docs/internals/tm-threadstates.dot

   1 digraph thread_states {
   2         // States
   3         alive;
   4         running;
   5         wait_mutex;
   6         wait_condvar;
   7         wait_join;
   8         zombie;
   9         dead;
  10
  11         // Legitimate transitions
  12         alive -> running;
  13         dead -> alive                   [ label="reused" ];
  14
  15         running -> wait_join            [ label="wait for another\nthread termination" ];
  16         wait_join -> running            [ label="target thread\nterminates" ];
  17
  18         running -> zombie               [ label="non-detached thread\nterminates" ];
  19         zombie -> dead                  [ label="join completed" ];
  20         running -> dead                 [ label="detached thread\nterminates" ];
  21
  22         running -> wait_mutex           [ label="wait for mutex\nacquisition" ];
  23         wait_mutex -> running           [ label="mutex\nacquired" ];
  24         wait_mutex -> running           [ label="mutex\ngiven up" ];
  25
  26         running -> wait_condvar         [ label="wait for condition variable" ];
  27         wait_condvar -> running         [ label="woken" ];
  28
  29         // How to handle bad actions
  30         wait_mutex -> zombie            [ style=dotted, label="thread dies\nwaiting" ];
  31         wait_mutex -> dead              [ style=dotted, label="thread dies\nwaiting" ];
  32         wait_mutex -> wait_condvar      [ style=dotted, label="waiting for\nmultiple objects" ];
  33         wait_mutex -> wait_join         [ style=dotted, label="waiting for\nmultiple objects" ];
  34
  35         wait_condvar -> zombie          [ style=dotted, label="thread dies\nwaiting" ];
  36         wait_condvar -> dead            [ style=dotted, label="thread dies\nwaiting" ];
  37         wait_condvar -> wait_mutex      [ style=dotted, label="waiting for\nmultiple objects" ];
  38         wait_condvar -> wait_join       [ style=dotted, label="waiting for\nmultiple objects" ];
  39
  40         wait_join -> zombie             [ style=dotted, label="thread dies\nwaiting" ];
  41         wait_join -> dead               [ style=dotted, label="thread dies\nwaiting" ];
  42         wait_join -> wait_condvar       [ style=dotted, label="waiting for\nmultiple objects" ];
  43         wait_join -> wait_mutex         [ style=dotted, label="waiting for\nmultiple objects" ];
  44
  45         zombie -> running               [ style=dotted, label="unholy\nresurrection" ];
  46         dead -> running                 [ style=dotted, label="unholy\nresurrection" ];
  47 }