Add a case in cpu_probe_mips for the MIPS generic QEMU processor ID.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Add a CPU_QEMU_GENERIC case to various switch statements.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Latest versions of QEMU added support for mips32r6-generic and
mips64r6-generic cpu types so add related definitions in preparation
of MIPS R6 support. This is also used for QEMU R2 generic cpus.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
activate_mm() and switch_mm() call get_new_mmu_context() which in turn
can enable the HTW before the entryhi is changed with the new ASID.
Since the latter will enable the HTW in local_flush_tlb_all(),
then there is a small timing window where the HTW is running with the
new ASID but with an old pgd since the TLBMISS_HANDLER_SETUP_PGD
hasn't assigned a new one yet. In order to prevent that, we introduce a
simple htw counter to avoid starting HTW accidentally due to nested
htw_{start,stop}() sequences. Moreover, since various IPI calls can
enforce TLB flushing operations on a different core, such an operation
may interrupt another htw_{stop,start} in progress leading inconsistent
updates of the htw_seq variable. In order to avoid that, we disable the
interrupts whenever we update that variable.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org> # 3.17+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9118/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We need to check the ASEs support against the core's CFLAGS instead
of depending to the default -march option from the toolchain.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9180/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Whenever we modify a page table entry, we need to ensure that the HTW
will not fetch a stable entry. And for that to happen we need to ensure
that HTW is stopped before we modify the said entry otherwise the HTW
may already be in the process of reading that entry and fetching the
old information. As a result of which, we replace the htw_reset() calls
with htw_{stop,start} in more appropriate places. This also removes the
remaining users of htw_reset() and as a result we drop that macro
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org> # 3.17+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9116/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When we use htw_{start,stop}() outside of htw_reset(), we need
to ensure that c0 changes have been propagated properly before
we attempt to continue with subsequence memory operations.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org> # 3.17+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9114/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 41c594ab65 ("[MIPS] MT: Improved multithreading support.")
removed useful debug information for userland segmentation faults.
This patch bring this back along with the ability to determine the
name of the object file where the EPC and RA registers point at.
Furthermore, we select the SYSCTL_EXCEPTION_TRACE symbol for MIPS
which is the de facto solution to turn userland exception logging
on and off via the /proc/sys/debug/exception-trace file.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9089/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
DMA_PAUSE command is used for halting DMA transfer on chosen channel.
It can be useful when we want to safely read residue before terminating
all requests on channel. Otherwise there can be situation when some data
is transferred before channel termination but after reading residue,
which obviously results with data loss. To avoid this situation we can
pause channel, read residue and then terminate all requests.
This scenario is common, for example, in serial port drivers.
Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This patch adds possibility to read residue of DMA transfer. It's useful
when we want to know how many bytes have been transferred before we
terminate channel. It can take place, for example, on timeout interrupt.
Signed-off-by: Lukasz Czerwinski <l.czerwinski@samsung.com>
Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
A still unconfirmed hardware bug prevents the IPMMU microTLB 0 to be
flushed correctly, resulting in memory corruption. DMAC 0 channel 0 is
connected to microTLB 0 on currently supported platforms, so we can't
use it with the IPMMU. As the IOMMU API operates at the device level we
can't disable it selectively, so ignore channel 0 for now if the device
is part of an IOMMU group.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
When descriptor memory is accessed through an IOMMU the DMADAR register
isn't initialized automatically from the first descriptor at beginning
of transfer by the DMAC like it should. Initialize it manually with the
destination address of the first chunk.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
When wired to an IOMMU to access data, the DMAC accesses the hardware
descriptors through the IOMMU as well. We're using the DMA mapping API
to allocate the descriptors, but with a NULL device at the moment, which
prevents IOMMU mappings from being created. Fix this by passing the DMAC
device instead.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The error interrupt handler stops and reinitializes all channels. This
causes a crash for channels that have never been used, as their
descriptor lists are uninitialized. Fix it by initializing the
descriptor lists at probe time.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The rcar_dmac_desc_put() function is called in interrupt context and
must thus use spin_lock_irqsave() instead of spin_lock_irq().
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
this patch fixes following sparse warnings:
edma.c:537:32: warning: symbol 'edma_prep_dma_memcpy' was not declared. Should it be static?
edma.c:1070:6: warning: symbol 'edma_filter_fn' was not declared. Should it be static?
Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
two important bug fixes for radeon
* 'drm-next-3.20' of git://people.freedesktop.org/~agd5f/linux:
drm/radeon: fix voltage setup on hawaii
drm/radeon/dp: Set EDP_CONFIGURATION_SET for bridge chips if necessary
This modifies raid1's narrow_write_error to round up block_sectors to the
device's logical block size.
This prevents sd complaining about "Bad block number requested" for non-512-byte
sector disks.
Signed-off-by: Nate Dailey <nate.dailey@stratus.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If a request_key() call to allocate and fill out a key attempts to insert the
key structure into a revoked keyring, the key will leak, using memory and part
of the user's key quota until the system reboots. This is from a failure of
construct_alloc_key() to decrement the key's reference count after the attempt
to insert into the requested keyring is rejected.
key_put() needs to be called in the link_prealloc_failed callpath to ensure
the unused key is released.
Signed-off-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Recall all outstanding pNFS layouts and truncates, writes and similar extent
list modifying operations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Add operations to export pNFS block layouts from an XFS filesystem. See
the previous commit adding the operations for an explanation of them.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Instead of having various protocols provide <protocol>_supported()
functions, let's use IS_ENABLED() macro that works well in "if" statements.
Acked-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Introduce open and close methods for the input device to postpone enabling
the device until it is needed.
Acked-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Use of managed resources simplifies error handling.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Instead of using arch-specific accessors remap rotary register physical
address into kernel space in probe and use standard readw and writew to
access rotary MMRs.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Newer Blackfin boards use pinctrl API to manage pins and the legacy
peripherial lists are not useful on them. Let's move pin lists into
platform data so older boards can still use them and newer boards can use
the modern API.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The platform data definition of the rotary driver should be generic for all
architectures.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Instead of using #ifdef to guard potentially unused suspend and resume code
let's mark them as __maybe_unused so they still get discarded if they are
not used but we do not get warning. This allows for better compile coverage.
Acked-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The interrupt handler in the driver tries to fetch driver data from
platform device, unfortunately it is only set up after interrupt handler
is registered. Since interrupt handler does not really need to access
the platform device itself let's change it to get the driver data
instance instead.
Acked-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This patch move all packet info from driver source code to documentation
and adds info about v6 packet format (from driver source code).
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The comment about suspicions entry 0x20, 0x02, 0x0e has over time drifted
away and it become hard to figure out what it meant. Let's move it back so
it is clear.
Reported-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Previously dev2 device was used for both external PS/2 mouse and internal
trackstick device (if available). This change introduces dev3 device which
is used for external PS/2 mouse data and dev2 is now used only for
trackstick.
In case that trackstick is not present dev2 is not created, so userspace
does not see non existent device in system.
Because laptops with ALPS devices often do not use i8042 active
multiplexing all data (from touchpad, trackstick and external PS/2 mouse)
come to one port. So it is not possible to know if external PS/2 mouse is
connected or not. In most cases external PS/2 mouse is not connected so
driver will create dev3 input device after first bare PS/2 packet will be
received. So there will not be "ghost" input device.
This change also helps in identifying possible problems in future if driver
decides to report 6-bytes trackstick packets as 3-bytes bare PS/2 (data
will be reported to dev3 instead dev2).
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
On some Dell Latitudes we fail to identify presence of trackstick unless we
reset the device. The issue is quite benign as we do perform reset in
alps_init(), so the trackstick ends up working, but mouse name reported to
userspace is not accurate.
In order to fix the issue while avoiding the additional lengthy reset we
move the resrt to alps_detect() and keep the discovered state to be used
later in alps_init().
Reported-by: Pali Rohár <pali.rohar@gmail.com>
Tested-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Move setting of all protocol properties into alps_set_protocol (former
alps_set_defaults) instead of having it split between several functions.
Tested-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
In preparation of reworking the way we set protocol parameters let's
split certain protocol items from alps_model_info into a separate
structure.
Tested-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Even though Rushmore is very close to V3 protocol it is sufficiently
different to warrant it's own protocol name.
Tested-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
In order to accommodate new protocol number for Rushmore touchpads
let's shift protocol numbers by 8 bits (i.e. 1 -> 0x100) - this way
we keep protocol version reported in input device id the same as it
was, but add some holes in numbering.
Tested-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Here's the big tty/serial driver update for 3.20-rc1. Nothing huge
here, just lots of driver updates and some core tty layer fixes as well.
All have been in linux-next with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver patches from Greg KH:
"Here's the big tty/serial driver update for 3.20-rc1. Nothing huge
here, just lots of driver updates and some core tty layer fixes as
well. All have been in linux-next with no reported issues"
* tag 'tty-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (119 commits)
serial: 8250: Fix UART_BUG_TXEN workaround
serial: driver for ETRAX FS UART
tty: remove unused variable sprop
serial: of-serial: fetch line number from DT
serial: samsung: earlycon support depends on CONFIG_SERIAL_SAMSUNG_CONSOLE
tty/serial: serial8250_set_divisor() can be static
tty/serial: Add Spreadtrum sc9836-uart driver support
Documentation: DT: Add bindings for Spreadtrum SoC Platform
serial: samsung: remove redundant interrupt enabling
tty: Remove external interface for tty_set_termios()
serial: omap: Fix RTS handling
serial: 8250_omap: Use UPSTAT_AUTORTS for RTS handling
serial: core: Rework hw-assisted flow control support
tty/serial: 8250_early: Add support for PXA UARTs
tty/serial: of_serial: add support for PXA/MMP uarts
tty/serial: of_serial: add DT alias ID handling
serial: 8250: Prevent concurrent updates to shadow registers
serial: 8250: Use canary to restart console after suspend
serial: 8250: Refactor XR17V35X divisor calculation
serial: 8250: Refactor divisor programming
...
Here's the big staging driver tree update for 3.20-rc1. Lots of little
things in here, adding up to lots of overall cleanups. The IIO driver
updates are also in here as they cross the staging tree boundry a lot.
I2O has moved into staging as well, as a plan to drop it from the tree
eventually as that's a dead subsystem.
All of this has been in linux-next with no reported issues for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging drivers patches from Greg KH:
"Here's the big staging driver tree update for 3.20-rc1.
Lots of little things in here, adding up to lots of overall cleanups.
The IIO driver updates are also in here as they cross the staging tree
boundry a lot. I2O has moved into staging as well, as a plan to drop
it from the tree eventually as that's a dead subsystem.
All of this has been in linux-next with no reported issues for a
while"
* tag 'staging-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (740 commits)
staging: lustre: lustre: libcfs: define symbols as static
staging: rtl8712: Do coding style cleanup
staging: lustre: make obd_updatemax_lock static
staging: rtl8188eu: core: switch with redundant cases
staging: rtl8188eu: odm: conditional setting with no effect
staging: rtl8188eu: odm: condition with no effect
staging: ft1000: fix braces warning
staging: sm7xxfb: fix remaining CamelCase
staging: sm7xxfb: fix CamelCase
staging: rtl8723au: multiple condition with no effect - if identical to else
staging: sm7xxfb: make smtc_scr_info static
staging/lustre/mdc: Initialize req in mdc_enqueue for !it case
staging/lustre/clio: Do not allow group locks with gid 0
staging/lustre/llite: don't add to page cache upon failure
staging/lustre/llite: Add exception entry check after radix_tree
staging/lustre/libcfs: protect kkuc_groups from write access
staging/lustre/fld: refer to MDT0 for fld lookup in some cases
staging/lustre/llite: Solve a race to access lli_has_smd in read case
staging/lustre/ptlrpc: hold rq_lock when modify rq_flags
staging/lustre/lnet: portal spreading rotor should be unsigned
...
Really tiny set of patches for this kernel. Nothing major, all
described in the shortlog and have been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core patches from Greg KH:
"Really tiny set of patches for this kernel. Nothing major, all
described in the shortlog and have been in linux-next for a while"
* tag 'driver-core-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
sysfs: fix warning when creating a sysfs group without attributes
firmware_loader: handle timeout via wait_for_completion_interruptible_timeout()
firmware_loader: abort request if wait_for_completion is interrupted
firmware: Correct function name in comment
device: Change dev_<level> logging functions to return void
device: Fix dev_dbg_once macro
Here's the big char/misc driver update for 3.20-rc1.
Lots of little things in here, all described in the changelog. Nothing
major or unusual, except maybe the binder selinux stuff, which was all
acked by the proper selinux people and they thought it best to come
through this tree.
All of this has been in linux-next with no reported issues for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char / misc patches from Greg KH:
"Here's the big char/misc driver update for 3.20-rc1.
Lots of little things in here, all described in the changelog.
Nothing major or unusual, except maybe the binder selinux stuff, which
was all acked by the proper selinux people and they thought it best to
come through this tree.
All of this has been in linux-next with no reported issues for a while"
* tag 'char-misc-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (90 commits)
coresight: fix function etm_writel_cp14() parameter order
coresight-etm: remove check for unknown Kconfig macro
coresight: fixing CPU hwid lookup in device tree
coresight: remove the unnecessary function coresight_is_bit_set()
coresight: fix the debug AMBA bus name
coresight: remove the extra spaces
coresight: fix the link between orphan connection and newly added device
coresight: remove the unnecessary replicator property
coresight: fix the replicator subtype value
pdfdocs: Fix 'make pdfdocs' failure for 'uio-howto.tmpl'
mcb: Fix error path of mcb_pci_probe
virtio/console: verify device has config space
ti-st: clean up data types (fix harmless memory corruption)
mei: me: release hw from reset only during the reset flow
mei: mask interrupt set bit on clean reset bit
extcon: max77693: Constify struct regmap_config
extcon: adc-jack: Release IIO channel on driver remove
extcon: Remove duplicated include from extcon-class.c
Drivers: hv: vmbus: hv_process_timer_expiration() can be static
Drivers: hv: vmbus: serialize Offer and Rescind offer
...
Add an ->enter_freeze callback routine, acpi_idle_enter_freeze(), to
the ACPI cpuidle driver and point ->enter_freeze to it for all the
C2-type and C3-type states that don't need to fall back to C1
(which may be halt-induced and that will re-enable interrupts on
exit from idle, which ->enter_freeze cannot do).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Add an ->enter_freeze callback routine, intel_idle_freeze(), to
the intel_idle driver and point the ->enter_freeze callback
pointers of all of the driver's state objects to it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
The efficiency of suspend-to-idle depends on being able to keep CPUs
in the deepest available idle states for as much time as possible.
Ideally, they should only be brought out of idle by system wakeup
interrupts.
However, timer interrupts occurring periodically prevent that from
happening and it is not practical to chase all of the "misbehaving"
timers in a whack-a-mole fashion. A much more effective approach is
to suspend the local ticks for all CPUs and the entire timekeeping
along the lines of what is done during full suspend, which also
helps to keep suspend-to-idle and full suspend reasonably similar.
The idea is to suspend the local tick on each CPU executing
cpuidle_enter_freeze() and to make the last of them suspend the
entire timekeeping. That should prevent timer interrupts from
triggering until an IO interrupt wakes up one of the CPUs. It
needs to be done with interrupts disabled on all of the CPUs,
though, because otherwise the suspended clocksource might be
accessed by an interrupt handler which might lead to fatal
consequences.
Unfortunately, the existing ->enter callbacks provided by cpuidle
drivers generally cannot be used for implementing that, because some
of them re-enable interrupts temporarily and some idle entry methods
cause interrupts to be re-enabled automatically on exit. Also some
of these callbacks manipulate local clock event devices of the CPUs
which really shouldn't be done after suspending their ticks.
To overcome that difficulty, introduce a new cpuidle state callback,
->enter_freeze, that will be guaranteed (1) to keep interrupts
disabled all the time (and return with interrupts disabled) and (2)
not to touch the CPU timer devices. Modify cpuidle_enter_freeze() to
look for the deepest available idle state with ->enter_freeze present
and to make the CPU execute that callback with suspended tick (and the
last of the online CPUs to execute it with suspended timekeeping).
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
