[74/80] tracing: fix event_subsystem ref counting

From: Greg KH
Date: Wed Dec 07 2011 - 11:53:25 EST


3.0-stable review patch. If anyone has any objections, please let me know.

------------------

From: Ilya Dryomov <idryomov@xxxxxxxxx>

commit cb59974742aea24adf6637eb0c4b8e7b48bca6fb upstream.

Fix a bug introduced by e9dbfae5, which prevents event_subsystem from
ever being released.

Ref_count was added to keep track of subsystem users, not for counting
events. Subsystem is created with ref_count = 1, so there is no need to
increment it for every event, we have nr_events for that. Fix this by
touching ref_count only when we actually have a new user -
subsystem_open().

Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
Link: http://lkml.kernel.org/r/1320052062-7846-1-git-send-email-idryomov@xxxxxxxxx
Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
kernel/trace/trace_events.c | 1 -
1 file changed, 1 deletion(-)

--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1096,7 +1096,6 @@ event_subsystem_dir(const char *name, st
/* First see if we did not already create this dir */
list_for_each_entry(system, &event_subsystems, list) {
if (strcmp(system->name, name) == 0) {
- __get_system(system);
system->nr_events++;
return system->entry;
}


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/