K 10
svn:author
V 6
marcel
K 8
svn:date
V 27
2013-02-12T17:38:35.547368Z
K 7
svn:log
V 707
Eliminate the PC_CURTHREAD symbol and load the current thread's
thread structure pointer atomically from r13 (the pcpu pointer)
for the current CPU/core.
Add a CTASSERT in machdep.c to make sure that pc_curthread is in
fact the first field in struct pcpu.

The only non-atomic operations left were those related to process-
space operations, such as casuword, subyte, suword16, fubyte,
fuword16, copyin, copyout and their variations.

The casuword function has been re-structured more complete than
the others. This way we have an example of a better bundling
without introducing a lot of risk when we get it wrong. The
other functions can be rebundled in separate commits and with
the appropriate testing.

END