The memcg uncharging code that is involved towards the end of a page's
lifetime - truncation, reclaim, swapout, migration - is impressively
complicated and fragile.

Because anonymous and file pages were always charged before they had their
page->mapping established, uncharges had to happen when the page type
could still be known from the context; as in unmap for anonymous, page
cache removal for file and shmem pages, and swap cache truncation for swap
pages.  However, these operations happen well before the page is actually
freed, and so a lot of synchronization is necessary:

- Charging, uncharging, page migration, and charge migration all need
  to take a per-page bit spinlock as they could race with uncharging.

- Swap cache truncation happens during both swap-in and swap-out, and
  possibly repeatedly before the page is actually freed.  This means
  that the memcg swapout code is called from many contexts that make
  no sense and it has to figure out the direction from page state to
  make sure memory and memory+swap are always correctly charged.

- On page migration, the old page might be unmapped but then reused,
  so memcg code has to prevent untimely uncharging in that case.
  Because this code - which should be a simple charge transfer - is so
  special-cased, it is not reusable for replace_page_cache().

But now that charged pages always have a page->mapping, introduce
mem_cgroup_uncharge(), which is called after the final put_page(), when we
know for sure that nobody is looking at the page anymore.

For page migration, introduce mem_cgroup_migrate(), which is called after
the migration is successful and the new page is fully rmapped.  Because
the old page is no longer uncharged after migration, prevent double
charges by decoupling the page's memcg association (PCG_USED and
pc->mem_cgroup) from the page holding an actual charge.  The new bits
PCG_MEM and PCG_MEMSW represent the respective charges and are transferred
to the new page during migration.

mem_cgroup_migrate() is suitable for replace_page_cache() as well,
which gets rid of mem_cgroup_replace_page_cache().  However, care
needs to be taken because both the source and the target page can
already be charged and on the LRU when fuse is splicing: grab the page
lock on the charge moving side to prevent changing pc->mem_cgroup of a
page under migration.  Also, the lruvecs of both pages change as we
uncharge the old and charge the new during migration, and putback may
race with us, so grab the lru lock and isolate the pages iff on LRU to
prevent races and ensure the pages are on the right lruvec afterward.

Swap accounting is massively simplified: because the page is no longer
uncharged as early as swap cache deletion, a new mem_cgroup_swapout() can
transfer the page's memory+swap charge (PCG_MEMSW) to the swap entry
before the final put_page() in page reclaim.

Finally, page_cgroup changes are now protected by whatever protection the
page itself offers: anonymous pages are charged under the page table lock,
whereas page cache insertions, swapin, and migration hold the page lock.
Uncharging happens under full exclusion with no outstanding references.
Charging and uncharging also ensure that the page is off-LRU, which
serializes against charge migration.  Remove the very costly page_cgroup
lock and set pc->flags non-atomically.

[mhocko@suse.cz: mem_cgroup_charge_statistics needs preempt_disable]
[vdavydov@parallels.com: fix flags definition]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Tested-by: Jet Chen <jet.chen@intel.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Tested-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

These patches rework memcg charge lifetime to integrate more naturally
with the lifetime of user pages.  This drastically simplifies the code and
reduces charging and uncharging overhead.  The most expensive part of
charging and uncharging is the page_cgroup bit spinlock, which is removed
entirely after this series.

Here are the top-10 profile entries of a stress test that reads a 128G
sparse file on a freshly booted box, without even a dedicated cgroup (i.e.
 executing in the root memcg).  Before:

    15.36%              cat  [kernel.kallsyms]   [k] copy_user_generic_string
    13.31%              cat  [kernel.kallsyms]   [k] memset
    11.48%              cat  [kernel.kallsyms]   [k] do_mpage_readpage
     4.23%              cat  [kernel.kallsyms]   [k] get_page_from_freelist
     2.38%              cat  [kernel.kallsyms]   [k] put_page
     2.32%              cat  [kernel.kallsyms]   [k] __mem_cgroup_commit_charge
     2.18%          kswapd0  [kernel.kallsyms]   [k] __mem_cgroup_uncharge_common
     1.92%          kswapd0  [kernel.kallsyms]   [k] shrink_page_list
     1.86%              cat  [kernel.kallsyms]   [k] __radix_tree_lookup
     1.62%              cat  [kernel.kallsyms]   [k] __pagevec_lru_add_fn

After:

    15.67%           cat  [kernel.kallsyms]   [k] copy_user_generic_string
    13.48%           cat  [kernel.kallsyms]   [k] memset
    11.42%           cat  [kernel.kallsyms]   [k] do_mpage_readpage
     3.98%           cat  [kernel.kallsyms]   [k] get_page_from_freelist
     2.46%           cat  [kernel.kallsyms]   [k] put_page
     2.13%       kswapd0  [kernel.kallsyms]   [k] shrink_page_list
     1.88%           cat  [kernel.kallsyms]   [k] __radix_tree_lookup
     1.67%           cat  [kernel.kallsyms]   [k] __pagevec_lru_add_fn
     1.39%       kswapd0  [kernel.kallsyms]   [k] free_pcppages_bulk
     1.30%           cat  [kernel.kallsyms]   [k] kfree

As you can see, the memcg footprint has shrunk quite a bit.

   text    data     bss     dec     hex filename
  37970    9892     400   48262    bc86 mm/memcontrol.o.old
  35239    9892     400   45531    b1db mm/memcontrol.o

This patch (of 4):

The memcg charge API charges pages before they are rmapped - i.e.  have an
actual "type" - and so every callsite needs its own set of charge and
uncharge functions to know what type is being operated on.  Worse,
uncharge has to happen from a context that is still type-specific, rather
than at the end of the page's lifetime with exclusive access, and so
requires a lot of synchronization.

Rewrite the charge API to provide a generic set of try_charge(),
commit_charge() and cancel_charge() transaction operations, much like
what's currently done for swap-in:

  mem_cgroup_try_charge() attempts to reserve a charge, reclaiming
  pages from the memcg if necessary.

  mem_cgroup_commit_charge() commits the page to the charge once it
  has a valid page->mapping and PageAnon() reliably tells the type.

  mem_cgroup_cancel_charge() aborts the transaction.

This reduces the charge API and enables subsequent patches to
drastically simplify uncharging.

As pages need to be committed after rmap is established but before they
are added to the LRU, page_add_new_anon_rmap() must stop doing LRU
additions again.  Revive lru_cache_add_active_or_unevictable().

[hughd@google.com: fix shmem_unuse]
[hughd@google.com: Add comments on the private use of -EAGAIN]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Aleksei hit the soft lockup during reading /proc/PID/smaps.  David
investigated the problem and suggested the right fix.

while_each_thread() is racy and should die, this patch updates
vm_is_stack().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Aleksei Besogonov <alex.besogonov@gmail.com>
Tested-by: Aleksei Besogonov <alex.besogonov@gmail.com>
Suggested-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This reverts commit a6406168 ("slab: remove BAD_ALIEN_MAGIC").

commit a6406168 ("slab: remove BAD_ALIEN_MAGIC") assumes that the
system with !CONFIG_NUMA has only one memory node.  But, it turns out to
be false by the report from Geert.  His system, m68k, has many memory
nodes and is configured in !CONFIG_NUMA.  So it couldn't boot with above
change.

Here goes his failure report.

  With latest mainline, I'm getting a crash during bootup on m68k/ARAnyM:

  enable_cpucache failed for radix_tree_node, error 12.
  kernel BUG at /scratch/geert/linux/linux-m68k/mm/slab.c:1522!
  *** TRAP #7 ***   FORMAT=0
  Current process id is 0
  BAD KERNEL TRAP: 00000000
  Modules linked in:
  PC: [<0039c92c>] kmem_cache_init_late+0x70/0x8c
  SR: 2200  SP: 00345f90  a2: 0034c2e8
  d0: 0000003d    d1: 00000000    d2: 00000000    d3: 003ac942
  d4: 00000000    d5: 00000000    a0: 0034f686    a1: 0034f682
  Process swapper (pid: 0, task=0034c2e8)
  Frame format=0
  Stack from 00345fc4:
          002f69ef 002ff7e5 000005f2 000360fa 0017d806 003921d4 00000000
          00000000 00000000 00000000 00000000 00000000 003ac942 00000000
          003912d6
  Call Trace: [<000360fa>] parse_args+0x0/0x2ca
   [<0017d806>] strlen+0x0/0x1a
   [<003921d4>] start_kernel+0x23c/0x428
   [<003912d6>] _sinittext+0x2d6/0x95e

  Code: f7e5 4879 002f 69ef 61ff ffca 462a 4e47 <4879> 0035 4b1c 61ff
  fff0 0cc4 7005 23c0 0037 fd20 588f 265f 285f 4e75 48e7 301c
  Disabling lock debugging due to kernel taint
  Kernel panic - not syncing: Attempted to kill the idle task!

Although there is a alternative way to fix this issue such as disabling
use of alien cache on !CONFIG_NUMA, but, reverting issued commit is better
to me in this time.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull microblaze updates from Michal Simek:
 - add new syscall and fix comment
 - fix udelay implementation
 - fix libgcc for modules

* tag 'microblaze-3.17-rc1' of git://git.monstr.eu/linux-2.6-microblaze:
  microblaze: Change libgcc-style functions from lib-y to obj-y
  microblaze: Wire-up renameat2 syscall
  microblaze: Add syscall number comment
  microblaze: delay.h fix udelay and ndelay for 8 bit args

Pull avr32 fix from Hans-Christian Egtvedt.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/egtvedt/linux-avr32:
  avr32: fix error return code

Pull powerpc updates from Ben Herrenschmidt:
 "This is the powerpc new goodies for 3.17.  The short story:

  The biggest bit is Michael removing all of pre-POWER4 processor
  support from the 64-bit kernel.  POWER3 and rs64.  This gets rid of a
  ton of old cruft that has been bitrotting in a long while.  It was
  broken for quite a few versions already and nobody noticed.  Nobody
  uses those machines anymore.  While at it, he cleaned up a bunch of
  old dusty cabinets, getting rid of a skeletton or two.

  Then, we have some base VFIO support for KVM, which allows assigning
  of PCI devices to KVM guests, support for large 64-bit BARs on
  "powernv" platforms, support for HMI (Hardware Management Interrupts)
  on those same platforms, some sparse-vmemmap improvements (for memory
  hotplug),

  There is the usual batch of Freescale embedded updates (summary in the
  merge commit) and fixes here or there, I think that's it for the
  highlights"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (102 commits)
  powerpc/eeh: Export eeh_iommu_group_to_pe()
  powerpc/eeh: Add missing #ifdef CONFIG_IOMMU_API
  powerpc: Reduce scariness of interrupt frames in stack traces
  powerpc: start loop at section start of start in vmemmap_populated()
  powerpc: implement vmemmap_free()
  powerpc: implement vmemmap_remove_mapping() for BOOK3S
  powerpc: implement vmemmap_list_free()
  powerpc: Fail remap_4k_pfn() if PFN doesn't fit inside PTE
  powerpc/book3s: Fix endianess issue for HMI handling on napping cpus.
  powerpc/book3s: handle HMIs for cpus in nap mode.
  powerpc/powernv: Invoke opal call to handle hmi.
  powerpc/book3s: Add basic infrastructure to handle HMI in Linux.
  powerpc/iommu: Fix comments with it_page_shift
  powerpc/powernv: Handle compound PE in config accessors
  powerpc/powernv: Handle compound PE for EEH
  powerpc/powernv: Handle compound PE
  powerpc/powernv: Split ioda_eeh_get_state()
  powerpc/powernv: Allow to freeze PE
  powerpc/powernv: Enable M64 aperatus for PHB3
  powerpc/eeh: Aux PE data for error log
  ...

Pull MIPS updates from Ralf Baechle:
 "This is the main pull request for 3.17.  It contains:

   - misc Cavium Octeon, BCM47xx, BCM63xx and Alchemy  updates
   - MIPS ptrace updates and cleanups
   - various fixes that will also go to -stable
   - a number of cleanups and small non-critical fixes.
   - NUMA support for the Loongson 3.
   - more support for MSA
   - support for MAAR
   - various FP enhancements and fixes"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (139 commits)
  MIPS: jz4740: remove unnecessary null test before debugfs_remove
  MIPS: Octeon: remove unnecessary null test before debugfs_remove_recursive
  MIPS: ZBOOT: implement stack protector in compressed boot phase
  MIPS: mipsreg: remove duplicate MIPS_CONF4_FTLBSETS_SHIFT
  MIPS: Bonito64: remove a duplicate define
  MIPS: Malta: initialise MAARs
  MIPS: Initialise MAARs
  MIPS: detect presence of MAARs
  MIPS: define MAAR register accessors & bits
  MIPS: mark MSA experimental
  MIPS: Don't build MSA support unless it can be used
  MIPS: consistently clear MSA flags when starting & copying threads
  MIPS: 16 byte align MSA vector context
  MIPS: disable preemption whilst initialising MSA
  MIPS: ensure MSA gets disabled during boot
  MIPS: fix read_msa_* & write_msa_* functions on non-MSA toolchains
  MIPS: fix MSA context for tasks which don't use FP first
  MIPS: init upper 64b of vector registers when MSA is first used
  MIPS: save/disable MSA in lose_fpu
  MIPS: preserve scalar FP CSR when switching vector context
  ...

Pull s390 updates from Martin Schwidefsky:
 "Mostly cleanups and bug-fixes, with two exceptions.

  The first is lazy flushing of I/O-TLBs for PCI to improve performance,
  the second is software dirty bits in the pmd for the madvise-free
  implementation"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (24 commits)
  s390/locking: Reenable optimistic spinning
  s390/mm: implement dirty bits for large segment table entries
  KVM: s390/mm: Fix page table locking vs. split pmd lock
  s390/dasd: fix camel case
  s390/3215: fix hanging console issue
  s390/irq: improve displayed interrupt order in /proc/interrupts
  s390/seccomp: fix error return for filtered system calls
  s390/pci: introduce lazy IOTLB flushing for DMA unmap
  dasd: fix error recovery for alias devices during format
  dasd: fix list_del corruption during format
  dasd: fix unresponsive device during format
  dasd: use aliases for formatted devices during format
  s390/pci: fix kmsg component
  s390/kdump: Return NOTIFY_OK for all actions other than MEM_GOING_OFFLINE
  s390/watchdog: Fix module name in Kconfig help text
  s390/dasd: replace seq_printf by seq_puts
  s390/dasd: replace pr_warning by pr_warn
  s390/dasd: Move EXPORT_SYMBOL after function/variable
  s390/dasd: remove unnecessary null test before debugfs_remove
  s390/zfcp: use qdio buffer helpers
  ...

Convert a zero return value on error to a negative one, as returned
elsewhere in the function.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
identifier ret; expression e1,e2;
@@
(
if (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>

Merge incoming from Andrew Morton:
 - Various misc things.
 - arch/sh updates.
 - Part of ocfs2.  Review is slow.
 - Slab updates.
 - Most of -mm.
 - printk updates.
 - lib/ updates.
 - checkpatch updates.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (226 commits)
  checkpatch: update $declaration_macros, add uninitialized_var
  checkpatch: warn on missing spaces in broken up quoted
  checkpatch: fix false positives for --strict "space after cast" test
  checkpatch: fix false positive MISSING_BREAK warnings with --file
  checkpatch: add test for native c90 types in unusual order
  checkpatch: add signed generic types
  checkpatch: add short int to c variable types
  checkpatch: add for_each tests to indentation and brace tests
  checkpatch: fix brace style misuses of else and while
  checkpatch: add --fix option for a couple OPEN_BRACE misuses
  checkpatch: use the correct indentation for which()
  checkpatch: add fix_insert_line and fix_delete_line helpers
  checkpatch: add ability to insert and delete lines to patch/file
  checkpatch: add an index variable for fixed lines
  checkpatch: warn on break after goto or return with same tab indentation
  checkpatch: emit a warning on file add/move/delete
  checkpatch: add test for commit id formatting style in commit log
  checkpatch: emit fewer kmalloc_array/kcalloc conversion warnings
  checkpatch: improve "no space after cast" test
  checkpatch: allow multiple const * types
  ...

Pull networking fixes from David Miller:
 "This fixes the most immediate fallout from yesterday's networking
  merge:

   1) sock_tx_timestamp() must not clear the passed in tx_flags, but
      rather add to them.  Fix from Eric Dumazet.

   2) The hyperv driver sendbuf region increase needs to be decreased
      slightly to handle older backends.  From KY Srinivasan.

   3) Fix RCU lockdep splats in netlink diag after recent hashing
      changes, from Thomas Graf.

   4) The new IPV6_FLOWLABEL was given a socket option number that
      overlapped with an existing IP6 tables one, breaking ip6_tables.
      Fixed by Pablo Neira Ayuso"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  netlink: hold nl_sock_hash_lock during diag dump
  tcp: md5: check md5 signature without socket lock
  net: fix USB network driver config option.
  net: reallocate new socket option number for IPV6_AUTOFLOWLABEL
  vmxnet3: fix decimal printf format specifiers prefixed with 0x
  net-timestamp: cumulative tcp timestamping fixes
  hyperv: Adjust the size of sendbuf region to support ws2008r2
  cxgb4: Fix for SR-IOV VF initialization
  net-timestamp: sock_tx_timestamp() fix

Pull trivial tree changes from Jiri Kosina:
 "Summer edition of trivial tree updates"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
  doc: fix two typos in watchdog-api.txt
  irq-gic: remove file name from heading comment
  MAINTAINERS: Add miscdevice.h to file list for char/misc drivers.
  scsi: mvsas: mv_sas.c: Fix for possible null pointer dereference
  doc: replace "practise" with "practice" in Documentation
  befs: remove check for CONFIG_BEFS_RW
  scsi: doc: fix 'SCSI_NCR_SETUP_MASTER_PARITY'
  drivers/usb/phy/phy.c: remove a leading space
  mfd: fix comment
  cpuidle: fix comment
  doc: hpfall.c: fix missing null-terminate after strncpy call
  usb: doc: hotplug.txt code typos
  kbuild: fix comment in Makefile.modinst
  SH: add proper prompt to SH_MAGIC_PANEL_R2_VERSION
  ARM: msm: Remove MSM_SCM
  crypto: Remove MPILIB_EXTRA
  doc: CN: remove dead link, kerneltrap.org no longer works
  media: update reference, kerneltrap.org no longer works
  hexagon: update reference, kerneltrap.org no longer works
  doc: LSM: update reference, kerneltrap.org no longer works
  ...

Pull HID updates from Jiri Kosina:
 "Some highlights:

   - hid-sony improvements of Sixaxis device support by Antonio Ospite
   - hid-hyperv driven devices can now be used as wakeup source, by
     Dexuan Cui
   - hid-lenovo driver is now more generic and supports more devices, by
     Jamie Lentin
   - hid-huion now supports wider range of tablets, by Nikolai
     Kondrashov
   - other various unsorted fixes and device ID additions"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (30 commits)
  HID: hyperv: register as a wakeup source
  HID: sony: Default initialize all elements of the LED max_brightness array to 1
  HID: huion: Fix sparse warnings
  HID: usbhid: Use flag HID_DISCONNECTED when a usb device is removed
  HID: ignore jabra gn9350e
  HID: cp2112: add I2C mode
  HID: use multi input quirk for 22b9:2968
  HID: rmi: only bind the hid-rmi driver to the mouse interface of composite USB devices
  HID: rmi: check that report ids exist in the report_id_hash before accessing their size
  HID: lenovo: Add support for Compact (BT|USB) keyboard
  HID: lenovo: Don't call function in condition, show error codes
  HID: lenovo: Prepare support for adding other devices
  HID: lenovo: Rename hid-lenovo-tpkbd to hid-lenovo
  HID: huion: Handle tablets with UC-Logic vendor ID
  HID: huion: Switch to generating report descriptor
  HID: huion: Don't ignore other interfaces
  HID: huion: Use "tablet" instead of specific model
  HID: add quirk for 0x04d9:0xa096 device
  HID: i2c-hid: call the hid driver's suspend and resume callbacks
  HID: rmi: change logging level of log messages related to unexpected reports
  ...

Pull watchdog updates from Wim Van Sebroeck:
 - remove unnecessary checks after platform_get_resource()
 - fix watchdog api documentation typo's
 - imx2_wdt: adds big endianness support
 - move restart code to the sunxi watchdog driver

* git://www.linux-watchdog.org/linux-watchdog:
  wdt: sunxi: Move restart code to the watchdog driver
  Documentation: fix two typos in watchdog-api.txt
  watchdog: imx2_wdt: adds big endianness support.
  watchdog: shwdt: Remove the unnecessary check of resource after platform_get_resource()
  watchdog: lantiq_wdt: Remove the un-necessary check of resource after platform_get_resource()
  watchdog: dw_wdt: Remove the un-necessary check after platform_get_resource()

Pull ACPI and power management updates from Rafael Wysocki:
 "Again, ACPICA leads the pack (47 commits), followed by cpufreq (18
  commits) and system suspend/hibernation (9 commits).

  From the new code perspective, the ACPICA update brings ACPI 5.1 to
  the table, including a new device configuration object called _DSD
  (Device Specific Data) that will hopefully help us to operate device
  properties like Device Trees do (at least to some extent) and changes
  related to supporting ACPI on ARM.

  Apart from that we have hibernation changes making it use radix trees
  to store memory bitmaps which should speed up some operations carried
  out by it quite significantly.  We also have some power management
  changes related to suspend-to-idle (the "freeze" sleep state) support
  and more preliminary changes needed to support ACPI on ARM (outside of
  ACPICA).

  The rest is fixes and cleanups pretty much everywhere.

  Specifics:

   - ACPICA update to upstream version 20140724.  That includes ACPI 5.1
     material (support for the _CCA and _DSD predefined names, changes
     related to the DMAR and PCCT tables and ARM support among other
     things) and cleanups related to using ACPICA's header files.  A
     major part of it is related to acpidump and the core code used by
     that utility.  Changes from Bob Moore, David E Box, Lv Zheng,
     Sascha Wildner, Tomasz Nowicki, Hanjun Guo.

   - Radix trees for memory bitmaps used by the hibernation core from
     Joerg Roedel.

   - Support for waking up the system from suspend-to-idle (also known
     as the "freeze" sleep state) using ACPI-based PCI wakeup signaling
     (Rafael J Wysocki).

   - Fixes for issues related to ACPI button events (Rafael J Wysocki).

   - New device ID for an ACPI-enumerated device included into the
     Wildcat Point PCH from Jie Yang.

   - ACPI video updates related to backlight handling from Hans de Goede
     and Linus Torvalds.

   - Preliminary changes needed to support ACPI on ARM from Hanjun Guo
     and Graeme Gregory.

   - ACPI PNP core cleanups from Arjun Sreedharan and Zhang Rui.

   - Cleanups related to ACPI_COMPANION() and ACPI_HANDLE() macros
     (Rafael J Wysocki).

   - ACPI-based device hotplug cleanups from Wei Yongjun and Rafael J
     Wysocki.

   - Cleanups and improvements related to system suspend from Lan
     Tianyu, Randy Dunlap and Rafael J Wysocki.

   - ACPI battery cleanup from Wei Yongjun.

   - cpufreq core fixes from Viresh Kumar.

   - Elimination of a deadband effect from the cpufreq ondemand governor
     and intel_pstate driver cleanups from Stratos Karafotis.

   - 350MHz CPU support for the powernow-k6 cpufreq driver from Mikulas
     Patocka.

   - Fix for the imx6 cpufreq driver from Anson Huang.

   - cpuidle core and governor cleanups from Daniel Lezcano, Sandeep
     Tripathy and Mohammad Merajul Islam Molla.

   - Build fix for the big_little cpuidle driver from Sachin Kamat.

   - Configuration fix for the Operation Performance Points (OPP)
     framework from Mark Brown.

   - APM cleanup from Jean Delvare.

   - cpupower utility fixes and cleanups from Peter Senna Tschudin,
     Andrey Utkin, Himangi Saraogi, Rickard Strandqvist, Thomas
     Renninger"

* tag 'pm+acpi-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (118 commits)
  ACPI / LPSS: add LPSS device for Wildcat Point PCH
  ACPI / PNP: Replace faulty is_hex_digit() by isxdigit()
  ACPICA: Update version to 20140724.
  ACPICA: ACPI 5.1: Update for PCCT table changes.
  ACPICA/ARM: ACPI 5.1: Update for GTDT table changes.
  ACPICA/ARM: ACPI 5.1: Update for MADT changes.
  ACPICA/ARM: ACPI 5.1: Update for FADT changes.
  ACPICA: ACPI 5.1: Support for the _CCA predifined name.
  ACPICA: ACPI 5.1: New notify value for System Affinity Update.
  ACPICA: ACPI 5.1: Support for the _DSD predefined name.
  ACPICA: Debug object: Add current value of Timer() to debug line prefix.
  ACPICA: acpihelp: Add UUID support, restructure some existing files.
  ACPICA: Utilities: Fix local printf issue.
  ACPICA: Tables: Update for DMAR table changes.
  ACPICA: Remove some extraneous printf arguments.
  ACPICA: Update for comments/formatting. No functional changes.
  ACPICA: Disassembler: Add support for the ToUUID opererator (macro).
  ACPICA: Remove a redundant cast to acpi_size for ACPI_OFFSET() macro.
  ACPICA: Work around an ancient GCC bug.
  ACPI / processor: Make it possible to get local x2apic id via _MAT
  ...

Pull SCSI updates from James Bottomley:
 "This patch set consists of the usual driver updates (ufs, storvsc,
  pm8001 hpsa).  It also has removal of the user space target driver
  code (everyone is using LIO now), a partial PCI MSI-X update, more
  multi-queue updates, conversion to 64 bit LUNs (so we could
  theoretically cope with any LUN returned by a device) and placeholder
  support for the ZBC device type (Shingle drives), plus an assortment
  of minor updates and bug fixes"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (143 commits)
  scsi: do not issue SCSI RSOC command to Promise Vtrak E610f
  vmw_pvscsi: Use pci_enable_msix_exact() instead of pci_enable_msix()
  pm8001: Fix invalid return when request_irq() failed
  lpfc: Remove superfluous call to pci_disable_msix()
  isci: Use pci_enable_msix_exact() instead of pci_enable_msix()
  bfa: Use pci_enable_msix_exact() instead of pci_enable_msix()
  bfa: Cleanup bfad_setup_intr() function
  bfa: Do not call pci_enable_msix() after it failed once
  fnic: Use pci_enable_msix_exact() instead of pci_enable_msix()
  scsi: use short driver name for per-driver cmd slab caches
  scsi_debug: support scsi-mq, queues and locks
  Drivers: add blist flags
  scsi: ufs: fix endianness sparse warnings
  scsi: ufs: make undeclared functions static
  bnx2i: Update driver version to 2.7.10.1
  pm8001: fix a memory leak in nvmd_resp
  pm8001: fix update_flash
  pm8001: fix a memory leak in flash_update
  pm8001: Cleaning up uninitialized variables
  pm8001: Fix to remove null pointer checks that could never happen
  ...

Pull sound updates from Takashi Iwai:
 "There've been many updates in ASoC side at this time, especially the
  framework enhancement for multiple CODECs on a single DAI and more
  componentization works.

  The only major change in ALSA core is the addition of timestamp type
  in sw_params field.  This should behave in backward compatible way.

  Other than that, there are lots of small changes and new drivers in
  wide range, including a large code cut in HD-audio driver for
  deprecated static quirks.  Some highlights are below:

  ALSA Core:
   - Add the new timestamp type field to sw_params to choose
     MONOTONIC_RAW type

  HD-audio:
   - Continued conversion to standard printk macros, generic code
     cleanups
   - Removal of obsoleted static quirk codes for Conexant and C-Media
     codecs
   - Fixups for HP Envy TS, Dell XPS 15, HP and Dell mute/mic LED,
     Gigabyte BXBT-2807 mobo
   - Intel Braswell support

  ASoC:
   - Support for multiple CODECs attached to a single DAI, enabling
     systems with for example multiple DAC/speaker drivers on a single
     link, contributed by Benoit Cousson based on work from Misael Lopez
     Cruz
   - Support for byte controls larger than 256 bytes based on the use of
     TLVs contributed by Omair Mohammed Abdullah
   - More componentisation work from Lars-Peter Clausen
   - The remainder of the conversions of CODEC drivers to params_width()
     by Mark Brown
   - Drivers for Cirrus Logic CS4265, Freescale i.MX ASRC blocks,
     Realtek RT286 and RT5670, Rockchip RK3xxx I2S controllers and Texas
     Instruments TAS2552
   - Lots of updates and fixes, especially to the DaVinci, Intel,
     Freescale, Realtek, and rcar drivers"

* tag 'sound-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (402 commits)
  ALSA: usb-audio: Whitespace cleanups for sound/usb/midi.*
  ALSA: usb-audio: Respond to suspend and resume callbacks for MIDI input
  sound/oss/pss: Remove typedefs pss_mixerdata and pss_confdata
  sound/oss/opl3: Remove typedef opl_devinfo
  ALSA: fireworks: fix specifiers in format strings for propper output
  ASoC: imx-audmux: Use uintptr_t for port numbers
  ASoC: davinci: Enable menuconfig entry for McASP
  ASoC: fsl_asrc: Don't access members of config before checking it
  ASoC: fsl_sarc_dma: Check pair before using it
  ASoC: adau1977: Fix truncation warning on 64 bit architectures
  ALSA: virtuoso: add Xonar Essence STX II support
  ALSA: riptide: fix %d confusingly prefixed with 0x in format strings
  ALSA: fireworks: fix %d confusingly prefixed with 0x in format strings
  ALSA: hda - add codec ID for Braswell display audio codec
  ALSA: hda - add PCI IDs for Intel Braswell
  ALSA: usb-audio: Adjust Gamecom 780 volume level
  ALSA: usb-audio: improve dmesg source grepability
  ASoC: rt5670: Fix duplicate const warnings
  ASoC: rt5670: Staticise non-exported symbols
  ASoC: Intel: update stream only on stream IPC msgs
  ...

Pull HSI changes from Sebastian Reichel:
 "Misc fixes in SSI related drivers"

* tag 'hsi-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-hsi:
  HSI: omap_ssi: Fix return value check in ssi_debug_add_ctrl()
  HSI: omap_ssi_port: Fix return value check in ssi_debug_add_port()
  HSI: ssi_protocol: Fix sparse non static symbol warning
  drivers/hsi/controllers/omap_ssi{,_port}.c: fix failure checks

Pull power supply changes from Sebastian Reichel:
 - Added iPaq h3xxx battery driver
 - Added Broadcom STB reset driver
 - DT support for rx51-battery
 - misc. fixes

* tag 'for-v3.17' of git://git.infradead.org/battery-2.6:
  ipaq_micro_battery: fix sparse non static symbol warning
  power: add driver for battery reading on iPaq h3xxx
  power: twl4030_charger: detect battery presence prior to enabling charger
  power: reset: Add reboot driver for brcmstb
  power_supply: Fix sparse non static symbol warning
  power_supply: Add inlmt,iterm, min/max temp props
  charger: tps65090: Allow charger module to be used when no irq
  power/reset: Fix GPL v2 license string typo
  power: poweroff: gpio: convert to use descriptors
  bq27000: report missing device better.
  bq27x00_battery: Introduce the use of the managed version of kzalloc
  Documentation: DT: Document rx51-battery binding
  rx51_battery: convert to iio consumer
  bq2415x_charger: Fix Atomic Sleep Bug

The function is used by VFIO driver, which might be built as a
dynamic module. So it should be exported.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Although RCU protection would be possible during diag dump, doing
so allows for concurrent table mutations which can render the
in-table offset between individual Netlink messages invalid and
thus cause legitimate sockets to be skipped in the dump.

Since the diag dump is relatively low volume and consistency is
more important than performance, the table mutex is held during
dump.
Reported-by: Andrey Wagin <avagin@gmail.com>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Fixes: e341694e ("netlink: Convert netlink_lookup() to use RCU protected hash table")
Signed-off-by: David S. Miller <davem@davemloft.net>

Using uninitialized_var reports a false positive for "Missing blank line
after declarations".

Fix it by adding uninitialized_var to the $declaration_macros exceptions
list.

Move the macro list after $Type is declared.

Add optional prefixes to DECLARE_<FOO> and DEFINE_<BAR>
macro declarations to allow forms like:
	MLX4_DECLARE_DOORBELL_LOCK
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Dotan Barak <dotanb@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Checkpatch already complains when people break up quoted strings but
it's still pretty common.  One mistake that people often make is they
leave out the space character between the two strings.

This check adds around 450 new warnings and has a low rate of false
positives.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Andy Whitcroft <apw@canonical.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 89da401f6cff ("checkpatch: improve "no space after cast" test")
in -next improved the cast test for non pointer types, but also
introduced false positives for some types of static inlines.

Add a test for an open brace to the exclusions to avoid these false
positives.
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Hartley Sweeten <HartleyS@visionengravers.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Using --file mode can give false positives with MISSING_BREAK
fall-through warnings on simple but long multiple consecutive case
statements.

Look for all lines before a case statement for a switch or a statement
when using --file mode.

Fix a misspelling of preceded while there.
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

c90 section "6.7.2 Type Specifiers" says:
    "type specifiers may occur in any order"

That means that:
    short int is the same as int short
    unsigned short int is the same as int unsigned short
    etc...

checkpatch currently parses only a subset of these allowed types.

For instance: "unsigned short" and "signed short" are found by
checkpatch as a specific type, but none of the or "int short" or "int
signed short" variants are found.

Add another table for the "kernel style misordered" variants.

Add this misordered table to the findable types.

Warn when the misordered style is used.

This improves the "Missing a blank line after declarations" test as it
depends on the correct parsing of the $Declare variable which looks for
"$Type $Ident;" (ie: declarations like "int foo;").
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Current generic types are unsigned or unspecified.  Add signed to the
types.

Reorder the types to find the longest match first.
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

short int is one of the 6.7.2 c90 types.
Find it appropriately.

This fixes a defect in checkpatch where it suggests that a line break
after declaration is required using an input like:

	int foo;
	short int bar;

Without this change, it warns on the short int line.
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Hartley Sweeten <HartleyS@visionengravers.com>
Acked-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

All the various for_each loop macros were not tested for trailing brace
on the following lines and for bad indentation.

Add them.
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Greg KH <gregkh@linuxfoundation.org>
Cc: Andy Whitcroft <apw@canonical.com
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add --fix corrections for ELSE_AFTER_BRACE and WHILE_AFTER_BRACE
misuses.

	if (x) {
		...
	}
	else {
		...
	}

is corrected to

	if (x) {
		...
	} else {
		...
	}

and

	do {
		...
	}
	while (x);

is corrected to

	do {
		...
	} while (x);
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Style misuses of these types are corrected:

  typedef struct foo
  {
        int bar;
  };

  int foo(int bar) { return bar+1;
  }

  int foo(int bar) {
        return bar+1;
  }
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

I copied the which subroutine from get_maintainer.pl.

Unfortunately, get_maintainer uses a 4 space indentation so use the
proper tab indentation instead.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Neaten the uses of patch/file line insertions or deletions.  Hide the
mechanism used.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This can be valuable to insert or delete blank lines as well as fix
misplaced brace or else uses.

Store indexes of lines to be added/deleted and the new lines.

When creating the --fix file, insert or delete the appropriate lines and
update the patch range information.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Make the fix code a bit easier to read.

This should also start to allow an easier mechanism to insert/delete
lines eventually too.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Using break; after a goto or return is unnecessary so emit a warning
when the break is at the same indent level.

So this emits a warning on:

	switch (foo) {
	case 1:
		goto err;
		break;
	}

but not on:

	switch (foo) {
	case 1:
		if (bar())
			goto err;
		break;
	}
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Whenever files are added, moved, or deleted, the MAINTAINERS file
patterns can be out of sync or outdated.

To try to keep MAINTAINERS more up-to-date, add a one-time warning
whenever a patch does any of those.
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit logs have various forms of commit id references.

Try to standardize on a 12 character long lower case commit id along
with a description of parentheses and the quoted subject line.

ie: commit 0123456789ab ("commit description")

If git and a git tree exists, look up the commit id and emit the
appropriate line as part of the message.
Signed-off-by: Joe Perches <joe@perches.com>
Requested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Avoid matching allocs that appear to be known small multiplications of a
sizeof with a constant because gcc as of 4.8 cannot optimize the code in
a calloc() exactly the same way as an alloc().

Look for numeric constants or what appear to be upper case only macro
#defines.
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Theodore Ts'o <tytso@mit.edu>
Original-patch-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>