Commit Graph

54654 Commits

Author SHA1 Message Date
Olof Johansson
5589d62484 Merge tag 'qcom-drivers-for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/agross/linux into next/drivers
Qualcomm ARM Based Driver Updates for v4.10

* Fixup QCOM SCM to use devm_reset_controller_register
* Add QCOM pinctrl to Qualcomm MAINTAINERS entry
* Add PM8994 regulator definitions
* Add stub for WCNSS_CTRL API

* tag 'qcom-drivers-for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/agross/linux:
  firmware: qcom: scm: Use devm_reset_controller_register()
  MAINTAINERS: add drivers/pinctrl/qcom to ARM/QUALCOMM SUPPORT
  pinctrl: pm8994: add pad voltage regulator defines
  soc: qcom: wcnss_ctrl: Stub wcnss_ctrl API

Signed-off-by: Olof Johansson <olof@lixom.net>
2016-11-17 23:38:27 -08:00
Johannes Thumshirn
a0f4bd7f2a scsi: fc: move FC transport's bsg code to bsg-lib
Now that all conversions are done, move the FibreChannel bsg code over
to the bsg library.

This patch is derived from work done by Mike Christie in 2011 [1] but
only the iscsi parts got merged back then.

[1] http://marc.info/?l=linux-scsi&m=131149780921009&w=2

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-17 20:15:26 -05:00
Johannes Thumshirn
fb6f7c8d8a block: add bsg_job_put() and bsg_job_get()
Add bsg_job_put() and bsg_job_get() so don't need to export
bsg_destroy_job() any more.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-17 20:15:26 -05:00
Johannes Thumshirn
6aa858cd33 scsi: fc: use bsg_softirq_done
bsg_softirq_done() and fc_bsg_softirq_done() are copies of each other, so
ditch the fc specific one.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-17 20:15:26 -05:00
Johannes Thumshirn
c00da4c90f scsi: fc: Use bsg_destroy_job
fc_destroy_bsgjob() and bsg_destroy_job() are now 1:1 copies, so use the
latter. As bsg_destroy_job() comes from bsg-lib we need to select it in
Kconfig once CONFOG_SCSI_FC_ATTRS is active.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-17 20:15:25 -05:00
Johannes Thumshirn
bf0f2d380f block: add reference counting for struct bsg_job
Add reference counting to 'struct bsg_job' so we can implement a reuqest
timeout handler for bsg_jobs, which is needed for Fibre Channel.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-17 20:15:25 -05:00
Lukas Wunner
437eb7bf7b ACPI / hotplug / PCI: Make device_is_managed_by_native_pciehp() public
We're about to add runtime PM of hotplug ports, but we need to restrict it
to ports that are handled natively by the OS:  If they're handled by the
firmware (which is the case for Thunderbolt on non-Macs), things would
break if the OS put the ports into D3hot behind the firmware's back.

To determine if a hotplug port is handled natively, one has to walk up from
the port to the root bridge and check the cached _OSC Control Field for the
value of the "PCI Express Native Hot Plug control" bit.  There's already a
function to do that, device_is_managed_by_native_pciehp(), but it's private
to drivers/pci/hotplug/acpiphp_glue.c and only compiled in if
CONFIG_HOTPLUG_PCI_ACPI is enabled.

Make it public and move it to drivers/pci/pci-acpi.c, so that it is
available in the more general CONFIG_ACPI case.

The function contains a check if the device in question is a hotplug port
and returns false if it's not.  The caller we're going to add doesn't need
this as it only calls the function if it actually *is* a hotplug port.
Move the check out of the function into the single existing caller.

Rename it to pciehp_is_native() and add some kerneldoc and polish.

No functional change intended.

Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-17 18:47:58 -06:00
Vadim Pasternak
c02b7bf532 i2c: mux: mellanox: add driver
This driver allows I2C routing controlled through CPLD select registers on
a wide range of Mellanox systems (CPLD Lattice device).
MUX selection is provided by digital and analog HW. Analog part is not
under SW control.
Digital part is under CPLD control (channel selection/de-selection).

Connectivity schema.
.---.             .-------------.
| l |             |             |-- i2cx1 -- i2cx8
| i |-- i2cn --+--| mlxcpld mux |
| n |          |  |             |-- i2cy1 -- i2cy8
| u |          |  '-------------'
| x |          |         |
'---'          '---------'

i2c-mux-mlxpcld does not necessarily require i2c-mlxcpld. It can be used
along with another bus driver, and still control i2c routing through CPLD
mux selection, in case the system is equipped with CPLD capable of mux
selection control.

The Kconfig currently controlling compilation of this code is:
drivers/i2c/muxes/Kconfig:config I2C_MUX_MLXCPLD

Signed-off-by: Michael Shych <michaelsh@mellanox.com>
Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-17 23:19:00 +01:00
Noa Osherovich
7254383341 PCI: Add Mellanox device IDs
Add Mellanox device IDs for use by the mlx4 driver and INTx quirks.

[bhelgaas: sorted and adapted from
http://lkml.kernel.org/r/1478011644-12080-1-git-send-email-noaos@mellanox.com]
Signed-off-by: Noa Osherovich <noaos@mellanox.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-11-17 16:06:56 -06:00
Stephen Boyd
54fd1b3bc4 Merge tag 'clk-renesas-for-v4.10-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers into clk-next
Pull Renesas clk driver updates from Geerty Uytterhoeven:

  - Add R-Car RST driver for obtaining mode pin state, and move the
    related functionality from platform code to DT,
  - Add r8a7743 and r8a7745 CPG Core Clock Definitions.

The commits here are intermingled with arm-soc material because
of the hard dependency we're breaking between mach code and
driver code. We're replacing that with a driver dependency
between the soc driver and the clk driver.

* tag 'clk-renesas-for-v4.10-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers: (25 commits)
  clk: renesas: Add r8a7745 CPG Core Clock Definitions
  clk: renesas: Add r8a7743 CPG Core Clock Definitions
  clk: renesas: rcar-gen2: Remove obsolete rcar_gen2_clocks_init()
  clk: renesas: r8a7779: Remove obsolete r8a7779_clocks_init()
  clk: renesas: r8a7778: Remove obsolete r8a7778_clocks_init()
  ARM: shmobile: rcar-gen2: Stop passing mode pins state to clock driver
  ARM: shmobile: r8a7779: Stop passing mode pins state to clock driver
  ARM: shmobile: r8a7778: Stop passing mode pins state to clock driver
  clk: renesas: rcar-gen3-cpg: Remove obsolete rcar_gen3_read_mode_pins()
  clk: renesas: r8a7796: Obtain mode pin values from R-Car RST driver
  clk: renesas: r8a7795: Obtain mode pin values from R-Car RST driver
  clk: renesas: rcar-gen2: Obtain mode pin values using RST driver
  clk: renesas: r8a7779: Obtain mode pin values from R-Car RST driver
  clk: renesas: r8a7778: Obtain mode pin values using R-Car RST driver
  arm64: renesas: r8a7796 dtsi: Add device node for RST module
  arm64: renesas: r8a7795 dtsi: Add device node for RST module
  ARM: dts: r8a7794: Add device node for RST module
  ARM: dts: r8a7793: Add device node for RST module
  ARM: dts: r8a7792: Add device node for RST module
  ARM: dts: r8a7791: Add device node for RST module
  ...
2016-11-17 13:31:07 -08:00
Jens Axboe
64f1c21e86 blk-mq: make the polling code adaptive
The previous commit introduced the hybrid sleep/poll mode. Take
that one step further, and use the completion latencies to
automatically sleep for half the mean completion time. This is
a good approximation.

This changes the 'io_poll_delay' sysfs file a bit to expose the
various options. Depending on the value, the polling code will
behave differently:

-1	Never enter hybrid sleep mode
 0	Use half of the completion mean for the sleep delay
>0	Use this specific value as the sleep delay

Signed-off-by: Jens Axboe <axboe@fb.com>
Tested-By: Stephen Bates <sbates@raithlin.com>
Reviewed-By: Stephen Bates <sbates@raithlin.com>
2016-11-17 13:34:57 -07:00
Jens Axboe
06426adf07 blk-mq: implement hybrid poll mode for sync O_DIRECT
This patch enables a hybrid polling mode. Instead of polling after IO
submission, we can induce an artificial delay, and then poll after that.
For example, if the IO is presumed to complete in 8 usecs from now, we
can sleep for 4 usecs, wake up, and then do our polling. This still puts
a sleep/wakeup cycle in the IO path, but instead of the wakeup happening
after the IO has completed, it'll happen before. With this hybrid
scheme, we can achieve big latency reductions while still using the same
(or less) amount of CPU.

Signed-off-by: Jens Axboe <axboe@fb.com>
Tested-By: Stephen Bates <sbates@raithlin.com>
Reviewed-By: Stephen Bates <sbates@raithlin.com>
2016-11-17 13:34:51 -07:00
Aaron Lu
5d1904204c mremap: fix race between mremap() and page cleanning
Prior to 3.15, there was a race between zap_pte_range() and
page_mkclean() where writes to a page could be lost.  Dave Hansen
discovered by inspection that there is a similar race between
move_ptes() and page_mkclean().

We've been able to reproduce the issue by enlarging the race window with
a msleep(), but have not been able to hit it without modifying the code.
So, we think it's a real issue, but is difficult or impossible to hit in
practice.

The zap_pte_range() issue is fixed by commit 1cf35d47712d("mm: split
'tlb_flush_mmu()' into tlb flushing and memory freeing parts").  And
this patch is to fix the race between page_mkclean() and mremap().

Here is one possible way to hit the race: suppose a process mmapped a
file with READ | WRITE and SHARED, it has two threads and they are bound
to 2 different CPUs, e.g.  CPU1 and CPU2.  mmap returned X, then thread
1 did a write to addr X so that CPU1 now has a writable TLB for addr X
on it.  Thread 2 starts mremaping from addr X to Y while thread 1
cleaned the page and then did another write to the old addr X again.
The 2nd write from thread 1 could succeed but the value will get lost.

        thread 1                           thread 2
     (bound to CPU1)                    (bound to CPU2)

  1: write 1 to addr X to get a
     writeable TLB on this CPU

                                        2: mremap starts

                                        3: move_ptes emptied PTE for addr X
                                           and setup new PTE for addr Y and
                                           then dropped PTL for X and Y

  4: page laundering for N by doing
     fadvise FADV_DONTNEED. When done,
     pageframe N is deemed clean.

  5: *write 2 to addr X

                                        6: tlb flush for addr X

  7: munmap (Y, pagesize) to make the
     page unmapped

  8: fadvise with FADV_DONTNEED again
     to kick the page off the pagecache

  9: pread the page from file to verify
     the value. If 1 is there, it means
     we have lost the written 2.

  *the write may or may not cause segmentation fault, it depends on
  if the TLB is still on the CPU.

Please note that this is only one specific way of how the race could
occur, it didn't mean that the race could only occur in exact the above
config, e.g. more than 2 threads could be involved and fadvise() could
be done in another thread, etc.

For anonymous pages, they could race between mremap() and page reclaim:
THP: a huge PMD is moved by mremap to a new huge PMD, then the new huge
PMD gets unmapped/splitted/pagedout before the flush tlb happened for
the old huge PMD in move_page_tables() and we could still write data to
it.  The normal anonymous page has similar situation.

To fix this, check for any dirty PTE in move_ptes()/move_huge_pmd() and
if any, did the flush before dropping the PTL.  If we did the flush for
every move_ptes()/move_huge_pmd() call then we do not need to do the
flush in move_pages_tables() for the whole range.  But if we didn't, we
still need to do the whole range flush.

Alternatively, we can track which part of the range is flushed in
move_ptes()/move_huge_pmd() and which didn't to avoid flushing the whole
range in move_page_tables().  But that would require multiple tlb
flushes for the different sub-ranges and should be less efficient than
the single whole range flush.

KBuild test on my Sandybridge desktop doesn't show any noticeable change.
v4.9-rc4:
  real    5m14.048s
  user    32m19.800s
  sys     4m50.320s

With this commit:
  real    5m13.888s
  user    32m19.330s
  sys     4m51.200s

Reported-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-17 09:46:56 -08:00
Alexander Usyskin
7c7a6077f5 mei: bus: split RX and async notification callbacks
Split callbacks for RX and async notification events on mei bus to
eliminate synchronization problems and to open way for RX optimizations.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-17 16:37:49 +01:00
Kirti Wankhede
c747f08aea vfio: Introduce vfio_set_irqs_validate_and_prepare()
Vendor driver using mediated device framework would use same mechnism to
validate and prepare IRQs. Introducing this function to reduce code
replication in multiple drivers.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-11-17 08:33:20 -07:00
Kirti Wankhede
b3c0a866f1 vfio: Introduce common function to add capabilities
Vendor driver using mediated device framework should use
vfio_info_add_capability() to add capabilities.
Introduced this function to reduce code duplication in vendor drivers.

vfio_info_cap_shift() manipulated a data buffer to add an offset to each
element in a chain. This data buffer is documented in a uapi header.
Changing vfio_info_cap_shift symbol to be available to all drivers.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-11-17 08:33:20 -07:00
Kirti Wankhede
c086de818d vfio iommu: Add blocking notifier to notify DMA_UNMAP
Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
about DMA_UNMAP.
Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
Notifier should be registered, if external user wants to use
vfio_pin_pages()/vfio_unpin_pages() APIs to pin/unpin pages.
Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
mappings.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-11-17 08:33:07 -07:00
Kirti Wankhede
2169037dc3 vfio iommu: Added pin and unpin callback functions to vfio_iommu_driver_ops
Added APIs for pining and unpining set of pages. These call back into
backend iommu module to actually pin and unpin pages.
Added two new callback functions to struct vfio_iommu_driver_ops. Backend
IOMMU module that supports pining and unpinning pages for mdev devices
should provide these functions.

Renamed static functions in vfio_type1_iommu.c to resolve conflicts

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-11-17 08:24:58 -07:00
Kirti Wankhede
7b96953bc6 vfio: Mediated device Core driver
Design for Mediated Device Driver:
Main purpose of this driver is to provide a common interface for mediated
device management that can be used by different drivers of different
devices.

This module provides a generic interface to create the device, add it to
mediated bus, add device to IOMMU group and then add it to vfio group.

Below is the high Level block diagram, with Nvidia, Intel and IBM devices
as example, since these are the devices which are going to actively use
this module as of now.

 +---------------+
 |               |
 | +-----------+ |  mdev_register_driver() +--------------+
 | |           | +<------------------------+ __init()     |
 | |  mdev     | |                         |              |
 | |  bus      | +------------------------>+              |<-> VFIO user
 | |  driver   | |     probe()/remove()    | vfio_mdev.ko |    APIs
 | |           | |                         |              |
 | +-----------+ |                         +--------------+
 |               |
 |  MDEV CORE    |
 |   MODULE      |
 |   mdev.ko     |
 | +-----------+ |  mdev_register_device() +--------------+
 | |           | +<------------------------+              |
 | |           | |                         |  nvidia.ko   |<-> physical
 | |           | +------------------------>+              |    device
 | |           | |        callback         +--------------+
 | | Physical  | |
 | |  device   | |  mdev_register_device() +--------------+
 | | interface | |<------------------------+              |
 | |           | |                         |  i915.ko     |<-> physical
 | |           | +------------------------>+              |    device
 | |           | |        callback         +--------------+
 | |           | |
 | |           | |  mdev_register_device() +--------------+
 | |           | +<------------------------+              |
 | |           | |                         | ccw_device.ko|<-> physical
 | |           | +------------------------>+              |    device
 | |           | |        callback         +--------------+
 | +-----------+ |
 +---------------+

Core driver provides two types of registration interfaces:
1. Registration interface for mediated bus driver:

/**
  * struct mdev_driver - Mediated device's driver
  * @name: driver name
  * @probe: called when new device created
  * @remove:called when device removed
  * @driver:device driver structure
  *
  **/
struct mdev_driver {
         const char *name;
         int  (*probe)  (struct device *dev);
         void (*remove) (struct device *dev);
         struct device_driver    driver;
};

Mediated bus driver for mdev device should use this interface to register
and unregister with core driver respectively:

int  mdev_register_driver(struct mdev_driver *drv, struct module *owner);
void mdev_unregister_driver(struct mdev_driver *drv);

Mediated bus driver is responsible to add/delete mediated devices to/from
VFIO group when devices are bound and unbound to the driver.

2. Physical device driver interface
This interface provides vendor driver the set APIs to manage physical
device related work in its driver. APIs are :

* dev_attr_groups: attributes of the parent device.
* mdev_attr_groups: attributes of the mediated device.
* supported_type_groups: attributes to define supported type. This is
			 mandatory field.
* create: to allocate basic resources in vendor driver for a mediated
         device. This is mandatory to be provided by vendor driver.
* remove: to free resources in vendor driver when mediated device is
         destroyed. This is mandatory to be provided by vendor driver.
* open: open callback of mediated device
* release: release callback of mediated device
* read : read emulation callback.
* write: write emulation callback.
* ioctl: ioctl callback.
* mmap: mmap emulation callback.

Drivers should use these interfaces to register and unregister device to
mdev core driver respectively:

extern int  mdev_register_device(struct device *dev,
                                 const struct parent_ops *ops);
extern void mdev_unregister_device(struct device *dev);

There are no locks to serialize above callbacks in mdev driver and
vfio_mdev driver. If required, vendor driver can have locks to serialize
above APIs in their driver.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Reviewed-by: Jike Song <jike.song@intel.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-11-17 08:24:48 -07:00
Lee Jones
b8a1a4cd5a i2c: Provide a temporary .probe_new() call-back type
This will aid the seamless removal of the current probe()'s, more
commonly unused than used second parameter.  Most I2C drivers can
simply switch over to the new interface, others which have DT
support can use its own matching instead and others can call
i2c_match_id() themselves.  This brings I2C's device probe method
into line with other similar interfaces in the kernel and prevents
the requirement to pass an i2c_device_id table.

Suggested-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
[Kieran: fix rebase conflicts and adapt for dev_pm_domain_{attach,detach}]
Tested-by: Kieran Bingham <kieran@bingham.xyz>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-17 16:10:23 +01:00
Lee Jones
5f441fcaa3 i2c: Export i2c_match_id() for direct use by device drivers
When there was no other way to match a I2C device to driver i2c_match_id()
was exclusively used.  However, now there are other types of tables which
are commonly supplied, matching on an i2c_device_id table is used less
frequently.  Instead of _always_ calling i2c_match_id() from within the
framework, we only need to do so from drivers which have no other way of
matching.  This patch makes i2c_match_id() available to the aforementioned
device drivers.

Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Tested-by: Kieran Bingham <kieran@bingham.xyz>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-17 16:10:22 +01:00
Lee Jones
298d4de1ed i2c: Match using traditional OF methods, then by vendor-less compatible strings
This function provides a single call for all I2C devices which need to
match firstly using traditional OF means i.e by of_node, then if that
fails we attempt to match using the supplied I2C client name with a
list of supplied compatible strings with the '<vendor>,' string
removed.  The latter is required due to the unruly naming conventions
used currently by I2C devices.

Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
[Kieran: Fix static inline usage on !CONFIG_OF]
Tested-by: Kieran Bingham <kieran@bingham.xyz>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-17 16:10:20 +01:00
Seth Forshee
f97df70b1c xenfs: Use proc_create_mount_point() to create /proc/xen
Mounting proc in user namespace containers fails if the xenbus
filesystem is mounted on /proc/xen because this directory fails
the "permanently empty" test. proc_create_mount_point() exists
specifically to create such mountpoints in proc but is currently
proc-internal. Export this interface to modules, then use it in
xenbus when creating /proc/xen.

Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2016-11-17 13:52:18 +01:00
Sylwester Nawrocki
c41668ad5d ARM: s3c64xx: Drop unused DMA fields from struct s3c64xx_spi_csinfo
There is no drivers using those fields so remove them and
the remaining initializations.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-11-17 15:51:29 +05:30
Sylwester Nawrocki
da6f8ca13f dmaengine: pl08x: Add support for the DMA slave map
This patch adds support for the new channel request API introduced
in commit a8135d0d79
"dmaengine: core: Introduce new, universal API to request a channel".

param field of struct dma_slave_map type entries in the platform
data structure should be pointing to struct pl08x_channel_data
of related DMA channel.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-11-17 15:51:28 +05:30
Christian Borntraeger
6d0d287891 locking/core: Provide common cpu_relax_yield() definition
No need to duplicate the same define everywhere. Since
the only user is stop-machine and the only provider is
s390, we can use a default implementation of cpu_relax_yield()
in sched.h.

Suggested-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-s390 <linux-s390@vger.kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1479298985-191589-1-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-17 08:17:36 +01:00
Bjorn Andersson
f88536f1a5 Merge branch 'topic/st_fdma' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/slave-dma into rproc-next 2016-11-16 22:19:47 -08:00
Eric Dumazet
89c4b442b7 netpoll: more efficient locking
Callers of netpoll_poll_lock() own NAPI_STATE_SCHED

Callers of netpoll_poll_unlock() have BH blocked between
the NAPI_STATE_SCHED being cleared and poll_lock is released.

We can avoid the spinlock which has no contention, and use cmpxchg()
on poll_owner which we need to set anyway.

This removes a possible lockdep violation after the cited commit,
since sk_busy_loop() re-enables BH before calling busy_poll_stop()

Fixes: 217f697436 ("net: busy-poll: allow preemption in sk_busy_loop()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-16 18:32:02 -05:00
Longpeng \(Mike\)
c139c6b7b7 ACPI / tebles: remove redundant declare of acpi_table_parse_entries()
This function declared twice, so remove one declaration of it.

Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-16 22:38:25 +01:00
Mauro Carvalho Chehab
36f94a5cf0 Merge tag 'v4.9-rc5' into patchwork
Linux 4.9-rc5

* tag 'v4.9-rc5': (1102 commits)
  Linux 4.9-rc5
  gp8psk: Fix DVB frontend attach
  gp8psk: fix gp8psk_usb_in_op() logic
  dvb-usb: move data_mutex to struct dvb_usb_device
  iio: maxim_thermocouple: detect invalid storage size in read()
  aoe: fix crash in page count manipulation
  lightnvm: invalid offset calculation for lba_shift
  Kbuild: enable -Wmaybe-uninitialized warnings by default
  pcmcia: fix return value of soc_pcmcia_regulator_set
  infiniband: shut up a maybe-uninitialized warning
  crypto: aesni: shut up -Wmaybe-uninitialized warning
  rc: print correct variable for z8f0811
  dib0700: fix nec repeat handling
  s390: pci: don't print uninitialized data for debugging
  nios2: fix timer initcall return value
  x86: apm: avoid uninitialized data
  NFSv4.1: work around -Wmaybe-uninitialized warning
  Kbuild: enable -Wmaybe-uninitialized warning for "make W=1"
  lib/stackdepot: export save/fetch stack for drivers
  mm: kmemleak: scan .data.ro_after_init
  ...
2016-11-16 16:42:27 -02:00
Eric Dumazet
364b605573 net: busy-poll: return busypolling status to drivers
NAPI drivers use napi_complete_done() or napi_complete() when
they drained RX ring and right before re-enabling device interrupts.

In busy polling, we can avoid interrupts being delivered since
we are polling RX ring in a controlled loop.

Drivers can chose to use napi_complete_done() return value
to reduce interrupts overhead while busy polling is active.

This is optional, legacy drivers should work fine even
if not updated.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Adam Belay <abelay@google.com>
Cc: Tariq Toukan <tariqt@mellanox.com>
Cc: Yuval Mintz <Yuval.Mintz@cavium.com>
Cc: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-16 13:40:58 -05:00
Eric Dumazet
217f697436 net: busy-poll: allow preemption in sk_busy_loop()
After commit 4cd13c21b2 ("softirq: Let ksoftirqd do its job"),
sk_busy_loop() needs a bit of care :
softirqs might be delayed since we do not allow preemption yet.

This patch adds preemptiom points in sk_busy_loop(),
and makes sure no unnecessary cache line dirtying
or atomic operations are done while looping.

A new flag is added into napi->state : NAPI_STATE_IN_BUSY_POLL

This prevents napi_complete_done() from clearing NAPIF_STATE_SCHED,
so that sk_busy_loop() does not have to grab it again.

Similarly, netpoll_poll_lock() is done one time.

This gives about 10 to 20 % improvement in various busy polling
tests, especially when many threads are busy polling in
configurations with large number of NIC queues.

This should allow experimenting with bigger delays without
hurting overall latencies.

Tested:
 On a 40Gb mlx4 NIC, 32 RX/TX queues.

 echo 70 >/proc/sys/net/core/busy_read
 for i in `seq 1 40`; do echo -n $i: ; ./super_netperf $i -H lpaa24 -t UDP_RR -- -N -n; done

    Before:      After:
 1:   90072   92819
 2:  157289  184007
 3:  235772  213504
 4:  344074  357513
 5:  394755  458267
 6:  461151  487819
 7:  549116  625963
 8:  544423  716219
 9:  720460  738446
10:  794686  837612
11:  915998  923960
12:  937507  925107
13: 1019677  971506
14: 1046831 1113650
15: 1114154 1148902
16: 1105221 1179263
17: 1266552 1299585
18: 1258454 1383817
19: 1341453 1312194
20: 1363557 1488487
21: 1387979 1501004
22: 1417552 1601683
23: 1550049 1642002
24: 1568876 1601915
25: 1560239 1683607
26: 1640207 1745211
27: 1706540 1723574
28: 1638518 1722036
29: 1734309 1757447
30: 1782007 1855436
31: 1724806 1888539
32: 1717716 1944297
33: 1778716 1869118
34: 1805738 1983466
35: 1815694 2020758
36: 1893059 2035632
37: 1843406 2034653
38: 1888830 2086580
39: 1972827 2143567
40: 1877729 2181851

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Adam Belay <abelay@google.com>
Cc: Tariq Toukan <tariqt@mellanox.com>
Cc: Yuval Mintz <Yuval.Mintz@cavium.com>
Cc: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-16 13:40:57 -05:00
Josef Bacik
f23cc643f9 bpf: fix range arithmetic for bpf map access
I made some invalid assumptions with BPF_AND and BPF_MOD that could result in
invalid accesses to bpf map entries.  Fix this up by doing a few things

1) Kill BPF_MOD support.  This doesn't actually get used by the compiler in real
life and just adds extra complexity.

2) Fix the logic for BPF_AND, don't allow AND of negative numbers and set the
minimum value to 0 for positive AND's.

3) Don't do operations on the ranges if they are set to the limits, as they are
by definition undefined, and allowing arithmetic operations on those values
could make them appear valid when they really aren't.

This fixes the testcase provided by Jann as well as a few other theoretical
problems.

Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-16 13:21:45 -05:00
Hans Verkuil
0dbacebede [media] cec: move the CEC framework out of staging and to media
The last open issues have been addressed, so it is time to move
this out of staging and into the mainline and to move the public
cec headers to include/uapi/linux.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-11-16 15:40:20 -02:00
Hans Verkuil
a69a168a1b [media] cec: add proper support for CDC-Only CEC devices
CDC-Only CEC devices are CEC devices that can only handle CDC messages,
all other messages are ignored.

Add a flag to signal that this is a CDC-Only device and act accordingly.

Also add helper functions to identify if a CEC device is configured as a
CDC-Only device, a second TV, a switch or a processor, since these variations
cannot be determined by the logical address alone.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-11-16 15:36:03 -02:00
Hans Verkuil
adc0c62278 [media] cec: add CEC_MSG_FL_REPLY_TO_FOLLOWERS
Give the caller more control over how replies to a transmit are
handled. By default the reply will only go to the filehandle that
called CEC_TRANSMIT. If this new flag is set, then the reply will
also go to all followers.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-11-16 15:32:56 -02:00
Hans Verkuil
f4062625ed [media] cec: add flag to cec_log_addrs to enable RC passthrough
By default the CEC_MSG_USER_CONTROL_PRESSED/RELEASED messages
are passed on to the follower(s) only. If the new
CEC_LOG_ADDRS_FL_ALLOW_RC_PASSTHRU flag is set in the
flags field of struct cec_log_addrs then these messages are also
passed on to the remote control input subsystem and they will appear
as keystrokes.

This used to be the default behavior, but now you have to explicitly
enable it. This is done to force the caller to think about possible
security issues (e.g. if these messages are used to enter passwords).

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-11-16 15:32:07 -02:00
Greg Kroah-Hartman
2c52b1efd6 Merge tag 'iio-for-4.10c' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next
Jonathan writes:

Third set of IIO new device support, features and cleanup for the 4.10 cycle.

Includes Peter Rosin's interesting drivers for a comparator. First complex
use we have had with an analog front end made from discrete components.

Brian Masney's work on moving the tsl2583 driver out of staging also
feature extensively!

New Drivers
* DAC based on a digital potentiometer
  - New driver for the use of a dpot as a DAC. Includes bindings and Axentia
  entry in vendor prefixes.
* Envelope detector baed on DAC and a comparator including device tree
  bindings.

Staging Graduation
* tsl2583.

Core new features
- Core provision for _available attributes.   This one had been stalled for
  a long time until Peter picked it up and ran with it!
- In kernel interface helpers to retrieve available info from channels.

Driver new features
* mcp4531
  - Add range of available raw values (used for the dpot dac driver).

Driver cleanups and fixes for issues introduced
* ad7766
  - Testing the wrong variable following devm_regulator_bulk_get introduced
  with the driver earlier in this cycle.
* ad9832
  - Fix a wrong ordering in the probe introduced in the previous set of
    patches.  A use before allocation bug.
* cros_ec_sensors
  - Testing for an error in a u8 will never work.
* mpu3050
  - Remove duplicate initializer for the module owner.
  - Add missing i2c dependency.
  - Inform the i2c mux core how it is used - step one in implifying device
  tree bindings.
* st-sensors
  - Get rid of large number of uninformative defines in favour of putting the
  constants where they are relevant. It is clear what they are from where
  they are used.
* tsl2583
  - Fix unused function warning when CONFIG_PM disabled and remove the
  ifdefs in favour of __maybe_unused.
  - Refactor taos_chip_on  to only read relevant registers.
  - Make sure calibscale and integration time are being set.
  - Verify chip is in ready to be used before calibration.
  - Remove some repeated checks for chip status (it's protected by a mutex
  so can't change until it's released)
  - Change current state storage from a tristate enum to a boolean seeing as
  only two values are actually used now.
  - Drop a redundant write to the control regiser in taos_probe (it's a noop)
  - Drop the FSF mailing address.
  - Clean up logging to not use hard coded function names (use __func__
  instead).
  - Cleanup up variable and function name prefixes.
  - Alignment of #define fixes.
  - Fix comparison between signed and unsigned integer warnings.
  - Add some newlines in favour of readability.
  - Combine the two sysfs ABI docs that somehow ended up in different places.
  - Fix multiline comment syntax.
  - Move a code block to inside an else statement as it makes more sense there.
  - Change tsl2583_als_calibrate to return 0 rather than a value nothing
  reads.
  - Drop some pointless brackets
  - Don't assume 32bit unsigned int.
  - Change to a per device instance lux table.
  - Add missing tsl2583 to the list of supported devices in the intro comments.
  - Improve commment on clearing of interrupts.
  - Drop some uninformative comments.
  - Drop a memset call that doesn't do anything useful any more.
  - Don't initialize some return variables that are always set.
  - Add Brian Masney as a module author after all these changes.
2016-11-16 17:20:40 +01:00
Thomas Gleixner
7ce7f35b33 Merge branch 'x86/cpufeature' into x86/cache
Resolve the cpu/scattered conflict.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 14:19:34 +01:00
Ed Blake
db405a8f8b serial: 8250: Expose set_ldisc function
Expose set_ldisc() function so that it can be overridden with a
platform specific implementation.

Signed-off-by: Ed Blake <ed.blake@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-16 10:59:38 +01:00
Ed Blake
98838d9507 serial: 8250: Add IrDA to UART capabilities
Add an IrDA UART capability flag and change the type of
uart_8250_port.capabilities to be u32 rather than unsigned short to
accommodate the additional flag.

Signed-off-by: Ed Blake <ed.blake@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-16 10:59:38 +01:00
Ingo Molnar
43496d3551 locking/mutex: Don't mark mutex_trylock_recursive() as deprecated, temporarily
Until the DRM drivers are fixed to not use mutex_trylock_recursive(),
allyes/modconfig builds will emit an API deprecation warning:

 drivers/gpu/drm/i915/i915_gem_shrinker.c: In function ‘i915_gem_shrinker_lock’:
 drivers/gpu/drm/i915/i915_gem_shrinker.c:230:2: warning: ‘mutex_trylock_recursive’ is deprecated [-Wdeprecated-declarations]
   switch (mutex_trylock_recursive(&dev->struct_mutex)) {
	    ^

Don't pollute the kernel log until the DRM code is fixed. Hopefully
the checkpatch warning is enough to keep people from using this new
API, and we'll be NAK-ing new users as well.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Ding Tianhong <dingtianhong@huawei.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Jason Low <jason.low2@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Terry Rudd <terry.rudd@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Will Deacon <Will.Deacon@arm.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:39:43 +01:00
Ingo Molnar
0acbc7aa47 Merge branch 'linus' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:16:28 +01:00
Sebastian Andrzej Siewior
0e285d36bd x86/mcheck: Move CPU_DEAD to hotplug state machine
This moves the last piece of the old hotplug notifier code in MCE to the
new hotplug state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: rt@linutronix.de
Cc: linux-edac@vger.kernel.org
Link: http://lkml.kernel.org/r/20161110174447.11848-8-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 09:34:18 +01:00
Nicolas Pitre
74ba181e61 timer: Move sys_alarm from timer.c to itimer.c
Move the only user of alarm_setitimer to itimer.c where it is defined.
This allows for making alarm_setitimer static, and dropping it from the
build when __ARCH_WANT_SYS_ALARM is not defined.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: linux-kbuild@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Edward Cree <ecree@solarflare.com>
Link: http://lkml.kernel.org/r/1478841010-28605-5-git-send-email-nicolas.pitre@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 09:26:34 +01:00
Nicolas Pitre
d1cbfd771c ptp_clock: Allow for it to be optional
In order to break the hard dependency between the PTP clock subsystem and
ethernet drivers capable of being clock providers, this patch provides
simple PTP stub functions to allow linkage of those drivers into the
kernel even when the PTP subsystem is configured out. Drivers must be
ready to accept NULL from ptp_clock_register() in that case.

And to make it possible for PTP to be configured out, the select statement
in those driver's Kconfig menu entries is converted to the new "imply"
statement. This way the PTP subsystem may have Kconfig dependencies of
its own, such as POSIX_TIMERS, without having to make those ethernet
drivers unavailable if POSIX timers are cconfigured out. And when support
for POSIX timers is selected again then the default config option for PTP
clock support will automatically be adjusted accordingly.

The pch_gbe driver is a bit special as it relies on extra code in
drivers/ptp/ptp_pch.c. Therefore we let the make process descend into
drivers/ptp/ even if PTP_1588_CLOCK is unselected.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: linux-kbuild@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: Michal Marek <mmarek@suse.com>
Link: http://lkml.kernel.org/r/1478841010-28605-4-git-send-email-nicolas.pitre@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 09:26:34 +01:00
Madalin Bucur
ff86aae3b4 devres: add devm_alloc_percpu()
Introduce managed counterparts for alloc_percpu() and free_percpu().
Add devm_alloc_percpu() and devm_free_percpu() into the managed
interfaces list.

Signed-off-by: Madalin Bucur <madalin.bucur@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 22:34:25 -05:00
Joel Fernandes
d032ae8921 ftrace: Provide API to use global filtering for ftrace ops
Currently the global_ops filtering hash is not available to outside users
registering for function tracing. Provide an API for those users to be
able to choose global filtering.

This is in preparation for pstore's ftrace feature to be able to
use the global filters.

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Joel Fernandes <joelaf@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:30 -08:00
Joel Fernandes
fbccdeb8d7 pstore: Add ftrace timestamp counter
In preparation for merging the per CPU buffers into one buffer when
we retrieve the pstore ftrace data, we store the timestamp as a
counter in the ftrace pstore record.  We store the CPU number as well
if !PSTORE_CPU_IN_IP, in this case we shift the counter and may lose
ordering there but we preserve the same record size. The timestamp counter
is also racy, and not doing any locking or synchronization here results
in the benefit of lower overhead. Since we don't care much here for exact
ordering of function traces across CPUs, we don't synchronize and may lose
some counter updates but I'm ok with that.

Using trace_clock() results in much lower performance so avoid using it
since we don't want accuracy in timestamp and need a rough ordering to
perform merge.

Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: updated commit message, added comments]
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:27 -08:00
Joel Fernandes
a1cf53ac6d ramoops: Split ftrace buffer space into per-CPU zones
If the RAMOOPS_FLAG_FTRACE_PER_CPU flag is passed to ramoops pdata, split
the ftrace space into multiple zones depending on the number of CPUs.

This speeds up the performance of function tracing by about 280% in my
tests as we avoid the locking. The trade off being lesser space available
per CPU. Let the ramoops user decide which option they want based on pdata
flag.

Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: added max_ftrace_cnt to track size, added DT logic and docs]
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:26 -08:00