the original ad-audiomp branch notes:
Add MP locking to the audio drivers.
Making the audio drivers MP safe is necessary before efforts
can be made to make the VM system MP safe.
The are two locks per device instance, an ISR lock and
a character device lock. The ISR lock replaces calls to
splaudio()/splx(), and will be held across calls to device
methods which were called at splaudio() before (e.g.
trigger_output). The character device lock is held across
calls to nearly all of the methods, excluding some only
used for initialization, e.g. get_locks.
Welcome to 5.99.57.
Merge from chap-midi branch, after
~month for review
Comments by thorpej@ drochner@ and Alexandre Ratchov
Incorporated: points by thorpej@ drochner@; preliminary support for
a stats-collecting ioctl suggested by martin@ from comments by A.R.
PR kern/32441 kern/32442 kern/32567 kern/32588 kern/32694 kern/33590
kern/33614 and one instance of kern/32651
ok martin@
