Re: [PATCH] tracing: fix event_subsystem ref counting

[Steven Rostedt <rostedt@goodmis.org>]

On Mon, 2011-10-31 at 11:07 +0200, Ilya Dryomov wrote:
> 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().

Good catch, I'll pull this in.

Thanks!

-- Steve

> 
> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
> ---
>  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;
>  		}