K 10
svn:author
V 3
mjg
K 8
svn:date
V 27
2017-02-05T03:26:34.612813Z
K 7
svn:log
V 330
mtx: switch to fcmpset

The found value is passed to locking routines in order to reduce cacheline
accesses.

mtx_unlock grows an explicit check for regular unlock. On ll/sc architectures
the routine can fail even if the lock could have been handled by the inline
primitive.

Discussed with:	jhb
Tested by:	pho (previous version)

END