MyungJoo Ham [Tue, 11 Jan 2011 11:20:05 +0000 (12:20 +0100)]
regulator: Support MAX8998/LP3974 DVS-GPIO
The previous driver did not support BUCK1-DVS3, BUCK1-DVS4, and
BUCK2-DVS2 modes. This patch adds such modes and an option to block
setting buck1/2 voltages out of the preset values.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
MyungJoo Ham [Tue, 4 Jan 2011 05:17:39 +0000 (14:17 +0900)]
mfd: Support LP3974 RTC
The first releases of LP3974 have a large delay in RTC registers,
which requires 2 seconds of delay after writing to a rtc register
(recommended by National Semiconductor's engineers)
before reading it.
If "rtc_delay" field of the platform data is true, the rtc driver
assumes that such delays are required. Although we have not seen
LP3974s without requiring such delays, we assume that such LP3974s
will be released soon (or they have done so already) and they are
supported by "lp3974" without setting "rtc_delay" at the platform
data.
This patch adds delays with msleep when writing values to RTC registers
if the platform data has rtc_delay set.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Andres Salomon [Fri, 31 Dec 2010 04:27:33 +0000 (20:27 -0800)]
i2c: Convert SCx200 driver from using raw PCI to platform device
The SCx200 ACB driver supports ISA hardware as well as PCI. The PCI
hardware is CS5535/CS5536 based, and the device that it grabs is handled by
the cs5535-mfd driver. This converts the SCx200 driver to use a
platform_driver rather than the previous PCI hackery.
The driver used to manually track the iface list (via linked list); now it
only does this for ISA devices. PCI ifaces are handled through standard
driver model lists.
It's unclear what happens in case of errors in the old ISA code; rather than
pretending the code actually cares, I've dropped the (implicit) ignorance
of return values and marked it with a comment.
Signed-off-by: Andres Salomon <dilinger@queued.net> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Andres Salomon [Mon, 29 Nov 2010 23:45:06 +0000 (15:45 -0800)]
x86: OLPC: convert olpc-xo1 driver from pci device to platform device
The cs5535-mfd driver now takes care of the PCI BAR handling; this
means the olpc-xo1 driver shouldn't be touching the PCI device at all.
This patch uses both cs5535-acpi and cs5535-pms platform devices rather
than a single platform device because the cs5535-mfd driver may be used
by other CS5535 platform-specific drivers; OLPC doesn't get to dictate
that ACPI and PMS will always be used together.
Signed-off-by: Andres Salomon <dilinger@queued.net> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
MyungJoo Ham [Thu, 23 Dec 2010 08:53:36 +0000 (17:53 +0900)]
mfd: MAX8998/LP3974 hibernation support
This patch makes the driver to save and restore register values
for hibernation.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Sat, 11 Dec 2010 13:07:49 +0000 (13:07 +0000)]
mfd: Remove ARCH_U8500 dependency from AB8500
While it is vanishingly unlikely that the device will be deployed on other
architectures removing the dependency facilitates build testing when doing
generic work on both the MFD core for the device and the subsystem drivers.
There appears to be no actual code dependency.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Mon, 20 Dec 2010 12:28:11 +0000 (12:28 +0000)]
misc: Make AB8500_PWM driver depend on U8500 due to PWM breakage
Since we don't have a PWM API every PWM driver ends up exporting its
own version and we need to limit the platforms we try to build them on
in order to avoid multiple definitions. As the AB8500 is normally a
companion chip for the U8500 CPU depend on that architecture.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Joe Perches [Mon, 20 Dec 2010 10:28:40 +0000 (11:28 +0100)]
gpio: Fix cs5535 printk warnings
drivers/gpio/cs5535-gpio.c: In function 'cs5535_gpio_probe':
drivers/gpio/cs5535-gpio.c:269: warning: format '%x' expects type 'unsigned int', but argument 3 has type 'resource_size_t'
drivers/gpio/cs5535-gpio.c:269: warning: format '%x' expects type 'unsigned int', but argument 4 has type 'resource_size_t'
Use vsprintf extension %pR to format resource.
Original-patch-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Joe Perches [Mon, 20 Dec 2010 10:26:19 +0000 (11:26 +0100)]
misc: Fix cs5535 printk warnings
drivers/misc/cs5535-mfgpt.c: In function 'cs5535_mfgpt_probe':
drivers/misc/cs5535-mfgpt.c:320: warning: format '%x' expects type 'unsigned int', but argument 3 has type 'resource_size_t'
drivers/misc/cs5535-mfgpt.c:320: warning: format '%x' expects type 'unsigned int', but argument 4 has type 'resource_size_t'
Use vsprintf extension %pR to format resource.
Original-patch-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Sun, 12 Dec 2010 12:39:28 +0000 (12:39 +0000)]
mfd: Convert tps6586x driver to new irq_ API
The genirq core is being updated to supply struct irq_data to irq_chip
operations rather than an irq number. Update the tps6586x driver to the
new APIs.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Mike Rapoport <mike@compulab.co.il> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Sun, 12 Dec 2010 12:34:04 +0000 (12:34 +0000)]
mfd: Convert tc6393xb driver to new irq_ APIs
The genirq core is being update to pass struct irq_data to irq_chip rather
than an irq number to operations. Update tc6393 to the new API.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Ian Molton <ian@mnementh.co.uk> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Sun, 12 Dec 2010 12:18:58 +0000 (12:18 +0000)]
mfd: Convert t7166xb driver to new irq_ API
The genirq core is being updated to pass struct irq_data rather than an
irq number to irq_chip operations. Update the t7166xb driver to the new
APIs.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Ian Molton <ian@mnementh.co.uk> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Sun, 12 Dec 2010 12:01:08 +0000 (12:01 +0000)]
mfd: Convert SMTPE driver to new irq_ APIs
The genirq core is being updated to supply struct irq_data to irq_chip
operations rather than an irq number. Update the SMTPE driver to the new
APIs.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Rabin Vincent <rabin.vincent@stericsson.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Sun, 12 Dec 2010 19:08:30 +0000 (20:08 +0100)]
mfd: Convert jz4740-adc to new irq_ methods
Convert the jz4740-adc driver to use the recently introduced IRQ API
variants which are passed struct irq_data rather than an IRQ number.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Sat, 11 Dec 2010 16:44:11 +0000 (16:44 +0000)]
mfd: Convert HTC I2C CPLD driver to irq_ API
The genirq core is being converted to pass a struct irq_data to interrupt
operations rather than an IRQ number.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Cory Maccarrone <darkstar6262@gmail.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Lennert Buytenhek <buytenh@secretlab.ca> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Sat, 11 Dec 2010 13:16:08 +0000 (13:16 +0000)]
mfd: Convert AB8500 to new irq_ methods
The genirq core is being converted to supply struct irq_data to chips
rather than the interrupt number.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Mattias Wallin <mattias.wallin@stericsson.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Sat, 11 Dec 2010 13:14:12 +0000 (13:14 +0000)]
mfd: Convert AB3500 to new irq_ APIs
The genirq core is being updated to pass struct irq_data rather than irq
numbers into chip drivers. As part of the update assignments to NULL for
unused operations are removed, these are not needed and the genirq docs
should be good enough.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Mattias Wallin <mattias.wallin@stericsson.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Sat, 11 Dec 2010 13:08:57 +0000 (13:08 +0000)]
mfd: Convert ASIC3 to new irq_ APIs
The interrupt controller APIs are being updated to pass a struct irq_data
rather than the interrupt number.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Ian Molton <ian@mnementh.co.uk> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Sat, 11 Dec 2010 16:44:49 +0000 (16:44 +0000)]
mfd: Staticise internal functions in HTC I2CCPLD driver
Most of these are GPIO operations, though a couple are just internal only
functions.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Cory Maccarrone <darkstar6262@gmail.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Mon, 13 Dec 2010 14:06:47 +0000 (14:06 +0000)]
mfd: Use NULL to initialise NULL pointers in ab8500-debugfs
Partly for coding style reasons, but mostly because sparse warns on it.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Mattias Wallin <mattias.wallin@stericsson.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Stephen Warren [Thu, 9 Dec 2010 17:30:11 +0000 (10:30 -0700)]
mfd: Remove tps6586x device ID check
... and convert it to a dev_info print at probe time.
There are many variants of this chip with different values of VERSIONCRC.
The set of values is large, and not useful to enumerate. All are SW
compatible. The difference lies in default settings of the various power
rails, and other similar differences. The driver, or clients of the
driver, shouldn't be affected by this, since all rails should be
programmed into the desired state in all cases for correct operation.
Derived-from-code-by: Andrew Chew <achew@nvidia.com> Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Andres Salomon [Tue, 30 Nov 2010 21:54:39 +0000 (13:54 -0800)]
mfd: Fix cs5535 warning on x86-64
ARRAY_SIZE() returns size_t; use %zu instead of %d so that we don't
get warnings on x86-64.
Signed-off-by: Andres Salomon <dilinger@queued.net> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Fri, 26 Nov 2010 17:19:35 +0000 (17:19 +0000)]
mfd: Implement runtime PM for WM8994 core driver
Allow the WM8994 to completely power off, including disabling the LDOs
if they are software controlled, when it goes idle. The CODEC subdevice
controls activity for the MFD as a whole.
If the GPIOs need to be used while the device is active runtime PM
should be disabled for the device by machine specific code.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Fri, 26 Nov 2010 17:19:34 +0000 (17:19 +0000)]
mfd: Provide pm_runtime_no_callbacks flag in cell data
Allow MFD cells to have pm_runtime_no_callbacks() called on them during
registration. This causes the runtime PM framework to ignore them,
allowing use of runtime PM to suspend the device as a whole even if
not all drivers for the MFD can usefully implement runtime PM. For
example, RTCs are likely to run continuously regardless of the power
state of the system.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Wed, 24 Nov 2010 18:01:44 +0000 (18:01 +0000)]
mfd: Convert WM8994 to new irq_ interrupt methods
Kernel 2.6.37 adds new interrupt methods which take a struct irq_data
rather than an irq number. Convert over to these as they will become
mandatory in future.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Wed, 24 Nov 2010 18:01:43 +0000 (18:01 +0000)]
mfd: Convert WM835x to new irq_ interrupt methods
Kernel 2.6.37 adds new interrupt methods which take a struct irq_data
rather than an irq number. Convert over to these as they will become
mandatory in future.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Mark Brown [Wed, 24 Nov 2010 18:01:42 +0000 (18:01 +0000)]
mfd: Convert WM831x to new irq_ interrupt methods
Kernel 2.6.37 adds new interrupt methods which take a struct irq_data
rather than an irq number. Convert over to these as they will become
mandatory in future.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Linus Torvalds [Fri, 14 Jan 2011 04:15:35 +0000 (20:15 -0800)]
Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (59 commits)
ACPI / PM: Fix build problems for !CONFIG_ACPI related to NVS rework
ACPI: fix resource check message
ACPI / Battery: Update information on info notification and resume
ACPI: Drop device flag wake_capable
ACPI: Always check if _PRW is present before trying to evaluate it
ACPI / PM: Check status of power resources under mutexes
ACPI / PM: Rename acpi_power_off_device()
ACPI / PM: Drop acpi_power_nocheck
ACPI / PM: Drop acpi_bus_get_power()
Platform / x86: Make fujitsu_laptop use acpi_bus_update_power()
ACPI / Fan: Rework the handling of power resources
ACPI / PM: Register power resource devices as soon as they are needed
ACPI / PM: Register acpi_power_driver early
ACPI / PM: Add function for updating device power state consistently
ACPI / PM: Add function for device power state initialization
ACPI / PM: Introduce __acpi_bus_get_power()
ACPI / PM: Introduce function for refcounting device power resources
ACPI / PM: Add functions for manipulating lists of power resources
ACPI / PM: Prevent acpi_power_get_inferred_state() from making changes
ACPICA: Update version to 20101209
...
Linus Torvalds [Fri, 14 Jan 2011 04:15:18 +0000 (20:15 -0800)]
Merge branch 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6
* 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6:
cpuidle/x86/perf: fix power:cpu_idle double end events and throw cpu_idle events from the cpuidle layer
intel_idle: open broadcast clock event
cpuidle: CPUIDLE_FLAG_CHECK_BM is omap3_idle specific
cpuidle: CPUIDLE_FLAG_TLB_FLUSHED is specific to intel_idle
cpuidle: delete unused CPUIDLE_FLAG_SHALLOW, BALANCED, DEEP definitions
SH, cpuidle: delete use of NOP CPUIDLE_FLAGS_SHALLOW
cpuidle: delete NOP CPUIDLE_FLAG_POLL
ACPI: processor_idle: delete use of NOP CPUIDLE_FLAGs
cpuidle: Rename X86 specific idle poll state[0] from C0 to POLL
ACPI, intel_idle: Cleanup idle= internal variables
cpuidle: Make cpuidle_enable_device() call poll_idle_init()
intel_idle: update Sandy Bridge core C-state residency targets
Linus Torvalds [Fri, 14 Jan 2011 04:14:13 +0000 (20:14 -0800)]
Merge branch 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin
* 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin:
fs: fix do_last error case when need_reval_dot
nfs: add missing rcu-walk check
fs: hlist UP debug fixup
fs: fix dropping of rcu-walk from force_reval_path
fs: force_reval_path drop rcu-walk before d_invalidate
fs: small rcu-walk documentation fixes
Fixed up trivial conflicts in Documentation/filesystems/porting
J. R. Okajima [Fri, 14 Jan 2011 03:56:04 +0000 (03:56 +0000)]
fs: fix do_last error case when need_reval_dot
When open(2) without O_DIRECTORY opens an existing dir, it should return
EISDIR. In do_last(), the variable 'error' is initialized EISDIR, but it
is changed by d_revalidate() which returns any positive to represent
'the target dir is valid.'
Should we keep and return the initialized 'error' in this case.
Linus Torvalds [Fri, 14 Jan 2011 02:46:48 +0000 (18:46 -0800)]
Merge branch 'stable/gntdev' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/gntdev' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/p2m: Fix module linking error.
xen p2m: clear the old pte when adding a page to m2p_override
xen gntdev: use gnttab_map_refs and gnttab_unmap_refs
xen: introduce gnttab_map_refs and gnttab_unmap_refs
xen p2m: transparently change the p2m mappings in the m2p override
xen/gntdev: Fix circular locking dependency
xen/gntdev: stop using "token" argument
xen: gntdev: move use of GNTMAP_contains_pte next to the map_op
xen: add m2p override mechanism
xen: move p2m handling to separate file
xen/gntdev: add VM_PFNMAP to vma
xen/gntdev: allow usermode to map granted pages
xen: define gnttab_set_map_op/unmap_op
Linus Torvalds [Fri, 14 Jan 2011 02:44:52 +0000 (18:44 -0800)]
Merge branch 'stable/platform-pci-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/platform-pci-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen-platform: Fix compile errors if CONFIG_PCI is not enabled.
xen: rename platform-pci module to xen-platform-pci.
xen-platform: use PCI interfaces to request IO and MEM resources.
Fix the expression, and also avoid a dependency between bit spinlock
implementation and list bl code (list code shouldn't know anything
except that bit 0 is set when adding and removing elements). Eventually
if a good use case comes up, we might use this list to store 1 or more
arbitrary bits of data, so it really shouldn't be tied to locking either,
but for now they are helpful for debugging.
Nick Piggin [Fri, 14 Jan 2011 02:36:19 +0000 (02:36 +0000)]
fs: fix dropping of rcu-walk from force_reval_path
As J. R. Okajima noted, force_reval_path passes in the same dentry to
d_revalidate as the one in the nameidata structure (other callers pass in a
child), so the locking breaks. This can oops with a chrooted nfs mount, for
example. Similarly there can be other problems with revalidating a dentry
which is already in nameidata of the path walk.
Nick Piggin [Fri, 14 Jan 2011 02:35:53 +0000 (02:35 +0000)]
fs: force_reval_path drop rcu-walk before d_invalidate
d_revalidate can return in rcu-walk mode even when it returns 0. We can't just
call any old dcache function on rcu-walk dentry (the dentry is unstable, so
even through d_lock can safely be taken, the result may no longer be what we
expect -- careful re-checks would be required). So just drop rcu in this case.
(I missed this conversion when switching to the rcu-walk convention that Linus
suggested)
In the current implementation mem_cgroup_end_migration() decides whether
the page migration has succeeded or not by checking "oldpage->mapping".
But if we are tring to migrate a shmem swapcache, the page->mapping of it
is NULL from the begining, so the check would be invalid. As a result,
mem_cgroup_end_migration() assumes the migration has succeeded even if
it's not, so "newpage" would be freed while it's not uncharged.
This patch fixes it by passing mem_cgroup_end_migration() the result of
the page migration.
Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: Minchan Kim <minchan.kim@gmail.com> Reviewed-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jesper Juhl [Thu, 13 Jan 2011 23:47:42 +0000 (15:47 -0800)]
memcg: use [kv]zalloc[_node] rather than [kv]malloc+memset
In mem_cgroup_alloc() we currently do either kmalloc() or vmalloc() then
followed by memset() to zero the memory. This can be more efficiently
achieved by using kzalloc() and vzalloc(). There's also one situation
where we can use kzalloc_node() - this is what's new in this version of
the patch.
Commit b1dd693e ("memcg: avoid deadlock between move charge and
try_charge()") can cause another deadlock about mmap_sem on task migration
if cpuset and memcg are mounted onto the same mount point.
After the commit, cgroup_attach_task() has sequence like:
We can cause deadlock at (2) because we've already aquire the mmap_sem at (1).
But the commit itself is necessary to fix deadlocks which have existed
before the commit like:
Ex.1)
move charge | try charge
--------------------------------------+------------------------------
mem_cgroup_can_attach() | down_write(&mmap_sem)
mc.moving_task = current | ..
mem_cgroup_precharge_mc() | __mem_cgroup_try_charge()
mem_cgroup_count_precharge() | prepare_to_wait()
down_read(&mmap_sem) | if (mc.moving_task)
-> cannot aquire the lock | -> true
| schedule()
| -> move charge should wake it up
Ex.2)
move charge | try charge
--------------------------------------+------------------------------
mem_cgroup_can_attach() |
mc.moving_task = current |
mem_cgroup_precharge_mc() |
mem_cgroup_count_precharge() |
down_read(&mmap_sem) |
.. |
up_read(&mmap_sem) |
| down_write(&mmap_sem)
mem_cgroup_move_task() | ..
mem_cgroup_move_charge() | __mem_cgroup_try_charge()
down_read(&mmap_sem) | prepare_to_wait()
-> cannot aquire the lock | if (mc.moving_task)
| -> true
| schedule()
| -> move charge should wake it up
This patch fixes all of these problems by:
1. revert the commit.
2. To fix the Ex.1, we set mc.moving_task after mem_cgroup_count_precharge()
has released the mmap_sem.
3. To fix the Ex.2, we use down_read_trylock() instead of down_read() in
mem_cgroup_move_charge() and, if it has failed to aquire the lock, cancel
all extra charges, wake up all waiters, and retry trylock.
Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Reported-by: Ben Blum <bblum@andrew.cmu.edu> Cc: Miao Xie <miaox@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Paul Menage <menage@google.com> Cc: Hiroyuki Kamezawa <kamezawa.hiroyuki@gmail.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Thu, 13 Jan 2011 23:47:39 +0000 (15:47 -0800)]
memcg: fix unit mismatch in memcg oom limit calculation
Adding the number of swap pages to the byte limit of a memory control
group makes no sense. Convert the pages to bytes before adding them.
The only user of this code is the OOM killer, and the way it is used means
that the error results in a higher OOM badness value. Since the cgroup
limit is the same for all tasks in the cgroup, the error should have no
practical impact at the moment.
But let's not wait for future or changing users to trip over it.
memcg: add lock to synchronize page accounting and migration
Introduce a new bit spin lock, PCG_MOVE_LOCK, to synchronize the page
accounting and migration code. This reworks the locking scheme of
_update_stat() and _move_account() by adding new lock bit PCG_MOVE_LOCK,
which is always taken under IRQ disable.
1. If pages are being migrated from a memcg, then updates to that
memcg page statistics are protected by grabbing PCG_MOVE_LOCK using
move_lock_page_cgroup(). In an upcoming commit, memcg dirty page
accounting will be updating memcg page accounting (specifically: num
writeback pages) from IRQ context (softirq). Avoid a deadlocking
nested spin lock attempt by disabling irq on the local processor when
grabbing the PCG_MOVE_LOCK.
2. lock for update_page_stat is used only for avoiding race with
move_account(). So, IRQ awareness of lock_page_cgroup() itself is not
a problem. The problem is between mem_cgroup_update_page_stat() and
mem_cgroup_move_account_page().
Trade-off:
* Changing lock_page_cgroup() to always disable IRQ (or
local_bh) has some impacts on performance and I think
it's bad to disable IRQ when it's not necessary.
* adding a new lock makes move_account() slower. Score is
here.
Performance Impact: moving a 8G anon process.
Before:
real 0m0.792s
user 0m0.000s
sys 0m0.780s
After:
real 0m0.854s
user 0m0.000s
sys 0m0.842s
This score is bad but planned patches for optimization can reduce
this impact.
Greg Thelen [Thu, 13 Jan 2011 23:47:37 +0000 (15:47 -0800)]
memcg: create extensible page stat update routines
Replace usage of the mem_cgroup_update_file_mapped() memcg
statistic update routine with two new routines:
* mem_cgroup_inc_page_stat()
* mem_cgroup_dec_page_stat()
As before, only the file_mapped statistic is managed. However, these more
general interfaces allow for new statistics to be more easily added. New
statistics are added with memcg dirty page accounting.
Greg Thelen [Thu, 13 Jan 2011 23:47:35 +0000 (15:47 -0800)]
memcg: add page_cgroup flags for dirty page tracking
This patchset provides the ability for each cgroup to have independent
dirty page limits.
Limiting dirty memory is like fixing the max amount of dirty (hard to
reclaim) page cache used by a cgroup. So, in case of multiple cgroup
writers, they will not be able to consume more than their designated share
of dirty pages and will be forced to perform write-out if they cross that
limit.
The patches are based on a series proposed by Andrea Righi in Mar 2010.
Overview:
- Add page_cgroup flags to record when pages are dirty, in writeback, or nfs
unstable.
- Extend mem_cgroup to record the total number of pages in each of the
interesting dirty states (dirty, writeback, unstable_nfs).
- Add dirty parameters similar to the system-wide /proc/sys/vm/dirty_*
limits to mem_cgroup. The mem_cgroup dirty parameters are accessible
via cgroupfs control files.
- Consider both system and per-memcg dirty limits in page writeback when
deciding to queue background writeback or block for foreground writeback.
Known shortcomings:
- When a cgroup dirty limit is exceeded, then bdi writeback is employed to
writeback dirty inodes. Bdi writeback considers inodes from any cgroup, not
just inodes contributing dirty pages to the cgroup exceeding its limit.
- When memory.use_hierarchy is set, then dirty limits are disabled. This is a
implementation detail. An enhanced implementation is needed to check the
chain of parents to ensure that no dirty limit is exceeded.
Performance data:
- A page fault microbenchmark workload was used to measure performance, which
can be called in read or write mode:
f = open(foo. $cpu)
truncate(f, 4096)
alarm(60)
while (1) {
p = mmap(f, 4096)
if (write)
*p = 1
else
x = *p
munmap(p)
}
- The workload was called for several points in the patch series in different
modes:
- s_read is a single threaded reader
- s_write is a single threaded writer
- p_read is a 16 thread reader, each operating on a different file
- p_write is a 16 thread writer, each operating on a different file
- Measurements were collected on a 16 core non-numa system using "perf stat
--repeat 3". The -a option was used for parallel (p_*) runs.
- All numbers are page fault rate (M/sec). Higher is better.
- To compare the performance of a kernel without non-memcg compare the first and
last rows, neither has memcg configured. The first row does not include any
of these memcg patches.
- To compare the performance of using memcg dirty limits, compare the baseline
(2nd row titled "w/ memcg") with the the code and memcg enabled (2nd to last
row titled "all patches").
Shaohua Li [Thu, 13 Jan 2011 23:47:34 +0000 (15:47 -0800)]
mm: batch activate_page() to reduce lock contention
The zone->lru_lock is heavily contented in workload where activate_page()
is frequently used. We could do batch activate_page() to reduce the lock
contention. The batched pages will be added into zone list when the pool
is full or page reclaim is trying to drain them.
For example, in a 4 socket 64 CPU system, create a sparse file and 64
processes, processes shared map to the file. Each process read access the
whole file and then exit. The process exit will do unmap_vmas() and cause
a lot of activate_page() call. In such workload, we saw about 58% total
time reduction with below patch. Other workloads with a lot of
activate_page also benefits a lot too.
Hugh Dickins [Thu, 13 Jan 2011 23:47:31 +0000 (15:47 -0800)]
mm: fix hugepage migration
2.6.37 added an unmap_and_move_huge_page() for memory failure recovery,
but its anon_vma handling was still based around the 2.6.35 conventions.
Update it to use page_lock_anon_vma, get_anon_vma, page_unlock_anon_vma,
drop_anon_vma in the same way as we're now changing unmap_and_move().
I don't particularly like to propose this for stable when I've not seen
its problems in practice nor tested the solution: but it's clearly out of
synch at present.
Hugh Dickins [Thu, 13 Jan 2011 23:47:30 +0000 (15:47 -0800)]
mm: fix migration hangs on anon_vma lock
Increased usage of page migration in mmotm reveals that the anon_vma
locking in unmap_and_move() has been deficient since 2.6.36 (or even
earlier). Review at the time of f18194275c39835cb84563500995e0d503a32d9a
("mm: fix hang on anon_vma->root->lock") missed the issue here: the
anon_vma to which we get a reference may already have been freed back to
its slab (it is in use when we check page_mapped, but that can change),
and so its anon_vma->root may be switched at any moment by reuse in
anon_vma_prepare.
Perhaps we could fix that with a get_anon_vma_unless_zero(), but let's
not: just rely on page_lock_anon_vma() to do all the hard thinking for us,
then we don't need any rcu read locking over here.
In removing the rcu_unlock label: since PageAnon is a bit in
page->mapping, it's impossible for a !page->mapping page to be anon; but
insert VM_BUG_ON in case the implementation ever changes.
Eric B Munson [Thu, 13 Jan 2011 23:47:28 +0000 (15:47 -0800)]
hugetlb: fix handling of parse errors in sysfs
When parsing changes to the huge page pool sizes made from userspace via
the sysfs interface, bogus input values are being covered up by
nr_hugepages_store_common and nr_overcommit_hugepages_store returning 0
when strict_strtoul returns an error. This can cause an infinite loop in
the nr_hugepages_store code. This patch changes the return value for
these functions to -EINVAL when strict_strtoul returns an error.
Signed-off-by: Eric B Munson <emunson@mgebm.net> Reported-by: CAI Qian <caiqian@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Eric B Munson <emunson@mgebm.net> Cc: Michal Hocko <mhocko@suse.cz> Cc: Nishanth Aravamudan <nacc@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Eric B Munson [Thu, 13 Jan 2011 23:47:27 +0000 (15:47 -0800)]
hugetlb: do not allow pagesize >= MAX_ORDER pool adjustment
Huge pages with order >= MAX_ORDER must be allocated at boot via the
kernel command line, they cannot be allocated or freed once the kernel is
up and running. Currently we allow values to be written to the sysfs and
sysctl files controling pool size for these huge page sizes. This patch
makes the store functions for nr_hugepages and nr_overcommit_hugepages
return -EINVAL when the pool for a page size >= MAX_ORDER is changed.
[akpm@linux-foundation.org: avoid multiple return paths in nr_hugepages_store_common()]
[caiqian@redhat.com: add checking in hugetlb_overcommit_handler()] Signed-off-by: Eric B Munson <emunson@mgebm.net> Reported-by: CAI Qian <caiqian@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Nishanth Aravamudan <nacc@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Thu, 13 Jan 2011 23:47:26 +0000 (15:47 -0800)]
hugetlb: check the return value of string conversion in sysctl handler
proc_doulongvec_minmax may fail if the given buffer doesn't represent a
valid number. If we provide something invalid we will initialize the
resulting value (nr_overcommit_huge_pages in this case) to a random value
from the stack.
The issue was introduced by a3d0c6aa when the default handler has been
replaced by the helper function where we do not check the return value.
mm/dmapool.c: take lock only once in dma_pool_free()
dma_pool_free() scans for the page to free in the pool list holding the
pool lock. Then it releases the lock basically to acquire it immediately
again. Modify the code to only take the lock once.
This will do some additional loops and computations with the lock held in
if memory debugging is activated. If it is not activated the only new
operations with this lock is one if and one substraction.
Jiri Kosina [Thu, 13 Jan 2011 23:47:23 +0000 (15:47 -0800)]
brk: fix min_brk lower bound computation for COMPAT_BRK
Even if CONFIG_COMPAT_BRK is set in the kernel configuration, it can still
be overriden by randomize_va_space sysctl.
If this is the case, the min_brk computation in sys_brk() implementation
is wrong, as it solely takes into account COMPAT_BRK setting, assuming
that brk start is not randomized. But that might not be the case if
randomize_va_space sysctl has been set to '2' at the time the binary has
been loaded from disk.
In such case, the check has to be done in a same way as in
!CONFIG_COMPAT_BRK case.
In addition to that, the check for the COMPAT_BRK case introduced back in a5b4592c ("brk: make sys_brk() honor COMPAT_BRK when computing lower
bound") is slightly wrong -- the lower bound shouldn't be mm->end_code,
but mm->end_data instead, as that's where the legacy applications expect
brk section to start (i.e. immediately after last global variable).
Jesper Juhl [Thu, 13 Jan 2011 23:47:22 +0000 (15:47 -0800)]
mm/hugetlb.c: fix error-path memory leak in nr_hugepages_store_common()
The NODEMASK_ALLOC macro may dynamically allocate memory for its second
argument ('nodes_allowed' in this context).
In nr_hugepages_store_common() we may abort early if strict_strtoul()
fails, but in that case we do not free the memory already allocated to
'nodes_allowed', causing a memory leak.
This patch closes the leak by freeing the memory in the error path.
[akpm@linux-foundation.org: use NODEMASK_FREE, per Minchan Kim] Signed-off-by: Jesper Juhl <jj@chaosbits.net> Cc: Minchan Kim <minchan.kim@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 13 Jan 2011 23:47:21 +0000 (15:47 -0800)]
mm: migration: use rcu_dereference_protected when dereferencing the radix tree slot during file page migration
migrate_pages() -> unmap_and_move() only calls rcu_read_lock() for
anonymous pages, as introduced by git commit 989f89c57e6361e7d16fbd9572b5da7d313b073d ("fix rcu_read_lock() in page
migraton"). The point of the RCU protection there is part of getting a
stable reference to anon_vma and is only held for anon pages as file pages
are locked which is sufficient protection against freeing.
However, while a file page's mapping is being migrated, the radix tree is
double checked to ensure it is the expected page. This uses
radix_tree_deref_slot() -> rcu_dereference() without the RCU lock held
triggering the following warning.
This patch introduces radix_tree_deref_slot_protected() which calls
rcu_dereference_protected(). Users of it must pass in the
mapping->tree_lock that is protecting this dereference. Holding the tree
lock protects against parallel updaters of the radix tree meaning that
rcu_dereference_protected is allowable.
[akpm@linux-foundation.org: remove unneeded casts] Signed-off-by: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Milton Miller <miltonm@bga.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: <stable@kernel.org> [2.6.37.early] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrea Arcangeli [Thu, 13 Jan 2011 23:47:19 +0000 (15:47 -0800)]
thp: KSM on THP
This makes KSM full operational with THP pages. Subpages are scanned
while the hugepage is still in place and delivering max cpu performance,
and only if there's a match and we're going to deduplicate memory, the
single hugepages with the subpage match is split.
There will be no false sharing between ksmd and khugepaged. khugepaged
won't collapse 2m virtual regions with KSM pages inside. ksmd also should
only split pages when the checksum matches and we're likely to split an
hugepage for some long living ksm page (usual ksm heuristic to avoid
sharing pages that get de-cowed).
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrea Arcangeli [Thu, 13 Jan 2011 23:47:18 +0000 (15:47 -0800)]
thp: khugepaged: make khugepaged aware about madvise
MADV_HUGEPAGE and MADV_NOHUGEPAGE were fully effective only if run after
mmap and before touching the memory. While this is enough for most
usages, it's little effort to make madvise more dynamic at runtime on an
existing mapping by making khugepaged aware about madvise.
MADV_HUGEPAGE: register in khugepaged immediately without waiting a page
fault (that may not ever happen if all pages are already mapped and the
"enabled" knob was set to madvise during the initial page faults).
MADV_NOHUGEPAGE: skip vmas marked VM_NOHUGEPAGE in khugepaged to stop
collapsing pages where not needed.
[akpm@linux-foundation.org: tweak comment] Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrea Arcangeli [Thu, 13 Jan 2011 23:47:17 +0000 (15:47 -0800)]
thp: madvise(MADV_NOHUGEPAGE)
Add madvise MADV_NOHUGEPAGE to mark regions that are not important to be
hugepage backed. Return -EINVAL if the vma is not of an anonymous type,
or the feature isn't built into the kernel. Never silently return
success.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrea Arcangeli [Thu, 13 Jan 2011 23:47:16 +0000 (15:47 -0800)]
thp: fix memory-failure hugetlbfs vs THP collision
hugetlbfs was changed to allow memory failure to migrate the hugetlbfs
pages and that broke THP as split_huge_page was then called on hugetlbfs
pages too.
compound_head/order was also run unsafe on THP pages that can be splitted
at any time.
All compound_head() invocations in memory-failure.c that are run on pages
that aren't pinned and that can be freed and reused from under us (while
compound_head is running) are buggy because compound_head can return a
dangling pointer, but I'm not fixing this as this is a generic
memory-failure bug not specific to THP but it applies to hugetlbfs too, so
I can fix it later after THP is merged upstream.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>