cvs commit: src/sys/kern kern_condvar.c kern_synch.c kern_thread.c subr_sleepqueue.c src/sys/sys proc.h sleepqueue.h

[John Baldwin]

jhb         2004-08-19 11:31:42 UTC

  FreeBSD src repository

  Modified files:
    sys/kern             kern_condvar.c kern_synch.c kern_thread.c 
                         subr_sleepqueue.c 
    sys/sys              proc.h sleepqueue.h 
  Log:
  Now that the return value semantics of cv's for multithreaded processes
  have been unified with that of msleep(9), further refine the sleepq
  interface and consolidate some duplicated code:
  - Move the pre-sleep checks for theaded processes into a
    thread_sleep_check() function in kern_thread.c.
  - Move all handling of TDF_SINTR to be internal to subr_sleepqueue.c.
    Specifically, if a thread is awakened by something other than a signal
    while checking for signals before going to sleep, clear TDF_SINTR in
    sleepq_catch_signals().  This removes a sched_lock lock/unlock combo in
    that edge case during an interruptible sleep.  Also, fix
    sleepq_check_signals() to properly handle the condition if TDF_SINTR is
    clear rather than requiring the callers of the sleepq API to notice
    this edge case and call a non-_sig variant of sleepq_wait().
  - Clarify the flags arguments to sleepq_add(), sleepq_signal() and
    sleepq_broadcast() by creating an explicit submask for sleepq types.
    Also, add an explicit SLEEPQ_MSLEEP type rather than a magic number of
    0.  Also, add a SLEEPQ_INTERRUPTIBLE flag for use with sleepq_add() and
    move the setting of TDF_SINTR to sleepq_add() if this flag is set rather
    than sleepq_catch_signals().  Note that it is the caller's responsibility
    to ensure that sleepq_catch_signals() is called if and only if this flag
    is passed to the preceeding sleepq_add().  Note that this also removes a
    sched_lock lock/unlock pair from sleepq_catch_signals().  It also ensures
    that for an interruptible sleep, TDF_SINTR is always set when
    TD_ON_SLEEPQ() is true.
  
  Revision  Changes    Path
  1.51      +16 -39    src/sys/kern/kern_condvar.c
  1.258     +16 -28    src/sys/kern/kern_synch.c
  1.194     +19 -0     src/sys/kern/kern_thread.c
  1.11      +23 -9     src/sys/kern/subr_sleepqueue.c
  1.393     +1 -0      src/sys/sys/proc.h
  1.4       +4 -1      src/sys/sys/sleepqueue.h