[vlc-devel] [RFC PATCH 1/5] decoder: fix deadlock when deleting a paused decoder

[Rémi Denis-Courmont]

On Friday 06 November 2015 14:48:43 Thomas Guillem wrote:
> ---
>  src/input/decoder.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/src/input/decoder.c b/src/input/decoder.c
> index 5f7cc01..daf4479 100644
> --- a/src/input/decoder.c
> +++ b/src/input/decoder.c
> @@ -1829,9 +1829,13 @@ void input_DecoderDelete( decoder_t *p_dec )
> 
>      vlc_cancel( p_owner->thread );
> 
> +    vlc_fifo_Lock( p_owner->p_fifo );
> +    p_owner->paused = false;
> +    vlc_fifo_Signal( p_owner->p_fifo );
> +    vlc_fifo_Unlock( p_owner->p_fifo );
> +

The thread is already canceled by this point. If it ever waited on the FIFO 
condition variable, it would terminate. So this looks like a no-op to me.

In fact, I cannot reproduce any deadlock when stopping during pause.

>      /* Make sure we aren't paused/waiting/decoding anymore */
>      vlc_mutex_lock( &p_owner->lock );
> -    p_owner->paused = false;

This part seems correct.

>      p_owner->b_waiting = false;
>      p_owner->b_flushing = true;
>      vlc_cond_signal( &p_owner->wait_request );

-- 
Rémi Denis-Courmont
http://www.remlab.net/