Acked-by: NTony Luck <tony.luck@intel.com>
Tested-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NMichael Kerrisk <mtk.manpages@gmail.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NDave Jones <davej@redhat.com>

The core page allocator ensures that page flags are zeroed when freeing
pages via free_pages_check.  A number of architectures (ARM, PPC, MIPS)
rely on this property to treat new pages as dirty with respect to the data
cache and perform the appropriate flushing before mapping the pages into
userspace.

This can lead to cache synchronisation problems when using hugepages,
since the allocator keeps its own pool of pages above the usual page
allocator and does not reset the page flags when freeing a page into the
pool.

This patch adds a new architecture hook, arch_clear_hugepage_flags, so
that architectures which rely on the page flags being in a particular
state for fresh allocations can adjust the flags accordingly when a page
is freed into the pool.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Cc: Michal Hocko <mhocko@suse.cz>
Reviewed-by: NMichal Hocko <mhocko@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Ease the deployment of clkdev by providing a default asm/clkdev.h for
use if the arch does not have an include/asm/clkdev.h.

Due to limitations in Kbuild we manually add clkdev.h to all
architectures that don't have one rather than having the header appear
by default.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

Make default just return 0.  The current default (checking
TIF_POLLING_NRFLAG) is taken to architectures that need it;
ones that don't do polling in their idle threads don't need
to defined TIF_POLLING_NRFLAG at all.

ia64 defined both TS_POLLING (used by its tsk_is_polling())
and TIF_POLLING_NRFLAG (not used at all).  Killed the latter...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Use the mapping of Elf_[SPE]hdr, Elf_Addr, Elf_Sym, Elf_Dyn, Elf_Rel/Rela,
ELF_R_TYPE() and ELF_R_SYM() to either the 32-bit version or the 64-bit version
into asm-generic/module.h for all arches bar MIPS.

Also, use the generic definition mod_arch_specific where possible.

To this end, I've defined three new config bools:

 (*) HAVE_MOD_ARCH_SPECIFIC

     Arches define this if they don't want to use the empty generic
     mod_arch_specific struct.

 (*) MODULES_USE_ELF_RELA

     Arches define this if their modules can contain RELA records.  This causes
     the Elf_Rela mapping to be emitted and allows apply_relocate_add() to be
     defined by the arch rather than have the core emit an error message.

 (*) MODULES_USE_ELF_REL

     Arches define this if their modules can contain REL records.  This causes
     the Elf_Rel mapping to be emitted and allows apply_relocate() to be
     defined by the arch rather than have the core emit an error message.

Note that it is possible to allow both REL and RELA records: m68k and mips are
two arches that do this.

With this, some arch asm/module.h files can be deleted entirely and replaced
with a generic-y marker in the arch Kbuild file.

Additionally, I have removed the bits from m32r and score that handle the
unsupported type of relocation record as that's now handled centrally.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

In arch ia64, has following definition:
extern u8 numa_slit[MAX_NUMNODES * MAX_NUMNODES];
#define node_distance(from,to) (numa_slit[(from) * num_online_nodes() + (to)])

num_online_nodes() is a variable value, it can be changed after hot-remove/add
a node.

In my practice, I found node distance is wrong after offline
a node in IA64 platform. For example system has 4 nodes:
node distances:
node   0   1   2   3
  0:  10  21  21  32
  1:  21  10  32  21
  2:  21  32  10  21
  3:  32  21  21  10

linux-drf:/sys/devices/system/node/node0 # cat distance
10  21  21  32
linux-drf:/sys/devices/system/node/node1 # cat distance
21  10  32  21

After offline node2:
linux-drf:/sys/devices/system/node/node0 # cat distance
10 21 32
linux-drf:/sys/devices/system/node/node1 # cat distance
32 21 32	--------->expected value is: 21  10  21
Signed-off-by: NJianguo Wu <wujianguo@huawei.com>
Signed-off-by: NJiang Liu <jiang.liu@huawei.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

All the original Xen headers have xen_pfn_t as mfn and pfn type, however
when they have been imported in Linux, xen_pfn_t has been replaced with
unsigned long. That might work for x86 and ia64 but it does not for arm.
Bring back xen_pfn_t and let each architecture define xen_pfn_t as they
see fit.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Changes in v2:
- remove pvclock hack;
- remove include linux/types.h from xen/interface/xen.h.
v3:
- Compile under IA64
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The archs that implement virtual cputime accounting all
flush the cputime of a task when it gets descheduled
and sometimes set up some ground initialization for the
next task to account its cputime.

These archs all put their own hooks in their context
switch callbacks and handle the off-case themselves.

Consolidate this by creating a new account_switch_vtime()
callback called in generic code right after a context switch
and that these archs must implement to flush the prev task
cputime and initialize the next task cputime related state.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Acked-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>

All the original Xen headers have xen_ulong_t as unsigned long type, however
when they have been imported in Linux, xen_ulong_t has been replaced with
unsigned long. That might work for x86 and ia64 but it does not for arm.
Bring back xen_ulong_t and let each architecture define xen_ulong_t as they
see fit.

Also explicitly size pointers (__DEFINE_GUEST_HANDLE) to 64 bit.


Changes in v3:

- remove the incorrect changes to multicall_entry;
- remove the change to apic_physbase.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The following build error occured during a ia64 build with
swap-over-NFS patches applied.

net/core/sock.c:274:36: error: initializer element is not constant
net/core/sock.c:274:36: error: (near initialization for 'memalloc_socks')
net/core/sock.c:274:36: error: initializer element is not constant

This is identical to a parisc build error. Fengguang Wu, Mel Gorman
and James Bottomley did all the legwork to track the root cause of
the problem. This fix and entire commit log is shamelessly copied
from them with one extra detail to change a dubious runtime use of
ATOMIC_INIT() to atomic_set() in drivers/char/mspec.c

Dave Anglin says:
> Here is the line in sock.i:
>
> struct static_key memalloc_socks = ((struct static_key) { .enabled =
> ((atomic_t) { (0) }) });

The above line contains two compound literals.  It also uses a designated
initializer to initialize the field enabled.  A compound literal is not a
constant expression.

The location of the above statement isn't fully clear, but if a compound
literal occurs outside the body of a function, the initializer list must
consist of constant expressions.

Cc: <stable@vger.kernel.org>
Signed-off-by: NTony Luck <tony.luck@intel.com>

The macro name is too generic and conflicts with
snd_soc_dai_link.platform_name, which triggers lots of build errors.
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

The iommu=group_mf is really no longer needed with the addition of ACS
support in IOMMU drivers creating groups.  Most multifunction devices
will now be grouped already.  If a device has gone to the trouble of
exposing ACS, trust that it works.  We can use the device specific ACS
function for fixing devices we trust individually.  This largely
reverts bcb71abe.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This is a preparatory patch for the KVM/ARM implementation. KVM/ARM will use
the KVM_IRQ_LINE ioctl, which is currently conditional on
__KVM_HAVE_IOAPIC, but ARM obviously doesn't have any IOAPIC support and we
need a separate define.
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

helpers parallel to set_restore_sigmask(), used in the next commits
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Historical prepare_to_copy() is mostly a no-op, duplicated for majority of
the architectures and the rest following the x86 model of flushing the extended
register state like fpu there.

Remove it and use the arch_dup_task_struct() instead.
Suggested-by: NOleg Nesterov <oleg@redhat.com>
Suggested-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1336692811-30576-1-git-send-email-suresh.b.siddha@intel.comAcked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Fixes klibc build on ia64 after 85f8f775.

Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Nmaximilian attems <max@stro.at>
Signed-off-by: NTony Luck <tony.luck@intel.com>

When the 32-bit compat code was deleted, we should also have removed
the task_size element from the thread structure - threads can only
be 64-bit now, so no need to keep track of how much virtual address
space each task can have ... everyone gets 0xa000000000000000.
Suggested-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Rather than requiring architectures that use gpiolib but don't have any
need to define anything custom to copy an asm/gpio.h provide a Kconfig
symbol which architectures must select in order to include gpio.h and
for other architectures just provide the trivial implementation directly.

This makes it much easier to do gpiolib updates and is also a step towards
making gpiolib APIs available on every architecture.

For architectures with existing boilerplate code leave a stub header in
place which warns on direct inclusion of asm/gpio.h and includes
linux/gpio.h to catch code that's doing this.  Direct inclusion of
asm/gpio.h has long been deprecated.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NJonas Bonn <jonas@southpole.se>
Acked-by: NTony Luck <tony.luck@intel.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

The current code groups up to 16 nodes in a level and then puts an
ALLNODES domain spanning the entire tree on top of that. This doesn't
reflect the numa topology and esp for the smaller not-fully-connected
machines out there today this might make a difference.

Therefore, build a proper numa topology based on node_distance().

Since there's no fixed numa layers anymore, the static SD_NODE_INIT
and SD_ALLNODES_INIT aren't usable anymore, the new code tries to
construct something similar and scales some values either on the
number of cpus in the domain and/or the node_distance() ratio.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: linux-alpha@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-sh@vger.kernel.org
Cc: Matt Turner <mattst88@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: sparclinux@vger.kernel.org
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86@kernel.org
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Greg Pearson <greg.pearson@hp.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: bob.picco@oracle.com
Cc: chris.mason@oracle.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-r74n3n8hhuc2ynbrnp3vt954@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Replace __HAVE_ARCH_TASK_ALLOCATOR and __HAVE_ARCH_THREAD_ALLOCATOR
with proper config switches.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20120505150142.371309416@linutronix.de

IA64 does not set CONFIG_ARCH_HAVE_IDLE_WAIT and cpuidle uses a
generic function now. Remove the unused code.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20120507175652.392394511@linutronix.de

Make the file names consistent with the naming conventions of irq subsystem.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Make the code consistent with the naming conventions of irq subsystem.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch introduces irq_remap_ops to hold implementation
specific function pointer to handle interrupt remapping. As
the first part the initialization functions for VT-d are
converted to these ops.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

MMIO that are split across a page boundary are currently broken - the
code does not expect to be aborted by the exit to userspace for the
first MMIO fragment.

This patch fixes the problem by generalizing the current code for handling
16-byte MMIOs to handle a number of "fragments", and changes the MMIO
code to create those fragments.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Michel Lespinasse cleaned up the futex calling conventions in commit
37a9d912 ("futex: Sanitize cmpxchg_futex_value_locked API").

But the ia64 implementation was subtly broken.  Gcc does not know that
register "r8" will be updated by the fault handler if the cmpxchg
instruction takes an exception.  So it feels safe in letting the
initialization of r8 slide to after the cmpxchg.  Result: we always
return 0 whether the user address faulted or not.

Fix by moving the initialization of r8 into the __asm__ code so gcc
won't move it.

Reported-by: <emeric.maschino@gmail.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=42757
Tested-by: <emeric.maschino@gmail.com>
Acked-by: NMichel Lespinasse <walken@google.com>
Cc: stable@vger.kernel.org # v2.6.39+
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

commit 93f37888

    "Fix ia64 build errors (fallout from system.h disintegration)"

introduced arch/ia64/include/asm/cmpxchg.h as a temporary
build fix and stated:

    "... leave the migration of xchg() and cmpxchg() to this new
     header file for a future patch."

Migrate the appropriate chunks from asm/intrinsics.h and fix
the whitespace issues in the migrated chunk.

Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

When a host stops or suspends a VM it will set a flag to show this.  The
watchdog will use these functions to determine if a softlockup is real, or the
result of a suspended VM.
Signed-off-by: NEric B Munson <emunson@mgebm.net>
asm-generic changes Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The kvm_vcpu_kick function performs roughly the same funcitonality on
most all architectures, so we shouldn't have separate copies.

PowerPC keeps a pointer to interchanging waitqueues on the vcpu_arch
structure and to accomodate this special need a
__KVM_HAVE_ARCH_VCPU_GET_WQ define and accompanying function
kvm_arch_vcpu_wq have been defined. For all other architectures this
is a generic inline that just returns &vcpu->wq;
Acked-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The empty asm/cmpxchg.h file that was provided as a temporary build fix
for the asm/system.h disintgration build problem should really include
<asm/intrinsics.h> to make definitions of xchg() and cmpxchg()
available.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix this build error on ia64:

  In file included from include/linux/sched.h:92,
                  from arch/ia64/kernel/asm-offsets.c:9:
  include/linux/llist.h:59:25: error: asm/cmpxchg.h: No such file or directory
  make[1]: *** [arch/ia64/kernel/asm-offsets.s] Error 1

Right now we don't seem to need any actual contents for the
asm/cmpxchg.h to make the build work ...  so leave the migration of
xchg() and cmpxchg() to this new header file for a future patch.

Also process.c needs <asm/switch_to.h> (for definition of pfm_syst_info).
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Delete all instances of asm/system.h as they should be redundant by this
point.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Disintegrate asm/system.h for IA64.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NTony Luck <tony.luck@intel.com>
cc: linux-ia64@vger.kernel.org

Adapt core x86 and IA64 architecture code for dma_map_ops changes: replace
alloc/free_coherent with generic alloc/free methods.
Signed-off-by: NAndrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: NKyungmin Park <kyungmin.park@samsung.com>
[removed swiotlb related changes and replaced it with wrappers,
 merged with IA64 patch to avoid inter-patch dependences in intel-iommu code]
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NTony Luck <tony.luck@intel.com>

For the hypervisor to take advantage of the MWAIT support it needs
to extract from the ACPI _CST the register address. But the
hypervisor does not have the support to parse DSDT so it relies on
the initial domain (dom0) to parse the ACPI Power Management information
and push it up to the hypervisor. The pushing of the data is done
by the processor_harveset_xen module which parses the information that
the ACPI parser has graciously exposed in 'struct acpi_processor'.

For the ACPI parser to also expose the Cx states for MWAIT, we need
to expose the MWAIT capability (leaf 1). Furthermore we also need to
expose the MWAIT_LEAF capability (leaf 5) for cstate.c to properly
function.

The hypervisor could expose these flags when it traps the XEN_EMULATE_PREFIX
operations, but it can't do it since it needs to be backwards compatible.
Instead we choose to use the native CPUID to figure out if the MWAIT
capability exists and use the XEN_SET_PDC query hypercall to figure out
if the hypervisor wants us to expose the MWAIT_LEAF capability or not.

Note: The XEN_SET_PDC query was implemented in c/s 23783:
"ACPI: add _PDC input override mechanism".

With this in place, instead of
 C3 ACPI IOPORT 415
we get now
 C3:ACPI FFH INTEL MWAIT 0x20

Note: The cpu_idle which would be calling the mwait variants for idling
never gets set b/c we set the default pm_idle to be the hypercall variant.
Acked-by: NJan Beulich <JBeulich@suse.com>
[v2: Fix missing header file include and #ifdef]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>