Commit Graph

155 Commits

Author SHA1 Message Date
David E. O'Brien
677b542ea2 Use __FBSDID(). 2003-06-11 00:56:59 +00:00
Jeff Roberson
980c75b4d8 - Remove the blocked pointer from the umtx structure.
- Use a hash of umtx queues to queue blocked threads.  We hash on pid and the
   virtual address of the umtx structure.  This eliminates cases where we
   previously held a lock across a casuptr call.

Reviwed by:	jhb (quickly)
2003-06-03 05:24:46 +00:00
Jeff Roberson
0003d1b74e - Create a new lock, umtx_lock, for use instead of the proc lock for
protecting the umtx queues.  We can't use the proc lock because we need
   to hold the lock across calls to casuptr, which can fault.

Approved by:	re
2003-05-25 18:18:32 +00:00
Jake Burkholder
cef57e7624 - Make casuptr return the old value of the location we're trying to update,
and change the umtx code to expect this.

Reviewed by:	jeff
2003-04-02 08:02:27 +00:00
Jeff Roberson
69404b5090 - Add an api for doing smp safe locks in userland.
- umtx_lock() is defined as an inline in umtx.h.  It tries to do an
   uncontested acquire of a lock which falls back to the _umtx_lock()
   system-call if that fails.
 - umtx_unlock() is also an inline which falls back to _umtx_unlock() if the
   uncontested unlock fails.
 - Locks are keyed off of the thr_id_t of the currently running thread which
   is currently just the pointer to the 'struct thread' in kernel.
 - _umtx_lock() uses the proc pointer to synchronize access to blocked thread
   queues which are stored in the first blocked thread.
2003-04-01 01:10:42 +00:00