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23489 commits

Author SHA1 Message Date
Michal Simek
3dece370ec mm: System without MMU do not need pte_mkwrite
The patch "thp: export maybe_mkwrite" (commit 14fd403f21) breaks
systems without MMU.

Error log:

    CC      arch/microblaze/mm/init.o
  In file included from include/linux/mman.h:14,
                   from arch/microblaze/mm/consistent.c:24:
  include/linux/mm.h: In function 'maybe_mkwrite':
  include/linux/mm.h:482: error: implicit declaration of function 'pte_mkwrite'
  include/linux/mm.h:482: error: incompatible types in assignment

Signed-off-by: Michal Simek <monstr@monstr.eu>
CC: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-21 08:40:30 -08:00
John Stultz
aa0be0f465 RTC: Propagate error handling via rtc_timer_enqueue properly
In cases where RTC hardware does not support alarms, the virtualized
RTC interfaces did not have a way to propagate the error up to userland.

This patch extends rtc_timer_enqueue so it catches errors from the hardware
and returns them upwards to the virtualized interfaces. To simplify error
handling, it also internalizes the management of the timer->enabled bit
into rtc_timer_enqueue and rtc_timer_remove.

Also makes rtc_timer_enqueue and rtc_timer_remove static.

Reported-by: David Daney <ddaney@caviumnetworks.com>
Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Diagnosed-by: David Daney <ddaney@caviumnetworks.com>
Tested-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
LKML-Reference: <1295565973-14358-1-git-send-email-john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-21 17:38:19 +01:00
John Stultz
1daeddd596 rtc: Cleanup removed UIE emulation declaration
rtc_dev_update_irq_enable_emul was removed in commit
042620a018 (UIE emulation is
now handled via hrtimer), but the declaration was missed.
This patch cleans it up.

Signed-off-by: John Stultz <john.stultz@linaro.org>
LKML-Reference: <1294939849-20608-1-git-send-email-john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-21 17:38:18 +01:00
Linus Torvalds
4843456c5c Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
  quota: Fix deadlock during path resolution
2011-01-21 07:33:37 -08:00
Thomas Gleixner
1c77ff22f5 genirq: Remove __do_IRQ
All architectures are finally converted. Remove the cruft.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Michal Simek <monstr@monstr.eu>
Acked-by: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
2011-01-21 11:55:31 +01:00
Linus Torvalds
2b1caf6ed7 Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  smp: Allow on_each_cpu() to be called while early_boot_irqs_disabled status to init/main.c
  lockdep: Move early boot local IRQ enable/disable status to init/main.c
2011-01-20 18:30:37 -08:00
Rafael J. Wysocki
2d6d9fd3a5 ACPI: Introduce acpi_os_ioremap()
Commit ca9b600be3 ("ACPI / PM: Make suspend_nvs_save() use
acpi_os_map_memory()") attempted to prevent the code in osl.c and nvs.c
from using different ioremap() variants by making the latter use
acpi_os_map_memory() for mapping the NVS pages.  However, that also
requires acpi_os_unmap_memory() to be used for unmapping them, which
causes synchronize_rcu() to be executed many times in a row
unnecessarily and introduces substantial delays during resume on some
systems.

Instead of using acpi_os_map_memory() for mapping the NVS pages in nvs.c
introduce acpi_os_ioremap() calling ioremap_cache() and make the code in
both osl.c and nvs.c use it.

Reported-by: Jeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-20 18:30:17 -08:00
KAMEZAWA Hiroyuki
ca3e021417 memcg: fix USED bit handling at uncharge in THP
Now, under THP:

at charge:
  - PageCgroupUsed bit is set to all page_cgroup on a hugepage.
    ....set to 512 pages.
at uncharge
  - PageCgroupUsed bit is unset on the head page.

So, some pages will remain with "Used" bit.

This patch fixes that Used bit is set only to the head page.
Used bits for tail pages will be set at splitting if necessary.

This patch adds this lock order:
   compound_lock() -> page_cgroup_move_lock().

[akpm@linux-foundation.org: fix warning]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-20 17:02:06 -08:00
Tejun Heo
2ce802f62b lockdep: Move early boot local IRQ enable/disable status to init/main.c
During early boot, local IRQ is disabled until IRQ subsystem is
properly initialized.  During this time, no one should enable
local IRQ and some operations which usually are not allowed with
IRQ disabled, e.g. operations which might sleep or require
communications with other processors, are allowed.

lockdep tracked this with early_boot_irqs_off/on() callbacks.
As other subsystems need this information too, move it to
init/main.c and make it generally available.  While at it,
toggle the boolean to early_boot_irqs_disabled instead of
enabled so that it can be initialized with %false and %true
indicates the exceptional condition.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <20110120110635.GB6036@htj.dyndns.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-20 13:32:33 +01:00
Linus Torvalds
1268afe676 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (41 commits)
  sctp: user perfect name for Delayed SACK Timer option
  net: fix can_checksum_protocol() arguments swap
  Revert "netlink: test for all flags of the NLM_F_DUMP composite"
  gianfar: Fix misleading indentation in startup_gfar()
  net/irda/sh_irda: return to RX mode when TX error
  net offloading: Do not mask out NETIF_F_HW_VLAN_TX for vlan.
  USB CDC NCM: tx_fixup() race condition fix
  ns83820: Avoid bad pointer deref in ns83820_init_one().
  ipv6: Silence privacy extensions initialization
  bnx2x: Update bnx2x version to 1.62.00-4
  bnx2x: Fix AER setting for BCM57712
  bnx2x: Fix BCM84823 LED behavior
  bnx2x: Mark full duplex on some external PHYs
  bnx2x: Fix BCM8073/BCM8727 microcode loading
  bnx2x: LED fix for BCM8727 over BCM57712
  bnx2x: Common init will be executed only once after POR
  bnx2x: Swap BCM8073 PHY polarity if required
  iwlwifi: fix valid chain reading from EEPROM
  ath5k: fix locking in tx_complete_poll_work
  ath9k_hw: do PA offset calibration only on longcal interval
  ...
2011-01-19 20:25:45 -08:00
David S. Miller
f966a13f92 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-2.6 2011-01-18 12:50:19 -08:00
Naveen Kumar Gaddipati
d2763b4f44 Input: bu21013_ts - remove duplicate resolution parameters
Remove duplicate display resolution parameters from platform data as
one pair is quite enough.

Signed-off-by: Naveen Kumar Gaddipati <naveen.gaddipati@stericsson.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-01-17 20:49:12 -08:00
Linus Torvalds
6845a44a31 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
  RDMA: Update workqueue usage
  RDMA/nes: Fix incorrect SFP+ link status detection on driver init
  RDMA/nes: Fix SFP+ link down detection issue with switch port disable
  RDMA/nes: Generate IB_EVENT_PORT_ERR/PORT_ACTIVE events
  RDMA/nes: Fix bonding on iw_nes
  IB/srp: Test only once whether iu allocation succeeded
  IB/mlx4: Handle protocol field in multicast table
  RDMA: Use vzalloc() to replace vmalloc()+memset(0)
  mlx4_{core, ib, en}: Fix driver when sizeof (phys_addr_t) > sizeof (long)
  IB/mthca: Fix driver when sizeof (phys_addr_t) > sizeof (long)
2011-01-17 14:45:48 -08:00
Linus Torvalds
9e8a462a01 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ecryptfs/ecryptfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ecryptfs/ecryptfs-2.6:
  ecryptfs: remove unnecessary decrypt when extending a file
  ecryptfs: Fix ecryptfs_printk() size_t warnings
  fs/ecryptfs: Add printf format/argument verification and fix fallout
  ecryptfs: fixed testing of file descriptor flags
  ecryptfs: test lower_file pointer when lower_file_mutex is locked
  ecryptfs: missing initialization of the superblock 'magic' field
  ecryptfs: moved ECRYPTFS_SUPER_MAGIC definition to linux/magic.h
  ecryptfs: fix truncation error in ecryptfs_read_update_atime
2011-01-17 12:39:57 -08:00
Linus Torvalds
8c34482c17 Merge branch 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6
* 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6:
  spi/spi_sh_msiof: fix a wrong free_irq() parameter
  dt/flattree: Return virtual address from early_init_dt_alloc_memory_arch()
2011-01-17 11:18:40 -08:00
Linus Torvalds
ab2020f2f1 Merge git://git.infradead.org/mtd-2.6
* git://git.infradead.org/mtd-2.6: (59 commits)
  mtd: mtdpart: disallow reading OOB past the end of the partition
  mtd: pxa3xx_nand: NULL dereference in pxa3xx_nand_probe
  UBI: use mtd->writebufsize to set minimal I/O unit size
  mtd: initialize writebufsize in the MTD object of a partition
  mtd: onenand: add mtd->writebufsize initialization
  mtd: nand: add mtd->writebufsize initialization
  mtd: cfi: add writebufsize initialization
  mtd: add writebufsize field to mtd_info struct
  mtd: OneNAND: OMAP2/3: prevent regulator sleeping while OneNAND is in use
  mtd: OneNAND: add enable / disable methods to onenand_chip
  mtd: m25p80: Fix JEDEC ID for AT26DF321
  mtd: txx9ndfmc: limit transfer bytes to 512 (ECC provides 6 bytes max)
  mtd: cfi_cmdset_0002: add support for Samsung K8D3x16UxC NOR chips
  mtd: cfi_cmdset_0002: add support for Samsung K8D6x16UxM NOR chips
  mtd: nand: ams-delta: drop omap_read/write, use ioremap
  mtd: m25p80: add debugging trace in sst_write
  mtd: nand: ams-delta: select for built-in by default
  mtd: OneNAND: lighten scary initial bad block messages
  mtd: OneNAND: OMAP2/3: add support for command line partitioning
  mtd: nand: rearrange ONFI revision checking, add ONFI 2.3
  ...

Fix up trivial conflict in drivers/mtd/Kconfig as per DavidW.
2011-01-17 11:15:30 -08:00
Linus Torvalds
235646a486 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  fs: fix address space warnings in ioctl_fiemap()
  aio: check return value of create_workqueue()
  hpfs_setattr error case avoids unlock_kernel
  compat: copy missing fields in compat_statfs64 to user
  compat: update comment of compat statfs syscalls
  compat: remove unnecessary assignment in compat_rw_copy_check_uvector()
  fs: FS_POSIX_ACL does not depend on BLOCK
  fs: Remove unlikely() from fget_light()
  fs: Remove unlikely() from fput_light()
  fallocate should be a file operation
  make the feature checks in ->fallocate future proof
  staging: smbfs building fix
  tidy up around finish_automount()
  don't drop newmnt on error in do_add_mount()
  Take the completion of automount into new helper
2011-01-17 11:00:09 -08:00
Linus Torvalds
e1288cd72f Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (63 commits)
  ARM: PL08x: cleanup comments
  Update CONFIG_MD_RAID6_PQ to CONFIG_RAID6_PQ in drivers/dma/iop-adma.c
  ARM: PL08x: fix a warning
  Fix dmaengine_submit() return type
  dmaengine: at_hdmac: fix race while monitoring channel status
  dmaengine: at_hdmac: flags located in first descriptor
  dmaengine: at_hdmac: use subsys_initcall instead of module_init
  dmaengine: at_hdmac: no need set ACK in new descriptor
  dmaengine: at_hdmac: trivial add precision to unmapping comment
  dmaengine: at_hdmac: use dma_address to program DMA hardware
  pch_dma: support new device ML7213 IOH
  ARM: PL08x: prevent dma_set_runtime_config() reconfiguring memcpy channels
  ARM: PL08x: allow dma_set_runtime_config() to return errors
  ARM: PL08x: fix locking between prepare function and submit function
  ARM: PL08x: introduce 'phychan_hold' to hold on to physical channels
  ARM: PL08x: put txd's on the pending list in pl08x_tx_submit()
  ARM: PL08x: rename 'desc_list' as 'pend_list'
  ARM: PL08x: implement unmapping of memcpy buffers
  ARM: PL08x: store prep_* flags in async_tx structure
  ARM: PL08x: shrink srcbus/dstbus in txd structure
  ...
2011-01-17 10:54:41 -08:00
Roberto Sassu
2a8652f4e0 ecryptfs: moved ECRYPTFS_SUPER_MAGIC definition to linux/magic.h
The definition of ECRYPTFS_SUPER_MAGIC has been moved to the include
file 'linux/magic.h' to become available to other kernel subsystems.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-01-17 10:44:31 -06:00
Namhyung Kim
ecf5632dd1 fs: fix address space warnings in ioctl_fiemap()
The fi_extents_start field of struct fiemap_extent_info is a
user pointer but was not marked as __user. This makes sparse
emit following warnings:

  CHECK   fs/ioctl.c
fs/ioctl.c:114:26: warning: incorrect type in argument 1 (different address spaces)
fs/ioctl.c:114:26:    expected void [noderef] <asn:1>*dst
fs/ioctl.c:114:26:    got struct fiemap_extent *[assigned] dest
fs/ioctl.c:202:14: warning: incorrect type in argument 1 (different address spaces)
fs/ioctl.c:202:14:    expected void const volatile [noderef] <asn:1>*<noident>
fs/ioctl.c:202:14:    got struct fiemap_extent *[assigned] fi_extents_start
fs/ioctl.c:212:27: warning: incorrect type in argument 1 (different address spaces)
fs/ioctl.c:212:27:    expected void [noderef] <asn:1>*dst
fs/ioctl.c:212:27:    got char *<noident>

Also add 'ufiemap' variable to eliminate unnecessary casts.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-17 08:21:42 -05:00
Steven Rostedt
c2b3e74b78 fs: Remove unlikely() from fput_light()
In fput_light(), there's an unlikely(fput_needed), which running on
my normal desktop doing firefox, xchat, evolution and part of my distcc farm,
and running the annotate branch profiler shows that the unlikely is not
very unlikely.

 correct incorrect  %        Function             File              Line
 ------- ---------  -        --------             ----              ----
       0       48 100 fput_light                file.h               26
115828710 897415279  88 fput_light              file.h               26
865271179 5286128445  85 fput_light             file.h               26
19568539  8923664  31 fput_light                file.h               26
12353677  3562279  22 fput_light                file.h               26
  267691    67062  20 fput_light                file.h               26
15014853   348172   2 fput_light                file.h               26
  209258      205   0 fput_light                file.h               26
 1364164        0   0 fput_light                file.h               26

Which gives 1032903812 times it was correct and 6203351846 times it was
incorrect, or 85% incorrect.

Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-17 03:26:26 -05:00
Christoph Hellwig
2fe17c1075 fallocate should be a file operation
Currently all filesystems except XFS implement fallocate asynchronously,
while XFS forced a commit.  Both of these are suboptimal - in case of O_SYNC
I/O we really want our allocation on disk, especially for the !KEEP_SIZE
case where we actually grow the file with user-visible zeroes.  On the
other hand always commiting the transaction is a bad idea for fast-path
uses of fallocate like for example in recent Samba versions.   Given
that block allocation is a data plane operation anyway change it from
an inode operation to a file operation so that we have the file structure
available that lets us check for O_SYNC.

This also includes moving the code around for a few of the filesystems,
and remove the already unnedded S_ISDIR checks given that we only wire
up fallocate for regular files.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-17 02:25:31 -05:00
Russell King - ARM Linux
94ae85220a ARM: PL08x: cleanup comments
Cleanup the formatting of comments, remove some which don't make sense
anymore.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[fix conflict with 96a608a4]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-16 16:55:43 -08:00
Rafael J. Wysocki
fc8fe1e992 PCI / ACPI: Fix build of the AER driver for CONFIG_ACPI unset
After commit 415e12b237 ("PCI/ACPI: Request _OSC control once for each
root bridge (v3)") include/linux/pci-acpi.h is included by
drivers/pci/pcie/aer/aerdrv.c and if CONFIG_ACPI is unset, the bogus and
unnecessary alternative definition of acpi_find_root_bridge_handle()
causes a build error to occur.

Remove the offending piece of garbage.

Reported-and-tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-16 11:56:26 -08:00
Linus Torvalds
f8206b925f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (23 commits)
  sanitize vfsmount refcounting changes
  fix old umount_tree() breakage
  autofs4: Merge the remaining dentry ops tables
  Unexport do_add_mount() and add in follow_automount(), not ->d_automount()
  Allow d_manage() to be used in RCU-walk mode
  Remove a further kludge from __do_follow_link()
  autofs4: Bump version
  autofs4: Add v4 pseudo direct mount support
  autofs4: Fix wait validation
  autofs4: Clean up autofs4_free_ino()
  autofs4: Clean up dentry operations
  autofs4: Clean up inode operations
  autofs4: Remove unused code
  autofs4: Add d_manage() dentry operation
  autofs4: Add d_automount() dentry operation
  Remove the automount through follow_link() kludge code from pathwalk
  CIFS: Use d_automount() rather than abusing follow_link()
  NFS: Use d_automount() rather than abusing follow_link()
  AFS: Use d_automount() rather than abusing follow_link()
  Add an AT_NO_AUTOMOUNT flag to suppress terminal automount
  ...
2011-01-16 11:31:50 -08:00
Al Viro
f03c65993b sanitize vfsmount refcounting changes
Instead of splitting refcount between (per-cpu) mnt_count
and (SMP-only) mnt_longrefs, make all references contribute
to mnt_count again and keep track of how many are longterm
ones.

Accounting rules for longterm count:
	* 1 for each fs_struct.root.mnt
	* 1 for each fs_struct.pwd.mnt
	* 1 for having non-NULL ->mnt_ns
	* decrement to 0 happens only under vfsmount lock exclusive

That allows nice common case for mntput() - since we can't drop the
final reference until after mnt_longterm has reached 0 due to the rules
above, mntput() can grab vfsmount lock shared and check mnt_longterm.
If it turns out to be non-zero (which is the common case), we know
that this is not the final mntput() and can just blindly decrement
percpu mnt_count.  Otherwise we grab vfsmount lock exclusive and
do usual decrement-and-check of percpu mnt_count.

For fs_struct.c we have mnt_make_longterm() and mnt_make_shortterm();
namespace.c uses the latter in places where we don't already hold
vfsmount lock exclusive and opencodes a few remaining spots where
we need to manipulate mnt_longterm.

Note that we mostly revert the code outside of fs/namespace.c back
to what we used to have; in particular, normal code doesn't need
to care about two kinds of references, etc.  And we get to keep
the optimization Nick's variant had bought us...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-16 13:47:07 -05:00
Grant Likely
672c54466d dt/flattree: Return virtual address from early_init_dt_alloc_memory_arch()
The physical address is never used by the device tree code when
allocating memory for unflattening.  Change the architecture's alloc
hook to return the virutal address instead.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-01-15 22:01:58 -07:00
David Howells
ea5b778a8b Unexport do_add_mount() and add in follow_automount(), not ->d_automount()
Unexport do_add_mount() and make ->d_automount() return the vfsmount to be
added rather than calling do_add_mount() itself.  follow_automount() will then
do the addition.

This slightly complicates things as ->d_automount() normally wants to add the
new vfsmount to an expiration list and start an expiration timer.  The problem
with that is that the vfsmount will be deleted if it has a refcount of 1 and
the timer will not repeat if the expiration list is empty.

To this end, we require the vfsmount to be returned from d_automount() with a
refcount of (at least) 2.  One of these refs will be dropped unconditionally.
In addition, follow_automount() must get a 3rd ref around the call to
do_add_mount() lest it eat a ref and return an error, leaving the mount we
have open to being expired as we would otherwise have only 1 ref on it.

d_automount() should also add the the vfsmount to the expiration list (by
calling mnt_set_expiry()) and start the expiration timer before returning, if
this mechanism is to be used.  The vfsmount will be unlinked from the
expiration list by follow_automount() if do_add_mount() fails.

This patch also fixes the call to do_add_mount() for AFS to propagate the mount
flags from the parent vfsmount.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15 20:07:48 -05:00
David Howells
ab90911ff9 Allow d_manage() to be used in RCU-walk mode
Allow d_manage() to be called from pathwalk when it is in RCU-walk mode as well
as when it is in Ref-walk mode.  This permits __follow_mount_rcu() to call
d_manage() directly.  d_manage() needs a parameter to indicate that it is in
RCU-walk mode as it isn't allowed to sleep if in that mode (but should return
-ECHILD instead).

autofs4_d_manage() can then be set to retain RCU-walk mode if the daemon
accesses it and otherwise request dropping back to ref-walk mode.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15 20:07:47 -05:00
Ian Kent
1972580bb4 autofs4: Bump version
Increase the autofs module sub-version so we can tell what kernel
implementation is being used from user space debug logging.

Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15 20:07:45 -05:00
David Howells
36d43a4376 NFS: Use d_automount() rather than abusing follow_link()
Make NFS use the new d_automount() dentry operation rather than abusing
follow_link() on directories.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15 20:07:34 -05:00
David Howells
6f45b65672 Add an AT_NO_AUTOMOUNT flag to suppress terminal automount
Add an AT_NO_AUTOMOUNT flag to suppress terminal automounting of automount
point directories.  This can be used by fstatat() users to permit the
gathering of attributes on an automount point and also prevent
mass-automounting of a directory of automount points by ls.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15 20:07:33 -05:00
David Howells
cc53ce53c8 Add a dentry op to allow processes to be held during pathwalk transit
Add a dentry op (d_manage) to permit a filesystem to hold a process and make it
sleep when it tries to transit away from one of that filesystem's directories
during a pathwalk.  The operation is keyed off a new dentry flag
(DCACHE_MANAGE_TRANSIT).

The filesystem is allowed to be selective about which processes it holds and
which it permits to continue on or prohibits from transiting from each flagged
directory.  This will allow autofs to hold up client processes whilst letting
its userspace daemon through to maintain the directory or the stuff behind it
or mounted upon it.

The ->d_manage() dentry operation:

	int (*d_manage)(struct path *path, bool mounting_here);

takes a pointer to the directory about to be transited away from and a flag
indicating whether the transit is undertaken by do_add_mount() or
do_move_mount() skipping through a pile of filesystems mounted on a mountpoint.

It should return 0 if successful and to let the process continue on its way;
-EISDIR to prohibit the caller from skipping to overmounted filesystems or
automounting, and to use this directory; or some other error code to return to
the user.

->d_manage() is called with namespace_sem writelocked if mounting_here is true
and no other locks held, so it may sleep.  However, if mounting_here is true,
it may not initiate or wait for a mount or unmount upon the parameter
directory, even if the act is actually performed by userspace.

Within fs/namei.c, follow_managed() is extended to check with d_manage() first
on each managed directory, before transiting away from it or attempting to
automount upon it.

follow_down() is renamed follow_down_one() and should only be used where the
filesystem deliberately intends to avoid management steps (e.g. autofs).

A new follow_down() is added that incorporates the loop done by all other
callers of follow_down() (do_add/move_mount(), autofs and NFSD; whilst AFS, NFS
and CIFS do use it, their use is removed by converting them to use
d_automount()).  The new follow_down() calls d_manage() as appropriate.  It
also takes an extra parameter to indicate if it is being called from mount code
(with namespace_sem writelocked) which it passes to d_manage().  follow_down()
ignores automount points so that it can be used to mount on them.

__follow_mount_rcu() is made to abort rcu-walk mode if it hits a directory with
DCACHE_MANAGE_TRANSIT set on the basis that we're probably going to have to
sleep.  It would be possible to enter d_manage() in rcu-walk mode too, and have
that determine whether to abort or not itself.  That would allow the autofs
daemon to continue on in rcu-walk mode.

Note that DCACHE_MANAGE_TRANSIT on a directory should be cleared when it isn't
required as every tranist from that directory will cause d_manage() to be
invoked.  It can always be set again when necessary.

==========================
WHAT THIS MEANS FOR AUTOFS
==========================

Autofs currently uses the lookup() inode op and the d_revalidate() dentry op to
trigger the automounting of indirect mounts, and both of these can be called
with i_mutex held.

autofs knows that the i_mutex will be held by the caller in lookup(), and so
can drop it before invoking the daemon - but this isn't so for d_revalidate(),
since the lock is only held on _some_ of the code paths that call it.  This
means that autofs can't risk dropping i_mutex from its d_revalidate() function
before it calls the daemon.

The bug could manifest itself as, for example, a process that's trying to
validate an automount dentry that gets made to wait because that dentry is
expired and needs cleaning up:

	mkdir         S ffffffff8014e05a     0 32580  24956
	Call Trace:
	 [<ffffffff885371fd>] :autofs4:autofs4_wait+0x674/0x897
	 [<ffffffff80127f7d>] avc_has_perm+0x46/0x58
	 [<ffffffff8009fdcf>] autoremove_wake_function+0x0/0x2e
	 [<ffffffff88537be6>] :autofs4:autofs4_expire_wait+0x41/0x6b
	 [<ffffffff88535cfc>] :autofs4:autofs4_revalidate+0x91/0x149
	 [<ffffffff80036d96>] __lookup_hash+0xa0/0x12f
	 [<ffffffff80057a2f>] lookup_create+0x46/0x80
	 [<ffffffff800e6e31>] sys_mkdirat+0x56/0xe4

versus the automount daemon which wants to remove that dentry, but can't
because the normal process is holding the i_mutex lock:

	automount     D ffffffff8014e05a     0 32581      1              32561
	Call Trace:
	 [<ffffffff80063c3f>] __mutex_lock_slowpath+0x60/0x9b
	 [<ffffffff8000ccf1>] do_path_lookup+0x2ca/0x2f1
	 [<ffffffff80063c89>] .text.lock.mutex+0xf/0x14
	 [<ffffffff800e6d55>] do_rmdir+0x77/0xde
	 [<ffffffff8005d229>] tracesys+0x71/0xe0
	 [<ffffffff8005d28d>] tracesys+0xd5/0xe0

which means that the system is deadlocked.

This patch allows autofs to hold up normal processes whilst the daemon goes
ahead and does things to the dentry tree behind the automouter point without
risking a deadlock as almost no locks are held in d_manage() and none in
d_automount().

Signed-off-by: David Howells <dhowells@redhat.com>
Was-Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15 20:07:31 -05:00
David Howells
9875cf8064 Add a dentry op to handle automounting rather than abusing follow_link()
Add a dentry op (d_automount) to handle automounting directories rather than
abusing the follow_link() inode operation.  The operation is keyed off a new
dentry flag (DCACHE_NEED_AUTOMOUNT).

This also makes it easier to add an AT_ flag to suppress terminal segment
automount during pathwalk and removes the need for the kludge code in the
pathwalk algorithm to handle directories with follow_link() semantics.

The ->d_automount() dentry operation:

	struct vfsmount *(*d_automount)(struct path *mountpoint);

takes a pointer to the directory to be mounted upon, which is expected to
provide sufficient data to determine what should be mounted.  If successful, it
should return the vfsmount struct it creates (which it should also have added
to the namespace using do_add_mount() or similar).  If there's a collision with
another automount attempt, NULL should be returned.  If the directory specified
by the parameter should be used directly rather than being mounted upon,
-EISDIR should be returned.  In any other case, an error code should be
returned.

The ->d_automount() operation is called with no locks held and may sleep.  At
this point the pathwalk algorithm will be in ref-walk mode.

Within fs/namei.c itself, a new pathwalk subroutine (follow_automount()) is
added to handle mountpoints.  It will return -EREMOTE if the automount flag was
set, but no d_automount() op was supplied, -ELOOP if we've encountered too many
symlinks or mountpoints, -EISDIR if the walk point should be used without
mounting and 0 if successful.  The path will be updated to point to the mounted
filesystem if a successful automount took place.

__follow_mount() is replaced by follow_managed() which is more generic
(especially with the patch that adds ->d_manage()).  This handles transits from
directories during pathwalk, including automounting and skipping over
mountpoints (and holding processes with the next patch).

__follow_mount_rcu() will jump out of RCU-walk mode if it encounters an
automount point with nothing mounted on it.

follow_dotdot*() does not handle automounts as you don't want to trigger them
whilst following "..".

I've also extracted the mount/don't-mount logic from autofs4 and included it
here.  It makes the mount go ahead anyway if someone calls open() or creat(),
tries to traverse the directory, tries to chdir/chroot/etc. into the directory,
or sticks a '/' on the end of the pathname.  If they do a stat(), however,
they'll only trigger the automount if they didn't also say O_NOFOLLOW.

I've also added an inode flag (S_AUTOMOUNT) so that filesystems can mark their
inodes as automount points.  This flag is automatically propagated to the
dentry as DCACHE_NEED_AUTOMOUNT by __d_instantiate().  This saves NFS and could
save AFS a private flag bit apiece, but is not strictly necessary.  It would be
preferable to do the propagation in d_set_d_op(), but that doesn't normally
have access to the inode.

[AV: fixed breakage in case if __follow_mount_rcu() fails and nameidata_drop_rcu()
succeeds in RCU case of do_lookup(); we need to fall through to non-RCU case after
that, rather than just returning with ungrabbed *path]

Signed-off-by: David Howells <dhowells@redhat.com>
Was-Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15 20:05:03 -05:00
Pekka Enberg
597fb188cb Merge branch 'slub/hotplug' into slab/urgent 2011-01-15 13:28:17 +02:00
Dan Williams
96a608a4bf ARM: PL08x: fix a warning
drivers/dma/amba-pl08x.c: In function 'pl08x_start_txd':
drivers/dma/amba-pl08x.c:205: warning: dereferencing 'void *' pointer

We never dereference llis_va aside from assigning it to a struct
pl08x_lli pointer or calculating the address of array element 0.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-14 17:51:11 -08:00
Russell King - ARM Linux
98d530fe24 Fix dmaengine_submit() return type
desc->tx_submit's return type is dma_cookie_t, not int.  Therefore,
dmaengine_submit() should match this return type as it's just
wrapping this detail.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-14 17:07:49 -08:00
Andiry Xu
0029227f1b xHCI: synchronize irq in xhci_suspend()
Synchronize the interrupts instead of free them in xhci_suspend(). This will
prevent a double free when the host is suspended and then the card removed.

Set the flag hcd->msix_enabled when using MSI-X, and check the flag in
suspend_common(). MSI-X synchronization will be handled by xhci_suspend(),
and MSI/INTx will be synchronized in suspend_common().

This patch should be queued for the 2.6.37 stable tree.

Reported-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org
2011-01-14 15:28:52 -08:00
Markus Trippelsdorf
ab0724ffee PCI / ACPI: Fix build issue in pci_root.c for !CONFIG_PCIEPORTBUS
The compilation of drivers/acpi/pci_root.c fails if
CONFIG_PCIEPORTBUS is unset.  Fix the problem.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-14 15:23:25 -08:00
Linus Torvalds
6ab8219649 Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  block: restore multiple bd_link_disk_holder() support
  block cfq: compensate preempted queue even if it has no slice assigned
  block cfq: make queue preempt work for queues from different workload
2011-01-14 13:32:07 -08:00
Linus Torvalds
d018b6f4f1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (47 commits)
  GRETH: resolve SMP issues and other problems
  GRETH: handle frame error interrupts
  GRETH: avoid writing bad speed/duplex when setting transfer mode
  GRETH: fixed skb buffer memory leak on frame errors
  GRETH: GBit transmit descriptor handling optimization
  GRETH: fix opening/closing
  GRETH: added raw AMBA vendor/device number to match against.
  cassini: Fix build bustage on x86.
  e1000e: consistent use of Rx/Tx vs. RX/TX/rx/tx in comments/logs
  e1000e: update Copyright for 2011
  e1000: Avoid unhandled IRQ
  r8169: keep firmware in memory.
  netdev: tilepro: Use is_unicast_ether_addr helper
  etherdevice.h: Add is_unicast_ether_addr function
  ks8695net: Use default implementation of ethtool_ops::get_link
  ks8695net: Disable non-working ethtool operations
  USB CDC NCM: Don't deref NULL in cdc_ncm_rx_fixup() and don't use uninitialized variable.
  vxge: Remember to release firmware after upgrading firmware
  netdev: bfin_mac: Remove is_multicast_ether_addr use in netdev_for_each_mc_addr
  ipsec: update MAX_AH_AUTH_LEN to support sha512
  ...
2011-01-14 13:25:30 -08:00
Linus Torvalds
18bce371ae Merge branch 'for-2.6.38' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.38' of git://linux-nfs.org/~bfields/linux: (62 commits)
  nfsd4: fix callback restarting
  nfsd: break lease on unlink, link, and rename
  nfsd4: break lease on nfsd setattr
  nfsd: don't support msnfs export option
  nfsd4: initialize cb_per_client
  nfsd4: allow restarting callbacks
  nfsd4: simplify nfsd4_cb_prepare
  nfsd4: give out delegations more quickly in 4.1 case
  nfsd4: add helper function to run callbacks
  nfsd4: make sure sequence flags are set after destroy_session
  nfsd4: re-probe callback on connection loss
  nfsd4: set sequence flag when backchannel is down
  nfsd4: keep finer-grained callback status
  rpc: allow xprt_class->setup to return a preexisting xprt
  rpc: keep backchannel xprt as long as server connection
  rpc: move sk_bc_xprt to svc_xprt
  nfsd4: allow backchannel recovery
  nfsd4: support BIND_CONN_TO_SESSION
  nfsd4: modify session list under cl_lock
  Documentation: fl_mylease no longer exists
  ...

Fix up conflicts in fs/nfsd/vfs.c with the vfs-scale work.  The
vfs-scale work touched some msnfs cases, and this merge removes support
for that entirely, so the conflict was trivial to resolve.
2011-01-14 13:17:26 -08:00
Tejun Heo
49731baa41 block: restore multiple bd_link_disk_holder() support
Commit e09b457b (block: simplify holder symlink handling) incorrectly
assumed that there is only one link at maximum.  dm may use multiple
links and expects block layer to track reference count for each link,
which is different from and unrelated to the exclusive device holder
identified by @holder when the device is opened.

Remove the single holder assumption and automatic removal of the link
and revive the per-link reference count tracking.  The code
essentially behaves the same as before commit e09b457b sans the
unnecessary kobject reference count dancing.

While at it, note that this facility should not be used by anyone else
than the current ones.  Sysfs symlinks shouldn't be abused like this
and the whole thing doesn't belong in the block layer at all.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Milan Broz <mbroz@redhat.com>
Cc: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Neil Brown <neilb@suse.de>
Cc: linux-raid@vger.kernel.org
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-01-14 18:44:22 +01:00
Linus Torvalds
d73b388459 Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI/PM: Report wakeup events before resuming devices
  PCI/PM: Use pm_wakeup_event() directly for reporting wakeup events
  PCI: sysfs: Update ROM to include default owner write access
  x86/PCI: make Broadcom CNB20LE driver EMBEDDED and EXPERIMENTAL
  x86/PCI: don't use native Broadcom CNB20LE driver when ACPI is available
  PCI/ACPI: Request _OSC control once for each root bridge (v3)
  PCI: enable pci=bfsort by default on future Dell systems
  PCI/PCIe: Clear Root PME Status bits early during system resume
  PCI: pci-stub: ignore zero-length id parameters
  x86/PCI: irq and pci_ids patch for Intel Patsburg
  PCI: Skip id checking if no id is passed
  PCI: fix __pci_device_probe kernel-doc warning
  PCI: make pci_restore_state return void
  PCI: Disable ASPM if BIOS asks us to
  PCI: Add mask bit definition for MSI-X table
  PCI: MSI: Move MSI-X entry definition to pci_regs.h

Fix up trivial conflicts in drivers/net/{skge.c,sky2.c} that had in the
meantime been converted to not use legacy PCI power management, and thus
no longer use pci_restore_state() at all (and that caused trivial
conflicts with the "make pci_restore_state return void" patch)
2011-01-14 09:29:05 -08:00
Linus Torvalds
5957e33d6a Merge git://git.infradead.org/battery-2.6
* git://git.infradead.org/battery-2.6: (21 commits)
  power_supply: Add MAX17042 Fuel Gauge Driver
  olpc_battery: Fix up XO-1.5 properties list
  olpc_battery: Add support for CURRENT_NOW and VOLTAGE_NOW
  olpc_battery: Add support for CHARGE_NOW
  olpc_battery: Add support for CHARGE_FULL_DESIGN
  olpc_battery: Ambient temperature is not available on XO-1.5
  jz4740-battery: Should include linux/io.h
  s3c_adc_battery: Add gpio_inverted field to pdata
  power_supply: Don't use flush_scheduled_work()
  power_supply: Fix use after free and memory leak
  gpio-charger: Fix potential race between irq handler and probe/remove
  gpio-charger: Provide default name for the power_supply
  gpio-charger: Check result of kzalloc
  jz4740-battery: Check if platform_data is supplied
  isp1704_charger: Detect charger after probe
  isp1704_charger: Set isp->dev before anything needs it
  isp1704_charger: Detect HUB/Host chargers
  isp1704_charger: Correct length for storing model
  power_supply: Add gpio charger driver
  jz4740-battery: Protect against concurrent battery readings
  ...
2011-01-14 09:25:59 -08:00
Linus Torvalds
acda4721ae 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:
  kernel: fix hlist_bl again
  cgroups: Fix a lockdep warning at cgroup removal
  fs: namei fix ->put_link on wrong inode in do_filp_open
2011-01-14 09:08:29 -08:00
Linus Torvalds
822e5215f9 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6: (59 commits)
  mfd: ab8500-core chip version cut 2.0 support
  mfd: Flag WM831x /IRQ as a wake source
  mfd: Convert WM831x away from legacy I2C PM operations
  regulator: Support MAX8998/LP3974 DVS-GPIO
  mfd: Support LP3974 RTC
  i2c: Convert SCx200 driver from using raw PCI to platform device
  x86: OLPC: convert olpc-xo1 driver from pci device to platform device
  mfd: MAX8998/LP3974 hibernation support
  mfd/ab8500: remove spi support
  mfd: Remove ARCH_U8500 dependency from AB8500
  misc: Make AB8500_PWM driver depend on U8500 due to PWM breakage
  mfd: Add __devexit annotation for vx855_remove
  mfd: twl6030 irq_data conversion.
  gpio: Fix cs5535 printk warnings
  misc: Fix cs5535 printk warnings
  mfd: Convert Wolfson MFD drivers to use irq_data accessor function
  mfd: Convert TWL4030 to new irq_ APIs
  mfd: Convert tps6586x driver to new irq_ API
  mfd: Convert tc6393xb driver to new irq_ APIs
  mfd: Convert t7166xb driver to new irq_ API
  ...
2011-01-14 09:08:00 -08:00
Rafael J. Wysocki
b6e335aeeb PCI/PM: Use pm_wakeup_event() directly for reporting wakeup events
After recent changes related to wakeup events pm_wakeup_event()
automatically checks if the given device is configured to signal wakeup,
so pci_wakeup_event() may be a static inline function calling
pm_wakeup_event() directly.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-01-14 08:55:43 -08:00
Rafael J. Wysocki
415e12b237 PCI/ACPI: Request _OSC control once for each root bridge (v3)
Move the evaluation of acpi_pci_osc_control_set() (to request control of
PCI Express native features) into acpi_pci_root_add() to avoid calling
it many times for the same root complex with the same arguments.
Additionally, check if all of the requisite _OSC support bits are set
before calling acpi_pci_osc_control_set() for a given root complex.

References: https://bugzilla.kernel.org/show_bug.cgi?id=20232
Reported-by: Ozan Caglayan <ozan@pardus.org.tr>
Tested-by: Ozan Caglayan <ozan@pardus.org.tr>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-01-14 08:55:41 -08:00
Wolfram Sang
323b7fe8f8 include/gpio.h: remove remaining __must_check-annotiations
Commit 5f829e405e (gpiolib: add missing functions
to generic fallback) also introduced two.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Greg KH <gregkh@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-14 08:06:39 -08:00
KAMEZAWA Hiroyuki
836cb711ad Revert update for dirty_ratio for memcg.
The flags added by commit db16d5ec1f
has no user now. We believe we'll use it soon but considering
patch reviewing, the change itself should be folded into incoming
set of "dirty ratio for memcg" patches.

So, it's better to drop this change from current mainline tree.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-14 07:52:02 -08:00
MyungJoo Ham
359ab9f5b1 power_supply: Add MAX17042 Fuel Gauge Driver
The MAX17042 is a fuel gauge with an I2C interface for lithium-ion
betteries. Unlike its predecessor MAX17040, MAX17042 uses 16bit
registers. Besides, MAX17042 has much more features than MAX17040; e.g.,
a thermistor, current and current accumulation measurement, battery
internal resistance estimate, average values of measurement, and others.

This patch implements a driver for MAX17042.
In this initial release, we have implemented the most basic features of
a fuel gauge: measure the battery capacity and voltage.

Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
2011-01-14 18:11:59 +03:00
Russell King
32385c7cf6 kernel: fix hlist_bl again
__d_rehash is dereferencing an almost-NULL pointer on my ARM926.
CONFIG_SMP=n and CONFIG_DEBUG_SPINLOCK=y.

The faulting instruction is:    strne   r3, [r2, #4]
and as can be seen from the register dump below, r2 is 0x00000001, hence
the faulting 0x00000005 address.

__d_rehash is essentially:

       spin_lock_bucket(b);
       entry->d_flags &= ~DCACHE_UNHASHED;
       hlist_bl_add_head_rcu(&entry->d_hash, &b->head);
       spin_unlock_bucket(b);

which is:

       bit_spin_lock(0, (unsigned long *)&b->head.first);
       entry->d_flags &= ~DCACHE_UNHASHED;
       hlist_bl_add_head_rcu(&entry->d_hash, &b->head);
       __bit_spin_unlock(0, (unsigned long *)&b->head.first);

bit_spin_lock(0, ptr) sets bit 0 of *ptr, in this case b->head.first if
CONFIG_SMP or CONFIG_DEBUG_SPINLOCK is set:

#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
       while (unlikely(test_and_set_bit_lock(bitnum, addr))) {
               while (test_bit(bitnum, addr)) {
                       preempt_enable();
                       cpu_relax();
                       preempt_disable();
               }
       }
#endif

So, b->head.first starts off NULL, and becomes a non-NULL (address 1).
hlist_bl_add_head_rcu() does this:

static inline void hlist_bl_add_head_rcu(struct hlist_bl_node *n,
                                       struct hlist_bl_head *h)
{
       first = hlist_bl_first(h);
       n->next = first;
       if (first)
               first->pprev = &n->next;

It is the store to first->pprev which is faulting.

hlist_bl_first():

static inline struct hlist_bl_node *hlist_bl_first(struct hlist_bl_head *h)
{
       return (struct hlist_bl_node *)
               ((unsigned long)h->first & ~LIST_BL_LOCKMASK);
}

but:
#if defined(CONFIG_SMP)
#define LIST_BL_LOCKMASK        1UL
#else
#define LIST_BL_LOCKMASK        0UL
#endif

So, we have one piece of code which sets bit 0 of addresses, and another
bit of code which doesn't clear it before dereferencing the pointer if
!CONFIG_SMP && CONFIG_DEBUG_SPINLOCK.  With the patch below, I can again
sucessfully boot the kernel on my Versatile PB/926 platform.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-14 13:12:45 +00:00
Mattias Wallin
92d50a4132 mfd: ab8500-core chip version cut 2.0 support
This patch adds support for chip version 2.0 or cut 2.0.
One new interrupt latch register - latch 12 - is introduced.

Signed-off-by: Mattias Wallin <mattias.wallin@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2011-01-14 12:38:18 +01:00
MyungJoo Ham
735a3d9efd 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>
2011-01-14 12:38:16 +01:00
MyungJoo Ham
337ce5d1c5 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>
2011-01-14 12:38:16 +01:00
MyungJoo Ham
cdd137c9c8 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>
2011-01-14 12:38:14 +01:00
Mattias Wallin
e098aded79 mfd: ab8500-core ioresources irq for subdrivers added
This patch adds the ioresources used by subdrivers to
retrieve their interrupt.

Signed-off-by: Mattias Wallin <mattias.wallin@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2011-01-14 12:37:47 +01:00
Mark Brown
4c90aa94f6 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>
2011-01-14 12:37:42 +01:00
Mark Brown
412dc11d3f mfd: Add WM8326 support
The WM8326 is a high performance variant of the WM832x series with
no software visible differences.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2011-01-14 12:37:39 +01:00
Paul Mundt
bba958783b mmc: sh_mmcif: Convert to __raw_xxx() I/O accessors.
When using the I/O accessors in raw mode from the boot stubs we don't
want to bother with any of the complexity associated with readl/writel
and friends. Furthermore, utilization within the context of the host
driver itself is all performed on an ioremapped window, so using the
__raw variants there doesn't pose any problem either.

If and when barriers need to be added in the future, these will need to
be explicitly written out, but this is so far not a concern for any of
the affected CPUs in question.

This fixes up the link error introduced by the ARM tree via its barrier
refactoring:

	arch/arm/boot/compressed/mmcif-sh7372.o: In function `mmcif_loader':
	mmcif-sh7372.c:(.text+0x9e8): undefined reference to `outer_cache

Following the change in:

	http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=6275/1

Reported-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2011-01-14 15:57:47 +09:00
Tobias Klauser
51e7eed79c etherdevice.h: Add is_unicast_ether_addr function
From a check for !is_multicast_ether_addr it is not always obvious that
we're checking for a unicast address. So add this helper function to
make those code paths easier to read.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-13 21:49:56 -08:00
Eric Dumazet
1ac9ad1394 net: remove dev_txq_stats_fold()
After recent changes, (percpu stats on vlan/tunnels...), we dont need
anymore per struct netdev_queue tx_bytes/tx_packets/tx_dropped counters.

Only remaining users are ixgbe, sch_teql, gianfar & macvlan :

1) ixgbe can be converted to use existing tx_ring counters.

2) macvlan incremented txq->tx_dropped, it can use the
dev->stats.tx_dropped counter.

3) sch_teql : almost revert ab35cd4b8f (Use net_device internal stats)
    Now we have ndo_get_stats64(), use it, even for "unsigned long"
fields (No need to bring back a struct net_device_stats)

4) gianfar adds a stats structure per tx queue to hold
tx_bytes/tx_packets

This removes a lockdep warning (and possible lockup) in rndis gadget,
calling dev_get_stats() from hard IRQ context.

Ref: http://www.spinics.net/lists/netdev/msg149202.html

Reported-by: Neil Jones <neiljay@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Jarek Poplawski <jarkao2@gmail.com>
CC: Alexander Duyck <alexander.h.duyck@intel.com>
CC: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
CC: Sandeep Gopalpet <sandeep.kumar@freescale.com>
CC: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-13 21:44:34 -08:00
Linus Torvalds
52cfd503ad 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
  ...
2011-01-13 20:15:35 -08:00
Linus Torvalds
dc8e7e3ec6 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
2011-01-13 20:15:18 -08:00
Linus Torvalds
db9effe99a 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
2011-01-13 20:14:13 -08:00
Nick Piggin
2c6755988a fs: hlist UP debug fixup
Po-Yu Chuang <ratbert.chuang@gmail.com> noticed that hlist_bl_set_first could
crash on a UP system when LIST_BL_LOCKMASK is 0, because

	LIST_BL_BUG_ON(!((unsigned long)h->first & LIST_BL_LOCKMASK));

always evaulates to true.

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.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-14 02:36:43 +00:00
J. Bruce Fields
9ce137eee4 nfsd: don't support msnfs export option
We've long had these pointless #ifdef MSNFS's sprinkled throughout the
code--pointless because MSNFS is always defined (and we give no config
option to make that easy to change).  So we could just remove the
ifdef's and compile the resulting code unconditionally.

But as long as we're there: why not just rip out this code entirely?
The only purpose is to implement the "msnfs" export option which turns
on Windows-like behavior in some cases, and:

	- the export option isn't documented anywhere;
	- the userland utilities (which would need to be able to parse
	  "msnfs" in an export file) don't support it;
	- I don't know how to maintain this, as I don't know what the
	  proper behavior is; and
	- google shows no evidence that anyone has ever used this.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-13 21:04:07 -05:00
Daisuke Nishimura
50de1dd967 memcg: fix memory migration of shmem swapcache
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>
2011-01-13 17:32:51 -08:00
KAMEZAWA Hiroyuki
dbd4ea78f0 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.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Greg Thelen <gthelen@google.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Andrea Righi <arighi@develer.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:50 -08:00
Greg Thelen
2a7106f2cb 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.

Signed-off-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Andrea Righi <arighi@develer.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:50 -08:00
Greg Thelen
db16d5ec1f 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").

                           root_cgroup                    child_cgroup
                 s_read s_write p_read p_write   s_read s_write p_read p_write
mmotm w/o memcg   0.428  0.390   0.429  0.388
mmotm w/ memcg    0.411  0.378   0.391  0.362     0.412  0.377   0.385  0.363
all patches       0.384  0.360   0.370  0.348     0.381  0.363   0.368  0.347
all patches       0.431  0.402   0.427  0.395
  w/o memcg

This patch:

Add additional flags to page_cgroup to track dirty pages within a
mem_cgroup.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrea Righi <arighi@develer.com>
Signed-off-by: Greg Thelen <gthelen@google.com>
Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:50 -08:00
Mel Gorman
29c1f677d4 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
989f89c57e ("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.

[  173.674290] ===================================================
[  173.676016] [ INFO: suspicious rcu_dereference_check() usage. ]
[  173.676016] ---------------------------------------------------
[  173.676016] include/linux/radix-tree.h:145 invoked rcu_dereference_check() without protection!
[  173.676016]
[  173.676016] other info that might help us debug this:
[  173.676016]
[  173.676016]
[  173.676016] rcu_scheduler_active = 1, debug_locks = 0
[  173.676016] 1 lock held by hugeadm/2899:
[  173.676016]  #0:  (&(&inode->i_data.tree_lock)->rlock){..-.-.}, at: [<c10e3d2b>] migrate_page_move_mapping+0x40/0x1ab
[  173.676016]
[  173.676016] stack backtrace:
[  173.676016] Pid: 2899, comm: hugeadm Not tainted 2.6.37-rc5-autobuild
[  173.676016] Call Trace:
[  173.676016]  [<c128cc01>] ? printk+0x14/0x1b
[  173.676016]  [<c1063502>] lockdep_rcu_dereference+0x7d/0x86
[  173.676016]  [<c10e3db5>] migrate_page_move_mapping+0xca/0x1ab
[  173.676016]  [<c10e41ad>] migrate_page+0x23/0x39
[  173.676016]  [<c10e491b>] buffer_migrate_page+0x22/0x107
[  173.676016]  [<c10e48f9>] ? buffer_migrate_page+0x0/0x107
[  173.676016]  [<c10e425d>] move_to_new_page+0x9a/0x1ae
[  173.676016]  [<c10e47e6>] migrate_pages+0x1e7/0x2fa

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>
2011-01-13 17:32:48 -08:00
Andrea Arcangeli
22e5c47ee2 thp: add compound_trans_head() helper
Cleanup some code with common compound_trans_head helper.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:48 -08:00
Andrea Arcangeli
60ab3244ec 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>
2011-01-13 17:32:47 -08:00
Andrea Arcangeli
a664b2d855 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>
2011-01-13 17:32:47 -08:00
Andrea Arcangeli
37c2ac7872 thp: compound_trans_order
Read compound_trans_order safe. Noop for CONFIG_TRANSPARENT_HUGEPAGE=n.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:47 -08:00
Rik van Riel
2c888cfbc1 thp: fix anon memory statistics with transparent hugepages
Count each transparent hugepage as HPAGE_PMD_NR pages in the LRU
statistics, so the Active(anon) and Inactive(anon) statistics in
/proc/meminfo are correct.

Signed-off-by: Rik van Riel <riel@redhat.com>
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>
2011-01-13 17:32:46 -08:00
Andrea Arcangeli
5a03b051ed thp: use compaction in kswapd for GFP_ATOMIC order > 0
This takes advantage of memory compaction to properly generate pages of
order > 0 if regular page reclaim fails and priority level becomes more
severe and we don't reach the proper watermarks.

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>
2011-01-13 17:32:46 -08:00
Andrea Arcangeli
8ee53820ed thp: mmu_notifier_test_young
For GRU and EPT, we need gup-fast to set referenced bit too (this is why
it's correct to return 0 when shadow_access_mask is zero, it requires
gup-fast to set the referenced bit).  qemu-kvm access already sets the
young bit in the pte if it isn't zero-copy, if it's zero copy or a shadow
paging EPT minor fault we relay on gup-fast to signal the page is in
use...

We also need to check the young bits on the secondary pagetables for NPT
and not nested shadow mmu as the data may never get accessed again by the
primary pte.

Without this closer accuracy, we'd have to remove the heuristic that
avoids collapsing hugepages in hugepage virtual regions that have not even
a single subpage in use.

->test_young is full backwards compatible with GRU and other usages that
don't have young bits in pagetables set by the hardware and that should
nuke the secondary mmu mappings when ->clear_flush_young runs just like
EPT does.

Removing the heuristic that checks the young bit in
khugepaged/collapse_huge_page completely isn't so bad either probably but
I thought it was worth it and this makes it reliable.

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>
2011-01-13 17:32:46 -08:00
Andrea Arcangeli
94fcc585fb thp: avoid breaking huge pmd invariants in case of vma_adjust failures
An huge pmd can only be mapped if the corresponding 2M virtual range is
fully contained in the vma.  At times the VM calls split_vma twice, if the
first split_vma succeeds and the second fail, the first split_vma remains
in effect and it's not rolled back.  For split_vma or vma_adjust to fail
an allocation failure is needed so it's a very unlikely event (the out of
memory killer would normally fire before any allocation failure is visible
to kernel and userland and if an out of memory condition happens it's
unlikely to happen exactly here).  Nevertheless it's safer to ensure that
no huge pmd can be left around if the vma is adjusted in a way that can't
fit hugepages anymore at the new vm_start/vm_end address.

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>
2011-01-13 17:32:45 -08:00
Andrea Arcangeli
0bbbc0b33d thp: add numa awareness to hugepage allocations
It's mostly a matter of replacing alloc_pages with alloc_pages_vma after
introducing alloc_pages_vma.  khugepaged needs special handling as the
allocation has to happen inside collapse_huge_page where the vma is known
and an error has to be returned to the outer loop to sleep
alloc_sleep_millisecs in case of failure.  But it retains the more
efficient logic of handling allocation failures in khugepaged in case of
CONFIG_NUMA=n.

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>
2011-01-13 17:32:45 -08:00
Johannes Weiner
cd7548ab36 thp: mprotect: transparent huge page support
Natively handle huge pmds when changing page tables on behalf of
mprotect().

I left out update_mmu_cache() because we do not need it on x86 anyway but
more importantly the interface works on ptes, not pmds.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:44 -08:00
Johannes Weiner
0ca1634d41 thp: mincore transparent hugepage support
Handle transparent huge page pmd entries natively instead of splitting
them into subpages.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:44 -08:00
Johannes Weiner
f2d6bfe9ff thp: add x86 32bit support
Add support for transparent hugepages to x86 32bit.

Share the same VM_ bitflag for VM_MAPPED_COPY.  mm/nommu.c will never
support transparent hugepages.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:44 -08:00
Andrea Arcangeli
5f24ce5fd3 thp: remove PG_buddy
PG_buddy can be converted to _mapcount == -2.  So the PG_compound_lock can
be added to page->flags without overflowing (because of the sparse section
bits increasing) with CONFIG_X86_PAE=y and CONFIG_X86_PAT=y.  This also
has to move the memory hotplug code from _mapcount to lru.next to avoid
any risk of clashes.  We can't use lru.next for PG_buddy removal, but
memory hotplug can use lru.next even more easily than the mapcount
instead.

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>
2011-01-13 17:32:43 -08:00
Andrea Arcangeli
ba76149f47 thp: khugepaged
Add khugepaged to relocate fragmented pages into hugepages if new
hugepages become available.  (this is indipendent of the defrag logic that
will have to make new hugepages available)

The fundamental reason why khugepaged is unavoidable, is that some memory
can be fragmented and not everything can be relocated.  So when a virtual
machine quits and releases gigabytes of hugepages, we want to use those
freely available hugepages to create huge-pmd in the other virtual
machines that may be running on fragmented memory, to maximize the CPU
efficiency at all times.  The scan is slow, it takes nearly zero cpu time,
except when it copies data (in which case it means we definitely want to
pay for that cpu time) so it seems a good tradeoff.

In addition to the hugepages being released by other process releasing
memory, we have the strong suspicion that the performance impact of
potentially defragmenting hugepages during or before each page fault could
lead to more performance inconsistency than allocating small pages at
first and having them collapsed into large pages later...  if they prove
themselfs to be long lived mappings (khugepaged scan is slow so short
lived mappings have low probability to run into khugepaged if compared to
long lived mappings).

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:43 -08:00
Andrea Arcangeli
79134171df thp: transparent hugepage vmstat
Add hugepage stat information to /proc/vmstat and /proc/meminfo.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:43 -08:00
Andrea Arcangeli
500d65d471 thp: pmd_trans_huge migrate bugcheck
No pmd_trans_huge should ever materialize in migration ptes areas, because
we split the hugepage before migration ptes are instantiated.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:42 -08:00
Andrea Arcangeli
0af4e98b6b thp: madvise(MADV_HUGEPAGE)
Add madvise MADV_HUGEPAGE to mark regions that are 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>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:42 -08:00
Andrea Arcangeli
71e3aac072 thp: transparent hugepage core
Lately I've been working to make KVM use hugepages transparently without
the usual restrictions of hugetlbfs.  Some of the restrictions I'd like to
see removed:

1) hugepages have to be swappable or the guest physical memory remains
   locked in RAM and can't be paged out to swap

2) if a hugepage allocation fails, regular pages should be allocated
   instead and mixed in the same vma without any failure and without
   userland noticing

3) if some task quits and more hugepages become available in the
   buddy, guest physical memory backed by regular pages should be
   relocated on hugepages automatically in regions under
   madvise(MADV_HUGEPAGE) (ideally event driven by waking up the
   kernel deamon if the order=HPAGE_PMD_SHIFT-PAGE_SHIFT list becomes
   not null)

4) avoidance of reservation and maximization of use of hugepages whenever
   possible. Reservation (needed to avoid runtime fatal faliures) may be ok for
   1 machine with 1 database with 1 database cache with 1 database cache size
   known at boot time. It's definitely not feasible with a virtualization
   hypervisor usage like RHEV-H that runs an unknown number of virtual machines
   with an unknown size of each virtual machine with an unknown amount of
   pagecache that could be potentially useful in the host for guest not using
   O_DIRECT (aka cache=off).

hugepages in the virtualization hypervisor (and also in the guest!) are
much more important than in a regular host not using virtualization,
becasue with NPT/EPT they decrease the tlb-miss cacheline accesses from 24
to 19 in case only the hypervisor uses transparent hugepages, and they
decrease the tlb-miss cacheline accesses from 19 to 15 in case both the
linux hypervisor and the linux guest both uses this patch (though the
guest will limit the addition speedup to anonymous regions only for
now...).  Even more important is that the tlb miss handler is much slower
on a NPT/EPT guest than for a regular shadow paging or no-virtualization
scenario.  So maximizing the amount of virtual memory cached by the TLB
pays off significantly more with NPT/EPT than without (even if there would
be no significant speedup in the tlb-miss runtime).

The first (and more tedious) part of this work requires allowing the VM to
handle anonymous hugepages mixed with regular pages transparently on
regular anonymous vmas.  This is what this patch tries to achieve in the
least intrusive possible way.  We want hugepages and hugetlb to be used in
a way so that all applications can benefit without changes (as usual we
leverage the KVM virtualization design: by improving the Linux VM at
large, KVM gets the performance boost too).

The most important design choice is: always fallback to 4k allocation if
the hugepage allocation fails!  This is the _very_ opposite of some large
pagecache patches that failed with -EIO back then if a 64k (or similar)
allocation failed...

Second important decision (to reduce the impact of the feature on the
existing pagetable handling code) is that at any time we can split an
hugepage into 512 regular pages and it has to be done with an operation
that can't fail.  This way the reliability of the swapping isn't decreased
(no need to allocate memory when we are short on memory to swap) and it's
trivial to plug a split_huge_page* one-liner where needed without
polluting the VM.  Over time we can teach mprotect, mremap and friends to
handle pmd_trans_huge natively without calling split_huge_page*.  The fact
it can't fail isn't just for swap: if split_huge_page would return -ENOMEM
(instead of the current void) we'd need to rollback the mprotect from the
middle of it (ideally including undoing the split_vma) which would be a
big change and in the very wrong direction (it'd likely be simpler not to
call split_huge_page at all and to teach mprotect and friends to handle
hugepages instead of rolling them back from the middle).  In short the
very value of split_huge_page is that it can't fail.

The collapsing and madvise(MADV_HUGEPAGE) part will remain separated and
incremental and it'll just be an "harmless" addition later if this initial
part is agreed upon.  It also should be noted that locking-wise replacing
regular pages with hugepages is going to be very easy if compared to what
I'm doing below in split_huge_page, as it will only happen when
page_count(page) matches page_mapcount(page) if we can take the PG_lock
and mmap_sem in write mode.  collapse_huge_page will be a "best effort"
that (unlike split_huge_page) can fail at the minimal sign of trouble and
we can try again later.  collapse_huge_page will be similar to how KSM
works and the madvise(MADV_HUGEPAGE) will work similar to
madvise(MADV_MERGEABLE).

The default I like is that transparent hugepages are used at page fault
time.  This can be changed with
/sys/kernel/mm/transparent_hugepage/enabled.  The control knob can be set
to three values "always", "madvise", "never" which mean respectively that
hugepages are always used, or only inside madvise(MADV_HUGEPAGE) regions,
or never used.  /sys/kernel/mm/transparent_hugepage/defrag instead
controls if the hugepage allocation should defrag memory aggressively
"always", only inside "madvise" regions, or "never".

The pmd_trans_splitting/pmd_trans_huge locking is very solid.  The
put_page (from get_user_page users that can't use mmu notifier like
O_DIRECT) that runs against a __split_huge_page_refcount instead was a
pain to serialize in a way that would result always in a coherent page
count for both tail and head.  I think my locking solution with a
compound_lock taken only after the page_first is valid and is still a
PageHead should be safe but it surely needs review from SMP race point of
view.  In short there is no current existing way to serialize the O_DIRECT
final put_page against split_huge_page_refcount so I had to invent a new
one (O_DIRECT loses knowledge on the mapping status by the time gup_fast
returns so...).  And I didn't want to impact all gup/gup_fast users for
now, maybe if we change the gup interface substantially we can avoid this
locking, I admit I didn't think too much about it because changing the gup
unpinning interface would be invasive.

If we ignored O_DIRECT we could stick to the existing compound refcounting
code, by simply adding a get_user_pages_fast_flags(foll_flags) where KVM
(and any other mmu notifier user) would call it without FOLL_GET (and if
FOLL_GET isn't set we'd just BUG_ON if nobody registered itself in the
current task mmu notifier list yet).  But O_DIRECT is fundamental for
decent performance of virtualized I/O on fast storage so we can't avoid it
to solve the race of put_page against split_huge_page_refcount to achieve
a complete hugepage feature for KVM.

Swap and oom works fine (well just like with regular pages ;).  MMU
notifier is handled transparently too, with the exception of the young bit
on the pmd, that didn't have a range check but I think KVM will be fine
because the whole point of hugepages is that EPT/NPT will also use a huge
pmd when they notice gup returns pages with PageCompound set, so they
won't care of a range and there's just the pmd young bit to check in that
case.

NOTE: in some cases if the L2 cache is small, this may slowdown and waste
memory during COWs because 4M of memory are accessed in a single fault
instead of 8k (the payoff is that after COW the program can run faster).
So we might want to switch the copy_huge_page (and clear_huge_page too) to
not temporal stores.  I also extensively researched ways to avoid this
cache trashing with a full prefault logic that would cow in 8k/16k/32k/64k
up to 1M (I can send those patches that fully implemented prefault) but I
concluded they're not worth it and they add an huge additional complexity
and they remove all tlb benefits until the full hugepage has been faulted
in, to save a little bit of memory and some cache during app startup, but
they still don't improve substantially the cache-trashing during startup
if the prefault happens in >4k chunks.  One reason is that those 4k pte
entries copied are still mapped on a perfectly cache-colored hugepage, so
the trashing is the worst one can generate in those copies (cow of 4k page
copies aren't so well colored so they trashes less, but again this results
in software running faster after the page fault).  Those prefault patches
allowed things like a pte where post-cow pages were local 4k regular anon
pages and the not-yet-cowed pte entries were pointing in the middle of
some hugepage mapped read-only.  If it doesn't payoff substantially with
todays hardware it will payoff even less in the future with larger l2
caches, and the prefault logic would blot the VM a lot.  If one is
emebdded transparent_hugepage can be disabled during boot with sysfs or
with the boot commandline parameter transparent_hugepage=0 (or
transparent_hugepage=2 to restrict hugepages inside madvise regions) that
will ensure not a single hugepage is allocated at boot time.  It is simple
enough to just disable transparent hugepage globally and let transparent
hugepages be allocated selectively by applications in the MADV_HUGEPAGE
region (both at page fault time, and if enabled with the
collapse_huge_page too through the kernel daemon).

This patch supports only hugepages mapped in the pmd, archs that have
smaller hugepages will not fit in this patch alone.  Also some archs like
power have certain tlb limits that prevents mixing different page size in
the same regions so they will not fit in this framework that requires
"graceful fallback" to basic PAGE_SIZE in case of physical memory
fragmentation.  hugetlbfs remains a perfect fit for those because its
software limits happen to match the hardware limits.  hugetlbfs also
remains a perfect fit for hugepage sizes like 1GByte that cannot be hoped
to be found not fragmented after a certain system uptime and that would be
very expensive to defragment with relocation, so requiring reservation.
hugetlbfs is the "reservation way", the point of transparent hugepages is
not to have any reservation at all and maximizing the use of cache and
hugepages at all times automatically.

Some performance result:

vmx andrea # LD_PRELOAD=/usr/lib64/libhugetlbfs.so HUGETLB_MORECORE=yes HUGETLB_PATH=/mnt/huge/ ./largep
ages3
memset page fault 1566023
memset tlb miss 453854
memset second tlb miss 453321
random access tlb miss 41635
random access second tlb miss 41658
vmx andrea # LD_PRELOAD=/usr/lib64/libhugetlbfs.so HUGETLB_MORECORE=yes HUGETLB_PATH=/mnt/huge/ ./largepages3
memset page fault 1566471
memset tlb miss 453375
memset second tlb miss 453320
random access tlb miss 41636
random access second tlb miss 41637
vmx andrea # ./largepages3
memset page fault 1566642
memset tlb miss 453417
memset second tlb miss 453313
random access tlb miss 41630
random access second tlb miss 41647
vmx andrea # ./largepages3
memset page fault 1566872
memset tlb miss 453418
memset second tlb miss 453315
random access tlb miss 41618
random access second tlb miss 41659
vmx andrea # echo 0 > /proc/sys/vm/transparent_hugepage
vmx andrea # ./largepages3
memset page fault 2182476
memset tlb miss 460305
memset second tlb miss 460179
random access tlb miss 44483
random access second tlb miss 44186
vmx andrea # ./largepages3
memset page fault 2182791
memset tlb miss 460742
memset second tlb miss 459962
random access tlb miss 43981
random access second tlb miss 43988

============
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>

#define SIZE (3UL*1024*1024*1024)

int main()
{
	char *p = malloc(SIZE), *p2;
	struct timeval before, after;

	gettimeofday(&before, NULL);
	memset(p, 0, SIZE);
	gettimeofday(&after, NULL);
	printf("memset page fault %Lu\n",
	       (after.tv_sec-before.tv_sec)*1000000UL +
	       after.tv_usec-before.tv_usec);

	gettimeofday(&before, NULL);
	memset(p, 0, SIZE);
	gettimeofday(&after, NULL);
	printf("memset tlb miss %Lu\n",
	       (after.tv_sec-before.tv_sec)*1000000UL +
	       after.tv_usec-before.tv_usec);

	gettimeofday(&before, NULL);
	memset(p, 0, SIZE);
	gettimeofday(&after, NULL);
	printf("memset second tlb miss %Lu\n",
	       (after.tv_sec-before.tv_sec)*1000000UL +
	       after.tv_usec-before.tv_usec);

	gettimeofday(&before, NULL);
	for (p2 = p; p2 < p+SIZE; p2 += 4096)
		*p2 = 0;
	gettimeofday(&after, NULL);
	printf("random access tlb miss %Lu\n",
	       (after.tv_sec-before.tv_sec)*1000000UL +
	       after.tv_usec-before.tv_usec);

	gettimeofday(&before, NULL);
	for (p2 = p; p2 < p+SIZE; p2 += 4096)
		*p2 = 0;
	gettimeofday(&after, NULL);
	printf("random access second tlb miss %Lu\n",
	       (after.tv_sec-before.tv_sec)*1000000UL +
	       after.tv_usec-before.tv_usec);

	return 0;
}
============

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:42 -08:00
Andrea Arcangeli
32dba98e08 thp: _GFP_NO_KSWAPD
Transparent hugepage allocations must be allowed not to invoke kswapd or
any other kind of indirect reclaim (especially when the defrag sysfs is
control disabled).  It's unacceptable to swap out anonymous pages
(potentially anonymous transparent hugepages) in order to create new
transparent hugepages.  This is true for the MADV_HUGEPAGE areas too
(swapping out a kvm virtual machine and so having it suffer an unbearable
slowdown, so another one with guest physical memory marked MADV_HUGEPAGE
can run 30% faster if it is running memory intensive workloads, makes no
sense).  If a transparent hugepage allocation fails the slowdown is minor
and there is total fallback, so kswapd should never be asked to swapout
memory to allow the high order allocation to succeed.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:41 -08:00
Andrea Arcangeli
936a5fe6e6 thp: kvm mmu transparent hugepage support
This should work for both hugetlbfs and transparent hugepages.

[akpm@linux-foundation.org: bring forward PageTransCompound() addition for bisectability]
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:41 -08:00
Andrea Arcangeli
47ad8475c0 thp: clear_copy_huge_page
Move the copy/clear_huge_page functions to common code to share between
hugetlb.c and huge_memory.c.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:41 -08:00
Andrea Arcangeli
e7a00c45f2 thp: add pmd_huge_pte to mm_struct
This increase the size of the mm struct a bit but it is needed to
preallocate one pte for each hugepage so that split_huge_page will not
require a fail path.  Guarantee of success is a fundamental property of
split_huge_page to avoid decrasing swapping reliability and to avoid
adding -ENOMEM fail paths that would otherwise force the hugepage-unaware
VM code to learn rolling back in the middle of its pte mangling operations
(if something we need it to learn handling pmd_trans_huge natively rather
being capable of rollback).  When split_huge_page runs a pte is needed to
succeed the split, to map the newly splitted regular pages with a regular
pte.  This way all existing VM code remains backwards compatible by just
adding a split_huge_page* one liner.  The memory waste of those
preallocated ptes is negligible and so it is worth it.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:41 -08:00
Andrea Arcangeli
4e6af67e97 thp: clear page compound
split_huge_page must transform a compound page to a regular page and needs
ClearPageCompound.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:41 -08:00
Andrea Arcangeli
91a4ee2670 thp: add pmd mmu_notifier helpers
Add mmu notifier helpers to handle pmd huge operations.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:41 -08:00
Andrea Arcangeli
8ac1f8320a thp: pte alloc trans splitting
pte alloc routines must wait for split_huge_page if the pmd is not present
and not null (i.e.  pmd_trans_splitting).  The additional branches are
optimized away at compile time by pmd_trans_splitting if the config option
is off.  However we must pass the vma down in order to know the anon_vma
lock to wait for.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:40 -08:00
Andrea Arcangeli
14fd403f21 thp: export maybe_mkwrite
huge_memory.c needs it too when it fallbacks in copying hugepages into
regular fragmented pages if hugepage allocation fails during COW.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:39 -08:00
Andrea Arcangeli
9180706344 thp: alter compound get_page/put_page
Alter compound get_page/put_page to keep references on subpages too, in
order to allow __split_huge_page_refcount to split an hugepage even while
subpages have been pinned by one of the get_user_pages() variants.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:39 -08:00
Andrea Arcangeli
e9da73d677 thp: compound_lock
Add a new compound_lock() needed to serialize put_page against
__split_huge_page_refcount().

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:38 -08:00
Mel Gorman
9950474883 mm: kswapd: stop high-order balancing when any suitable zone is balanced
Simon Kirby reported the following problem

   We're seeing cases on a number of servers where cache never fully
   grows to use all available memory.  Sometimes we see servers with 4 GB
   of memory that never seem to have less than 1.5 GB free, even with a
   constantly-active VM.  In some cases, these servers also swap out while
   this happens, even though they are constantly reading the working set
   into memory.  We have been seeing this happening for a long time; I
   don't think it's anything recent, and it still happens on 2.6.36.

After some debugging work by Simon, Dave Hansen and others, the prevaling
theory became that kswapd is reclaiming order-3 pages requested by SLUB
too aggressive about it.

There are two apparent problems here.  On the target machine, there is a
small Normal zone in comparison to DMA32.  As kswapd tries to balance all
zones, it would continually try reclaiming for Normal even though DMA32
was balanced enough for callers.  The second problem is that
sleeping_prematurely() does not use the same logic as balance_pgdat() when
deciding whether to sleep or not.  This keeps kswapd artifically awake.

A number of tests were run and the figures from previous postings will
look very different for a few reasons.  One, the old figures were forcing
my network card to use GFP_ATOMIC in attempt to replicate Simon's problem.
 Second, I previous specified slub_min_order=3 again in an attempt to
reproduce Simon's problem.  In this posting, I'm depending on Simon to say
whether his problem is fixed or not and these figures are to show the
impact to the ordinary cases.  Finally, the "vmscan" figures are taken
from /proc/vmstat instead of the tracepoints.  There is less information
but recording is less disruptive.

The first test of relevance was postmark with a process running in the
background reading a large amount of anonymous memory in blocks.  The
objective was to vaguely simulate what was happening on Simon's machine
and it's memory intensive enough to have kswapd awake.

POSTMARK
                                            traceonly          kanyzone
Transactions per second:              156.00 ( 0.00%)   153.00 (-1.96%)
Data megabytes read per second:        21.51 ( 0.00%)    21.52 ( 0.05%)
Data megabytes written per second:     29.28 ( 0.00%)    29.11 (-0.58%)
Files created alone per second:       250.00 ( 0.00%)   416.00 (39.90%)
Files create/transact per second:      79.00 ( 0.00%)    76.00 (-3.95%)
Files deleted alone per second:       520.00 ( 0.00%)   420.00 (-23.81%)
Files delete/transact per second:      79.00 ( 0.00%)    76.00 (-3.95%)

MMTests Statistics: duration
User/Sys Time Running Test (seconds)         16.58      17.4
Total Elapsed Time (seconds)                218.48    222.47

VMstat Reclaim Statistics: vmscan
Direct reclaims                                  0          4
Direct reclaim pages scanned                     0        203
Direct reclaim pages reclaimed                   0        184
Kswapd pages scanned                        326631     322018
Kswapd pages reclaimed                      312632     309784
Kswapd low wmark quickly                         1          4
Kswapd high wmark quickly                      122        475
Kswapd skip congestion_wait                      1          0
Pages activated                             700040     705317
Pages deactivated                           212113     203922
Pages written                                 9875       6363

Total pages scanned                         326631    322221
Total pages reclaimed                       312632    309968
%age total pages scanned/reclaimed          95.71%    96.20%
%age total pages scanned/written             3.02%     1.97%

proc vmstat: Faults
Major Faults                                   300       254
Minor Faults                                645183    660284
Page ins                                    493588    486704
Page outs                                  4960088   4986704
Swap ins                                      1230       661
Swap outs                                     9869      6355

Performance is mildly affected because kswapd is no longer doing as much
work and the background memory consumer process is getting in the way.
Note that kswapd scanned and reclaimed fewer pages as it's less aggressive
and overall fewer pages were scanned and reclaimed.  Swap in/out is
particularly reduced again reflecting kswapd throwing out fewer pages.

The slight performance impact is unfortunate here but it looks like a
direct result of kswapd being less aggressive.  As the bug report is about
too many pages being freed by kswapd, it may have to be accepted for now.

The second test is a streaming IO benchmark that was previously used by
Johannes to show regressions in page reclaim.

MICRO
					 traceonly  kanyzone
User/Sys Time Running Test (seconds)         29.29     28.87
Total Elapsed Time (seconds)                492.18    488.79

VMstat Reclaim Statistics: vmscan
Direct reclaims                               2128       1460
Direct reclaim pages scanned               2284822    1496067
Direct reclaim pages reclaimed              148919     110937
Kswapd pages scanned                      15450014   16202876
Kswapd pages reclaimed                     8503697    8537897
Kswapd low wmark quickly                      3100       3397
Kswapd high wmark quickly                     1860       7243
Kswapd skip congestion_wait                    708        801
Pages activated                               9635       9573
Pages deactivated                             1432       1271
Pages written                                  223       1130

Total pages scanned                       17734836  17698943
Total pages reclaimed                      8652616   8648834
%age total pages scanned/reclaimed          48.79%    48.87%
%age total pages scanned/written             0.00%     0.01%

proc vmstat: Faults
Major Faults                                   165       221
Minor Faults                               9655785   9656506
Page ins                                      3880      7228
Page outs                                 37692940  37480076
Swap ins                                         0        69
Swap outs                                       19        15

Again fewer pages are scanned and reclaimed as expected and this time the
test completed faster.  Note that kswapd is hitting its watermarks faster
(low and high wmark quickly) which I expect is due to kswapd reclaiming
fewer pages.

I also ran fs-mark, iozone and sysbench but there is nothing interesting
to report in the figures.  Performance is not significantly changed and
the reclaim statistics look reasonable.

Tgis patch:

When the allocator enters its slow path, kswapd is woken up to balance the
node.  It continues working until all zones within the node are balanced.
For order-0 allocations, this makes perfect sense but for higher orders it
can have unintended side-effects.  If the zone sizes are imbalanced,
kswapd may reclaim heavily within a smaller zone discarding an excessive
number of pages.  The user-visible behaviour is that kswapd is awake and
reclaiming even though plenty of pages are free from a suitable zone.

This patch alters the "balance" logic for high-order reclaim allowing
kswapd to stop if any suitable zone becomes balanced to reduce the number
of pages it reclaims from other zones.  kswapd still tries to ensure that
order-0 watermarks for all zones are met before sleeping.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Eric B Munson <emunson@mgebm.net>
Cc: Simon Kirby <sim@hostway.ca>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:37 -08:00
Steven Rostedt
e20e877958 mm: remove unlikely() from page_mapping()
page_mapping() has a unlikely that the mapping has PAGE_MAPPING_ANON set.
But running the annotated branch profiler on a normal desktop system doing
vairous tasks (xchat, evolution, firefox, distcc), it is not really that
unlikely that the mapping here will have the PAGE_MAPPING_ANON flag set:

 correct incorrect  %        Function                  File              Line
 ------- ---------  -        --------                  ----              ----
35935762 1270265395  97 page_mapping                   mm.h                 659
1306198001   143659   0 page_mapping                   mm.h                 657
203131478   121586   0 page_mapping                   mm.h                 657
 5415491     1116   0 page_mapping                   mm.h                 657
74899487     1116   0 page_mapping                   mm.h                 657
203132845      224   0 page_mapping                   mm.h                 659
 5415464       27   0 page_mapping                   mm.h                 659
   13552        0   0 page_mapping                   mm.h                 657
   13552        0   0 page_mapping                   mm.h                 659
  242630        0   0 page_mapping                   mm.h                 657
  242630        0   0 page_mapping                   mm.h                 659
74899487        0   0 page_mapping                   mm.h                 659

The page_mapping() is a static inline, which is why it shows up multiple
times.

The unlikely in page_mapping() was correct a total of 1909540379 times and
incorrect 1270533123 times, with a 39% being incorrect.  With this much of
an error, it's best to simply remove the unlikely and have the compiler
and branch prediction figure this out.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Rik van Riel <riel@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:36 -08:00
Steven Rostedt
088e54658f mm: remove likely() from mapping_unevictable()
The mapping_unevictable() has a likely() around the mapping parameter.
This mapping parameter comes from page_mapping() which has an unlikely()
that the page will be set as PAGE_MAPPING_ANON, and if so, it will return
NULL.  One would think that this unlikely() means that the mapping
returned by page_mapping() would not be NULL, but where page_mapping() is
used just above mapping_unevictable(), that unlikely() is incorrect most
of the time.  This means that the "likely(mapping)" in
mapping_unevictable() is incorrect most of the time.

Running the annotated branch profiler on my main box which runs firefox,
evolution, xchat and is part of my distcc farm, I had this:

 correct incorrect  %        Function                  File              Line
 ------- ---------  -        --------                  ----              ----
12872836 1269443893  98 mapping_unevictable            pagemap.h            51
35935762 1270265395  97 page_mapping                   mm.h                 659
1306198001   143659   0 page_mapping                   mm.h                 657
203131478   121586   0 page_mapping                   mm.h                 657
 5415491     1116   0 page_mapping                   mm.h                 657
74899487     1116   0 page_mapping                   mm.h                 657
203132845      224   0 page_mapping                   mm.h                 659
 5415464       27   0 page_mapping                   mm.h                 659
   13552        0   0 page_mapping                   mm.h                 657
   13552        0   0 page_mapping                   mm.h                 659
  242630        0   0 page_mapping                   mm.h                 657
  242630        0   0 page_mapping                   mm.h                 659
74899487        0   0 page_mapping                   mm.h                 659

The page_mapping() is a static inline, which is why it shows up multiple
times.  The mapping_unevictable() is also a static inline but seems to be
used only once in my setup.

The unlikely in page_mapping() was correct a total of 1909540379 times and
incorrect 1270533123 times, with a 39% being incorrect.  Perhaps this is
enough to remove the unlikely from page_mapping() as well.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Nick Piggin <npiggin@kernel.dk>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:36 -08:00
Michel Lespinasse
110d74a921 mm: add FOLL_MLOCK follow_page flag.
Move the code to mlock pages from __mlock_vma_pages_range() to
follow_page().

This allows __mlock_vma_pages_range() to not have to break down work into
16-page batches.

An additional motivation for doing this within the present patch series is
that it'll make it easier for a later chagne to drop mmap_sem when
blocking on disk (we'd like to be able to resume at the page that was read
from disk instead of at the start of a 16-page batch).

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:36 -08:00
Rik van Riel
212260aa07 mm: clear PageError bit in msync & fsync
Temporary IO failures, eg.  due to loss of both multipath paths, can
permanently leave the PageError bit set on a page, resulting in msync or
fsync returning -EIO over and over again, even if IO is now getting to the
disk correctly.

We already clear the AS_ENOSPC and AS_IO bits in mapping->flags in the
filemap_fdatawait_range function.  Also clearing the PageError bit on the
page allows subsequent msync or fsync calls on this file to return without
an error, if the subsequent IO succeeds.

Unfortunately data written out in the msync or fsync call that returned
-EIO can still get lost, because the page dirty bit appears to not get
restored on IO error.  However, the alternative could be potentially all
of memory filling up with uncleanable dirty pages, hanging the system, so
there is no nice choice here...

Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Valerie Aurora <vaurora@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:35 -08:00
Mandeep Singh Baines
dabb16f639 oom: allow a non-CAP_SYS_RESOURCE proces to oom_score_adj down
We'd like to be able to oom_score_adj a process up/down as it
enters/leaves the foreground.  Currently, it is not possible to oom_adj
down without CAP_SYS_RESOURCE.  This patch allows a task to decrease its
oom_score_adj back to the value that a CAP_SYS_RESOURCE thread set it to
or its inherited value at fork.  Assuming the thread that has forked it
has oom_score_adj of 0, each process could decrease it back from 0 upon
activation unless a CAP_SYS_RESOURCE thread elevated it to something
higher.

Alternative considered:

* a setuid binary
* a daemon with CAP_SYS_RESOURCE

Since you don't wan't all processes to be able to reduce their oom_adj, a
setuid or daemon implementation would be complex.  The alternatives also
have much higher overhead.

This patch updated from original patch based on feedback from David
Rientjes.

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ying Han <yinghan@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:35 -08:00
David Rientjes
d0a21265df mm: unify module_alloc code for vmalloc
Four architectures (arm, mips, sparc, x86) use __vmalloc_area() for
module_init().  Much of the code is duplicated and can be generalized in a
globally accessible function, __vmalloc_node_range().

__vmalloc_node() now calls into __vmalloc_node_range() with a range of
[VMALLOC_START, VMALLOC_END) for functionally equivalent behavior.

Each architecture may then use __vmalloc_node_range() directly to remove
the duplication of code.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:34 -08:00
David Rientjes
ec3f64fc9c mm: remove gfp mask from pcpu_get_vm_areas
pcpu_get_vm_areas() only uses GFP_KERNEL allocations, so remove the gfp_t
formal and use the mask internally.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:34 -08:00
David Rientjes
e5a5623b28 mm: remove unused get_vm_area_node
get_vm_area_node() is unused in the kernel and can thus be removed.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:34 -08:00
Mel Gorman
7f0f24967b mm: migration: cleanup migrate_pages API by matching types for offlining and sync
With the introduction of the boolean sync parameter, the API looks a
little inconsistent as offlining is still an int.  Convert offlining to a
bool for the sake of being tidy.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:34 -08:00
Mel Gorman
77f1fe6b08 mm: migration: allow migration to operate asynchronously and avoid synchronous compaction in the faster path
Migration synchronously waits for writeback if the initial passes fails.
Callers of memory compaction do not necessarily want this behaviour if the
caller is latency sensitive or expects that synchronous migration is not
going to have a significantly better success rate.

This patch adds a sync parameter to migrate_pages() allowing the caller to
indicate if wait_on_page_writeback() is allowed within migration or not.
For reclaim/compaction, try_to_compact_pages() is first called
asynchronously, direct reclaim runs and then try_to_compact_pages() is
called synchronously as there is a greater expectation that it'll succeed.

[akpm@linux-foundation.org: build/merge fix]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:34 -08:00
Mel Gorman
3e7d344970 mm: vmscan: reclaim order-0 and use compaction instead of lumpy reclaim
Lumpy reclaim is disruptive.  It reclaims a large number of pages and
ignores the age of the pages it reclaims.  This can incur significant
stalls and potentially increase the number of major faults.

Compaction has reached the point where it is considered reasonably stable
(meaning it has passed a lot of testing) and is a potential candidate for
displacing lumpy reclaim.  This patch introduces an alternative to lumpy
reclaim whe compaction is available called reclaim/compaction.  The basic
operation is very simple - instead of selecting a contiguous range of
pages to reclaim, a number of order-0 pages are reclaimed and then
compaction is later by either kswapd (compact_zone_order()) or direct
compaction (__alloc_pages_direct_compact()).

[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: use conventional task_struct naming]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:33 -08:00
Mel Gorman
b44129b306 mm: vmstat: use a single setter function and callback for adjusting percpu thresholds
reduce_pgdat_percpu_threshold() and restore_pgdat_percpu_threshold() exist
to adjust the per-cpu vmstat thresholds while kswapd is awake to avoid
errors due to counter drift.  The functions duplicate some code so this
patch replaces them with a single set_pgdat_percpu_threshold() that takes
a callback function to calculate the desired threshold as a parameter.

[akpm@linux-foundation.org: readability tweak]
[kosaki.motohiro@jp.fujitsu.com: set_pgdat_percpu_threshold(): don't use for_each_online_cpu]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Christoph Lameter <cl@linux.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:31 -08:00
Mel Gorman
88f5acf88a mm: page allocator: adjust the per-cpu counter threshold when memory is low
Commit aa45484 ("calculate a better estimate of NR_FREE_PAGES when memory
is low") noted that watermarks were based on the vmstat NR_FREE_PAGES.  To
avoid synchronization overhead, these counters are maintained on a per-cpu
basis and drained both periodically and when a threshold is above a
threshold.  On large CPU systems, the difference between the estimate and
real value of NR_FREE_PAGES can be very high.  The system can get into a
case where pages are allocated far below the min watermark potentially
causing livelock issues.  The commit solved the problem by taking a better
reading of NR_FREE_PAGES when memory was low.

Unfortately, as reported by Shaohua Li this accurate reading can consume a
large amount of CPU time on systems with many sockets due to cache line
bouncing.  This patch takes a different approach.  For large machines
where counter drift might be unsafe and while kswapd is awake, the per-cpu
thresholds for the target pgdat are reduced to limit the level of drift to
what should be a safe level.  This incurs a performance penalty in heavy
memory pressure by a factor that depends on the workload and the machine
but the machine should function correctly without accidentally exhausting
all memory on a node.  There is an additional cost when kswapd wakes and
sleeps but the event is not expected to be frequent - in Shaohua's test
case, there was one recorded sleep and wake event at least.

To ensure that kswapd wakes up, a safe version of zone_watermark_ok() is
introduced that takes a more accurate reading of NR_FREE_PAGES when called
from wakeup_kswapd, when deciding whether it is really safe to go back to
sleep in sleeping_prematurely() and when deciding if a zone is really
balanced or not in balance_pgdat().  We are still using an expensive
function but limiting how often it is called.

When the test case is reproduced, the time spent in the watermark
functions is reduced.  The following report is on the percentage of time
spent cumulatively spent in the functions zone_nr_free_pages(),
zone_watermark_ok(), __zone_watermark_ok(), zone_watermark_ok_safe(),
zone_page_state_snapshot(), zone_page_state().

vanilla                      11.6615%
disable-threshold            0.2584%

David said:

: We had to pull aa454840 "mm: page allocator: calculate a better estimate
: of NR_FREE_PAGES when memory is low and kswapd is awake" from 2.6.36
: internally because tests showed that it would cause the machine to stall
: as the result of heavy kswapd activity.  I merged it back with this fix as
: it is pending in the -mm tree and it solves the issue we were seeing, so I
: definitely think this should be pushed to -stable (and I would seriously
: consider it for 2.6.37 inclusion even at this late date).

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reported-by: Shaohua Li <shaohua.li@intel.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Tested-by: Nicolas Bareil <nico@chdir.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: <stable@kernel.org>		[2.6.37.1, 2.6.36.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:31 -08:00
Dave Jones
43bb40c9e3 sched: remove long deprecated CLONE_STOPPED flag
This warning was added in commit bdff746a39 ("clone: prepare to recycle
CLONE_STOPPED") three years ago.  2.6.26 came and went.  As far as I know,
no-one is actually using CLONE_STOPPED.

Signed-off-by: Dave Jones <davej@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:31 -08:00
Eric Dumazet
6c9ae009b2 irq: use per_cpu kstat_irqs
Use modern per_cpu API to increment {soft|hard}irq counters, and use
per_cpu allocation for (struct irq_desc)->kstats_irq instead of an array.

This gives better SMP/NUMA locality and saves few instructions per irq.

With small nr_cpuids values (8 for example), kstats_irq was a small array
(less than L1_CACHE_BYTES), potentially source of false sharing.

In the !CONFIG_SPARSE_IRQ case, remove the huge, NUMA/cache unfriendly
kstat_irqs_all[NR_IRQS][NR_CPUS] array.

Note: we still populate kstats_irq for all possible irqs in
early_irq_init().  We probably could use on-demand allocations.  (Code
included in alloc_descs()).  Problem is not all IRQS are used with a prior
alloc_descs() call.

kstat_irqs_this_cpu() is not used anymore, remove it.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:31 -08:00
Linus Torvalds
f6bcfd94c0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm: (32 commits)
  dm: raid456 basic support
  dm: per target unplug callback support
  dm: introduce target callbacks and congestion callback
  dm mpath: delay activate_path retry on SCSI_DH_RETRY
  dm: remove superfluous irq disablement in dm_request_fn
  dm log: use PTR_ERR value instead of ENOMEM
  dm snapshot: avoid storing private suspended state
  dm snapshot: persistent make metadata_wq multithreaded
  dm: use non reentrant workqueues if equivalent
  dm: convert workqueues to alloc_ordered
  dm stripe: switch from local workqueue to system_wq
  dm: dont use flush_scheduled_work
  dm snapshot: remove unused dm_snapshot queued_bios_work
  dm ioctl: suppress needless warning messages
  dm crypt: add loop aes iv generator
  dm crypt: add multi key capability
  dm crypt: add post iv call to iv generator
  dm crypt: use io thread for reads only if mempool exhausted
  dm crypt: scale to multiple cpus
  dm crypt: simplify compatible table output
  ...
2011-01-13 17:30:47 -08:00
Linus Torvalds
d8a3515e2a Revert "gpiolib: annotate gpio-intialization with __must_check"
This reverts commit 0fdae42d36, which
wasn't really supposed to go in, and causes lots of annoying warnings.

Quoth Andrew:
  "Complete brainfart - I meant to drop that patch ages ago."

Quoth Greg:
  "Ick, yeah, that patch isn't ok to go in as-is, all of the callers
   need to be fixed up first, which is what I thought we had agreed on..."

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:26:46 -08:00
Amitkumar Karwar
8d661f1e46 ieee80211: correct IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK macro
It is defined in include/linux/ieee80211.h. As per IEEE spec.
bit6 to bit15 in block ack parameter represents buffer size.
So the bitmask should be 0xFFC0.

Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Cc: stable@kernel.org
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-01-13 15:46:45 -05:00
NeilBrown
99d03c141b dm: per target unplug callback support
Add per-target unplug callback support.

Cc: linux-raid@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13 20:00:02 +00:00
NeilBrown
9d357b0787 dm: introduce target callbacks and congestion callback
DM currently implements congestion checking by checking on congestion
in each component device.  For raid456 we need to also check if the
stripe cache is congested.

Add per-target congestion checker callback support.

Extending the target_callbacks structure with additional callback
functions allows for establishing multiple callbacks per-target (a
callback is also needed for unplug).

Cc: linux-raid@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13 20:00:01 +00:00
Tejun Heo
9c4376de98 dm: use non reentrant workqueues if equivalent
kmirrord_wq, kcopyd_work and md->wq are created per dm instance and
serve only a single work item from the dm instance, so non-reentrant
workqueues would provide the same ordering guarantees as ordered ones
while allowing CPU affinity and use of the workqueues for other
purposes.  Switch them to non-reentrant workqueues.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13 19:59:58 +00:00
Jonathan Brassow
86a54a4802 dm log userspace: add version number to comms
This patch adds a 'version' field to the 'dm_ulog_request'
structure.

The 'version' field is taken from a portion of the unused
'padding' field in the 'dm_ulog_request' structure.  This
was done to avoid changing the size of the structure and
possibly disrupting backwards compatibility.

The version number will help notify user-space daemons
when a change has been made to the kernel/userspace
log API.

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13 19:59:52 +00:00
Peter Jones
84c89557a3 dm ioctl: allow rename to fill empty uuid
Allow the uuid of a mapped device to be set after device creation.
Previously the uuid (which is optional) could only be set by
DM_DEV_CREATE.  If no uuid was supplied it could not be set later.

Sometimes it's necessary to create the device before the uuid is known,
and in such cases the uuid must be filled in after the creation.

This patch extends DM_DEV_RENAME to accept a uuid accompanied by
a new flag DM_UUID_FLAG.  This can only be done once and if no
uuid was previously supplied.  It cannot be used to change an
existing uuid.

DM_VERSION_MINOR is also bumped to 19 to indicate this interface
extension is available.

Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13 19:59:47 +00:00
Linus Torvalds
275220f0fc Merge branch 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block: (43 commits)
  block: ensure that completion error gets properly traced
  blktrace: add missing probe argument to block_bio_complete
  block cfq: don't use atomic_t for cfq_group
  block cfq: don't use atomic_t for cfq_queue
  block: trace event block fix unassigned field
  block: add internal hd part table references
  block: fix accounting bug on cross partition merges
  kref: add kref_test_and_get
  bio-integrity: mark kintegrityd_wq highpri and CPU intensive
  block: make kblockd_workqueue smarter
  Revert "sd: implement sd_check_events()"
  block: Clean up exit_io_context() source code.
  Fix compile warnings due to missing removal of a 'ret' variable
  fs/block: type signature of major_to_index(int) to major_to_index(unsigned)
  block: convert !IS_ERR(p) && p to !IS_ERR_NOR_NULL(p)
  cfq-iosched: don't check cfqg in choose_service_tree()
  fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors
  cdrom: export cdrom_check_events()
  sd: implement sd_check_events()
  sr: implement sr_check_events()
  ...
2011-01-13 10:45:01 -08:00
Linus Torvalds
86f6f9b64a Merge branch 'sh-latest' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6
* 'sh-latest' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (31 commits)
  sh: Add support for AP-SH4AD-0A board.
  sh: Add support for AP-SH4A-3A board.
  sh: Add a new mach type for alpha project boards.
  serial: sh-sci: build fixes.
  sh: sh7372 SH4AL-DSP probe support
  sh: sh7366 Enable SDIO IRQs
  sh: sh7343 Enable SDIO IRQs
  sh: mach-ecovec24: enable runtime PM for SDHI
  sh: sh7723 / ap325rxa enable SDIO IRQs
  sh: sh7722 Enable SDIO IRQs
  sh: sh7724 Enable SDIO IRQs
  sh: Fix up legacy PTEA space attribute mapping.
  sh: Stub out legacy PCC pgprot encoding for X2 TLBs.
  sh: constify prefetch pointers.
  sh: Add a machvec callback for early memblock reservations.
  sh: update sh7757lcr_defconfig
  sh: add PVR probing for SH7757 3rd cut
  sh: Use device_initcall() instead of __initcall()
  sh: intc - convert board specific landisk code
  sh: Move init_landisk_IRQ to header file
  ...
2011-01-13 10:39:38 -08:00
Linus Torvalds
66dc918d42 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: (348 commits)
  ALSA: hda - Fix NULL-derefence with a single mic in STAC auto-mic detection
  ALSA: hda - Add missing NID 0x19 fixup for Sony VAIO
  ALSA: hda - Fix ALC275 enable hardware EQ for SONY VAIO
  ALSA: oxygen: fix Xonar DG input
  ALSA: hda - Fix EAPD on Lenovo NB ALC269 to low
  ALSA: hda - Fix missing EAPD for Acer 4930G
  ALSA: hda: Disable 4/6 channels on some NVIDIA GPUs.
  ALSA: hda - Add static_hdmi_pcm option to HDMI codec parser
  ALSA: hda - Don't refer ELD when unplugged
  ASoC: tpa6130a2: Fix compiler warning
  ASoC: tlv320dac33: Add DAPM selection for LOM invert
  ASoC: DMIC codec: Adding a generic DMIC codec
  ALSA: snd-usb-us122l: Fix missing NULL checks
  ALSA: snd-usb-us122l: Fix MIDI output
  ASoC: soc-cache: Fix invalid memory access during snd_soc_lzo_cache_sync()
  ASoC: Fix section mismatch in wm8995.c
  ALSA: oxygen: add S/PDIF source selection for Claro cards
  ALSA: oxygen: fix CD/MIDI for X-Meridian (2G)
  ASoC: fix migor audio build
  ALSA: include delay.h for msleep in Xonar DG support
  ...
2011-01-13 10:32:54 -08:00
Linus Torvalds
b2034d474b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (41 commits)
  fs: add documentation on fallocate hole punching
  Gfs2: fail if we try to use hole punch
  Btrfs: fail if we try to use hole punch
  Ext4: fail if we try to use hole punch
  Ocfs2: handle hole punching via fallocate properly
  XFS: handle hole punching via fallocate properly
  fs: add hole punching to fallocate
  vfs: pass struct file to do_truncate on O_TRUNC opens (try #2)
  fix signedness mess in rw_verify_area() on 64bit architectures
  fs: fix kernel-doc for dcache::prepend_path
  fs: fix kernel-doc for dcache::d_validate
  sanitize ecryptfs ->mount()
  switch afs
  move internal-only parts of ncpfs headers to fs/ncpfs
  switch ncpfs
  switch 9p
  pass default dentry_operations to mount_pseudo()
  switch hostfs
  switch affs
  switch configfs
  ...
2011-01-13 10:27:28 -08:00
Linus Torvalds
27d189c02b Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (46 commits)
  hwrng: via_rng - Fix memory scribbling on some CPUs
  crypto: padlock - Move padlock.h into include/crypto
  hwrng: via_rng - Fix asm constraints
  crypto: n2 - use __devexit not __exit in n2_unregister_algs
  crypto: mark crypto workqueues CPU_INTENSIVE
  crypto: mv_cesa - dont return PTR_ERR() of wrong pointer
  crypto: ripemd - Set module author and update email address
  crypto: omap-sham - backlog handling fix
  crypto: gf128mul - Remove experimental tag
  crypto: af_alg - fix af_alg memory_allocated data type
  crypto: aesni-intel - Fixed build with binutils 2.16
  crypto: af_alg - Make sure sk_security is initialized on accept()ed sockets
  net: Add missing lockdep class names for af_alg
  include: Install linux/if_alg.h for user-space crypto API
  crypto: omap-aes - checkpatch --file warning fixes
  crypto: omap-aes - initialize aes module once per request
  crypto: omap-aes - unnecessary code removed
  crypto: omap-aes - error handling implementation improved
  crypto: omap-aes - redundant locking is removed
  crypto: omap-aes - DMA initialization fixes for OMAP off mode
  ...
2011-01-13 10:25:58 -08:00
Linus Torvalds
a170315420 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  rbd: fix cleanup when trying to mount inexistent image
  net/ceph: make ceph_msgr_wq non-reentrant
  ceph: fsc->*_wq's aren't used in memory reclaim path
  ceph: Always free allocated memory in osdmap_decode()
  ceph: Makefile: Remove unnessary code
  ceph: associate requests with opening sessions
  ceph: drop redundant r_mds field
  ceph: implement DIRLAYOUTHASH feature to get dir layout from MDS
  ceph: add dir_layout to inode
2011-01-13 10:25:24 -08:00
Linus Torvalds
1896a1346a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6: (45 commits)
  regulator: missing index in PTR_ERR() in isl6271a_probe()
  regulator: Assign return value of mc13xxx_reg_rmw to ret
  regulator: Add initial per-regulator debugfs support
  regulator: Make regulator_has_full_constraints a bool
  regulator: Clean up logging a bit
  regulator: Optimise out noop voltage changes
  regulator: Add API to re-apply voltage to hardware
  regulator: Staticise non-exported functions in mc13892
  regulator: Only notify voltage changes when they succeed
  regulator: Provide a selector based set_voltage_sel() operation
  regulator: Factor out voltage set operation into a separate function
  regulator: Convert WM8994 to use get_voltage_sel()
  regulator: Convert WM835x to use get_voltage_sel()
  regulator: Allow modular build of mc13xxx-core
  regulator: support PMIC mc13892
  make mc13783 regulator code generic
  Change the register name definitions for mc13783
  mach-ux500: Updated and connected ab8500 regulator board configuration
  regulators: Removed macros for initialization of ab8500 regulators
  regulators: Added verbose debug messages to ab8500 regulators
  ...
2011-01-13 10:24:07 -08:00
Linus Torvalds
55065bc527 Merge branch 'kvm-updates/2.6.38' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.38' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (142 commits)
  KVM: Initialize fpu state in preemptible context
  KVM: VMX: when entering real mode align segment base to 16 bytes
  KVM: MMU: handle 'map_writable' in set_spte() function
  KVM: MMU: audit: allow audit more guests at the same time
  KVM: Fetch guest cr3 from hardware on demand
  KVM: Replace reads of vcpu->arch.cr3 by an accessor
  KVM: MMU: only write protect mappings at pagetable level
  KVM: VMX: Correct asm constraint in vmcs_load()/vmcs_clear()
  KVM: MMU: Initialize base_role for tdp mmus
  KVM: VMX: Optimize atomic EFER load
  KVM: VMX: Add definitions for more vm entry/exit control bits
  KVM: SVM: copy instruction bytes from VMCB
  KVM: SVM: implement enhanced INVLPG intercept
  KVM: SVM: enhance mov DR intercept handler
  KVM: SVM: enhance MOV CR intercept handler
  KVM: SVM: add new SVM feature bit names
  KVM: cleanup emulate_instruction
  KVM: move complete_insn_gp() into x86.c
  KVM: x86: fix CR8 handling
  KVM guest: Fix kvm clock initialization when it's configured out
  ...
2011-01-13 10:14:24 -08:00
Linus Torvalds
008d23e485 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (43 commits)
  Documentation/trace/events.txt: Remove obsolete sched_signal_send.
  writeback: fix global_dirty_limits comment runtime -> real-time
  ppc: fix comment typo singal -> signal
  drivers: fix comment typo diable -> disable.
  m68k: fix comment typo diable -> disable.
  wireless: comment typo fix diable -> disable.
  media: comment typo fix diable -> disable.
  remove doc for obsolete dynamic-printk kernel-parameter
  remove extraneous 'is' from Documentation/iostats.txt
  Fix spelling milisec -> ms in snd_ps3 module parameter description
  Fix spelling mistakes in comments
  Revert conflicting V4L changes
  i7core_edac: fix typos in comments
  mm/rmap.c: fix comment
  sound, ca0106: Fix assignment to 'channel'.
  hrtimer: fix a typo in comment
  init/Kconfig: fix typo
  anon_inodes: fix wrong function name in comment
  fix comment typos concerning "consistent"
  poll: fix a typo in comment
  ...

Fix up trivial conflicts in:
 - drivers/net/wireless/iwlwifi/iwl-core.c (moved to iwl-legacy.c)
 - fs/ext4/ext4.h

Also fix missed 'diabled' typo in drivers/net/bnx2x/bnx2x.h while at it.
2011-01-13 10:05:56 -08:00
Linus Torvalds
8f685fbda4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
  HID: hid-multitouch: minor fixes based on additional review
  HID: Switch turbox/mosart touchscreen to hid-mosart
  HID: add Add Cando touch screen 10.1-inch product id
  HID: hid-mulitouch: add support for the 'Sensing Win7-TwoFinger'
  HID: hid-multitouch: add support for Cypress TrueTouch panels
  HID: hid-multitouch: support for PixCir-based panels
  HID: set HID_MAX_FIELD at 128
  HID: add feature_mapping callback
2011-01-13 09:58:38 -08:00
Linus Torvalds
d24450e207 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: add SW_ROTATE_LOCK switch type
  Input: fix force feedback capability query example
  Input: wacom_w8001 - add single-touch support
  Input: add Austria Microsystem AS5011 joystick driver
  Input: remove aaed2000 keyboard driver
  Input: i8042 - introduce 'notimeout' blacklist for Dell Vostro V13
  Input: cy8ctmg110_ts - Convert to dev_pm_ops
  Input: migor_ts - convert to dev_pm_ops
  Input: mcs5000_ts - convert to dev_pm_ops
  Input: eeti_ts - convert to dev_pm_ops
  Input: ad7879 - convert I2C to dev_pm_ops
2011-01-13 09:58:14 -08:00
Lasse Collin
5cb2fad28f decompressors: remove unused constant from inflate.h
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:25 -08:00
Lasse Collin
3ebe12439b decompressors: add boot-time XZ support
This implements the API defined in <linux/decompress/generic.h> which is
used for kernel, initramfs, and initrd decompression.  This patch together
with the first patch is enough for XZ-compressed initramfs and initrd;
XZ-compressed kernel will need arch-specific changes.

The buffering requirements described in decompress_unxz.c are stricter
than with gzip, so the relevant changes should be done to the
arch-specific code when adding support for XZ-compressed kernel.
Similarly, the heap size in arch-specific pre-boot code may need to be
increased (30 KiB is enough).

The XZ decompressor needs memmove(), memeq() (memcmp() == 0), and
memzero() (memset(ptr, 0, size)), which aren't available in all
arch-specific pre-boot environments.  I'm including simple versions in
decompress_unxz.c, but a cleaner solution would naturally be nicer.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:25 -08:00
Lasse Collin
24fa0402a9 decompressors: add XZ decompressor module
In userspace, the .lzma format has become mostly a legacy file format that
got superseded by the .xz format.  Similarly, LZMA Utils was superseded by
XZ Utils.

These patches add support for XZ decompression into the kernel.  Most of
the code is as is from XZ Embedded <http://tukaani.org/xz/embedded.html>.
It was written for the Linux kernel but is usable in other projects too.

Advantages of XZ over the current LZMA code in the kernel:
  - Nice API that can be used by other kernel modules; it's
    not limited to kernel, initramfs, and initrd decompression.
  - Integrity check support (CRC32)
  - BCJ filters improve compression of executable code on
    certain architectures. These together with LZMA2 can
    produce a few percent smaller kernel or Squashfs images
    than plain LZMA without making the decompression slower.

This patch: Add the main decompression code (xz_dec), testing module
(xz_dec_test), wrapper script (xz_wrap.sh) for the xz command line tool,
and documentation.  The xz_dec module is enough to have a usable XZ
decompressor e.g.  for Squashfs.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:24 -08:00
Lasse Collin
2b6b5caa6d Decompressors: include <linux/slab.h> in <linux/decompress/mm.h>
Currently users of mm.h need to include <linux/slab.h> to use the macros
malloc() and free() provided by mm.h.  This fixes it.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:23 -08:00
Lasse Collin
93685ad247 Decompressors: get rid of set_error_fn() macro
set_error_fn() has become a useless complication after c1e7c3ae59
("bzip2/lzma/gzip: pre-boot malloc doesn't return NULL on failure") fixed
the use of error() in malloc().  Only decompress_unlzma.c had some use for
it and that was easy to change too.

This also gets rid of the static function pointer "error", which
should have been marked as __initdata.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:23 -08:00
Mike Frysinger
8d0a1decb4 romfs: have romfs_fs.h pull in necessary headers
This header uses things like __be32, so pull in linux/types.h.

Further, it uses BLOCK_SIZE, so pull in linux/fs.h.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:23 -08:00
Alexander Shishkin
beeae05138 cramfs: hide function prototypes behind __KERNEL__ macro
Currently, 3 kernel function prototypes are present in a header
file exported to userland. This patch fixes it.

Signed-off-by: Alexander Shishkin <virtuoso@slind.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:22 -08:00
Takashi Iwai
8930c8aa74 memstick: add support for JMicron JMB 385 and 390 controllers
Signed-off-by: Aries Lee <arieslee@jmicron.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: Alex Dubov <oakad@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:21 -08:00
Alexander Gordeev
717c033669 pps: add kernel consumer support
Add an optional feature of PPSAPI, kernel consumer support, which uses the
added hardpps() function.

Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:21 -08:00
Alexander Gordeev
e2c18e49a0 pps: capture MONOTONIC_RAW timestamps as well
MONOTONIC_RAW clock timestamps are ideally suited for frequency
calculation and also fit well into the original NTP hardpps design.  Now
phase and frequency can be adjusted separately: the former based on
REALTIME clock and the latter based on MONOTONIC_RAW clock.

A new function getnstime_raw_and_real is added to timekeeping subsystem to
capture both timestamps at the same time and atomically.

Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:21 -08:00
Alexander Gordeev
025b40abe7 ntp: add hardpps implementation
This commit adds hardpps() implementation based upon the original one from
the NTPv4 reference kernel code from David Mills.  However, it is highly
optimized towards very fast syncronization and maximum stickness to PPS
signal.  The typical error is less then a microsecond.

To make it sync faster I had to throw away exponential phase filter so
that the full phase offset is corrected immediately.  Then I also had to
throw away median phase filter because it gives a bigger error itself if
used without exponential filter.

Maybe we will find an appropriate filtering scheme in the future but it's
not necessary if the signal quality is ok.

Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:20 -08:00
Alexander Gordeev
12f9b1f9c1 pps: timestamp is always passed to dcd_change()
Remove the code that gatheres timestamp in pps_tty_dcd_change() in case
passed ts parameter is NULL because it never happens in the current code.
Fix comments as well.

Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:20 -08:00
Alexander Gordeev
5e196d34a7 pps: access pps device by direct pointer
Using device index as a pointer needs some unnecessary work to be done
every time the pointer is needed (in irq handler for example).  Using a
direct pointer is much more easy (and safe as well).

Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:19 -08:00
Alexander Gordeev
6f4229b511 pps: unify timestamp gathering
Add a helper function to gather timestamps.  This way clients don't have
to duplicate it.

Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:19 -08:00