[tip:perf/core] tracing: fix event_subsystem ref counting

[tip-bot for Ilya Dryomov <idryomov@gmail.com>]

Commit-ID:  d631097577f6fe027f4903f62eabced6445d19bf
Gitweb:     http://git.kernel.org/tip/d631097577f6fe027f4903f62eabced6445d19bf
Author:     Ilya Dryomov <idryomov@gmail.com>
AuthorDate: Mon, 31 Oct 2011 11:07:42 +0200
Committer:  Steven Rostedt <rostedt@goodmis.org>
CommitDate: Mon, 31 Oct 2011 13:59:23 -0400

tracing: fix event_subsystem ref counting

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().

Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Link: http://lkml.kernel.org/r/1320052062-7846-1-git-send-email-idryomov@gmail.com
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/trace_events.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 581876f..c212a7f 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1078,7 +1078,6 @@ event_subsystem_dir(const char *name, struct dentry *d_events)
 	/* 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;
 		}