cvs commit: src/sys/kern kern_thread.c

[John Baldwin]

jhb         2004/03/01 15:07:58 PST

  FreeBSD src repository

  Modified files:
    sys/kern             kern_thread.c 
  Log:
  Check for TDF_SINTR before calling sleepq_abort() as there is a narrow
  race in between sleepq_add() and sleepq_catch_signals() in that setting
  td_wchan and TDF_SINTR is not atomic to sched_lock but only to the sleepq
  lock.  This band-aid will stop assertion failures, but there is perhaps a
  larger problem with the sleepq_add/sleepq_catch_signals race that I am not
  sure how to solve.  For the signals case the race is harmless because we
  always call cursig() after setting TDF_SINTR.  However, KSE doesn't do
  anything in sleepq_catch_signals() to check that this race was lost, so I
  am unsure if this race is harmful for this specific abort.
  
  Revision  Changes    Path
  1.172     +1 -1      src/sys/kern/kern_thread.c