- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Rename VM_NDOMAIN into MAXMEMDOM and move it into machine/param.h in
order to match the MAXCPU concept. The change should also be useful
for consolidation and consistency.

Sponsored by: EMC / Isilon storage division
Obtained from: jeff
Reviewed by: alc

As discussed on -current, remove the hardcoded default maxswzone.

MFC after: 3 weeks

Bump MAXCPU for amd64, ia64 and XLP mips appropriately.
From now on, default values for FreeBSD will be 64 maxiumum supported
CPUs on amd64 and ia64 and 128 for XLP. All the other architectures
seem already capped appropriately (with the exception of sparc64 which
needs further support on jalapeno flavour).

Bump __FreeBSD_version in order to reflect KBI/KPI brekage introduced
during the infrastructure cleanup for supporting MAXCPU > 32. This
covers cpumask_t retiral too.

The switch is considered completed at the present time, so for whatever
bug you may experience that is reconducible to that area, please report
immediately.

Requested by: marcel, jchandra
Tested by: pluknet, sbruno
Approved by: re (kib)

Add the possibility to specify from kernel configs MAXCPU value.
This patch is going to help in cases like mips flavours where you
want a more granular support on MAXCPU.

No MFC is previewed for this patch.

Tested by: pluknet
Approved by: re (kib)

When compat32 binary asks for the value of hw.machine_arch, report the
name of 32bit sibling architecture instead of the host one. Do the
same for hw.machine on amd64.

Add a safety belt debug.adaptive_machine_arch sysctl, to turn the
substitution off.

Reviewed by: jhb, nwhitehorn
MFC after: 2 weeks

Uppercase the UL suffix on a constant, so Flexelint doesn't worry that
'u1' might have been intended. No, that does not make sense and yes
I have told them.

Add a new sysctl for reporting all of the supported page sizes.

Reviewed by: jhb
MFC after: 3 weeks

Get rid of the _NO_NAMESPACE_POLLUTION kludge by creating an
architecture specific include file containing the _ALIGN*
stuff which <sys/socket.h> needs.

Move multi-include protection back up to the top of the file and
name after the physical file rather than the aliased name.

Cleanup ALIGNED_POINTER:
o add to platforms where it was missing (arm, i386, powerpc, sparc64, sun4v)
o define as "1" on amd64 and i386 where there is no restriction
o make the type returned consistent with ALIGN
o remove _ALIGNED_POINTER
o make associated comments consistent

Reviewed by: bde, imp, marcel
Approved by: re (kensmith)

Now that amd64's kernel map is 512GB (SVN rev 192216), there is no reason
to cap its buffer map at 1GB.

MFC after: 6 weeks

Bump CACHE_LINE_SIZE to 128 for x86. Intel's manuals explicitly recommend
using 128 byte alignment for locks. (See IA-32 SDM Vol 3A 7.11.6.7)

Don't conditionally define CACHE_LINE_SHIFT, as we anticipate sizing
a fair number of static data structures, making this an unlikely
option to try to change without also changing source code. [1]

Change default cache line size on ia64, sparc64, and sun4v to 128
bytes, as this was what rtld-elf was already using on those
platforms. [2]

Suggested by: bde [1], jhb [2]
MFC after: 2 weeks

Add description and cautionary note regarding CACHE_LINE_SIZE.

MFC after: 2 weeks
Suggested by: alc

For each architecture, define CACHE_LINE_SHIFT and a derived
CACHE_LINE_SIZE constant. These constants are intended to
over-estimate the cache line size, and be used at compile-time
when a run-time tuning alternative isn't appropriate or
available.

Defaults for all architectures are 64 bytes, except powerpc
where it is 128 bytes (used on G5 systems).

MFC after: 2 weeks
Discussed on: arch@

Bump MAXCPU to 32 now that 32 CPU x86 systems exist.

Tested by: rwatson, mdtansca
Approved by: peter

Enhance pmap_change_attr() with the ability to demote 1GB page mappings.

Increase the ceiling on the size of the buffer map.

When building a kernel module, define MAXCPU the same as SMP so
that modules work with and without SMP.

By popular demand, move __HAVE_ACPI and __PCI_REROUTE_INTERRUPT into
param.h. Per request, I've placed these just after the
_NO_NAMESPACE_POLLUTION ifndef. I've not renamed anything yet, but
may since we don't need the __.

Submitted by: bde, jhb, scottl, many others.

Drop _MACHINE_ARCH and _MACHINE defines (not to be confused with
MACHINE_ARCH and MACHINE). Their purpose was to be able to test
in cpp(1), but cpp(1) only understands integer type expressions.
Using such unsupported expressions introduced a number of subtle
bugs, which were discovered by compiling with -Wundef.

Increase MAXCPU to 16 in SMP kernels so that APIC IDs from 0 to 15 are
allowed for CPUs.

Tested by: amd64 at cybernetwork dot org
Approved by: re (scottl)
MFC after: 1 week

MFi386: whitespace, copyright header, etc updates

Begin all license/copyright comments with /*-

Remove UAREA_PAGES.

Reviewed by: arch@

Turn PREEMPTION into a kernel option. Make sure that it's defined if
FULL_PREEMPTION is defined. Add a runtime warning to ULE if PREEMPTION is
enabled (code inspired by the PREEMPTION warning in kern_switch.c). This
is a possible MT5 candidate.

Turn off PREEMPTION by default while it gets debugged. It's been causing
4 weeks of problems including deadlocks and instant panics. Note that the
real bugs are likely in the scheduler.

Implement preemption of kernel threads natively in the scheduler rather
than as one-off hacks in various other parts of the kernel:
- Add a function maybe_preempt() that is called from sched_add() to
determine if a thread about to be added to a run queue should be
preempted to directly. If it is not safe to preempt or if the new
thread does not have a high enough priority, then the function returns
false and sched_add() adds the thread to the run queue. If the thread
should be preempted to but the current thread is in a nested critical
section, then the flag TDF_OWEPREEMPT is set and the thread is added
to the run queue. Otherwise, mi_switch() is called immediately and the
thread is never added to the run queue since it is switch to directly.
When exiting an outermost critical section, if TDF_OWEPREEMPT is set,
then clear it and call mi_switch() to perform the deferred preemption.
- Remove explicit preemption from ithread_schedule() as calling
setrunqueue() now does all the correct work. This also removes the
do_switch argument from ithread_schedule().
- Do not use the manual preemption code in mtx_unlock if the architecture
supports native preemption.
- Don't call mi_switch() in a loop during shutdown to give ithreads a
chance to run if the architecture supports native preemption since
the ithreads will just preempt DELAY().
- Don't call mi_switch() from the page zeroing idle thread for
architectures that support native preemption as it is unnecessary.
- Native preemption is enabled on the same archs that supported ithread
preemption, namely alpha, i386, and amd64.

This change should largely be a NOP for the default case as committed
except that we will do fewer context switches in a few cases and will
avoid the run queues completely when preempting.

Approved by: scottl (with his re@ hat)

Be a little more consistent in the naming of the PML4 defines.

Since we have additional kernel virtual address space, allow the buffer
cache to grow to 400M bytes.

Initial landing of SMP support for FreeBSD/amd64.

- This is heavily derived from John Baldwin's apic/pci cleanup on i386.
- I have completely rewritten or drastically cleaned up some other parts.
(in particular, bootstrap)
- This is still a WIP. It seems that there are some highly bogus bioses
on nVidia nForce3-150 boards. I can't stress how broken these boards
are. I have a workaround in mind, but right now the Asus SK8N is broken.
The Gigabyte K8NPro (nVidia based) is also mind-numbingly hosed.
- Most of my testing has been with SCHED_ULE. SCHED_4BSD works.
- the apic and acpi components are 'standard'.
- If you have an nVidia nForce3-150 board, you are stuck with 'device
atpic' in addition, because they somehow managed to forget to connect the
8254 timer to the apic, even though its in the same silicon! ARGH!
This directly violates the ACPI spec.

KSTACK_PAGES is a global option.

Migrate the thread stack management functions from the machine-dependent
to the machine-independent parts of the VM. At the same time, this
introduces vm object locking for the non-i386 platforms.

Two details:

1. KSTACK_GUARD has been removed in favor of KSTACK_GUARD_PAGES. The
different machine-dependent implementations used various combinations
of KSTACK_GUARD and KSTACK_GUARD_PAGES. To disable guard page, set
KSTACK_GUARD_PAGES to 0.

2. Remove the (unnecessary) clearing of PG_ZERO in vm_thread_new. In
5.x, (but not 4.x,) PG_ZERO can only be set if VM_ALLOC_ZERO is passed
to vm_page_alloc() or vm_page_grab().

Fix ALIGNED_POINTER(). sizeof((u_int32_t)) is not legal C.

Major pmap rework to take advantage of the larger address space on amd64
systems. Of note:
- Implement a direct mapped region using 2MB pages. This eliminates the
need for temporary mappings when getting ptes. This supports up to
512GB of physical memory for now. This should be enough for a while.
- Implement a 4-tier page table system. Most of the infrastructure is
there for 128TB of userland virtual address space, but only 512GB is
presently enabled due to a mystery bug somewhere. The design of this
was heavily inspired by the alpha pmap.c.
- The kernel is moved into the negative address space(!).
- The kernel has 2GB of KVM available.
- Provide a uma memory allocator to use the direct map region to take
advantage of the 2MB TLBs.
- Fixed some assumptions in the bus_space macros about the ability
to fit virtual addresses in an 'int'.

Notable missing things:
- pmap_growkernel() should be able to grow to 512GB of KVM by expanding
downwards below kernbase. The kernel must be at the top 2GB of the
negative address space because of gcc code generation strategies.
- need to fix the >512GB user vm code.

Approved by: re (blanket)

Commit MD parts of a loosely functional AMD64 port. This is based on
a heavily stripped down FreeBSD/i386 (brutally stripped down actually) to
attempt to get a stable base to start from. There is a lot missing still.
Worth noting:
- The kernel runs at 1GB in order to cheat with the pmap code. pmap uses
a variation of the PAE code in order to avoid having to worry about 4
levels of page tables yet.
- It boots in 64 bit "long mode" with a tiny trampoline embedded in the
i386 loader. This simplifies locore.s greatly.
- There are still quite a few fragments of i386-specific code that have
not been translated yet, and some that I cheated and wrote dumb C
versions of (bcopy etc).
- It has both int 0x80 for syscalls (but using registers for argument
passing, as is native on the amd64 ABI), and the 'syscall' instruction
for syscalls. int 0x80 preserves all registers, 'syscall' does not.
- I have tried to minimize looking at the NetBSD code, except in a couple
of places (eg: to find which register they use to replace the trashed
%rcx register in the syscall instruction). As a result, there is not a
lot of similarity. I did look at NetBSD a few times while debugging to
get some ideas about what I might have done wrong in my first attempt.

Repocopy from x86_64/... to amd64/...
Rename visible x86_64 references to amd64.
Kill MID_MACHINE, its a.out specific, the only platform that supports it
is i386. All of the other platforms should remove it too.

Initiate deorbit burn for the i386-only a.out related support. Moves are
under way to move the remnants of the a.out toolchain to ports. As the
comment in src/Makefile said, this stuff is deprecated and one should not
expect this to remain beyond 4.0-REL. It has already lasted WAY beyond
that.

Notable exceptions:
gcc - I have not touched the a.out generation stuff there.
ldd/ldconfig - still have some code to interface with a.out rtld.
old as/ld/etc - I have not removed these yet, pending their move to ports.
some includes - necessary for ldd/ldconfig for now.

Tested on: i386 (extensively), alpha

This is the start of the FreeBSD/x86_64 kernel.