NAME    [Toc]    [Back]

     endtsleep, sleepinit, unsleep -- manage the queues of sleeping processes

SYNOPSIS    [Toc]    [Back]

     #include <sys/param.h>
     #include <sys/proc.h>

     void
     endtsleep(void *arg);

     void
     sleepinit(void);

     void
     unsleep(struct thread *td);

DESCRIPTION    [Toc]    [Back]

     The sleep queues used by msleep(9) and friends are stored in a hash
     array.  The address of the wait channel is used to generate an index into
     the array.  Each entry in the array is a queue of processes that are
     sleeping on wait channels that hash to that index.  msleep(9) places processes
 into their appropriate queues directly.  To handle timeouts, the
     endtsleep() function is registered as a timeout(9).  When the process is
     woken by either wakeup() or wakeup_one(), the timeout is revoked via
     untimeout(9).  If the process is not awakened soon enough, then
     endtsleep() is called with arg pointing to the struct proc of the process
     that timed out.  endtsleep() undoes the sleep and makes the process
     runnable if it is in the SSLEEP state.  The sleep queues and the hash
     array are protected internally by the sched_lock mutex.

     unsleep() simply removes the thread td from its sleep queue.

     sleepinit() is called during system startup and initializes the scheduler
     quantum (sched_quantum) and the sleep queues.

SEE ALSO    [Toc]    [Back]

     msleep(9), runqueue(9), scheduler(9)


FreeBSD 5.2.1		       November 3, 2000 		 FreeBSD 5.2.1