[gstreamer-bugs] [Bug 503592] gstpad.c does many ref/unref of peer pad in dataflow

[GStreamer (bugzilla.gnome.org)]

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  GStreamer | gstreamer (core) | Ver: HEAD CVS

Wim Taymans changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |wim.taymans at gmail.com




------- Comment #4 from Wim Taymans  2007-12-14 15:35 UTC -------
Not very practical, the unref happens at an undefined time and can keep the
sinkpad lingering on for as long as the srcpad is alive.

Just as a brain dump:

_pad_push (pad, buffer)
{
  LOCK (pad)
  peer = pad->peer;
  if (!peer)
    goto no_peer;
  chain_func = pad->peer_chain;
  if (chain_func != peer->chain)
    pad->peer_chain = chain_func;
  GST_STREAM_LOCK (peer);
  UNLOCK (pad)

  res = chain_func (peer); 

  GST_STREAM_UNLOCK (peer);

  return res;

no_peer:
  {
    UNLOCK (pad);
    return NOT_LINKED;
  }
}

This example uses a nested lock, there is no way the pad can get unlinked when
the pad lock is taken and we can be sure that the pad is not unreffed when we
have the stream_lock. Not sure this is correct...


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