trace_array *tr) 
	}

}



/* Returns any file that matches the system and event */

struct trace_event_file *

find_event_file(struct trace_array *tr, const char *system,  const char *event)

__find_event_file(struct trace_array *tr, const char *system, const char *event)

{

	struct trace_event_file *file;

	struct trace_event_call *call;
@@ -2485,10 +2486,7 @@ find_event_file(struct trace_array *tr, const char *system, const char *event) 
		call = file->event_call;

		name = trace_event_name(call);



		if (!name || !call->class || !call->class->reg)

			continue;



		if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)

		if (!name || !call->class)

			continue;



		if (strcmp(event, name) == 0 &&
@@ -2498,6 +2496,20 @@ find_event_file(struct trace_array *tr, const char *system, const char *event) 
	return NULL;

}



/* Returns valid trace event files that match system and event */

struct trace_event_file *

find_event_file(struct trace_array *tr, const char *system, const char *event)

{

	struct trace_event_file *file;



	file = __find_event_file(tr, system, event);

	if (!file || !file->event_call->class->reg ||

	    file->event_call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)

		return NULL;



	return file;

}



#ifdef CONFIG_DYNAMIC_FTRACE



/* Avoid typos */

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