lib/built-in.o:(__modver+0x8): undefined reference to `__modver_version_show'
lib/built-in.o:(__modver+0x2c): undefined reference to `__modver_version_show'
Simplest to just not emit anything: if they've disabled SYSFS they probably
want the smallest kernel possible.
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Currently only drivers that are built as modules have their versions
shown in /sys/module/<module_name>/version, but this information might
also be useful for built-in drivers as well. This especially important
for drivers that do not define any parameters - such drivers, if
built-in, are completely invisible from userspace.
This patch changes MODULE_VERSION() macro so that in case when we are
compiling built-in module, version information is stored in a separate
section. Kernel then uses this data to create 'version' sysfs attribute
in the same fashion it creates attributes for module parameters.
Signed-off-by: Dmitry Torokhov <dtor@vmware.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* 'for-usb-linus' of master.kernel.org:/pub/scm/linux/kernel/git/sarah/xhci:
xhci: Remove more doorbell-related reads
xHCI: fix printk_ratelimit() usage
xHCI: replace dev_dbg() with xhci_dbg()
xHCI: fix cycle bit set in giveback_first_trb()
xHCI: remove redundant parameter in giveback_first_trb()
xHCI: fix queue_trb in isoc transfer
xhci: Use GFP_NOIO during device reset.
usb: Realloc xHCI structures after a hub is verified.
xhci: Do not run xhci_cleanup_msix with irq disabled
xHCI: synchronize irq in xhci_suspend()
xhci: Resume bus on any port status change.
Alan's commit 335f8514f2 introduced
.carrier_raised function in several drivers. That also means
tty_port_block_til_ready can now suspend the process trying to open the serial
port when Carrier Detect is low and put it into tty_port.open_wait queue. We
need to wake up the process when Carrier Detect goes high and trigger TTY
hangup when CD goes low.
Some of the devices do not report modem status line changes, or at least we
don't understand the status message, so for those we remove .carrier_raised
again.
Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'media_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (101 commits)
[media] staging/lirc: fix mem leaks and ptr err usage
[media] hdpvr: reduce latency of i2c read/write w/recycled buffer
[media] hdpvr: enable IR part
[media] rc/mceusb: timeout should be in ns, not us
[media] v4l2-device: fix 'use-after-freed' oops
[media] v4l2-dev: don't memset video_device.dev
[media] zoran: use video_device_alloc instead of kmalloc
[media] w9966: zero device state after a detach
[media] v4l: Fix a use-before-set in the control framework
[media] v4l: Include linux/videodev2.h in media/v4l2-ctrls.h
[media] DocBook/v4l: update V4L2 revision and update copyright years
[media] DocBook/v4l: fix validation error in dev-rds.xml
[media] v4l2-ctrls: queryctrl shouldn't attempt to replace V4L2_CID_PRIVATE_BASE IDs
[media] v4l2-ctrls: fix missing 'read-only' check
[media] pvrusb2: Provide more information about IR units to lirc_zilog and ir-kbd-i2c
[media] ir-kbd-i2c: Add back defaults setting for Zilog Z8's at addr 0x71
[media] lirc_zilog: Update TODO.lirc_zilog
[media] lirc_zilog: Add Andy Walls to copyright notice and authors list
[media] lirc_zilog: Remove useless struct i2c_driver.command function
[media] lirc_zilog: Remove unneeded tests for existence of the IR Tx function
...
* 'fixes-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: note the nested NOT_RUNNING test in worker_clr_flags() isn't a noop
workqueue: relax lockdep annotation on flush_work()
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>
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>
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>
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>
In commit 44b8288308 (net_sched: pfifo_head_drop problem), we fixed
a problem with pfifo_head drops that incorrectly decreased
sch->bstats.bytes and sch->bstats.packets
Several qdiscs (CHOKe, SFQ, pfifo_head, ...) are able to drop a
previously enqueued packet, and bstats cannot be changed, so
bstats/rates are not accurate (over estimated)
This patch changes the qdisc_bstats updates to be done at dequeue() time
instead of enqueue() time. bstats counters no longer account for dropped
frames, and rates are more correct, since enqueue() bursts dont have
effect on dequeue() rate.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* '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
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>
* akpm:
kernel/smp.c: consolidate writes in smp_call_function_interrupt()
kernel/smp.c: fix smp_call_function_many() SMP race
memcg: correctly order reading PCG_USED and pc->mem_cgroup
backlight: fix 88pm860x_bl macro collision
drivers/leds/ledtrig-gpio.c: make output match input, tighten input checking
MAINTAINERS: update Atmel AT91 entry
mm: fix truncate_setsize() comment
memcg: fix rmdir, force_empty with THP
memcg: fix LRU accounting with THP
memcg: fix USED bit handling at uncharge in THP
memcg: modify accounting function for supporting THP better
fs/direct-io.c: don't try to allocate more than BIO_MAX_PAGES in a bio
mm: compaction: prevent division-by-zero during user-requested compaction
mm/vmscan.c: remove duplicate include of compaction.h
memblock: fix memblock_is_region_memory()
thp: keep highpte mapped until it is no longer needed
kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT
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>
* 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6:
ACPICA: Update version to 20110112
ACPICA: Update all ACPICA copyrights and signons to 2011
ACPICA: Fix issues/fault with automatic "serialized" method support
ACPICA: Debugger: Lock namespace for duration of a namespace dump
ACPICA: Fix namespace race condition
ACPICA: Fix memory leak in acpi_ev_asynch_execute_gpe_method().
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>
* 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
...
The option name of Delayed SACK Timer should be SCTP_DELAYED_SACK,
not SCTP_DELAYED_ACK.
Left SCTP_DELAYED_ACK be concomitant with SCTP_DELAYED_SACK,
for making compatibility with existing applications.
Reference:
8.1.19. Get or Set Delayed SACK Timer (SCTP_DELAYED_SACK)
（http://tools.ietf.org/html/draft-ietf-tsvwg-sctpsocket-25)
Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Acked-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The conn->sec_level value is supposed to represent the current level of
security that the connection has. However, by assigning to it before
requesting authentication it will have the wrong value during the
authentication procedure. To fix this a pending_sec_level variable is
added which is used to track the desired security level while making
sure that sec_level always represents the current level of security.
Signed-off-by: Johan Hedberg <johan.hedberg@nokia.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
The later makes extensive use of structures defined in the former.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The ene_ir driver was using a private define of MS_TO_NS, which is meant
to be microseconds to nanoseconds. The mceusb driver copied it,
intending to use is a milliseconds to microseconds. Lets move the
defines to a common location, expand and standardize them a touch, so
that we now have:
MS_TO_NS - milliseconds to nanoseconds
MS_TO_US - milliseconds to microseconds
US_TO_NS - microseconds to nanoseconds
Reported-by: David Härdeman <david@hardeman.nu>
CC: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Renamed has_new to is_new.
Drivers can use the is_new field to determine if a new value was specified
for a control. The v4l2_ctrl_handler_setup() must always set this to 1 since
the setup has to force a full update of all controls.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Some subdevs need to call into the board code after they are registered
and have a valid struct v4l2_device pointer. The s_config op was abused
for this, but now that it is removed we need a cleaner way of solving this.
So this patch adds a struct with internal ops that the v4l2 core can call.
Currently only two ops exist: register and unregister. Subdevs can implement
these to call the board code and pass it the v4l2_device pointer, which the
board code can then use to get access to the struct that embeds the
v4l2_device.
It is expected that in the future open and close ops will also be added.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The core.s_config op was meant for legacy drivers that needed to work with old
pre-2.6.26 kernels. This is no longer relevant. Unfortunately, this op was
incorrectly called from several drivers.
Replace those occurences with proper i2c_board_info structs and call
v4l2_i2c_new_subdev_board.
After these changes v4l2_i2c_new_subdev_cfg() was no longer used, so remove
that function as well.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Convert saa7146 to use core-assisted locking.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Version 20110112.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ALSA: hda - Fix initialization for HP 2011 notebooks
ALSA: hda - Add support for VMware controller
ALSA: hda - consitify string arrays
ALSA: hda - Add add multi-streaming playback for AD1988
ASoC: EP93xx: fixed LRCLK rate and DMA oper. in I2S code
ASoC: WM8990: msleep() takes milliseconds not jiffies
ALSA : au88x0 - Limit number of channels to fix Oops via OSS emu
ALSA: constify functions in ac97
ASoC: WL1273 FM radio: Fix breakage with MFD API changes
ALSA: hda - More coverage for odd-number channels elimination for HDMI
ALSA: hda - Store PCM parameters properly in HDMI open callback
ALSA: hda - Rearrange fixup struct in patch_realtek.c
ALSA: oxygen: Xonar DG: fix CS4245 register writes
ALSA: hda - Suppress the odd number of channels for HDMI
ALSA: hda - Add fixup-call in init callback
ALSA: hda - Reorganize fixup structure for Realtek
ALSA: hda - Apply Sony VAIO hweq fixup only once
ALSA: hda - Apply mario fixup only once
ALSA: hda - Remove unused fixup entry for ALC262
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>
* '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)
* '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
* 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.
* '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
* '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
...
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>
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>
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>
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>
* ib_wq is added, which is used as the common workqueue for infiniband
instead of the system workqueue. All system workqueue usages
including flush_scheduled_work() callers are converted to use and
flush ib_wq.
* cancel_delayed_work() + flush_scheduled_work() converted to
cancel_delayed_work_sync().
* qib_wq is removed and ib_wq is used instead.
This is to prepare for deprecation of flush_scheduled_work().
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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>
pmdp_get_and_clear/pmdp_clear_flush/pmdp_splitting_flush were trapped as
BUG() and they were defined only to diminish the risk of build issues on
not-x86 archs and to be consistent with the generic pte methods previously
defined in include/asm-generic/pgtable.h.
But they are causing more trouble than they were supposed to solve, so
it's simpler not to define them when THP is off.
This is also correcting the export of pmdp_splitting_flush which is
currently unused (x86 isn't using the generic implementation in
mm/pgtable-generic.c and no other arch needs that [yet]).
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Sam Ravnborg <sam@ravnborg.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
* '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
...
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>
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>
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>
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>
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>
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>
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>
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>
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>
* 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
Update Pekka's email address in MAINTAINERS
mm/slab.c: make local symbols static
slub: Avoid use of slub_lock in show_slab_objects()
memory hotplug: one more lock on memory hotplug
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
rcu: avoid pointless blocked-task warnings
rcu: demote SRCU_SYNCHRONIZE_DELAY from kernel-parameter status
rtmutex: Fix comment about why new_owner can be NULL in wake_futex_pi()
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, olpc: Add missing Kconfig dependencies
x86, mrst: Set correct APB timer IRQ affinity for secondary cpu
x86: tsc: Fix calibration refinement conditionals to avoid divide by zero
x86, ia64, acpi: Clean up x86-ism in drivers/acpi/numa.c
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
timekeeping: Make local variables static
time: Rename misnamed minsec argument of clocks_calc_mult_shift()
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing: Remove syscall_exit_fields
tracing: Only process module tracepoints once
perf record: Add "nodelay" mode, disabled by default
perf sched: Fix list of events, dropping unsupported ':r' modifier
Revert "perf tools: Emit clearer message for sys_perf_event_open ENOENT return"
perf top: Fix annotate segv
perf evsel: Fix order of event list deletion
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>
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>
This reverts commit dfe63bb0ad.
This commit was causing nouveau not to work properly, for -rc1 I'd
prefer it worked and we can look if this is useful for 2.6.39.
Cc: James Simmons <jsimmons@infradead.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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
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>
* '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
* 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
...
* '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.
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>
* '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)
* 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
...
* '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
* '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
...
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>
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>
The commit:
9f987b3141f086de27832514aad9f50a53f754
tracing: Include module.h in define_trace.h
only solved half the problem. If the trace/events/module.h header is
included at the time of define_trace.h (or in ftrace.h within it),
the module.h TRACE_SYSTEM will override the current TRACE_SYSTEM
macro.
Since define_trace.h is included when CREATE_TRACE_POINTS is set,
and the first thing it does is to #undef CREATE_TRACE_POINTS,
by placing the module.h TRACE_SYSTEM inside a
#ifdef CREATE_TRACE_POINTS
we can prevent it from overriding the TRACE_SYSTEM that is
being processed, and still process the module.h tracepoints
when the module code defines CREATE_TRACE_POINTS and includes
the trace/events/module.h header.
As with commit 9f987b3141, this is only an issue if module.h
is not included before the trace/events/<event>.h file is
included, which (luckily) has not happened yet.
Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
LIO target is a full featured in-kernel target framework with the
following feature set:
High-performance, non-blocking, multithreaded architecture with SIMD
support.
Advanced SCSI feature set:
* Persistent Reservations (PRs)
* Asymmetric Logical Unit Assignment (ALUA)
* Protocol and intra-nexus multiplexing, load-balancing and failover (MC/S)
* Full Error Recovery (ERL=0,1,2)
* Active/active task migration and session continuation (ERL=2)
* Thin LUN provisioning (UNMAP and WRITE_SAMExx)
Multiprotocol target plugins
Storage media independence:
* Virtualization of all storage media; transparent mapping of IO to LUNs
* No hard limits on number of LUNs per Target; maximum LUN size ~750 TB
* Backstores: SATA, SAS, SCSI, BluRay, DVD, FLASH, USB, ramdisk, etc.
Standards compliance:
* Full compliance with IETF (RFC 3720)
* Full implementation of SPC-4 PRs and ALUA
Significant code cleanups done by Christoph Hellwig.
[jejb: fix up for new block bdev exclusive interface. Minor fixes from
Randy Dunlap and Dan Carpenter.]
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
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>
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>
__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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
icv_truncbits is set to 256 for sha512, so update
MAX_AH_AUTH_LEN to 64.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
* '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
...
* '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
* '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
* 'stable/gntdev' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/p2m: Fix module linking error.
xen p2m: clear the old pte when adding a page to m2p_override
xen gntdev: use gnttab_map_refs and gnttab_unmap_refs
xen: introduce gnttab_map_refs and gnttab_unmap_refs
xen p2m: transparently change the p2m mappings in the m2p override
xen/gntdev: Fix circular locking dependency
xen/gntdev: stop using "token" argument
xen: gntdev: move use of GNTMAP_contains_pte next to the map_op
xen: add m2p override mechanism
xen: move p2m handling to separate file
xen/gntdev: add VM_PFNMAP to vma
xen/gntdev: allow usermode to map granted pages
xen: define gnttab_set_map_op/unmap_op
Fix up trivial conflict in drivers/xen/Kconfig
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Some are needed to build but not actually used on archs not supporting
transparent hugepages. Others like pmdp_clear_flush are used by x86 too.
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>
These returns 0 at compile time when the config option is disabled, to
allow gcc to eliminate the transparent hugepage function calls at compile
time without additional #ifdefs (only the export of those functions have
to be visible to gcc but they won't be required at link time and
huge_memory.o can be not built at all).
_PAGE_BIT_UNUSED1 is never used for pmd, only on pte.
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
With compaction being used instead of lumpy reclaim, the name lumpy_mode
and associated variables is a bit misleading. Rename lumpy_mode to
reclaim_mode which is a better fit. There is no functional change.
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>
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>
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>
