Because pre-v6 ARM lacks support for an atomic compare-and-swap, we
implement _lock_cas() as a restartable atomic squence that is checked
in the IRQ handler right before AST processing. (This is safe because,
for all practical purposes, there are no SMP pre-v6 ARM systems.)
This can serve as a model for other non-MP platforms that lack the
necessary atomic operations for mutexes (SuperH, for example).
Upshots of this change:
- kmutex_t is now down to 8 bytes on ARM; about as good as we can get.
- ARM2 systems don't have to trap and emulate SWP or SWPB for mutexes.
The acorn26 port is not updated by this commit to do the LOCK_CAS_CHECK.
That is left as an exercise for the port maintainer.
Reviewed and tested by Matt Thomas.
merge link_set_* sections into the text section for a.out kernels,
from sys/arch/arm/conf/ to sys/conf/ since there is no ARM specific
stuff in it and other ports would share it.
by Slava Semushin <slava.semushin@gmail.com>.
To verify that no nasty side effects of duplicate includes (or their
removal) have an effect here, I've compiled an i386/ALL kernel with
and without the patch, and the only difference in the resulting .o
files was in shifted line numbers in some assert() calls.
The comparison of the .o files was based on the output of "objdump -D".
Thanks to martin@ for the input on testing.
- finish implementing splraiseipl (and makeiplcookie).
http://mail-index.NetBSD.org/tech-kern/2006/07/01/0000.html
- complete workqueue(9) and fix its ipl problem, which is reported
to cause audio skipping.
- fix netbt (at least compilation problems) for some ports.
- fix PR/33218.
MACHINE. Thus, move it out of <arm/bootconfig.h> and put it into
<machine/bootconfig.h> on those MACHINEs (cats, hpcarm, and shark) where
it's used outside the file in which it's defined.
- Add COMPAT_15 to all the kernel that had COMPAT_14, for the sake of coherency
- Remove the only occurences of #ifdef COMPAT_15 in the tree: for the ARM
ports, COMPAT_15 was always used in conjunction with EXEC_AOUT. Only EXEC_AOUT
matters here.
This address kern/18407
