cvs commit: src/lib/libpthread/thread thr_cond.c thr_mutex.c

[Daniel Eischen]

deischen    2003/07/17 19:46:30 PDT

  FreeBSD src repository

  Modified files:
    lib/libpthread/thread thr_cond.c thr_mutex.c 
  Log:
  Add a preemption point when a mutex or condition variable is
  handed-off/signaled to a higher priority thread.  Note that when
  there are idle KSEs that could run the higher priority thread,
  we still add the preemption point because it seems to take the
  kernel a while to schedule an idle KSE.  The drawbacks are that
  threads will be swapped more often between CPUs (KSEs) and
  that there will be an extra userland context switch (the idle
  KSE is still woken and will probably resume the preempted
  thread).  We'll revisit this if and when idle CPU/KSE wakeup
  times improve.
  
  Inspired by:    Petri Helenius <pete at he.iki.fi>
  Reviewed by:    davidxu
  
  Revision  Changes    Path
  1.47      +8 -0      src/lib/libpthread/thread/thr_cond.c
  1.38      +10 -6     src/lib/libpthread/thread/thr_mutex.c