Create a new header lwp_private.h to contain _lwp_getprivate_fast,
_lwp_gettcb_fast, _lwp_settcb and remove them from mcontext.h, so that:
1. we don't need special hacks to hide them
2. we can include <lwp.h> where needed to get the necessary prototypes
without redefining them locally.

Undo previous lwp.h change.

Split __lwp_getprivate_fast and __lwp_*tcb from mcontext.h into a separate
lwp.h file.

branches: 1.50.32;
Add multiboot 2 support to x86 bootloaders

multiboot 2 is required to boot Xen on an EFI system.
This also require a kernel patch for properly discovering
the ACPI RSDP, which is available after 20190912, in
src/sys/arch/x86/acpi/acpi_machdep.c 1.26-1.28

There are a few missing bit in this multiboot 2 implementation
(which are unused by Xen):
- Header tags Address, Freambuffer, and Relocatable are ignored
- Tags APM and Network are not provided
- Tags ACPI old and ACP new are only provided for ACPI boot
- Tag boot device does not provides the subpart (BSD disklabel partition)

Notes:
- multiboot2 is disabled in dosboot, otherwise the binary
gets too big and build fails.
- in src/sys/arch/i386/stand/efiboot, consinit() is renamed
as efi_consinit() to avoid prototype conflicts in src/sys/sys/systm.h

branches: 1.49.4;
Remove the kernel PMC code. Sent yesterday on tech-kern@.

This change:

* Removes "options PERFCTRS", the associated includes, and the associated
ifdefs. In doing so, it removes several XXXSMPs in the MI code, which is
good.

* Removes the PMC code of ARM XSCALE.

* Removes all the pmc.h files. They were all empty, except for ARM XSCALE.

* Reorders the x86 PMC code not to rely on the legacy pmc.h file. The
definitions are put in sysarch.h.

* Removes the kern/sys_pmc.c file, and along with it, the sys_pmc_control
and sys_pmc_get_info syscalls. They are marked as OBSOL in kern,
netbsd32 and rump.

* Removes the pmc_evid_t and pmc_ctr_t types.

* Removes all the associated man pages. The sets are marked as obsolete.

branches: 1.48.2; 1.48.4;
Remove vm86.

Pass 4.

Remove ibcs2_machdep.h on i386, and don't install it.

Move freebsd_machdep.h into sys/compat/freebsd, and don't install it. Now,
the compat_freebsd files are all contained in sys/compat/freebsd.

Unlink svr4_machdep.h.

branches: 1.44.10;
Add cpu_rng, a framework for simple on-CPU random number generators.

branches: 1.43.4;
Rename sljitarch.h to sljit_machdep.h.

branches: 1.42.2;
Change i386 to use x86/fpu.c instead of i386/isa/npx.c
This changes the trap10 and trap13 code to call directly into fpu.c,
removing all the code for T_ARITHTRAP, T_XMM and T_FPUNDA from i386/trap.c
Not all of the code thate appeared to handle fpu traps was ever called!
Most of the changes just replace the include of machine/npx.h with x86/fpu.h
(or remove it entirely).

branches: 1.41.2;
Build sljit test when MKSLJIT != no and set MKSLJIT to yes on amd64 and i386.

branches: 1.40.2;
on x86, <machine/cpufunc.h> only pulls in <x86/cpufunc.h>. The latter
is not installed to userland and noone missed it, so the former ones
can not be useful either. Don't install them.

branches: 1.39.2;
Retire varargs.h support. Move machine/stdarg.h logic into MI
sys/stdarg.h and expect compiler to provide proper builtins, defaulting
to the GCC interface. lint still has a special fallback.
Reduce abuse of _BSD_VA_LIST_ by defining __va_list by default and
derive va_list as required by standards.

On i386, good-bye <machine/bus.h>.

Add support for fenv.h interface for i386 and amd64.

Submitted by Stathis Kamperis as part of GSoC 2010 and ported from
FreeBSD.

branches: 1.36.10; 1.36.24; 1.36.30; 1.36.32;
- Make __cpu_simple_lock and similar real functions and patch at runtime.
- Remove old x86 atomic ops.
- Drop text alignment back to 16 on i386 (really, this time).
- Minor cleanup.

branches: 1.35.2; 1.35.6;
- Remove I486_CPU, I586_CPU, I686_CPU options. They buy us nothing and
clutter the code significantly.
- Remove pccons.

branches: 1.34.6; 1.34.12; 1.34.22; 1.34.24; 1.34.28; 1.34.30;
Merge newlock2 to head.

branches: 1.33.4;
don't install <machine/db_machdep.h>, this is kernel only

branches: 1.32.2;
Revert yesterday's change that attempted to fix the detection of the
boot device when using a Multiboot boot loader. It couldn't work because
these boot loaders do not pass a checksum of the disk so matchbiosdisk()
cannot really find any matches. I should have gone to sleep before
commiting...

Found by xtraeme@.

branches: 1.31.2;
When booting an i386 kernel with Multiboot, properly detect the boot device
by looking it up in the x86_alldisks table (instead of trying to match it
to 'wd*' manually).

In order to do this, move the cpu_rootconf function from x86 common code
to amd64 and i386 specific one. This way, i386 can do an extra step (call
the appropriate Multiboot code) in the appropriate place (after
x86_matchbiosdisks and before findroot()).

Implement support for 'The Multiboot Specification' so that i386 kernels
can be booted directly from Multiboot-compliant boot loaders (e.g. GRUB).
See the added multiboot(8) manual page for more information.

No objections in tech-kern@; only positive comments.

branches: 1.29.2; 1.29.4;
merge ktrace-lwp.

branches: 1.28.2;
"loadfile_machdep.h" should not be installed as pointed out by
Izumi Tsutsui. This needs to be fixed in the build process.

Install "loadfile_machdep.h" to fix build of "libsa".

Factor out W{CHAR,INT}_{MAX,MIN} into their own header file.

branches: 1.25.2;
Don't install machine/mouse.h on i386 and prep; there are no users for
the old busmouse interface any longer, we use wsmouse now.

Merge the nathanw_sa branch.

Remove KDIR=, since SYS_INCLUDE=symlinks and KDIR are not supported any more.

install intrdefs.h so it can be used by intr.h (and libkvm)

Merge Bill Sommerfeld's i386 MP branch. This code has some known
caveats, but works quite well in a lot of MP cases, and all
UP cases that I have tested. Parts of this will hopefully be
reworked in the not-too-distant future.

Merge the gehenna-devsw branch into the trunk.

This merge changes the device switch tables from static array to
dynamically generated by config(8).

- All device switches is defined as a constant structure in device drivers.

- The new grammer ``device-major'' is introduced to ``files''.

device-major <prefix> char <num> [block <num>] [<rules>]

- All device major numbers must be listed up in port dependent majors.<arch>
by using this grammer.

- Added the new naming convention.
The name of the device switch must be <prefix>_[bc]devsw for auto-generation
of device switch tables.

- The backward compatibility of loading block/character device
switch by LKM framework is broken. This is necessary to convert
from block/character device major to device name in runtime and vice versa.

- The restriction to assign device major by LKM is completely removed.
We don't need to reserve LKM entries for dynamic loading of device switch.

- In compile time, device major numbers list is packed into the kernel and
the LKM framework will refer it to assign device major number dynamically.

branches: 1.19.2; 1.19.8; 1.19.12;
Add mtrr.h to INCS list to get installed on a make includes

branches: 1.18.4; 1.18.6;
Add definitions of C99 integer format conversion macros.
XXX Fastest minimum-width integer types haven't been decided upon yet.

Add definitions of C99 specified-width integer type limits.
XXX Fastest minimum-width integer types haven't been decided upon yet.

Add definitions of C99 integer constant macros.
Tidy Makefiles up a little.

Add definitions of C99 minimum-width and greatest-width integer types.
XXX Fastest minimum-width integer types haven't been decided upon yet.

branches: 1.14.4;
Machine pmc.h

Add <machine/int_types.h>, which provides namespace-pure definitions
of exact-width integer types.

Require that each each MACHINE/MACHINE_ARCH supply a lock.h. This file
contains the values __SIMPLELOCK_LOCKED and __SIMPLELOCK_UNLOCKED, which
replace the old SIMPLELOCK_LOCKED and SIMPLELOCK_UNLOCKED. These files
are also required to supply inline functions __cpu_simple_lock(),
__cpu_simple_lock_try(), and __cpu_simple_unlock() if locking is to be
supported on that platform (i.e. if MULTIPROCESSOR is defined in the
_KERNEL case). Change these functions to take an int * (&alp->lock_data)
rather than the struct simplelock * itself.

These changes make it possible for userland to use the locking primitives
by including <machine/lock.h>.

Install "endian_machdep.h" required for "sys/endian.h".

C99: Define a NAN macro in <math.h> which evaulates to a constant expression of
a single-precision quiet NaN; only to be defined on platforms that do support
this value.

Don't let loadfile_machdep.h make it to /usr/include - the i386
stand Makefiles already set up the compile environment so that
machine/loadfile_machdep.h can be found.

branches: 1.8.2; 1.8.4; 1.8.6;
PMAP_NEW is no longer optional on the i386; the old pmap's page table
allocation strategy no longer works at all. Move pmap.new.* to pmap.*.

To read the revision history of PMAP_NEW up until this merge, use cvs
rlog of the old pmap.new.* files.

MD defines for the MI loadfile

branches: 1.6.4;
Add an ieee.h.

Add missing backslashes between continued lines.

Oups, need byte_swap.h too. Pointed out by Robert V. Baron

Move the bswap functions from libutil to libc (this bups the
minor of libc and the major of libutil). For little-endian architectures
merge the bnswap() assembly versions with nto* and hton* using symbols
aliasing. Use symbol renaming for the bswap function in this case to avoid
namespace pollution.
Declare bswap* in machine/bswap.h, not machine/endian.h. For little-endian
machines, common code for inline macros go in machine/byte_swap.h
Sync libkern with libc.
Adjust #include in kernel sources for machine/bswap.h.

linux_machdep.h has moved.

Rework the way kernel include files are installed. In the new method,
as with user-land programs, include files are installed by each directory
in the tree that has includes to install. (This allows more flexibility
as to what gets installed, makes 'partial installs' easier, and gives us
more options as to which machines' includes get installed at any given
time.) The old SYS_INCLUDES={symlinks,copies} behaviours are _both_
still supported, though at least one bug in the 'symlinks' case is
fixed by this change. Include files can't be build before installation,
so directories that have includes as targets (e.g. dev/pci) have to move
those targets into a different Makefile.