3-axis accelerometer sensor (2/4/8 g) with 12-bit resolution
and I2C interface
many extra features are unsupported (freefall detection, orientation
change, autosleep)
datasheet is here:
http://cache.freescale.com/files/sensors/doc/data_sheet/MMA8452Q.pdf
v2: (thanks to Jonathan Cameron)
* use ARRAY_SIZE()
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Fixing issue caused by clash of two patches, one adding a name with
the acpi enumeration patch.
54ab3e24 Beomho Seo 2014-04-02 @572 indio_dev->name = id->name;
d913971e Srinivas Pandruvada 2014-03-19 574 indio_dev->name = name;
The name added by commit 54ab3e24 is not required as this is already
added by taking care of case where id is NULL.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
has been in use for a long time, but never documented;
state that this measurement should be in lux (drivers may feel
different about this)
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
intensity has been in use for a long time but never documented
it is beneficial to document what this is supposed to be
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
useful for contactless temperature sensors to distinguish
between the ambient temperature and the temperature of the object
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
I2C-controlled sensor with 10-bit pressure and temperature measurement
datasheet: http://cache.freescale.com/files/sensors/doc/data_sheet/MPL3115A2.pdf
v2:
* use devm_iio_device_register()
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
DR bits need to be shifted; since MAG3110_CTRL_DR_DEFAULT is
zero, the change has no effect
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
My static checker is upset that we check IS_ERR(t->reg) when we know it
is not an ERR_PTR.
Checking for IS_ERR() twice is often a sign of confusion and buggy code.
In this case, if the call to "ret = regulator_enable(st->vref);" fails,
then we call "regulator_disable(st->vref);" and that's a mistake because
"st->vref" is not enabled.
I fixed these problems and Hartmut Knaack pointed out a couple unneeded
IS_ERR() checks in ad799x_remove() so I have removed those as well.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Hartmut Knaack <knaack.h@gmx.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Add reinit_completion() before the wait_for_completion_timeout in
raw_read() call.
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Do a soft reset software if a timeout happens.
This is applicable only for ADC_V2.
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
ADC module on Exynos5 SoCs runs at 600KSPS. At this conversion rate,
waiting for 1000 msecs is wasteful (incase of h/w failure).
Hence, reduce the time out to 100msecs and use
wait_for_completion_timeout() instead of
wait_for_completion_interruptible_timeout()
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This patch maintains the following order in
probe(), remove(), resume() and suspend() calls
regulator enable, clk prepare enable
...
clk disable unprepare, regulator disable
While at it,
1. enable the regulator before the iio_device_register()
2. handle the return values for enable/disable calls
Signed-off-by: Naveen Krishna Ch <ch.naveen@samsung.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Added documentation for reading quaternion components for 3D rotations.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Added usage id processing for device rotation. This uses IIO
interfaces for triggered buffer to present data to user
mode.This uses HID sensor framework for registering callback
events from the sensor hub.
Data is exported to user space in the form of quaternion rotation
format.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Added quaternion in the list of supported modifiers.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
The current scan element type uses the following format:
[be|le]:[s|u]bits/storagebits[>>shift].
To specify multiple elements in this type, added a repeat value.
So new format is:
[be|le]:[s|u]bits/storagebitsXr[>>shift].
Here r is specifying how may times, real/storage bits are repeating.
When X is value is 0 or 1, then repeat value is not used in the format,
and it will be same as existing format.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This callback is introduced to overcome some limitations of existing
read_raw callback. The functionality of both existing read_raw and
read_raw_multi is similar, both are used to request values from the
device. The current read_raw callback allows only two return values.
The new read_raw_multi allows returning multiple values. Instead of
passing just address of val and val2, it passes length and pointer
to values. Depending on the type and length of passed buffer, iio
client drivers can return multiple values.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Introduce devm_kmemdup, which uses resource managed kmalloc.
There are several request from maintainers to add this instead
of using kmemdup.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
The asm-generic, big-endian version of zero_bytemask creates a mask of
bytes preceding the first zero-byte by left shifting ~0ul based on the
position of the first zero byte.
Unfortunately, if the first (top) byte is zero, the output of
prep_zero_mask has only the top bit set, resulting in undefined C
behaviour as we shift left by an amount equal to the width of the type.
As it happens, GCC doesn't manage to spot this through the call to fls(),
but the issue remains if architectures choose to implement their shift
instructions differently.
An example would be arch/arm/ (AArch32), where LSL Rd, Rn, #32 results
in Rd == 0x0, whilst on arch/arm64 (AArch64) LSL Xd, Xn, #64 results in
Xd == Xn.
Rather than check explicitly for the problematic shift, this patch adds
an extra shift by 1, replacing fls with __fls. Since zero_bytemask is
never called with a zero argument (has_zero() is used to check the data
first), we don't need to worry about calling __fls(0), which is
undefined.
Cc: <stable@vger.kernel.org>
Cc: Victor Kamensky <victor.kamensky@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This merges the patch to fix possible loss of dirty bit on munmap() or
madvice(DONTNEED). If there are concurrent writers on other CPU's that
have the unmapped/unneeded page in their TLBs, their writes to the page
could possibly get lost if a third CPU raced with the TLB flush and did
a page_mkclean() before the page was fully written.
Admittedly, if you unmap() or madvice(DONTNEED) an area _while_ another
thread is still busy writing to it, you deserve all the lost writes you
could get. But we kernel people hold ourselves to higher quality
standards than "crazy people deserve to lose", because, well, we've seen
people do all kinds of crazy things.
So let's get it right, just because we can, and we don't have to worry
about it.
* safe-dirty-tlb-flush:
mm: split 'tlb_flush_mmu()' into tlb flushing and memory freeing parts
Pull btrfs fixes from Chris Mason.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: limit the path size in send to PATH_MAX
Btrfs: correctly set profile flags on seqlock retry
Btrfs: use correct key when repeating search for extent item
Btrfs: fix inode caching vs tree log
Btrfs: fix possible memory leaks in open_ctree()
Btrfs: avoid triggering bug_on() when we fail to start inode caching task
Btrfs: move btrfs_{set,clear}_and_info() to ctree.h
btrfs: replace error code from btrfs_drop_extents
btrfs: Change the hole range to a more accurate value.
btrfs: fix use-after-free in mount_subvol()
Pull arm fixes from Russell King:
"A number of fixes for the PJ4/iwmmxt changes which arm-soc forced me
to take during the merge window. This stuff should have been better
tested and sorted out *before* the merge window"
* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
ARM: 8042/1: iwmmxt: allow to build iWMMXt on Marvell PJ4B
ARM: 8041/1: pj4: fix cpu_is_pj4 check
ARM: 8040/1: pj4: properly detect existence of iWMMXt coprocessor
ARM: 8039/1: pj4: enable iWMMXt only if CONFIG_IWMMXT is set
ARM: 8038/1: iwmmxt: explicitly check for supported architectures
Quiet the warning below in Lustre code.
Actually the warning is invalid since we either always assign
the symname in ll_readlink_internal or return an error there and
then the following rc check would assign symlink variable explicitly.
In file included from /home/green/bk/linux/drivers/staging/lustre/lustre/llite/../include/linux/lustre_compat25.h:41:0,
from /home/green/bk/linux/drivers/staging/lustre/lustre/llite/../include/linux/lvfs.h:48,
from /home/green/bk/linux/drivers/staging/lustre/lustre/llite/../include/lvfs.h:45,
from /home/green/bk/linux/drivers/staging/lustre/lustre/llite/../include/obd_support.h:41,
from /home/green/bk/linux/drivers/staging/lustre/lustre/llite/../include/obd_class.h:40,
from /home/green/bk/linux/drivers/staging/lustre/lustre/llite/../include/linux/lustre_lite.h:49,
from /home/green/bk/linux/drivers/staging/lustre/lustre/llite/../include/lustre_lite.h:45,
from /home/green/bk/linux/drivers/staging/lustre/lustre/llite/symlink.c:42:
/home/green/bk/linux/drivers/staging/lustre/lustre/llite/symlink.c: In function ‘ll_follow_link’:
/home/green/bk/linux/include/linux/namei.h:88:29: warning: ‘symname’ may be used uninitialized in this function [-Wmaybe-uninitialized]
nd->saved_names[nd->depth] = path;
^
/home/green/bk/linux/drivers/staging/lustre/lustre/llite/symlink.c:123:8: note: ‘symname’ was declared here
char *symname;
^
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull irq fixes from Thomas Gleixner:
"A slighlty large fix for a subtle issue in the CPU hotplug code of
certain ARM SoCs, where the not yet online cpu needs to setup the cpu
local timer and needs to set the interrupt affinity to itself.
Setting interrupt affinity to a not online cpu is prohibited and
therefor the timer interrupt ends up on the wrong cpu, which leads to
nasty complications.
The SoC folks tried to hack around that in the SoC code in some more
than nasty ways. The proper solution is to have a way to enforce the
affinity setting to a not online cpu. The core patch to the genirq
code provides that facility and the follow up patches make use of it
in the GIC interrupt controller and the exynos timer driver.
The change to the core code has no implications to existing users,
except for the rename of the locked function and therefor the
necessary fixup in mips/cavium. Aside of that, no runtime impact is
possible, as none of the existing interrupt chips implements anything
which depends on the force argument of the irq_set_affinity()
callback"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
clocksource: Exynos_mct: Register clock event after request_irq()
clocksource: Exynos_mct: Use irq_force_affinity() in cpu bringup
irqchip: Gic: Support forced affinity setting
genirq: Allow forcing cpu affinity of interrupts
Here are a few tty/serial fixes for 3.15-rc3 that resolve a number of
reported issues in the 8250 and samsung serial drivers, as well as a
character loss fix for the tty core that was caused by the lock removal
patches a release ago.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are a few tty/serial fixes for 3.15-rc3 that resolve a number of
reported issues in the 8250 and samsung serial drivers, as well as a
character loss fix for the tty core that was caused by the lock
removal patches a release ago"
* tag 'tty-3.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial_core: fix uart PORT_UNKNOWN handling
serial: samsung: Change barrier() to cpu_relax() in console output
serial: samsung: don't check config for every character
serial: samsung: Use the passed in "port", fixing kgdb w/ no console
serial: 8250: Fix thread unsafe __dma_tx_complete function
8250_core: Fix unwanted TX chars write
tty: Fix race condition between __tty_buffer_request_room and flush_to_ldisc
Here are some small staging and IIO driver fixes for 3.15-rc3.
Nothing major at all, just some assorted issues that people have reported.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-3.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging / IIO driver fixes from Greg KH:
"Here are some small staging and IIO driver fixes for 3.15-rc3.
Nothing major at all, just some assorted issues that people have
reported"
* tag 'staging-3.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: comedi: usbdux: bug fix for accessing 'ao_chanlist' in private data
iio: adc: mxs-lradc: fix warning when buidling on avr32
iio: cm36651: Fix i2c client leak and possible NULL pointer dereference
iio: querying buffer scan_mask should return 0/1
staging:iio:ad2s1200 fix a missing break
iio: adc: at91_adc: correct default shtim value
ARM: at91: at91sam9260: change at91_adc name
ARM: at91: at91sam9g45: change at91_adc name
iio: cm32181: Fix read integration time function
iio: adc: at91_adc: Repair broken platform_data support
lov_fiemap() does not take consider its @vallen parameter, which is
the max buffer size the caller can hold for the fiemap extents.
This patch fixes this and limits the max mapped fiemap extent count
to fit in the preallocted buffer.
This patch also fixes a memory out of bound write issue when the
fiemap call is only for detecting the number of existing extent.
Signed-off-by: Bobi Jam <bobijam.xu@intel.com>
Reviewed-on: http://review.whamcloud.com/9834
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4619
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Patrick Farrell <paf@cray.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Linux VFS and Lustre OST_SYNC RPC are both capable of specifying
fsync() on a sub-extent of the file {start, end} instead of the full
file. This allows less than the full amount of data to be flushed,
reducing or possibly eliminating the work needed before the syscall
can return.
However, the handling of sub-extent of the file for fsync was lost
with the move to CLIO on the client and OSD API on the server. They
were ignoring the passed {start, end} and using {0, OBD_OBJECT_EOF}
instead.
Return the ability to pass a sub-extent for fsync() from the client,
to the specific stripes/OSTs that need the sync operation, and pass
it down to the OSD. The ZFS OSD doesn't handle this yet, but there
is room for improvement in a separate patch.
Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-on: http://review.whamcloud.com/8626
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4388
Reviewed-by: Bobi Jam <bobijam@gmail.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In libcfs_debug_vmsg2, cdls_delay is only clamped between the minimum
and the maximum when it is increased by multiplying by the backoff
factor. It is not clamped when it is decreased by dividing by the
backoff factor. This allows it to achieve values less than the
minimum, which allows a console message to be printed that should have
been skipped. This patch moves the clamping outside of the else
statement, ensuring that cdls_delay is always between the min and the
max after the first time through libcfs_debug_vmsg2.
Signed-off-by: Ryan Haasken <haasken@cray.com>
Reviewed-on: http://review.whamcloud.com/9503
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4711
Reviewed-by: Chris Horn <hornc@cray.com>
Reviewed-by: Ann Koehler <amk@cray.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Removed the checks for oi_lockless from osc_io_read_start() and
osc_io_write_start(). This patch also removes the unnecessary call to
cl_object_attr_get() in osc_io_write_start() before calling
cl_object_attr_set()
Signed-off-by: Swapnil Pimpale <spimpale@ddn.com>
Reviewed-on: http://review.whamcloud.com/8797
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3868
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
spin_is_locked() is always false when the platform is
uniprocessor and CONFIG_DEBUG_SPINLOCK is not enabled.
This patch replaces its assertion by assert_spin_locked().
Signed-off-by: Li Xi <lixi@ddn.com>
Signed-off-by: James Simmons <uja.ornl@gmail.com>
Reviewed-on: http://review.whamcloud.com/8144
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4199
Reviewed-by: Alexey Lyashkov <alexey_lyashkov@xyratex.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In some cases, cl_default_mds_easize might be zero, especially for
MDC connected to non-MDT0, then mdc might pack getattr RPC with
zero eadatasize.
If client is trying to access remote striped directory with
zero eadatasize, MDT will not return layout information of the
striped direcotry, which will be mis-regarded as non-striped
directory.
So we should use cl_max_mds_easize if cl_default_mds_easize is zero.
Signed-off-by: wang di <di.wang@intel.com>
Reviewed-on: http://review.whamcloud.com/9862
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4847
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's not atomic to check the last reference and state of cl_lock
in cl_lock_put(). This can cause a problem that an using lock is
freed, if the process is preempted between atomic_dec_and_test()
and (lock->cll_state == CLS_FREEING).
This problem can be solved by holding a refcount by coh_locks. In
this case, it can be sure that if the lock refcount reaches zero,
nobody else can have any chance to use it again.
Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Reviewed-on: http://review.whamcloud.com/9881
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4558
Reviewed-by: Bobi Jam <bobijam@gmail.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change the LL_IOC_LLOOP_INFO ioctl in the lustre lloop
device driver to return an error instead of causing
panics with LASSERT().
Signed-off-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-on: http://review.whamcloud.com/9888
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4863
Reviewed-by: Nathaniel Clark <nathaniel.l.clark@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Messages which are printed by ll_dirty_page_discard_warn() should not
be rate limited. If they are rate limited, some files which may be
corrupted on client eviction will not be reported to the user.
This patch changes the CWARN to a CDEBUG to disable console message
rate limiting for this message. The dirty page discard warnings are
already limited on a per-file basis by the function vvp_vmpage_error
which calls ll_dirty_page_discard_warn only if the ccc_object's
cob_discard_page_warned == 0.
Signed-off-by: Ryan Haasken <haasken@cray.com>
Reviewed-on: http://review.whamcloud.com/9752
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4799
Reviewed-by: Cory Spitz <spitzcor@cray.com>
Reviewed-by: Ann Koehler <amk@cray.com>
Reviewed-by: Chris Horn <hornc@cray.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
According https://www.kernel.org/doc/Documentation/mutex-design.txt:
- the mutex subsystem is slightly faster and has better scalability
for contended workloads. In terms of 'ops per CPU cycle', the
semaphore kernel performed 551 ops/sec per 1% of CPU time used,
while the mutex kernel performed 3825 ops/sec per 1% of CPU time
used - it was 6.9 times more efficient.
- there are no fastpath tradeoffs, the mutex fastpath is just as
tight as the semaphore fastpath. On x86, the locking fastpath is
2 instructions.
- 'struct mutex' semantics are well-defined and are enforced if
CONFIG_DEBUG_MUTEXES is turned on. Semaphores on the other hand
have virtually no debugging code or instrumentation.
One more benefit of mutex is optimistic spinning. It try to spin for
acquisition when there are no pending waiters and the lock owner is
currently running on a (different) CPU. The rationale is that if the
lock owner is running, it is likely to release the lock soon.
This significantly reduce amount of context switches when locked
region is small and we have high contention.
Signed-off-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-on: http://review.whamcloud.com/9095
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4257
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's just optimization. The mutex subsystem is slightly faster
and has better scalability for contended workloads.
Remove the lustre_lock and it's accessor functions l_lock(),
l_unlock(), l_lock_init(), and l_has_lock() since they have
not been used by the code since Lustre 1.6.
Signed-off-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-on: http://review.whamcloud.com/9294
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4588
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are some kernfs fixes for 3.15-rc3 that resolve some reported
problems. Nothing huge, but all needed.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core fixes from Greg KH:
"Here are some kernfs fixes for 3.15-rc3 that resolve some reported
problems. Nothing huge, but all needed"
* tag 'driver-core-3.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
s390/ccwgroup: Fix memory corruption
kernfs: add back missing error check in kernfs_fop_mmap()
kernfs: fix a subdir count leak
