While timing a "no-op" build of the kernel (incrementally building the
kernel even though nothing changed) in the Chrome OS build system I
found that it was much slower than I expected.

Digging into things a bit, I found that quite a bit of the time was
spent invoking the C compiler even though we weren't actually building
anything.  Currently in the Chrome OS build system the C compiler is
called through a number of wrappers (one of which is written in
python!) and can take upwards of 100 ms to invoke even if we're not
doing anything difficult, so these invocations of the compiler were
taking a lot of time.  Worse the invocations couldn't seem to take
advantage of the multiple cores on my system.

Certainly it seems like we could make the compiler invocations in the
Chrome OS build system faster, but only to a point.  Inherently
invoking a program as big as a C compiler is a fairly heavy
operation.  Thus even if we can speed the compiler calls it made sense
to track down what was happening.

It turned out that all the compiler invocations were coming from
usages like this in the kernel's Makefile:

KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)

Due to the way cc-option and similar statements work the above
contains an implicit call to the C compiler.  ...and due to the fact
that we're storing the result in KBUILD_CFLAGS, a simply expanded
variable, the call will happen every time the Makefile is parsed, even
if there are no users of KBUILD_CFLAGS.

Rather than redoing this computation every time, it makes a lot of
sense to cache the result of all of the Makefile's compiler calls just
like we do when we compile a ".c" file to a ".o" file.  Conceptually
this is quite a simple idea.  ...and since the calls to invoke the
compiler and similar tools are centrally located in the Kbuild.include
file this doesn't even need to be super invasive.

Implementing the cache in a simple-to-use and efficient way is not
quite as simple as it first sounds, though.  To get maximum speed we
really want the cache in a format that make can natively understand
and make doesn't really have an ability to load/parse files. ...but
make _can_ import other Makefiles, so the solution is to store the
cache in Makefile format.  This requires coming up with a valid/unique
Makefile variable name for each value to be cached, but that's
solvable with some cleverness.

After this change, we'll automatically create a ".cache.mk" file that
will contain our cached variables.  We'll load this on each invocation
of make and will avoid recomputing anything that's already in our
cache.  The cache is stored in a format that it shouldn't need any
invalidation since anything that might change should affect the "key"
and any old cached value won't be used.
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NIngo Molnar <mingo@kernel.org>
Tested-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

$(kbuild-file) and Kbuild.include are included before the default
target "all".

We will add a target into Kbuild.include.  In advance, add a forward
declaration of the default target.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>

Accumulate subdir-{cc,as}flags-y directly to KBUILD_{A,C}FLAGS.
Remove KBUILD_SUBDIR_{AS,CC}FLAGS.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NCao jin <caoj.fnst@cn.fujitsu.com>

As kbuild document & commit 6588169d says: KBUILD_CFLAGS_MODULE is
used to add arch-specific options for $(CC). From commandline,
CFLAGS_MODULE shall be used.
Doesn't have any functional change, but just follow kbuild rules.
Signed-off-by: NCao jin <caoj.fnst@cn.fujitsu.com>
CC: linux-hexagon@vger.kernel.org
Acked-by: NRichard Kuo <rkuo@codeaurora.org>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

As kbuild document & commit 6588169d says: KBUILD_CFLAGS_MODULE is
used to add arch-specific options for $(CC). From commandline,
CFLAGS_MODULE shall be used.
Doesn't have any functional change, but just follow kbuild rules.
Signed-off-by: NCao jin <caoj.fnst@cn.fujitsu.com>
CC: Mark Salter <msalter@redhat.com>
CC: Aurelien Jacquiot <jacquiot.aurelien@gmail.com>
CC: linux-c6x-dev@linux-c6x.org
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

As kbuild document & commit 6588169d says: KBUILD_{C,LD}FLAGS_MODULE are
used to add arch-specific options for $(CC) and $(LD). From commandline,
{C,LD}FLAGS_MODULE shall be used.
Doesn't have any functional change, but just follow kbuild rules.
Signed-off-by: NCao jin <caoj.fnst@cn.fujitsu.com>
CC: Russell King <linux@armlinux.org.uk>
CC: linux-arm-kernel@lists.infradead.org
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

It has:
1. Move comments close to what it want to comment.
2. Comments cleanup & improvement.
Signed-off-by: NCao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

When compiling with `make CC=clang HOSTCC=clang`, I was seeing warnings
that clang did not recognize -fno-delete-null-pointer-checks for HOSTCC
targets.  These were added in commit 61163efa ("kbuild: LLVMLinux:
Add Kbuild support for building kernel with Clang").

Clang does not support -fno-delete-null-pointer-checks, so adding it to
HOSTCFLAGS if HOSTCC is clang does not make sense.

It's not clear why the other warnings were disabled, and just for
HOSTCFLAGS, but I can remove them, add -Werror to HOSTCFLAGS and compile
with clang just fine.
Suggested-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NNick Desaulniers <nick.desaulniers@gmail.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

The top Makefile is divided into some sections such as mixed targets,
config targets, build targets, etc.

When we build mixed targets, Kbuild just invokes submake to process
them one by one.  In this case, compiler-related variables like CC,
KBUILD_CFLAGS, etc. are unneeded.

Check what kind of targets we are building first, and parse variables
for building only when necessary.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

The first "_all" occurrence around line 120 is only visible when
KBUILD_SRC is unset.

If O=... is specified, the working directory is relocated, then the
only second occurrence around line 193 is visible, that is not set
to PHONY.

Move the first one to an always visible place.  This clarifies "_all"
is our default target and it is always set to PHONY.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>

Since commit 5e538790 ("sparc,sparc64: unify Makefile"), hdr-arch
and SRCARCH always match.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>

This script does not need to create .version; it will be created by
scripts/link-vmlinux.sh later.  Clean-up the code slightly.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Since commit 1f2bfbd0 ("kbuild: link of vmlinux moved to a
script"), it is easy to increment .version without using a temporary
file .old_version.

I do not see anybody who creates the .tmp_version.  Probably it is a
left-over of commit 4e25d8bb ("[PATCH] kbuild: adjust .version
updating").  Just remove it.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

<generated/compile.h> is created (or updated) when Kbuild descends
into the init/ directory.  In parallel building from a pristine
source tree, there is no guarantee <generated/compile.h> exists when
arch/hexagon/kernel/ptrace.c is compiled.

For hexagon architecture, we know UTS_MACHINE is a fixed string
"hexagon", so let's hard-code it, like many architectures do.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NRichard Kuo <rkuo@codeaurora.org>

Pull x86 fixes from Thomas Gleixner:
 "This contains the following fixes and improvements:

   - Avoid dereferencing an unprotected VMA pointer in the fault signal
     generation code

   - Fix inline asm call constraints for GCC 4.4

   - Use existing register variable to retrieve the stack pointer
     instead of forcing the compiler to create another indirect access
     which results in excessive extra 'mov %rsp, %<dst>' instructions

   - Disable branch profiling for the memory encryption code to prevent
     an early boot crash

   - Fix a sparse warning caused by casting the __user annotation in
     __get_user_asm_u64() away

   - Fix an off by one error in the loop termination of the error patch
     in the x86 sysfs init code

   - Add missing CPU IDs to various Intel specific drivers to enable the
     functionality on recent hardware

   - More (init) constification in the numachip code"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/asm: Use register variable to get stack pointer value
  x86/mm: Disable branch profiling in mem_encrypt.c
  x86/asm: Fix inline asm call constraints for GCC 4.4
  perf/x86/intel/uncore: Correct num_boxes for IIO and IRP
  perf/x86/intel/rapl: Add missing CPU IDs
  perf/x86/msr: Add missing CPU IDs
  perf/x86/intel/cstate: Add missing CPU IDs
  x86: Don't cast away the __user in __get_user_asm_u64()
  x86/sysfs: Fix off-by-one error in loop termination
  x86/mm: Fix fault error path using unsafe vma pointer
  x86/numachip: Add const and __initconst to numachip2_clockevent

Pull timer fixes from Thomas Gleixner:
 "This adds a new timer wheel function which is required for the
  conversion of the timer callback function from the 'unsigned long
  data' argument to 'struct timer_list *timer'. This conversion has two
  benefits:

   1) It makes struct timer_list smaller

   2) Many callers hand in a pointer to the timer or to the structure
      containing the timer, which happens via type casting both at setup
      and in the callback. This change gets rid of the typecasts.

  Once the conversion is complete, which is planned for 4.15, the old
  setup function and the intermediate typecast in the new setup function
  go away along with the data field in struct timer_list.

  Merging this now into mainline allows a smooth queueing of the actual
  conversion in the affected maintainer trees without creating
  dependencies"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  um/time: Fixup namespace collision
  timer: Prepare to change timer callback argument type

Pull smp/hotplug fixes from Thomas Gleixner:
 "This addresses the fallout of the new lockdep mechanism which covers
  completions in the CPU hotplug code.

  The lockdep splats are false positives, but there is no way to
  annotate that reliably. The solution is to split the completions for
  CPU up and down, which requires some reshuffling of the failure
  rollback handling as well"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smp/hotplug: Hotplug state fail injection
  smp/hotplug: Differentiate the AP completion between up and down
  smp/hotplug: Differentiate the AP-work lockdep class between up and down
  smp/hotplug: Callback vs state-machine consistency
  smp/hotplug: Rewrite AP state machine core
  smp/hotplug: Allow external multi-instance rollback
  smp/hotplug: Add state diagram

Pull scheduler fixes from Thomas Gleixner:
 "The scheduler pull request comes with the following updates:

   - Prevent a divide by zero issue by validating the input value of
     sysctl_sched_time_avg

   - Make task state printing consistent all over the place and have
     explicit state characters for IDLE and PARKED so they wont be
     displayed as 'D' state which confuses tools"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/sysctl: Check user input value of sysctl_sched_time_avg
  sched/debug: Add explicit TASK_PARKED printing
  sched/debug: Ignore TASK_IDLE for SysRq-W
  sched/debug: Add explicit TASK_IDLE printing
  sched/tracing: Use common task-state helpers
  sched/tracing: Fix trace_sched_switch task-state printing
  sched/debug: Remove unused variable
  sched/debug: Convert TASK_state to hex
  sched/debug: Implement consistent task-state printing

Pull perf fixes from Thomas Gleixner:

 - Prevent a division by zero in the perf aux buffer handling

 - Sync kernel headers with perf tool headers

 - Fix a build failure in the syscalltbl code

 - Make the debug messages of perf report --call-graph work correctly

 - Make sure that all required perf files are in the MANIFEST for
   container builds

 - Fix the atrr.exclude kernel handling so it respects the
   perf_event_paranoid and the user permissions

 - Make perf test on s390x work correctly

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/aux: Only update ->aux_wakeup in non-overwrite mode
  perf test: Fix vmlinux failure on s390x part 2
  perf test: Fix vmlinux failure on s390x
  perf tools: Fix syscalltbl build failure
  perf report: Fix debug messages with --call-graph option
  perf evsel: Fix attr.exclude_kernel setting for default cycles:p
  tools include: Sync kernel ABI headers with tooling headers
  perf tools: Get all of tools/{arch,include}/ in the MANIFEST

Pull  locking fixes from Thomas Gleixner:
 "Two fixes for locking:

   - Plug a hole the pi_stat->owner serialization which was changed
     recently and failed to fixup two usage sites.

   - Prevent reordering of the rwsem_has_spinner() check vs the
     decrement of rwsem count in up_write() which causes a missed
     wakeup"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/rwsem-xadd: Fix missed wakeup due to reordering of load
  futex: Fix pi_state->owner serialization

Pull irq fixes from Thomas Gleixner:

 - Add a missing NULL pointer check in free_irq()

 - Fix a memory leak/memory corruption in the generic irq chip

 - Add missing rcu annotations for radix tree access

 - Use ffs instead of fls when extracting data from a chip register in
   the MIPS GIC irq driver

 - Fix the unmasking of IPI interrupts in the MIPS GIC driver so they
   end up at the target CPU and not at CPU0

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irq/generic-chip: Don't replace domain's name
  irqdomain: Add __rcu annotations to radix tree accessors
  irqchip/mips-gic: Use effective affinity to unmask
  irqchip/mips-gic: Fix shifts to extract register fields
  genirq: Check __free_irq() return value for NULL

Pull objtool fixes from Thomas Gleixner:
 "Two small fixes for objtool:

   - Support frame pointer setup via 'lea (%rsp), %rbp' which was not
     yet supported and caused build warnings

   - Disable unreacahble warnings for GCC4.4 and older to avoid false
     positives caused by the compiler itself"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Support unoptimized frame pointer setup
  objtool: Skip unreachable warnings for GCC 4.4 and older

Pull mtd fixes from Boris Brezillon:

 - Fix partition alignment check in mtdcore.c

 - Fix a buffer overflow in the Atmel NAND driver

* tag 'mtd/fixes-for-4.14-rc3' of git://git.infradead.org/linux-mtd:
  mtd: nand: atmel: fix buffer overflow in atmel_pmecc_user
  mtd: Fix partition alignment check on multi-erasesize devices

Pull SCSI fixes from James Bottomley:
 "Eight mostly minor fixes for recently discovered issues in drivers"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: ILLEGAL REQUEST + ASC==27 => target failure
  scsi: aacraid: Add a small delay after IOP reset
  scsi: scsi_transport_fc: Also check for NOTPRESENT in fc_remote_port_add()
  scsi: scsi_transport_fc: set scsi_target_id upon rescan
  scsi: scsi_transport_iscsi: fix the issue that iscsi_if_rx doesn't parse nlmsg properly
  scsi: aacraid: error: testing array offset 'bus' after use
  scsi: lpfc: Don't return internal MBXERR_ERROR code from probe function
  scsi: aacraid: Fix 2T+ drives on SmartIOC-2000

Pull x86 platform drivers fix from Darren Hart:
 "Newly discovered species of fujitsu laptops break some assumptions
  about ACPI device pairings.

  fujitsu-laptop: Don't oops when FUJ02E3 is not present"

* tag 'platform-drivers-x86-v4.14-2' of git://git.infradead.org/linux-platform-drivers-x86:
  platform/x86: fujitsu-laptop: Don't oops when FUJ02E3 is not presnt

Merge tag 'led_fixes-4.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds

Pull LED fixes from Jacek Anaszewski:
 "Four fixes for the as3645a LED flash controller and one update to
  MAINTAINERS"

* tag 'led_fixes-4.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
  MAINTAINERS: Add entry for MediaTek PMIC LED driver
  as3645a: Unregister indicator LED on device unbind
  as3645a: Use integer numbers for parsing LEDs
  dt: bindings: as3645a: Use LED number to refer to LEDs
  as3645a: Use ams,input-max-microamp as documented in DT bindings

Pull waitid fix from Al Viro:
 "Fix infoleak in waitid()"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fix infoleak in waitid(2)

Pull btrfs fixes from David Sterba:
 "We've collected a bunch of isolated fixes, for crashes, user-visible
  behaviour or missing bits from other subsystem cleanups from the past.

  The overall number is not small but I was not able to make it
  significantly smaller. Most of the patches are supposed to go to
  stable"

* 'for-4.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: log csums for all modified extents
  Btrfs: fix unexpected result when dio reading corrupted blocks
  btrfs: Report error on removing qgroup if del_qgroup_item fails
  Btrfs: skip checksum when reading compressed data if some IO have failed
  Btrfs: fix kernel oops while reading compressed data
  Btrfs: use btrfs_op instead of bio_op in __btrfs_map_block
  Btrfs: do not backup tree roots when fsync
  btrfs: remove BTRFS_FS_QUOTA_DISABLING flag
  btrfs: propagate error to btrfs_cmp_data_prepare caller
  btrfs: prevent to set invalid default subvolid
  Btrfs: send: fix error number for unknown inode types
  btrfs: fix NULL pointer dereference from free_reloc_roots()
  btrfs: finish ordered extent cleaning if no progress is found
  btrfs: clear ordered flag on cleaning up ordered extents
  Btrfs: fix incorrect {node,sector}size endianness from BTRFS_IOC_FS_INFO
  Btrfs: do not reset bio->bi_ops while writing bio
  Btrfs: use the new helper wbc_to_write_flags

Pull MD fixes from Shaohua Li:
 "A few fixes for MD. Mainly fix a problem introduced in 4.13, which we
  retry bio for some code paths but not all in some situations"

* tag 'md/4.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  md/raid5: cap worker count
  dm-raid: fix a race condition in request handling
  md: fix a race condition for flush request handling
  md: separate request handling

Pull PCI fixes from Bjorn Helgaas:

 - fix CONFIG_PCI=n build error (introduced in v4.14-rc1) (Geert
   Uytterhoeven)

 - fix a race in sysfs driver_override store/show (Nicolai Stange)

* tag 'pci-v4.14-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: Fix race condition with driver_override
  PCI: Add dummy pci_acs_enabled() for CONFIG_PCI=n build

Pull drm fixes from Dave Airlie:
 "Regular fixes pull, some amdkfd, amdgpu, etnaviv, sun4i, qxl, tegra
  fixes.

  I've got an outstanding pull for i915 but it wasn't on an rc2 base so
  I wanted to ship these out first, I might get to it before rc3 or I
  might not"

* tag 'drm-fixes-for-v4.14-rc3' of git://people.freedesktop.org/~airlied/linux:
  drm/tegra: trace: Fix path to include
  qxl: fix framebuffer unpinning
  drm/sun4i: cec: Enable back CEC-pin framework
  drm/amdkfd: Print event limit messages only once per process
  drm/amdkfd: Fix kernel-queue wrapping bugs
  drm/amdkfd: Fix incorrect destroy_mqd parameter
  drm/radeon: disable hard reset in hibernate for APUs
  drm/amdgpu: revert tile table update for oland
  etnaviv: fix gem object list corruption
  etnaviv: fix submit error path
  qxl: fix primary surface handling
  drm/amdkfd: check for null dev to avoid a null pointer dereference

Pull IOMMU fixes from Joerg Roedel:

 - A comment fix for 'struct iommu_ops'

 - Format string fixes for AMD IOMMU, unfortunatly I missed that during
   review.

 - Limit mediatek physical addresses to 32 bit for v7s to fix a warning
   triggered in io-page-table code.

 - Fix dma-sync in io-pgtable-arm-v7s code

* tag 'iommu-fixes-v4.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu: Fix comment for iommu_ops.map_sg
  iommu/amd: pr_err() strings should end with newlines
  iommu/mediatek: Limit the physical address in 32bit for v7s
  iommu/io-pgtable-arm-v7s: Need dma-sync while there is no QUIRK_NO_DMA

Pull arm64 fixes from Catalin Marinas:

 - SPsel register initialisation on reset as the architecture defines
   its state as unknown

 - Use READ_ONCE when dereferencing pmd_t pointers to avoid race
   conditions in page_vma_mapped_walk() (or fast GUP) with concurrent
   modifications of the page table

 - Avoid invoking the mm fault handling code for kernel addresses (check
   against TASK_SIZE) which would otherwise result in calling
   might_sleep() in atomic context

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: fault: Route pte translation faults via do_translation_fault
  arm64: mm: Use READ_ONCE when dereferencing pointer to pte table
  arm64: Make sure SPsel is always set

Pull xen fixes from Juergen Gross:

 - avoid a warning when compiling with clang

 - consider read-only bits in xen-pciback when writing to a BAR

 - fix a boot crash of pv-domains

* tag 'for-linus-4.14c-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/mmu: Call xen_cleanhighmap() with 4MB aligned for page tables mapping
  xen-pciback: relax BAR sizing write value check
  x86/xen: clean up clang build warning

Pull kvm fixes from Paolo Bonzini:
 "Mixed bugfixes. Perhaps the most interesting one is a latent bug that
  was finally triggered by PCID support"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm/x86: Handle async PF in RCU read-side critical sections
  KVM: nVMX: Fix nested #PF intends to break L1's vmlauch/vmresume
  KVM: VMX: use cmpxchg64
  KVM: VMX: simplify and fix vmx_vcpu_pi_load
  KVM: VMX: avoid double list add with VT-d posted interrupts
  KVM: VMX: extract __pi_post_block
  KVM: PPC: Book3S HV: Check for updated HDSISR on P9 HDSI exception
  KVM: nVMX: fix HOST_CR3/HOST_CR4 cache

kernel_waitid() can return a PID, an error or 0.  rusage is filled in the first
case and waitid(2) rusage should've been copied out exactly in that case, *not*
whenever kernel_waitid() has not returned an error.  Compat variant shares that
braino; none of kernel_wait4() callers do, so the below ought to fix it.
Reported-and-tested-by: NAlexander Potapenko <glider@google.com>
Fixes: ce72a16f ("wait4(2)/waitid(2): separate copying rusage to userland")
Cc: stable@vger.kernel.org # v4.13
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Currently we use current_stack_pointer() function to get the value
of the stack pointer register. Since commit:

  f5caf621 ("x86/asm: Fix inline asm call constraints for Clang")

... we have a stack register variable declared. It can be used instead of
current_stack_pointer() function which allows to optimize away some
excessive "mov %rsp, %<dst>" instructions:

 -mov    %rsp,%rdx
 -sub    %rdx,%rax
 -cmp    $0x3fff,%rax
 -ja     ffffffff810722fd <ist_begin_non_atomic+0x2d>

 +sub    %rsp,%rax
 +cmp    $0x3fff,%rax
 +ja     ffffffff810722fa <ist_begin_non_atomic+0x2a>

Remove current_stack_pointer(), rename __asm_call_sp to current_stack_pointer
and use it instead of the removed function.
Signed-off-by: NAndrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170929141537.29167-1-aryabinin@virtuozzo.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Some routines in mem_encrypt.c are called very early in the boot process,
e.g. sme_encrypt_kernel(). When CONFIG_TRACE_BRANCH_PROFILING=y is defined
the resulting branch profiling associated with the check to see if SME is
active results in a kernel crash. Disable branch profiling for
mem_encrypt.c by defining DISABLE_BRANCH_PROFILING before including any
header files.
Reported-by: Nkernel test robot <lkp@01.org>
Signed-off-by: NTom Lendacky <thomas.lendacky@amd.com>
Acked-by: NBorislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170929162419.6016.53390.stgit@tlendack-t1.amdoffice.netSigned-off-by: NIngo Molnar <mingo@kernel.org>

Merge tag 'perf-urgent-for-mingo-4.14-20170928' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

- Fix syscalltbl build failure (Akemi Yagi)

- Fix attr.exclude_kernel setting for default cycles:p, this time for
  !root with kernel.perf_event_paranoid = -1 (Arnaldo Carvalho de Melo)

- Sync kernel ABI headers with tooling headers (Ingo Molnar)

- Remove misleading debug messages with --call-graph option (Mengting Zhang)

- Revert vmlinux symbol resolution patches for s390x (Thomas Richter)
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@kernel.org>