Commit Graph

20500 Commits

Author SHA1 Message Date
Todd Fischer d183fcc975 mfd: Move TPS6507x register definition to header file.
Other sub-drivers for the TPS6507x chip will need to use register
definition so move it out of the source file and into a header file.

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>
2010-05-28 01:37:36 +02:00
Ira W. Snyder bd3581323c 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>
2010-05-28 01:37:32 +02:00
Henrik Kretzschmar 872c1b14e7 mfd: Section cleanup of 88pm860x driver
This patch fixes three section mismatches.

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>
2010-05-28 01:37:31 +02:00
Florian Fainelli e090d506c3 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>
2010-05-28 01:37:28 +02:00
Linus Torvalds c5617b200a 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
  ...
2010-05-27 15:23:47 -07:00
Linus Torvalds cad719d86e Merge branch 'for-linus' of git://git.o-hand.com/linux-rpurdie-backlight
* 'for-linus' of git://git.o-hand.com/linux-rpurdie-backlight:
  gta02: Use pcf50633 backlight driver instead of platform backlight driver.
  backlight: pcf50633: Register a pcf50633-backlight device in pcf50633 core driver.
  backlight: Add pcf50633 backlight driver
  backlight: 88pm860x_bl: fix error handling in pm860x_backlight_probe
  backlight: max8925_bl: Fix error handling path
  backlight: l4f00242t03: fix error handling in l4f00242t03_probe
  backlight: add S6E63M0 AMOLED LCD Panel driver
  backlight: adp8860: add support for ADP8861 & ADP8863
  backlight: mbp_nvidia_bl - Fix DMI_SYS_VENDOR for MacBook1,1
  backlight: Add Cirrus EP93xx backlight driver
  backlight: l4f00242t03: Fix regulators handling code in remove function
  backlight: fix adp8860_bl build errors
  backlight: new driver for the ADP8860 backlight parts
  backlight: 88pm860x_bl - potential memory leak
  backlight: mbp_nvidia_bl - add support for older MacBookPro and MacBook 6,1.
  backlight: Kconfig cleanup
  backlight: backlight_device_register() return ERR_PTR()
2010-05-27 11:34:55 -07:00
Linus Torvalds 3ddab4788d 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
2010-05-27 11:34:20 -07:00
Linus Torvalds d1e0fe252e 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
  ...
2010-05-27 11:33:46 -07:00
Jean Delvare 70dd6beac0 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>
2010-05-27 19:58:37 +02:00
Linus Torvalds 4e455c6782 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
2010-05-27 10:47:41 -07:00
Linus Torvalds 105a048a4f Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* 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
  ...
2010-05-27 10:43:44 -07:00
Linus Torvalds e4ce30f377 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
  ...

Fixed up trivial conflict in fs/ext4/fsync.c
2010-05-27 10:26:37 -07:00
Linus Torvalds 55ddf14b04 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
2010-05-27 10:22:06 -07:00
Linus Torvalds 7eb1053fd0 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)
2010-05-27 09:19:55 -07:00
Lee Schermerhorn 7aac789885 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>
2010-05-27 09:12:57 -07:00
Lee Schermerhorn 7281201922 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>
2010-05-27 09:12:57 -07:00
jan Blunck ae6afc3f5c 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>
2010-05-27 09:12:56 -07:00
Jeff Moyer 9d85cba718 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>
2010-05-27 09:12:53 -07:00
Jeff Moyer b83733639a compat: factor out compat_rw_copy_check_uvector from compat_do_readv_writev
It was reported in http://lkml.org/lkml/2010/3/8/309 that 32 bit readv and
writev AIO operations were not functioning properly.  It turns out that
the code to convert the 32bit io vectors to 64 bits was never written.
The results of that can be pretty bad, but in my testing, it mostly ended
up in generating EFAULT as we walked off the list of I/O vectors provided.

This patch set fixes the problem in my environment.  are greatly
appreciated.

This patch:

Factor out code that will be used by both compat_do_readv_writev and the
compat aio submission code paths.

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>
2010-05-27 09:12:53 -07:00
FUJITA Tomonori 99d1bd2c13 dma-mapping: remove deprecated dma_sync_single and dma_sync_sg API
Since 2.6.5, it had been commented, 'for backwards compatibility,
removed in 2.7.x'. Since 2.6.31, it have been marked as __deprecated.

I think that we can remove the API safely now.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:53 -07:00
FUJITA Tomonori 5fd75a7850 dma-mapping: remove unnecessary sync_single_range_* in dma_map_ops
sync_single_range_for_cpu and sync_single_range_for_device hooks are
unnecessary because sync_single_for_cpu and sync_single_for_device can
be used instead.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:52 -07:00
FUJITA Tomonori 38388301b7 swiotlb: remove unnecessary swiotlb_sync_single_range_*
swiotlb_sync_single_range_for_cpu and swiotlb_sync_single_range_for_device
are unnecessary because swiotlb_sync_single_for_cpu and
swiotlb_sync_single_for_device can be used instead.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:52 -07:00
Joe Eykholt 5960164fde lib/random32: export pseudo-random number generator for modules
This patch moves the definition of struct rnd_state and the inline
__seed() function to linux/random.h.  It renames the static __random32()
function to prandom32() and exports it for use in modules.

prandom32() is useful as a privately-seeded pseudo random number generator
that can give the same result every time it is initialized.

For FCoE FC-BB-6 VN2VN mode self-selected unique FC address generation, we
need an pseudo-random number generator seeded with the 64-bit world-wide
port name.  A truly random generator or one seeded with randomness won't
do because the same sequence of numbers should be generated each time we
boot or the link comes up.

A prandom32_seed() inline function is added to the header file.  It is
inlined not for speed, but so the function won't be expanded in the base
kernel, but only in the module that uses it.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Acked-by: Matt Mackall <mpm@selenic.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:52 -07:00
Oleg Nesterov 0a14a130ca INIT_SIGHAND: use SIG_DFL instead of NULL
Cosmetic, no changes in the compiled code. Just s/NULL/SIG_DFL/ to make
it more readable and grep-friendly.

Note: probably SIG_IGN makes more sense, we could kill ignore_signals().
But then kernel_init() should do flush_signal_handlers() before exec().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Mathias Krause <Mathias.Krause@secunet.com>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:52 -07:00
Oleg Nesterov f20011457f pids: init_struct_pid.tasks should never see the swapper process
"statically initialize struct pid for swapper" commit 820e45db says:

	Statically initialize a struct pid for the swapper process (pid_t == 0)
	and attach it to init_task.  This is needed so task_pid(), task_pgrp()
	and task_session() interfaces work on the swapper process also.

OK, but:

	- it doesn't make sense to add init_task.pids[].node into
	  init_struct_pid.tasks[], and in fact this just wrong.

	  idle threads are special, they shouldn't be visible on any
	  global list. In particular do_each_pid_task(init_struct_pid)
	  shouldn't see swapper.

	  This is the actual reason why kill(0, SIGKILL) from /sbin/init
	  (which starts with 0,0 special pids) crashes the kernel. The
	  signal sent to pgid/sid == 0 must never see idle threads, even
	  if the previous patch fixed the crash itself.

	- we have other idle threads running on the non-boot CPUs, see
	  the next patch.

Change INIT_STRUCT_PID/INIT_PID_LINK to create the empty/unhashed
hlist_head/hlist_node. Like any other idle thread swapper can never exit,
so detach_pid()->__hlist_del() is not possible, but we could change
INIT_PID_LINK() to set pprev = &next if needed.

All we need is the valid swapper->pids[].pid == &init_struct_pid.

Reported-by: Mathias Krause <mathias.krause@secunet.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Mathias Krause <Mathias.Krause@secunet.com>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:52 -07:00
Oleg Nesterov fa2755e20a INIT_TASK() should initialize ->thread_group list
The trivial /sbin/init doing

	int main(void)
	{
		kill(0, SIGKILL)
	}

crashes the kernel.

This happens because __kill_pgrp_info(init_struct_pid) also sends SIGKILL
to the swapper process which runs with the uninitialized ->thread_group.

Change INIT_TASK() to initialize ->thread_group properly.

Note: the real problem is that the swapper process must not be visible to
signals, see the next patch. But this change is right anyway and fixes
the crash.

Reported-and-tested-by: Mathias Krause <mathias.krause@secunet.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Mathias Krause <Mathias.Krause@secunet.com>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:51 -07:00
Hedi Berriche 72680a191b pids: increase pid_max based on num_possible_cpus
On a system with a substantial number of processors, the early default
pid_max of 32k will not be enough.  A system with 1664 CPU's, there are
25163 processes started before the login prompt.  It's estimated that with
2048 CPU's we will pass the 32k limit.  With 4096, we'll reach that limit
very early during the boot cycle, and processes would stall waiting for an
available pid.

This patch increases the early maximum number of pids available, and
increases the minimum number of pids that can be set during runtime.

[akpm@linux-foundation.org: fix warnings]
Signed-off-by: Hedi Berriche <hedi@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Robin Holt <holt@sgi.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Greg KH <gregkh@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: John Stoffel <john@stoffel.org>
Cc: Jack Steiner <steiner@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:51 -07:00
Alexandre Bounine 7a88d62862 rapidio: add switch domain routines
Add switch specific domain routines required for 16-bit routing support in
switches with hierarchical implementation of routing tables.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:51 -07:00
Alexandre Bounine 058f88d672 rapidio: modify initialization of switch operations
Modify the way how RapidIO switch operations are declared.  Multiple
assignments through the linker script replaced by single initialization
call.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:51 -07:00
Thomas Moll 933af4a6c4 rapidio: add enabling SRIO port RX and TX
Add the functionality to enable Input receiver and Output transmitter of
every port, to allow non-maintenance traffic.

Signed-off-by: Thomas Moll <thomas.moll@sysgo.com>
Signed-off-by: Alexandre Bounine <abounine@tundra.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:51 -07:00
Alexandre Bounine e5cabeb3d6 rapidio: add Port-Write handling for EM
Add RapidIO Port-Write message handling in the context of Error
   Management Extensions Specification Rev.1.3.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Tested-by: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:50 -07:00
Alexandre Bounine 07590ff039 rapidio: add IDT CPS/TSI switches
Extentions to RapidIO switch support:

1. modify switch route operation declarations to allow using single
   switch-specific file for family of switches that share the same route
   table operations.

2. add standard route table operations for switches that that support
   route table manipulation registers as defined in the Rev.1.3 of RapidIO
   specification.

3. add clear-route-table operation for switches

4. add CPSxx and TSIxxx families of RapidIO switches

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Tested-by: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:50 -07:00
Manfred Spraul 31a7c4746e ipc/sem.c: cacheline align the ipc spinlock for semaphores
Cacheline align the spinlock for sysv semaphores.  Without the patch, the
spinlock and sem_otime [written by every semop that modified the array]
and sem_base [read in the hot path of try_atomic_semop()] can be in the
same cacheline.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:49 -07:00
Akinobu Mita b957e043ee notifier: change notifier_from_errno(0) to return NOTIFY_OK
This changes notifier_from_errno(0) to be NOTIFY_OK instead of
NOTIFY_STOP_MASK | NOTIFY_OK.

Currently, the notifiers which return encapsulated errno value have to
do something like this:

	err = do_something(); // returns -errno
	if (err)
		return notifier_from_errno(err);
	else
		return NOTIFY_OK;

This change makes the above code simple:

	err = do_something(); // returns -errno

	return return notifier_from_errno(err);

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:47 -07:00
Oleg Nesterov b3ac022cb9 proc: turn signal_struct->count into "int nr_threads"
No functional changes, just s/atomic_t count/int nr_threads/.

With the recent changes this counter has a single user, get_nr_threads()
And, none of its callers need the really accurate number of threads, not
to mention each caller obviously races with fork/exit.  It is only used to
report this value to the user-space, except first_tid() uses it to avoid
the unnecessary while_each_thread() loop in the unlikely case.

It is a bit sad we need a word in struct signal_struct for this, perhaps
we can change get_nr_threads() to approximate the number of threads using
signal->live and kill ->nr_threads later.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:47 -07:00
Oleg Nesterov 7e49827cc9 proc: get_nr_threads() doesn't need ->siglock any longer
Now that task->signal can't go away get_nr_threads() doesn't need
->siglock to read signal->count.

Also, make it inline, move into sched.h, and convert 2 other proc users of
signal->count to use this (now trivial) helper.

Henceforth get_nr_threads() is the only valid user of signal->count, we
are ready to turn it into "int nr_threads" or, perhaps, kill it.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:47 -07:00
Oleg Nesterov a705be6b5e kill the obsolete thread_group_cputime_free() helper
Kill the empty thread_group_cputime_free() helper.  It was needed to free
the per-cpu data which we no longer have.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Veaceslav Falico <vfalico@redhat.com>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:46 -07:00
Oleg Nesterov b7b8ff6373 signals: kill the awful task_rq_unlock_wait() hack
Now that task->signal can't go away we can revert the horrible hack added
by ad474caca3 ("fix for
account_group_exec_runtime(), make sure ->signal can't be freed under
rq->lock").

And we can do more cleanups sched_stats.h/posix-cpu-timers.c later.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:46 -07:00
Oleg Nesterov ea6d290ca3 signals: make task_struct->signal immutable/refcountable
We have a lot of problems with accessing task_struct->signal, it can
"disappear" at any moment.  Even current can't use its ->signal safely
after exit_notify().  ->siglock helps, but it is not convenient, not
always possible, and sometimes it makes sense to use task->signal even
after this task has already dead.

This patch adds the reference counter, sigcnt, into signal_struct.  This
reference is owned by task_struct and it is dropped in
__put_task_struct().  Perhaps it makes sense to export
get/put_signal_struct() later, but currently I don't see the immediate
reason.

Rename __cleanup_signal() to free_signal_struct() and unexport it.  With
the previous changes it does nothing except kmem_cache_free().

Change __exit_signal() to not clear/free ->signal, it will be freed when
the last reference to any thread in the thread group goes away.

Note:
	- when the last thead exits signal->tty can point to nowhere, see
	  the next patch.

	- with or without this patch signal_struct->count should go away,
	  or at least it should be "int nr_threads" for fs/proc. This will
	  be addressed later.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:46 -07:00
Oleg Nesterov 09faef11df exit: change zap_other_threads() to count sub-threads
Change zap_other_threads() to return the number of other sub-threads found
on ->thread_group list.

Other changes are cosmetic:

	- change the code to use while_each_thread() helper

	- remove the obsolete comment about SIGKILL/SIGSTOP

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:46 -07:00
Oleg Nesterov c70a626d3e umh: creds: kill subprocess_info->cred logic
Now that nobody ever changes subprocess_info->cred we can kill this member
and related code.  ____call_usermodehelper() always runs in the context of
freshly forked kernel thread, it has the proper ->cred copied from its
parent kthread, keventd.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:45 -07:00
Oleg Nesterov 685bfd2c48 umh: creds: convert call_usermodehelper_keys() to use subprocess_info->init()
call_usermodehelper_keys() uses call_usermodehelper_setkeys() to change
subprocess_info->cred in advance.  Now that we have info->init() we can
change this code to set tgcred->session_keyring in context of execing
kernel thread.

Note: since currently call_usermodehelper_keys() is never called with
UMH_NO_WAIT, call_usermodehelper_keys()->key_get() and umh_keys_cleanup()
are not really needed, we could rely on install_session_keyring_to_cred()
which does key_get() on success.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:45 -07:00
Neil Horman 898b374af6 exec: replace call_usermodehelper_pipe with use of umh init function and resolve limit
The first patch in this series introduced an init function to the
call_usermodehelper api so that processes could be customized by caller.
This patch takes advantage of that fact, by customizing the helper in
do_coredump to create the pipe and set its core limit to one (for our
recusrsion check).  This lets us clean up the previous uglyness in the
usermodehelper internals and factor call_usermodehelper out entirely.
While I'm at it, we can also modify the helper setup to look for a core
limit value of 1 rather than zero for our recursion check

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:44 -07:00
Neil Horman a06a4dc3a0 kmod: add init function to usermodehelper
About 6 months ago, I made a set of changes to how the core-dump-to-a-pipe
feature in the kernel works.  We had reports of several races, including
some reports of apps bypassing our recursion check so that a process that
was forked as part of a core_pattern setup could infinitely crash and
refork until the system crashed.

We fixed those by improving our recursion checks.  The new check basically
refuses to fork a process if its core limit is zero, which works well.

Unfortunately, I've been getting grief from maintainer of user space
programs that are inserted as the forked process of core_pattern.  They
contend that in order for their programs (such as abrt and apport) to
work, all the running processes in a system must have their core limits
set to a non-zero value, to which I say 'yes'.  I did this by design, and
think thats the right way to do things.

But I've been asked to ease this burden on user space enough times that I
thought I would take a look at it.  The first suggestion was to make the
recursion check fail on a non-zero 'special' number, like one.  That way
the core collector process could set its core size ulimit to 1, and enable
the kernel's recursion detection.  This isn't a bad idea on the surface,
but I don't like it since its opt-in, in that if a program like abrt or
apport has a bug and fails to set such a core limit, we're left with a
recursively crashing system again.

So I've come up with this.  What I've done is modify the
call_usermodehelper api such that an extra parameter is added, a function
pointer which will be called by the user helper task, after it forks, but
before it exec's the required process.  This will give the caller the
opportunity to get a call back in the processes context, allowing it to do
whatever it needs to to the process in the kernel prior to exec-ing the
user space code.  In the case of do_coredump, this callback is ues to set
the core ulimit of the helper process to 1.  This elimnates the opt-in
problem that I had above, as it allows the ulimit for core sizes to be set
to the value of 1, which is what the recursion check looks for in
do_coredump.

This patch:

Create new function call_usermodehelper_fns() and allow it to assign both
an init and cleanup function, as we'll as arbitrary data.

The init function is called from the context of the forked process and
allows for customization of the helper process prior to calling exec.  Its
return code gates the continuation of the process, or causes its exit.
Also add an arbitrary data pointer to the subprocess_info struct allowing
for data to be passed from the caller to the new process, and the
subsequent cleanup process

Also, use this patch to cleanup the cleanup function.  It currently takes
an argp and envp pointer for freeing, which is ugly.  Lets instead just
make the subprocess_info structure public, and pass that to the cleanup
and init routines

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:44 -07:00
Jack Steiner 0ac0c0d0f8 cpusets: randomize node rotor used in cpuset_mem_spread_node()
Some workloads that create a large number of small files tend to assign
too many pages to node 0 (multi-node systems).  Part of the reason is that
the rotor (in cpuset_mem_spread_node()) used to assign nodes starts at
node 0 for newly created tasks.

This patch changes the rotor to be initialized to a random node number of
the cpuset.

[akpm@linux-foundation.org: fix layout]
[Lee.Schermerhorn@hp.com: Define stub numa_random() for !NUMA configuration]
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Paul Menage <menage@google.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:44 -07:00
Jack Steiner 6adef3ebe5 cpusets: new round-robin rotor for SLAB allocations
We have observed several workloads running on multi-node systems where
memory is assigned unevenly across the nodes in the system.  There are
numerous reasons for this but one is the round-robin rotor in
cpuset_mem_spread_node().

For example, a simple test that writes a multi-page file will allocate
pages on nodes 0 2 4 6 ...  Odd nodes are skipped.  (Sometimes it
allocates on odd nodes & skips even nodes).

An example is shown below.  The program "lfile" writes a file consisting
of 10 pages.  The program then mmaps the file & uses get_mempolicy(...,
MPOL_F_NODE) to determine the nodes where the file pages were allocated.
The output is shown below:

	# ./lfile
	 allocated on nodes: 2 4 6 0 1 2 6 0 2

There is a single rotor that is used for allocating both file pages & slab
pages.  Writing the file allocates both a data page & a slab page
(buffer_head).  This advances the RR rotor 2 nodes for each page
allocated.

A quick confirmation seems to confirm this is the cause of the uneven
allocation:

	# echo 0 >/dev/cpuset/memory_spread_slab
	# ./lfile
	 allocated on nodes: 6 7 8 9 0 1 2 3 4 5

This patch introduces a second rotor that is used for slab allocations.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Paul Menage <menage@google.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:44 -07:00
Kirill A. Shutemov 907860ed38 cgroups: make cftype.unregister_event() void-returning
Since we are unable to handle an error returned by
cftype.unregister_event() properly, let's make the callback
void-returning.

mem_cgroup_unregister_event() has been rewritten to be a "never fail"
function.  On mem_cgroup_usage_register_event() we save old buffer for
thresholds array and reuse it in mem_cgroup_usage_unregister_event() to
avoid allocation.

Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Phil Carmody <ext-phil.2.carmody@nokia.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:44 -07:00
akpm@linux-foundation.org ac39cf8cb8 memcg: fix mis-accounting of file mapped racy with migration
FILE_MAPPED per memcg of migrated file cache is not properly updated,
because our hook in page_add_file_rmap() can't know to which memcg
FILE_MAPPED should be counted.

Basically, this patch is for fixing the bug but includes some big changes
to fix up other messes.

Now, at migrating mapped file, events happen in following sequence.

 1. allocate a new page.
 2. get memcg of an old page.
 3. charge ageinst a new page before migration. But at this point,
    no changes to new page's page_cgroup, no commit for the charge.
    (IOW, PCG_USED bit is not set.)
 4. page migration replaces radix-tree, old-page and new-page.
 5. page migration remaps the new page if the old page was mapped.
 6. Here, the new page is unlocked.
 7. memcg commits the charge for newpage, Mark the new page's page_cgroup
    as PCG_USED.

Because "commit" happens after page-remap, we can count FILE_MAPPED
at "5", because we should avoid to trust page_cgroup->mem_cgroup.
if PCG_USED bit is unset.
(Note: memcg's LRU removal code does that but LRU-isolation logic is used
 for helping it. When we overwrite page_cgroup->mem_cgroup, page_cgroup is
 not on LRU or page_cgroup->mem_cgroup is NULL.)

We can lose file_mapped accounting information at 5 because FILE_MAPPED
is updated only when mapcount changes 0->1. So we should catch it.

BTW, historically, above implemntation comes from migration-failure
of anonymous page. Because we charge both of old page and new page
with mapcount=0, we can't catch
  - the page is really freed before remap.
  - migration fails but it's freed before remap
or .....corner cases.

New migration sequence with memcg is:

 1. allocate a new page.
 2. mark PageCgroupMigration to the old page.
 3. charge against a new page onto the old page's memcg. (here, new page's pc
    is marked as PageCgroupUsed.)
 4. page migration replaces radix-tree, page table, etc...
 5. At remapping, new page's page_cgroup is now makrked as "USED"
    We can catch 0->1 event and FILE_MAPPED will be properly updated.

    And we can catch SWAPOUT event after unlock this and freeing this
    page by unmap() can be caught.

 7. Clear PageCgroupMigration of the old page.

So, FILE_MAPPED will be correctly updated.

Then, for what MIGRATION flag is ?
  Without it, at migration failure, we may have to charge old page again
  because it may be fully unmapped. "charge" means that we have to dive into
  memory reclaim or something complated. So, it's better to avoid
  charge it again. Before this patch, __commit_charge() was working for
  both of the old/new page and fixed up all. But this technique has some
  racy condtion around FILE_MAPPED and SWAPOUT etc...
  Now, the kernel use MIGRATION flag and don't uncharge old page until
  the end of migration.

I hope this change will make memcg's page migration much simpler.  This
page migration has caused several troubles.  Worth to add a flag for
simplification.

Reviewed-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Tested-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Reported-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:44 -07:00
Daisuke Nishimura 87946a7228 memcg: move charge of file pages
This patch adds support for moving charge of file pages, which include
normal file, tmpfs file and swaps of tmpfs file.  It's enabled by setting
bit 1 of <target cgroup>/memory.move_charge_at_immigrate.

Unlike the case of anonymous pages, file pages(and swaps) in the range
mmapped by the task will be moved even if the task hasn't done page fault,
i.e.  they might not be the task's "RSS", but other task's "RSS" that maps
the same file.  And mapcount of the page is ignored(the page can be moved
even if page_mapcount(page) > 1).  So, conditions that the page/swap
should be met to be moved is that it must be in the range mmapped by the
target task and it must be charged to the old cgroup.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix warning]
Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.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>
2010-05-27 09:12:43 -07:00
Felipe Balbi c4b5be98fe gpiolib: introduce set_debounce method
A few architectures, like OMAP, allow you to set a debouncing time for the
gpio before generating the IRQ.  Teach gpiolib about that.

Mark said:
: This would be generally useful for embedded systems, especially where
: the interrupt concerned is a wake source.  It allows drivers to avoid
: spurious interrupts from noisy sources so if the hardware supports it
: the driver can avoid having to explicitly wait for the signal to become
: stable and software has to cope with fewer events.  We've lived without
: it for quite some time, though.

David said:
: I looked at adding debounce support to the generic GPIO calls (and thus
: gpiolib) some time back, but decided against it.  I forget why at this
: time (check list archives) but it wasn't because of lack of utility in
: certain contexts.
:
: One thing to watch out for is just how variable the hardware capabilities
: are.  Atmel GPIOs have something like a fixed number of 32K clock cycles
: for debounce, twl4030 had something odd, OMAPs were more like the Atmel
: chips but with a different clock.  In some cases debouncing had to be
: ganged, not per-GPIO.  And so forth.

Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: David Brownell <david-b@pacbell.net>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:42 -07:00