[Beignet] [PATCH V2] Fix event pthread_mutex_lock dead lock.

[Zhigang Gong]

This version LGTM, pushed, thanks.
On Wed, Aug 14, 2013 at 11:08:01AM +0800, Yang Rong wrote:
> In function cl_event_set_status, between pthread_mutex_lock and pthread_mutex_unlock
> will call cl_event_delete, which also require the same lock, cause deak lock.
> Unlock it before call cl_event_delete.
> 
> Signed-off-by: Yang Rong <rong.r.yang at intel.com>
> ---
>  src/cl_event.c |   21 +++++++++++++++++----
>  1 file changed, 17 insertions(+), 4 deletions(-)
> 
> diff --git a/src/cl_event.c b/src/cl_event.c
> index 48f24e5..e882c7c 100644
> --- a/src/cl_event.c
> +++ b/src/cl_event.c
> @@ -305,23 +305,36 @@ void cl_event_set_status(cl_event event, cl_int status)
>  
>    pthread_mutex_lock(&event->ctx->event_lock);
>    if(status >= event->status) {
> -   return;
> +    pthread_mutex_unlock(&event->ctx->event_lock);
> +    return;
> +  }
> +  if(event->status <= CL_COMPLETE) {
> +    event->status = status;    //have done enqueue before or doing in another thread
> +    pthread_mutex_unlock(&event->ctx->event_lock);
> +    return;
>    }
>  
>    if(status <= CL_COMPLETE) {
>      if(event->enqueue_cb) {
> +      cl_enqueue_handle(&event->enqueue_cb->data);
> +      event->status = status;  //Change the event status after enqueue and befor unlock
> +
> +      pthread_mutex_unlock(&event->ctx->event_lock);
>        for(i=0; i<event->enqueue_cb->num_events; i++)
>          cl_event_delete(event->enqueue_cb->wait_list[i]);
> +      pthread_mutex_lock(&event->ctx->event_lock);
>  
> -      cl_enqueue_handle(&event->enqueue_cb->data);
>        cl_free(event->enqueue_cb);
>        event->enqueue_cb = NULL;
>      }
> -    cl_event_delete(event);
>    }
> -  event->status = status;
> +  if(event->status >= status)  //maybe changed in other threads
> +    event->status = status;
>    pthread_mutex_unlock(&event->ctx->event_lock);
>  
> +  if(event->status <= CL_COMPLETE)
> +    cl_event_delete(event);
> +
>    /* Call user callback */
>    user_cb = event->user_cb;
>    while(user_cb) {
> -- 
> 1.7.10.4
> 
> _______________________________________________
> Beignet mailing list
> Beignet at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/beignet