hvirtual/cinelerra/mutex_bug

   1 VEdit::render checking out
   2 Cache::check_out 1
   3 Cache::check_out 2
   4                         VEdit::draw checking out
   5                         Cache::check_out 1
   6 VEdit::render checking in
   7                                                 ATrack::render checking out
   8                                                 Cache::check_out 1
   9 Cache::check_in 1
  10                         Cache::check_out 2
  11 Cache::check_in 2
  12 VEdit::render done
  13                                                                         VRender::process_buffer age video
  14                                                                         Cache::age_type 1
  15                                                                         Cache::lock_all 1
  16                                                                         Cache::lock_all 2
  17 but ATrack::render has locked check_out at this point.
  18                         VEdit::draw checking in
  19                         Cache::check_in 1
  20 but Cache::age_type has locked check_in and check_out can't be unlocked until
  21 VEdit completes