TPS6507x are multi function (PM, touchscreen) chipsets from TI.
This commit also changes the corresponding regulator driver from being
standalone to an MFD subdevice.
Signed-off-by: Todd Fischer <todd.fischer@ridgerun.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Add mfd structure which refrences sub-driver initialization data. For example,
for a giving hardware implementation, the voltage regulator sub-driver
initialization data provides the mapping betten a voltage regulator and what
the output voltage is being used for.
Signed-off-by: Todd Fischer <todd.fischer@ridgerun.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Fri, 2 Apr 2010 15:31:03 +0000 (16:31 +0100)]
mfd: Improve WM831x AUXADC completion handling
Currently completion of WM831x AUXADC conversions is monitored by
checking for convertor enable. Due to the mechanism used to ensure
data corruption is avoided when reading AUXADC data there may under
heavy I/O be a window where this bit has cleared but the conversion
results have not been updated. Data availability is only guaranteed
after the AUXADC data interrupt has been asserted.
Avoid this by always using the interrupt to detect completion. If the
chip IRQ is not set up then we poll the IRQ status register for up to
5ms. If it is set up then we rely on the data done interrupt with a
vastly increased timeout, failing the conversion if the interrupt is
not generated.
This also saves a register read when using interrupts.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Ira W. Snyder [Wed, 7 Apr 2010 08:08:01 +0000 (10:08 +0200)]
gpio: Add support for Janz VMOD-TTL Digital IO module
The Janz VMOD-TTL is a MODULbus daughterboard which fits onto any MODULbus
carrier board. It essentially consists of some various logic and a Zilog
Z8536 CIO Counter/Timer and Parallel IO Unit.
The board must be physically configured with jumpers to enable a user to
drive output signals. I am only interested in outputs, so I have made this
driver as simple as possible. It only supports a very minimal subset of the
features provided by the Z8536 chip.
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Ira W. Snyder [Mon, 29 Mar 2010 16:58:51 +0000 (09:58 -0700)]
can: Add support for Janz VMOD-ICAN3 Intelligent CAN module
The Janz VMOD-ICAN3 is a MODULbus daughterboard which fits onto any
MODULbus carrier board. It is an intelligent CAN controller with a
microcontroller and associated firmware.
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu> Acked-by: Wolfgang Grandegger <wg@grandegger.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Ira W. Snyder [Wed, 7 Apr 2010 07:43:00 +0000 (09:43 +0200)]
mfd: Janz CMOD-IO PCI MODULbus Carrier Board support
The Janz CMOD-IO PCI MODULbus carrier board is a PCI to MODULbus bridge,
which may host many different types of MODULbus daughterboards, including
CAN and GPIO controllers.
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu> Reviewed-by: Wolfgang Grandegger <wg@grandegger.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
WARNING: drivers/mfd/88pm860x.o(.text+0x12): Section mismatch in
reference from the function pm860x_device_exit() to the function
.devexit.text:device_irq_exit()
The function pm860x_device_exit() references a function in an exit
section.
Often the function device_irq_exit() has valid usage outside the exit
section
and the fix is to remove the __devexit annotation of device_irq_exit.
WARNING: drivers/mfd/88pm860x.o(.text+0xb0): Section mismatch in
reference from the function pm860x_device_init() to the function
.devinit.text:device_8606_init()
The function pm860x_device_init() references
the function __devinit device_8606_init().
This is often because pm860x_device_init lacks a __devinit
annotation or the annotation of device_8606_init is wrong.
WARNING: drivers/mfd/88pm860x.o(.text+0xbe): Section mismatch in
reference from the function pm860x_device_init() to the function
.devinit.text:device_8607_init()
The function pm860x_device_init() references
the function __devinit device_8607_init().
This is often because pm860x_device_init lacks a __devinit
annotation or the annotation of device_8607_init is wrong.
Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Dan Carpenter [Mon, 22 Mar 2010 12:12:42 +0000 (15:12 +0300)]
mfd: Off by one calculating size for timberdale
I'm pretty sure that it should be + 1 here. It's an off by one, because
we start counting at zero.
Signed-off-by: Dan Carpenter <error27@gmail.com> Acked-by: Richard Röjfors <richard.rojfors@pelagicore.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Florian Fainelli [Tue, 23 Mar 2010 02:56:24 +0000 (22:56 -0400)]
watchdog: Convert rdc321x_wdt to use southbridge pci device
The RDC321x MFD southbridge driver will pass a reference to the
southbridge PCI device which should be used by the watchdog driver for its
operations. This patch converts the watchdog driver to use the pci_dev
pointer and make use of the base register resource which is passed along
with the platform device.
Signed-off-by: Florian Fainelli <florian@openwrt.org> Acked-by: Wim Van Sebroeck <wim@iguana.be> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Florian Fainelli [Sun, 21 Mar 2010 00:06:05 +0000 (01:06 +0100)]
mfd: Add support for the RDC321x southbridge
This patch adds a new MFD driver for the RDC321x southbridge. This southbridge
is always present in the RDC321x System-on-a-Chip and provides access to some
GPIOs as well as a watchdog. Access to these two functions is done using the
southbridge PCI device configuration space.
Signed-off-by: Florian Fainelli <florian@openwrt.org> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Wolfram Sang [Sat, 20 Mar 2010 14:12:54 +0000 (15:12 +0100)]
mfd: Fix dangling pointers
Fix I2C-drivers which missed setting clientdata to NULL before freeing the
structure it points to. Also fix drivers which do this _after_ the structure
was freed already.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Linus Torvalds [Thu, 27 May 2010 22:23:47 +0000 (15:23 -0700)]
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (61 commits)
tracing: Add __used annotation to event variable
perf, trace: Fix !x86 build bug
perf report: Support multiple events on the TUI
perf annotate: Fix up usage of the build id cache
x86/mmiotrace: Remove redundant instruction prefix checks
perf annotate: Add TUI interface
perf tui: Remove annotate from popup menu after failure
perf report: Don't start the TUI if -D is used
perf: Fix getline undeclared
perf: Optimize perf_tp_event_match()
perf: Remove more code from the fastpath
perf: Optimize the !vmalloc backed buffer
perf: Optimize perf_output_copy()
perf: Fix wakeup storm for RO mmap()s
perf-record: Share per-cpu buffers
perf-record: Remove -M
perf: Ensure that IOC_OUTPUT isn't used to create multi-writer buffers
perf, trace: Optimize tracepoints by using per-tracepoint-per-cpu hlist to track events
perf, trace: Optimize tracepoints by removing IRQ-disable from perf/tracepoint interaction
perf tui: Allow disabling the TUI on a per command basis in ~/.perfconfig
...
Linus Torvalds [Thu, 27 May 2010 18:34:20 +0000 (11:34 -0700)]
Merge branch 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds
* 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds:
leds: Add mx31moboard MC13783 led support
leds: Add mc13783 LED support
leds: leds-ss4200: fix led_classdev_unregister twice in error handling
leds: leds-lp3944: properly handle lp3944_configure fail in lp3944_probe
leds: led-class: set permissions on max_brightness file to 0444
leds: leds-gpio: Change blink_set callback to be able to turn off blinking
leds: Add LED driver for the Soekris net5501 board
leds: 88pm860x - fix checking in probe function
Linus Torvalds [Thu, 27 May 2010 18:33:46 +0000 (11:33 -0700)]
Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging: (23 commits)
hwmon: (lm75) Add support for the Texas Instruments TMP105
hwmon: (ltc4245) Read only one GPIO pin
hwmon: (dme1737) Add SCH5127 support
hwmon: (tmp102) Don't always stop chip at exit
hwmon: (tmp102) Fix suspend and resume functions
hwmon: (tmp102) Various fixes
hwmon: Driver for TI TMP102 temperature sensor
hwmon: EMC1403 thermal sensor support
hwmon: (applesmc) Add temperature sensor labels to sysfs interface
hwmon: (applesmc) Add generic support for MacBook Pro 7
hwmon: (applesmc) Add generic support for MacBook Pro 6
hwmon: (applesmc) Add support for MacBook Pro 5,3 and 5,4
hwmon: (tmp401) Reorganize code to get rid of static forward declarations
hwmon: (tmp401) Use constants for sysfs file permissions
hwmon: (adm1031) Allow setting update rate
hwmon: Add description of the update_rate sysfs attribute
hwmon: (lm90) Use programmed update rate
hwmon: (f71882fg) Acquire I/O regions while we're working with them
hwmon: (f71882fg) Code cleanup
hwmon: (f71882fg) Use strict_stro(l|ul) instead of simple_strto$1
...
Ira W. Snyder [Thu, 27 May 2010 17:59:02 +0000 (19:59 +0200)]
hwmon: (ltc4245) Read only one GPIO pin
Read only one of the GPIO pins as an analog voltage. The ADC can be
switched to a different GPIO pin at runtime, but this is not supported.
Previously, this driver would report the analog voltage of the currently
selected GPIO pin as all three GPIO voltages: in9_input, in10_input and
in11_input.
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu> Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: stable@kernel.org
Jean Delvare [Thu, 27 May 2010 17:58:57 +0000 (19:58 +0200)]
hwmon: (tmp102) Various fixes
Fixes from my driver review:
http://lists.lm-sensors.org/pipermail/lm-sensors/2010-March/028051.html
Only the small changes are in there, more important changes will come
later separately as time permits.
* Drop the remnants of the now gone detect function
* The TMP102 has no known compatible chip
* Include the right header files
* Clarify why byte swapping of register values is needed
* Strip resolution info bit from temperature register value
* Set cache lifetime to 1/3 second
* Don't arbitrarily reject limit values; clamp as needed
* Make limit writing unconditional
* Don't check for transaction types the driver doesn't use
* Properly check for error when setting configuration
* Report error on failed probe
* Make the driver load automatically where needed
* Various other minor fixes
Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Steven King <sfking@fdwdc.com>
Steven King [Thu, 27 May 2010 17:58:56 +0000 (19:58 +0200)]
hwmon: Driver for TI TMP102 temperature sensor
Driver for the TI TMP102.
The TI TMP102 is similar to the LM75. It differs from the LM75 by
having a 16-bit conf register and the temp registers have a minimum
resolution of 12 bits; the extended conf register can select 13-bit
resolution (which this driver does) and also change the update rate
(which this driver currently doesn't use).
[JD: Fix tmp102_exit tag, must be __exit, not __init.]
Signed-off-by: Steven King <sfking@fdwdc.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Kalhan Trisal [Thu, 27 May 2010 17:58:56 +0000 (19:58 +0200)]
hwmon: EMC1403 thermal sensor support
Provides support for the EMC1403 thermal sensor. Only reporting of values
is supported. The various Moorestown specific extras to do with thermal
alerts and the like are not in this version of the driver.
Considerably edited and tidied up by Alan Cox, plus fixes and detection
bits from Jean Delvare.
Signed-off-by: Kalhan Trisal <kalhan.trisal@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Alex Murray [Thu, 27 May 2010 17:58:54 +0000 (19:58 +0200)]
hwmon: (applesmc) Add temperature sensor labels to sysfs interface
The Apple SMC uses a systematic labeling scheme for the hardware
temperature sensors. This scheme is currently hidden from
userland. Since the sensor set, and consequently the numbering,
differs between models, an extensive database of configurations is
required for an application such as fan control. This patch adds the
SMC labels to the hwmon sysfs interface, allowing applications to use
the sensors more intelligibly.
[rydberg@euromail.se: fixed error handling] Signed-off-by: Alex Murray <murray.alex@gmail.com> Signed-off-by: Henrik Rydberg <rydberg@euromail.se> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Bernhard Froemel [Thu, 27 May 2010 17:58:52 +0000 (19:58 +0200)]
hwmon: (applesmc) Add generic support for MacBook Pro 6
This patch adds generic support for the MacBook Pro 6 family
based on the 6,2 model.
[rydberg@euromail.se: patch cleanup] Signed-off-by: Bernhard Froemel <froemel@vmars.tuwien.ac.at> Signed-off-by: Henrik Rydberg <rydberg@euromail.se> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Jean Delvare [Thu, 27 May 2010 17:58:46 +0000 (19:58 +0200)]
hwmon: (adm1031) Allow setting update rate
Based on earlier work by Ira W. Snyder.
The adm1031 chip is capable of using a runtime configurable sampling rate,
using the fan filter register. Add support for reading and setting the
update rate via sysfs.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Ira W. Snyder <iws@ovro.caltech.edu>
Ira W. Snyder [Thu, 27 May 2010 17:58:44 +0000 (19:58 +0200)]
hwmon: (lm90) Use programmed update rate
The lm90 driver programs the sensor chip to update its readings at 2 Hz
(500 ms between readings). However, the driver only does reads from the
chip at intervals of 2 * HZ (2000 ms between readings). Change the driver
update rate to the programmed update rate.
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Matthew Garrett [Thu, 27 May 2010 17:58:38 +0000 (19:58 +0200)]
hwmon: (lm63) Add basic support for LM64
The LM64 appears to be an LM63 with added GPIO lines. Add support for the
hwmon functionality - GPIO can be added at some later stage if someone
has a need for them.
Signed-off-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Jean Delvare [Thu, 27 May 2010 17:58:37 +0000 (19:58 +0200)]
hwmon: (asus_atk0110) Don't load if ACPI resources aren't enforced
When the user passes the kernel parameter acpi_enforce_resources=lax,
the ACPI resources are no longer protected, so a native driver can
make use of them. In that case, we do not want the asus_atk0110 to be
loaded. Unfortunately, this driver loads automatically due to its
MODULE_DEVICE_TABLE, so the user ends up with two drivers loaded for
the same device - this is bad.
So I suggest that we prevent the asus_atk0110 driver from loading if
acpi_enforce_resources=lax.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Luca Tettamanti <kronos.it@gmail.com> Cc: Len Brown <lenb@kernel.org>
Linus Torvalds [Thu, 27 May 2010 17:47:41 +0000 (10:47 -0700)]
Merge branch 'sfi-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-sfi-2.6
* 'sfi-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-sfi-2.6:
SFI: add sysfs interface for SFI tables.
SFI: add support for v0.81 spec
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (27 commits)
Btrfs: add more error checking to btrfs_dirty_inode
Btrfs: allow unaligned DIO
Btrfs: drop verbose enospc printk
Btrfs: Fix block generation verification race
Btrfs: fix preallocation and nodatacow checks in O_DIRECT
Btrfs: avoid ENOSPC errors in btrfs_dirty_inode
Btrfs: move O_DIRECT space reservation to btrfs_direct_IO
Btrfs: rework O_DIRECT enospc handling
Btrfs: use async helpers for DIO write checksumming
Btrfs: don't walk around with task->state != TASK_RUNNING
Btrfs: do aio_write instead of write
Btrfs: add basic DIO read/write support
direct-io: do not merge logically non-contiguous requests
direct-io: add a hook for the fs to provide its own submit_bio function
fs: allow short direct-io reads to be completed via buffered IO
Btrfs: Metadata ENOSPC handling for balance
Btrfs: Pre-allocate space for data relocation
Btrfs: Metadata ENOSPC handling for tree log
Btrfs: Metadata reservation for orphan inodes
Btrfs: Introduce global metadata reservation
...
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6:
[SCSI] fix race in scsi_target_reap
[SCSI] aacraid: Eliminate use after free
[SCSI] arcmsr: Support HW reset for EH and polling scheme for scsi device
[SCSI] bfa: fix system crash when reading sysfs fc_host statistics
[SCSI] iscsi_tcp: remove sk_sleep check
[SCSI] ipr: improve interrupt service routine performance
[SCSI] ipr: set the data list length in the request control block
[SCSI] ipr: fix a register read to use the correct address for 64 bit adapters
[SCSI] ipr: include the resource path in the IOA status area structure
[SCSI] ipr: implement fixes for 64 bit adapter support
[SCSI] be2iscsi: correct return value in mgmt_invalidate_icds()
Linus Torvalds [Thu, 27 May 2010 17:26:37 +0000 (10:26 -0700)]
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (40 commits)
ext4: Make fsync sync new parent directories in no-journal mode
ext4: Drop whitespace at end of lines
ext4: Fix compat EXT4_IOC_ADD_GROUP
ext4: Conditionally define compat ioctl numbers
tracing: Convert more ext4 events to DEFINE_EVENT
ext4: Add new tracepoints to track mballoc's buddy bitmap loads
ext4: Add a missing trace hook
ext4: restart ext4_ext_remove_space() after transaction restart
ext4: Clear the EXT4_EOFBLOCKS_FL flag only when warranted
ext4: Avoid crashing on NULL ptr dereference on a filesystem error
ext4: Use bitops to read/modify i_flags in struct ext4_inode_info
ext4: Convert calls of ext4_error() to EXT4_ERROR_INODE()
ext4: Convert callers of ext4_get_blocks() to use ext4_map_blocks()
ext4: Add new abstraction ext4_map_blocks() underneath ext4_get_blocks()
ext4: Use our own write_cache_pages()
ext4: Show journal_checksum option
ext4: Fix for ext4_mb_collect_stats()
ext4: check for a good block group before loading buddy pages
ext4: Prevent creation of files larger than RLIMIT_FSIZE using fallocate
ext4: Remove extraneous newlines in ext4_msg() calls
...
Linus Torvalds [Thu, 27 May 2010 17:22:06 +0000 (10:22 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
ieee1394: schedule for removal
firewire: core: use separate timeout for each transaction
firewire: core: Fix tlabel exhaustion problem
firewire: core: make transaction label allocation more robust
firewire: core: clean up config ROM related defined constants
ieee1394: mark char device files as not seekable
firewire: cdev: mark char device files as not seekable
firewire: ohci: cleanups and fix for nonstandard build without debug facility
firewire: ohci: wait for PHY register accesses to complete
firewire: ohci: fix up configuration of TI chips
firewire: ohci: enable 1394a enhancements
firewire: ohci: do not clear PHY interrupt status inadvertently
firewire: ohci: add a function for reading PHY registers
Trivial conflicts in Documentation/feature-removal-schedule.txt
Linus Torvalds [Thu, 27 May 2010 17:18:44 +0000 (10:18 -0700)]
Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
NFS: Fix another nfs_wb_page() deadlock
NFS: Ensure that we mark the inode as dirty if we exit early from commit
NFS: Fix a lock imbalance typo in nfs_access_cache_shrinker
sunrpc: fix leak on error on socket xprt setup
Linus Torvalds [Thu, 27 May 2010 16:19:55 +0000 (09:19 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: usbtouchscreen - support bigger iNexio touchscreens
Input: ads7846 - return error on regulator_get() failure
Input: twl4030-vibra - correct the power down sequence
Input: enable onkey driver of max8925
Input: use ABS_CNT rather than (ABS_MAX + 1)
Lee Schermerhorn [Wed, 26 May 2010 21:45:06 +0000 (14:45 -0700)]
numa: update Documentation/vm/numa, add memoryless node info
Kamezawa Hiroyuki requested documentation for the numa_mem_id() and slab
related changes. He suggested Documentation/vm/numa for this
documentation. Looking at this file, it seems to me to be hopelessly out
of date relative to current Linux NUMA support. At the risk of going down
a rathole, I have made an attempt to rewrite the doc at a slightly higher
level [I think] and provide pointers to other in-tree documents and
out-of-tree man pages that cover the details.
Let the games begin.
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Tejun Heo <tj@kernel.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Eric Whitney <eric.whitney@hp.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lee Schermerhorn [Wed, 26 May 2010 21:45:04 +0000 (14:45 -0700)]
numa: in-kernel profiling: use cpu_to_mem() for per cpu allocations
In kernel profiling requires that we be able to allocate "local" memory
for each cpu. Use "cpu_to_mem()" instead of "cpu_to_node()" to support
memoryless nodes.
Depends on the "numa_mem_id()" patch.
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Tejun Heo <tj@kernel.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Eric Whitney <eric.whitney@hp.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lee Schermerhorn [Wed, 26 May 2010 21:45:03 +0000 (14:45 -0700)]
numa: slab: use numa_mem_id() for slab local memory node
Example usage of generic "numa_mem_id()":
The mainline slab code, since ~ 2.6.19, does not handle memoryless nodes
well. Specifically, the "fast path"--____cache_alloc()--will never
succeed as slab doesn't cache offnode object on the per cpu queues, and
for memoryless nodes, all memory will be "off node" relative to
numa_node_id(). This adds significant overhead to all kmem cache
allocations, incurring a significant regression relative to earlier
kernels [from before slab.c was reorganized].
This patch uses the generic topology function "numa_mem_id()" to return
the "effective local memory node" for the calling context. This is the
first node in the local node's generic fallback zonelist-- the same node
that "local" mempolicy-based allocations would use. This lets slab cache
these "local" allocations and avoid fallback/refill on every allocation.
N.B.: Slab will need to handle node and memory hotplug events that could
change the value returned by numa_mem_id() for any given node if recent
changes to address memory hotplug don't already address this. E.g., flush
all per cpu slab queues before rebuilding the zonelists while the
"machine" is held in the stopped state.
Performance impact on "hackbench 400 process 200"
2.6.34-rc3-mmotm-100405-1609 no-patch this-patch
ia64 no memoryless nodes [avg of 10]: 11.713 11.637 ~0.65 diff
ia64 cpus all on memless nodes [10]: 228.259 26.484 ~8.6x speedup
The slowdown of the patched kernel from ~12 sec to ~28 seconds when
configured with memoryless nodes is the result of all cpus allocating from
a single node's mm pagepool. The cache lines of the single node are
distributed/interleaved over the memory of the real physical nodes, but
the zone lock, list heads, ... of the single node with memory still each
live in a single cache line that is accessed from all processors.
x86_64 [8x6 AMD] [avg of 40]: 2.883 2.845
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Tejun Heo <tj@kernel.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Eric Whitney <eric.whitney@hp.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lee Schermerhorn [Wed, 26 May 2010 21:45:01 +0000 (14:45 -0700)]
numa: ia64: support numa_mem_id() for memoryless nodes
Enable 'HAVE_MEMORYLESS_NODES' by default when NUMA configured on ia64.
Initialize percpu 'numa_mem' variable when starting secondary cpus.
Generic initialization will handle the boot cpu.
Nothing uses 'numa_mem_id()' yet. Subsequent patch with modify slab to
use this.
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Tejun Heo <tj@kernel.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Eric Whitney <eric.whitney@hp.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lee Schermerhorn [Wed, 26 May 2010 21:45:00 +0000 (14:45 -0700)]
numa: introduce numa_mem_id()- effective local memory node id
Introduce numa_mem_id(), based on generic percpu variable infrastructure
to track "nearest node with memory" for archs that support memoryless
nodes.
Define API in <linux/topology.h> when CONFIG_HAVE_MEMORYLESS_NODES
defined, else stubs. Architectures will define HAVE_MEMORYLESS_NODES
if/when they support them.
Archs can override definitions of:
numa_mem_id() - returns node number of "local memory" node
set_numa_mem() - initialize [this cpus'] per cpu variable 'numa_mem'
cpu_to_mem() - return numa_mem for specified cpu; may be used as lvalue
Generic initialization of 'numa_mem' occurs in __build_all_zonelists().
This will initialize the boot cpu at boot time, and all cpus on change of
numa_zonelist_order, or when node or memory hot-plug requires zonelist
rebuild. Archs that support memoryless nodes will need to initialize
'numa_mem' for secondary cpus as they're brought on-line.
[akpm@linux-foundation.org: fix build] Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Cc: Tejun Heo <tj@kernel.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Eric Whitney <eric.whitney@hp.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lee Schermerhorn [Wed, 26 May 2010 21:44:59 +0000 (14:44 -0700)]
numa: ia64: use generic percpu var numa_node_id() implementation
ia64: Use generic percpu implementation of numa_node_id()
+ intialize per cpu 'numa_node'
+ remove ia64 cpu_to_node() macro; use generic
+ define CONFIG_USE_PERCPU_NUMA_NODE_ID when NUMA configured
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Tejun Heo <tj@kernel.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Eric Whitney <eric.whitney@hp.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lee Schermerhorn [Wed, 26 May 2010 21:44:58 +0000 (14:44 -0700)]
numa: x86_64: use generic percpu var numa_node_id() implementation
x86 arch specific changes to use generic numa_node_id() based on generic
percpu variable infrastructure. Back out x86's custom version of
numa_node_id()
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Tejun Heo <tj@kernel.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Eric Whitney <eric.whitney@hp.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lee Schermerhorn [Wed, 26 May 2010 21:44:56 +0000 (14:44 -0700)]
numa: add generic percpu var numa_node_id() implementation
Rework the generic version of the numa_node_id() function to use the new
generic percpu variable infrastructure.
Guard the new implementation with a new config option:
CONFIG_USE_PERCPU_NUMA_NODE_ID.
Archs which support this new implemention will default this option to 'y'
when NUMA is configured. This config option could be removed if/when all
archs switch over to the generic percpu implementation of numa_node_id().
Arch support involves:
1) converting any existing per cpu variable implementations to use
this implementation. x86_64 is an instance of such an arch.
2) archs that don't use a per cpu variable for numa_node_id() will
need to initialize the new per cpu variable "numa_node" as cpus
are brought on-line. ia64 is an example.
3) Defining USE_PERCPU_NUMA_NODE_ID in arch dependent Kconfig--e.g.,
when NUMA is configured. This is required because I have
retained the old implementation by default to allow archs to
be modified incrementally, as desired.
Subsequent patches will convert x86_64 and ia64 to use this implemenation.
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Tejun Heo <tj@kernel.org> Cc: Mel Gorman <mel@csn.ul.ie> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Eric Whitney <eric.whitney@hp.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Blunck [Wed, 26 May 2010 21:44:54 +0000 (14:44 -0700)]
Documentation/filesystems/Locking: update documentation on llseek() wrt BKL
The inode's i_size is not protected by the big kernel lock. Therefore it
does not make sense to recommend taking the BKL in filesystems llseek
operations. Instead it should use the inode's mutex or use just use
i_size_read() instead. Add a note that this is not protecting
file->f_pos.
Signed-off-by: Jan Blunck <jblunck@suse.de> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: John Kacur <jkacur@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
jan Blunck [Wed, 26 May 2010 21:44:53 +0000 (14:44 -0700)]
fs/: do not fallback to default_llseek() when readdir() uses BKL
Do not use the fallback default_llseek() if the readdir operation of the
filesystem still uses the big kernel lock.
Since llseek() modifies
file->f_pos of the directory directly it may need locking to not confuse
readdir which usually uses file->f_pos directly as well
Since the special characteristics of the BKL (unlocked on schedule) are
not necessary in this case, the inode mutex can be used for locking as
provided by generic_file_llseek(). This is only possible since all
filesystems, except reiserfs, either use a directory as a flat file or
with disk address offsets. Reiserfs on the other hand uses a 32bit hash
off the filename as the offset so generic_file_llseek() can get used as
well since the hash is always smaller than sb->s_maxbytes (= (512 << 32) -
blocksize).
Signed-off-by: Jan Blunck <jblunck@suse.de> Acked-by: Jan Kara <jack@suse.cz> Acked-by: Anders Larsen <al@alarsen.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Blunck [Wed, 26 May 2010 21:44:51 +0000 (14:44 -0700)]
st: use noop_llseek() instead of default_llseek()
st_open() suggests that llseek() doesn't work: "We really want to do
nonseekable_open(inode, filp); here, but some versions of tar incorrectly
call lseek on tapes and bail out if that fails. So we disallow pread()
and pwrite(), but permit lseeks."
Instead of using the fallback default_llseek() the driver should use
noop_llseek() which leaves the file->f_pos untouched but succeeds.
Signed-off-by: Jan Blunck <jblunck@suse.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Kai Makisara <Kai.Makisara@kolumbus.fi> Cc: Willem Riede <osst@riede.org> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Blunck [Wed, 26 May 2010 21:44:50 +0000 (14:44 -0700)]
osst: use noop_llseek() instead of default_llseek()
__os_scsi_tape_open() suggests that llseek() doesn't work: "We really want
to do nonseekable_open(inode, filp); here, but some versions of tar
incorrectly call lseek on tapes and bail out if that fails. So we
disallow pread() and pwrite(), but permit lseeks."
Instead of using the fallback default_llseek() the driver should use
noop_llseek() which leaves the file->f_pos untouched but succeeds.
Signed-off-by: Jan Blunck <jblunck@suse.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Willem Riede <osst@riede.org> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
jan Blunck [Wed, 26 May 2010 21:44:48 +0000 (14:44 -0700)]
vfs: introduce noop_llseek()
This is an implementation of ->llseek useable for the rare special case
when userspace expects the seek to succeed but the (device) file is
actually not able to perform the seek. In this case you use noop_llseek()
instead of falling back to the default implementation of ->llseek.
Signed-off-by: Jan Blunck <jblunck@suse.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Blunck [Wed, 26 May 2010 21:44:46 +0000 (14:44 -0700)]
mISDN: remove unnecessary test on f_pos
This test is not doing anything since it is always false if the
mISDN_read() is called from vfs_read(). Besides that the driver uses
nonseekable_open() and is not using off or file->f_pos anywhere.
Signed-off-by: Jan Blunck <jblunck@suse.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Karsten Keil <isdn@linux-pingi.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Blunck [Wed, 26 May 2010 21:44:44 +0000 (14:44 -0700)]
osst: update ppos instead of using file->f_pos
osst_read()/osst_write() modify file->f_pos directly instead of the ppos
given to them. The VFS later updates the file->f_pos and overwrites it
with the value of ppos.
Signed-off-by: Jan Blunck <jblunck@suse.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Willem Riede <osst@riede.org> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
FUJITA Tomonori [Wed, 26 May 2010 21:44:43 +0000 (14:44 -0700)]
parisc: use asm-generic/scatterlist.h
parisc uses iova and iova_length in scatterlist structure instead of
dma_address and dma_length. However, the accessor are used so we can
convert parisc to use asm-generic/scatterlist.h easily.
FUJITA Tomonori [Wed, 26 May 2010 21:44:34 +0000 (14:44 -0700)]
asm-generic: remove ARCH_HAS_SG_CHAIN in scatterlist.h
There are more architectures that don't support ARCH_HAS_SG_CHAIN than
those that support it. This removes removes ARCH_HAS_SG_CHAIN in
asm-generic/scatterlist.h and lets arhictectures to define it.
It's clearer than defining ARCH_HAS_SG_CHAIN asm-generic/scatterlist.h and
undefing it in arhictectures that don't support it.
FUJITA Tomonori [Wed, 26 May 2010 21:44:32 +0000 (14:44 -0700)]
asm-generic: add NEED_SG_DMA_LENGTH to define sg_dma_len()
There are only two ways to define sg_dma_len(); use sg->dma_length or
sg->length. This patch introduces NEED_SG_DMA_LENGTH that enables
architectures to choose sg->dma_length or sg->length.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
FUJITA Tomonori [Wed, 26 May 2010 21:44:30 +0000 (14:44 -0700)]
asm-generic: remove ISA_DMA_THRESHOLD in scatterlist.h
This is the first half of the attempt to use asm-generic/scatterlist.h
on every architecture.
There are only two ways to define scatterlist structure. So it's easy
to convert every architecture to use asm-generic/scatterlist.h.
This patch:
The trick for ISA_DMA_THRESHOLD in asm-generic/scatterlist.h doesn't work
for powerpc. This lets architectures defin ISA_DMA_THRESHOLD.
Hopefully, we can remove ISA_DMA_THRESHOLD in the future; we can do better
to decide if the bouncing is necessary or not.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
lktdm: add support for hardlockup, softlockup and hung task crashes
This adds three new types of kernel "crashes" in the lkdtm driver to
trigger hardlockups, softlockups and task hung states at will.
The first two are useful to test the new generic lockup detector and check
its further regressions. The latter one is a bonus to check the hung task
detector regressions even though it's not currently in rework.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Simon Kagstrom <simon.kagstrom@netinsight.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Don Zickus <dzickus@redhat.com> Cc: Cyrill Gorcunov <gorcunov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
radix-tree: fix radix_tree_prev_hole() underflow case
radix_tree_prev_hole() used LONG_MAX to detect underflow; however,
ULONG_MAX is clearly what was intended, both here and by its only user
(count_history_pages at mm/readahead.c).
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Moyer [Wed, 26 May 2010 21:44:26 +0000 (14:44 -0700)]
aio: fix the compat vectored operations
The aio compat code was not converting the struct iovecs from 32bit to
64bit pointers, causing either EINVAL to be returned from io_getevents, or
EFAULT as the result of the I/O. This patch passes a compat flag to
io_submit to signal that pointer conversion is necessary for a given iocb
array.
A variant of this was tested by Michael Tokarev. I have also updated the
libaio test harness to exercise this code path with good success.
Further, I grabbed a copy of ltp and ran the
testcases/kernel/syscall/readv and writev tests there (compiled with -m32
on my 64bit system). All seems happy, but extra eyes on this would be
welcome.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix CONFIG_COMPAT=n build] Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Reported-by: Michael Tokarev <mjt@tls.msk.ru> Cc: Zach Brown <zach.brown@oracle.com> Cc: <stable@kernel.org> [2.6.35.1] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>