This patch adds a backlight driver for controlling the pcf50633 LED module.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
This is S6E63M0 AMOLED LCD Panel(480x800) driver using 3-wired SPI
interface also almost features for lcd panel driver has been implemented
in here. and I added new structure common for all the lcd panel drivers
to include/linux/lcd.h file.
LCD Panel driver needs interfaces for controlling device power such as
power on/off and reset. these interfaces are device specific so it should
be implemented to machine code at this time, we should create new
structure for registering these functions as callbacks and also a header
file for that structure and finally registered callback functions would be
called by lcd panel driver. such header file(including new structure for
lcd panel) would be added for all the lcd panel drivers.
If anyone provides common structure for registering such callback
functions then we could reduce unnecessary header files for lcd panel. I
thought that suitable anyone could be include/linux/lcd.h so a new
lcd_platform_data structure was added there.
[akpm@linux-foundation.org: coding-style fixes]
[randy.dunlap@oracle.com: fix s6e63m0 kconfig]
[randy.dunlap@oracle.com: fix device attribute functions return types]
Signed-off-by: InKi Dae <inki.dae@samsung.com>
Reviewed-by: KyungMin Park <kyungmin.park.samsung.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
The ADP8860 combines a programmable backlight LED charge pump driver with
automatic phototransistor control.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (63 commits)
drivers/net/usb/asix.c: Fix pointer cast.
be2net: Bug fix to avoid disabling bottom half during firmware upgrade.
proc_dointvec: write a single value
hso: add support for new products
Phonet: fix potential use-after-free in pep_sock_close()
ath9k: remove VEOL support for ad-hoc
ath9k: change beacon allocation to prefer the first beacon slot
sock.h: fix kernel-doc warning
cls_cgroup: Fix build error when built-in
macvlan: do proper cleanup in macvlan_common_newlink() V2
be2net: Bug fix in init code in probe
net/dccp: expansion of error code size
ath9k: Fix rx of mcast/bcast frames in PS mode with auto sleep
wireless: fix sta_info.h kernel-doc warnings
wireless: fix mac80211.h kernel-doc warnings
iwlwifi: testing the wrong variable in iwl_add_bssid_station()
ath9k_htc: rare leak in ath9k_hif_usb_alloc_tx_urbs()
ath9k_htc: dereferencing before check in hif_usb_tx_cb()
rt2x00: Fix rt2800usb TX descriptor writing.
rt2x00: Fix failed SLEEP->AWAKE and AWAKE->SLEEP transitions.
...
This adds:
alias: devname:<name>
to some common kernel modules, which will allow the on-demand loading
of the kernel module when the device node is accessed.
Ideally all these modules would be compiled-in, but distros seems too
much in love with their modularization that we need to cover the common
cases with this new facility. It will allow us to remove a bunch of pretty
useless init scripts and modprobes from init scripts.
The static device node aliases will be carried in the module itself. The
program depmod will extract this information to a file in the module directory:
$ cat /lib/modules/2.6.34-00650-g537b60d-dirty/modules.devname
# Device nodes to trigger on-demand module loading.
microcode cpu/microcode c10:184
fuse fuse c10:229
ppp_generic ppp c108:0
tun net/tun c10:200
dm_mod mapper/control c10:235
Udev will pick up the depmod created file on startup and create all the
static device nodes which the kernel modules specify, so that these modules
get automatically loaded when the device node is accessed:
$ /sbin/udevd --debug
...
static_dev_create_from_modules: mknod '/dev/cpu/microcode' c10:184
static_dev_create_from_modules: mknod '/dev/fuse' c10:229
static_dev_create_from_modules: mknod '/dev/ppp' c108:0
static_dev_create_from_modules: mknod '/dev/net/tun' c10:200
static_dev_create_from_modules: mknod '/dev/mapper/control' c10:235
udev_rules_apply_static_dev_perms: chmod '/dev/net/tun' 0666
udev_rules_apply_static_dev_perms: chmod '/dev/fuse' 0666
A few device nodes are switched to statically allocated numbers, to allow
the static nodes to work. This might also useful for systems which still run
a plain static /dev, which is completely unsafe to use with any dynamic minor
numbers.
Note:
The devname aliases must be limited to the *common* and *single*instance*
device nodes, like the misc devices, and never be used for conceptually limited
systems like the loop devices, which should rather get fixed properly and get a
control node for losetup to talk to, instead of creating a random number of
device nodes in advance, regardless if they are ever used.
This facility is to hide the mess distros are creating with too modualized
kernels, and just to hide that these modules are not compiled-in, and not to
paper-over broken concepts. Thanks! :)
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: Ian Kent <raven@themaw.net>
Signed-Off-By: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
RDMA/nes: Fix incorrect unlock in nes_process_mac_intr()
RDMA/nes: Async event for closed QP causes crash
RDMA/nes: Have ethtool read hardware registers for rx/tx stats
RDMA/cxgb4: Only insert sq qid in lookup table
RDMA/cxgb4: Support IB_WR_READ_WITH_INV opcode
RDMA/cxgb4: Set fence flag for inv-local-stag work requests
RDMA/cxgb4: Update some HW limits
RDMA/cxgb4: Don't limit fastreg page list depth
RDMA/cxgb4: Return proper errors in fastreg mr/pbl allocation
RDMA/cxgb4: Fix overflow bug in CQ arm
RDMA/cxgb4: Optimize CQ overflow detection
RDMA/cxgb4: CQ size must be IQ size - 2
RDMA/cxgb4: Register RDMA provider based on LLD state_change events
RDMA/cxgb4: Detach from the LLD after unregistering RDMA device
IB/ipath: Remove support for QLogic PCIe QLE devices
IB/qib: Add new qib driver for QLogic PCIe InfiniBand adapters
IB/mad: Make needlessly global mad_sendq_size/mad_recvq_size static
IB/core: Allow device-specific per-port sysfs files
mlx4_core: Clean up mlx4_alloc_icm() a bit
mlx4_core: Fix possible chunk sg list overflow in mlx4_alloc_icm()
* 'next-spi' of git://git.secretlab.ca/git/linux-2.6:
spi/xilinx: Fix compile error
spi/davinci: Fix clock prescale factor computation
spi: move bitbang txrx utility functions to private header
spi/mpc5121: Add SPI master driver for MPC5121 PSC
powerpc/mpc5121: move PSC FIFO memory init to platform code
spi/ep93xx: implemented driver for Cirrus EP93xx SPI controller
Documentation/spi/* compile warning fix
spi/omap2_mcspi: Check params before dereference or use
spi/omap2_mcspi: add turbo mode support
spi/omap2_mcspi: change default DMA_MIN_BYTES value to 160
spi/pl022: fix stop queue procedure
spi/pl022: add support for the PL023 derivate
spi/pl022: fix up differences between ARM and ST versions
spi/spi_mpc8xxx: Do not use map_tx_dma to unmap rx_dma
spi/spi_mpc8xxx: Fix QE mode Litte Endian
spi/spi_mpc8xxx: fix potential memory corruption.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6:
regulator: return set_mode is same mode is requested
Regulators: ab3100/bq24022: add a missing .owner field in regulator_desc
twl6030: regulator: Remove vsel tables and use formula for calculation
mc13783-regulator: fix vaild voltage range checking for mc13783_fixed_regulator_set_voltage
regulator: use voltage number array in 88pm860x
regulator: make 88pm860x sharing one driver structure
regulator: simplify regulator_register() error handling
regulator: fix unset_regulator_supplies() to remove all matches
regulator: prevent registration of matching regulator consumer supplies
regulator: Allow regulator-regulator supplies to be specified by name
FBIO_WAITFORVSYNC is currently implemented by matroxfb, atyfb, intelfb and
more. All of them keep redefining the same FBIO_WAITFORVSYNC macro over
and over again, so move it to linux/fb.h and clean up those duplicate
defines.
Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Cc: Ville Syrjala <syrjala@sci.fi>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Maik Broemme <mbroemme@plusserver.de>
Cc: Petr Vandrovec <vandrove@vc.cvut.cz>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Cc: "Hiremath, Vaibhav" <hvaibhav@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This work includes the following:
- Implement handler for FBIO_WAITFORVSYNC ioctl.
- Allocate the data and palette buffers separately. A consequence of
this is that the palette and data loading is now done in different
phases. And that the LCD must be disabled temporarily after the palette
is loaded but this will only happen once after init and each time the
palette is changed. I think this is OK.
- Allocate two (ping and pong) framebuffers from memory.
- Add pan_display handler which toggles the LCDC DMA registers between
the ping and pong buffers.
Signed-off-by: Martin Ambrose <martin@ti.com>
Cc: Chaithrika U S <chaithrika@ti.com>
Cc: Sudhakar Rajashekhara <sudhakar.raj@ti.com>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Content for the 8bit device threaded interrupt handlers. Depending on the
interrupt line and chip configuration, either click or wakeup / freefall
handler is called. In case of click, BTN_ event is sent via input device.
In case of wakeup or freefall, input device ABS_ events are updated
immediatelly.
It is still possible to configure interrupt line 1 for fast freefall
detection and use the second line either for click or threshold based
interrupts. Or both lines can be used for click / threshold interrupts.
Polled input device can be set to stopped state and still get coordinate
updates via input device using interrupt based method. Polled mode and
interrupt mode can also be used parallel.
BTN_ events are remapped based on existing axis remapping information.
Signed-off-by: Samu Onkalo <samu.p.onkalo@nokia.com>
Acked-by: Eric Piel <eric.piel@tremplin-utc.net>
Cc: Daniel Mack <daniel@caiaq.de>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Original lis3 driver didn't provide interrupt handler(s) for click or
threshold event handling. This patch adds threaded handlers for one or
two interrupt lines for 8 bit device. Actual content for interrupt
handling is provided in the separate patch.
Signed-off-by: Samu Onkalo <samu.p.onkalo@nokia.com>
Tested-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Eric Piel <eric.piel@tremplin-utc.net>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 bit device has two wakeup / free fall units. It was not possible to
configure the second unit. This patch introduces configuration entry to
the platform data and also corresponding changes to the 8 bit setup
function.
High pass filters were enabled by default. Patch introduces configuration
option for high pass filter cut off frequency and also possibility to
disable or enable the filter via platform data. Since the control is a
new one and default state was filter enabled, new option is used to
disable the filter. This way old platform data is still compatible with
the change.
Signed-off-by: Samu Onkalo <samu.p.onkalo@nokia.com>
Acked-by: Eric Piel <eric.piel@tremplin-utc.net>
Tested-by: Daniel Mack <daniel@caiaq.de>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hex_to_bin() is a little method which converts hex digit to its actual
value. There are plenty of places where such functionality is needed.
[akpm@linux-foundation.org: use tolower(), saving 3 bytes, test the more common case first - it's quicker]
[akpm@linux-foundation.org: relocate tolower to make it even faster! (Joe)]
Signed-off-by: Andy Shevchenko <ext-andriy.shevchenko@nokia.com>
Cc: Tilman Schmidt <tilman@imap.cc>
Cc: Duncan Sands <duncan.sands@free.fr>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: "Richard Russon (FlatCap)" <ldm@flatcap.org>
Cc: John W. Linville <linville@tuxdriver.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For now, all users of ratelimit_state allocates it statically, so
DEFINE_RATELIMIT_STATE() is enough. But, I want to use ratelimit_state
for fs, i.e. per super_block to suppress too many error reports.
So, this adds ratelimit_state_init() to initialize ratelimite_state
which is dynamically allocated, instead of opencoding.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ratelimit_state initialization of printk_ratelimited() seems broken. This
fixes it by using DEFINE_RATELIMIT_STATE() to initialize spinlock
properly.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
32-bit Sparc used to only allow usage of 24-bit of it's atomic_t type.
This was corrected with linux 2.6.3 when Keith M Wesolowski changed the
implementation to use the parisc approach of having an array of spinlocks
to protect the atomic_t.
These warnings were also removed from the sparc implementation when the
new implementation was merged in BKrev:402e4949VThdc6D3iaosSFUgabMfvw, but
the warning still remained in some other places without any 24-bit-only
atomic_t implementation inside the kernel.
We should remove these warnings to allow users to rely on the full 32-bit
range of atomic_t.
Signed-off-by: Peter Fritzsche <peter.fritzsche@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- C99 knows about USHRT_MAX/SHRT_MAX/SHRT_MIN, not
USHORT_MAX/SHORT_MAX/SHORT_MIN.
- Make SHRT_MIN of type s16, not int, for consistency.
[akpm@linux-foundation.org: fix drivers/dma/timb_dma.c]
[akpm@linux-foundation.org: fix security/keys/keyring.c]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linux does not define __BYTE_ORDER in its endian header files which makes
some header files bend backwards to get at the current endian. Lets
#define __BYTE_ORDER in big_endian.h/litte_endian.h to make it easier for
header files that are used in user space too.
In userspace the convention is that
1. _both_ __LITTLE_ENDIAN and __BIG_ENDIAN are defined,
2. you have to test for e.g. __BYTE_ORDER == __BIG_ENDIAN.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add __must_check to error pointer handlers to have the compiler warn about
mistakes like:
if (err)
ERR_PTR(err);
It found two bugs:
Mar 12 Nikula Jani [PATCH] enclosure: fix error path - actually return ERR_PTR() on error
Mar 12 Nikula Jani [PATCH] sunrpc: fix error path - actually return ERR_PTR() on error
Signed-off-by: Jani Nikula <ext-jani.1.nikula@nokia.com>
Cc: Phil Carmody <ext-phil.2.carmody@nokia.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This ensures that platforms with lowmem PAs above 32 bits work correctly
by avoiding truncating the PA during a left shift.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add global mutex zonelists_mutex to fix the possible race:
CPU0 CPU1 CPU2
(1) zone->present_pages += online_pages;
(2) build_all_zonelists();
(3) alloc_page();
(4) free_page();
(5) build_all_zonelists();
(6) __build_all_zonelists();
(7) zone->pageset = alloc_percpu();
In step (3,4), zone->pageset still points to boot_pageset, so bad
things may happen if 2+ nodes are in this state. Even if only 1 node
is accessing the boot_pageset, (3) may still consume too much memory
to fail the memory allocations in step (7).
Besides, atomic operation ensures alloc_percpu() in step (7) will never fail
since there is a new fresh memory block added in step(6).
[haicheng.li@linux.intel.com: hold zonelists_mutex when build_all_zonelists]
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Reviewed-by: Andi Kleen <andi.kleen@intel.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For each new populated zone of hotadded node, need to update its pagesets
with dynamically allocated per_cpu_pageset struct for all possible CPUs:
1) Detach zone->pageset from the shared boot_pageset
at end of __build_all_zonelists().
2) Use mutex to protect zone->pageset when it's still
shared in onlined_pages()
Otherwises, multiple zones of different nodes would share same boot strapping
boot_pageset for same CPU, which will finally cause below kernel panic:
------------[ cut here ]------------
kernel BUG at mm/page_alloc.c:1239!
invalid opcode: 0000 [#1] SMP
...
Call Trace:
[<ffffffff811300c1>] __alloc_pages_nodemask+0x131/0x7b0
[<ffffffff81162e67>] alloc_pages_current+0x87/0xd0
[<ffffffff81128407>] __page_cache_alloc+0x67/0x70
[<ffffffff811325f0>] __do_page_cache_readahead+0x120/0x260
[<ffffffff81132751>] ra_submit+0x21/0x30
[<ffffffff811329c6>] ondemand_readahead+0x166/0x2c0
[<ffffffff81132ba0>] page_cache_async_readahead+0x80/0xa0
[<ffffffff8112a0e4>] generic_file_aio_read+0x364/0x670
[<ffffffff81266cfa>] nfs_file_read+0xca/0x130
[<ffffffff8117b20a>] do_sync_read+0xfa/0x140
[<ffffffff8117bf75>] vfs_read+0xb5/0x1a0
[<ffffffff8117c151>] sys_read+0x51/0x80
[<ffffffff8103c032>] system_call_fastpath+0x16/0x1b
RIP [<ffffffff8112ff13>] get_page_from_freelist+0x883/0x900
RSP <ffff88000d1e78a8>
---[ end trace 4bda28328b9990db ]
[akpm@linux-foundation.org: merge fix]
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Reviewed-by: Andi Kleen <andi.kleen@intel.com>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Got this while compiling for ARM/SA1100:
mm/sparse.c: In function '__section_nr':
mm/sparse.c:135: warning: 'root' is used uninitialized in this function
This patch follows Russell King's suggestion for a new calculation for
NR_SECTION_ROOTS. Thanks also to Sergei Shtylyov for pointing out the
existence of the macro DIV_ROUND_UP.
Atsushi Nemoto observed:
: This fix doesn't just silence the warning - it fixes a real problem.
:
: Without this fix, mem_section[] might have 0 size so mem_section[0]
: will share other variable area. For example, I got:
:
: c030c700 b __warned.16478
: c030c700 B mem_section
: c030c701 b __warned.16483
:
: This might cause very strange behavior. Your patch actually fixes it.
Signed-off-by: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br>
Cc: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Sergei Shtylyov <sshtylyov@mvista.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In f4112de6b6 ("mm: introduce
debug_kmap_atomic") I said that debug_kmap_atomic() needs
CONFIG_TRACE_IRQFLAGS_SUPPORT.
It was wrong. (I thought irqs_disabled() is only available when the
architecture has CONFIG_TRACE_IRQFLAGS_SUPPORT)
Remove the #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT check to enable
kmap_atomic() debugging for the architectures which do not have
CONFIG_TRACE_IRQFLAGS_SUPPORT.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add parenthesis in a define. This doesn't change functionality.
checkpatch errors:
1) white space fixes
2) add spaces after comas
Signed-off-by: matt mooney <mfm@muteddisk.com>
Cc: Dan Carpenter <error27@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix minor spelling errors in a few comments; no code changes.
Signed-off-by: matt mooney <mfm@muteddisk.com>
Cc: Dan Carpenter <error27@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Enable users to online CPUs even if the CPUs belongs to a numa node which
doesn't have onlined local memory.
The zonlists(pg_data_t.node_zonelists[]) of a numa node are created either
in system boot/init period, or at the time of local memory online. For a
numa node without onlined local memory, its zonelists are not initialized
at present. As a result, any memory allocation operations executed by
CPUs within this node will fail. In fact, an out-of-memory error is
triggered when attempt to online CPUs before memory comes to online.
This patch tries to create zonelists for such numa nodes, so that the
memory allocation for this node can be fallback'ed to other nodes.
[akpm@linux-foundation.org: remove unneeded export]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: minskey guo<chaohong.guo@intel.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For now, we have global isolation vs. memory control group isolation, do
not allow the reclaim entry function to set an arbitrary page isolation
callback, we do not need that flexibility.
And since we already pass around the group descriptor for the memory
control group isolation case, just use it to decide which one of the two
isolator functions to use.
The decisions can be merged into nearby branches, so no extra cost there.
In fact, we save the indirect calls.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
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>
The fragmentation index may indicate that a failure is due to external
fragmentation but after a compaction run completes, it is still possible
for an allocation to fail. There are two obvious reasons as to why
o Page migration cannot move all pages so fragmentation remains
o A suitable page may exist but watermarks are not met
In the event of compaction followed by an allocation failure, this patch
defers further compaction in the zone (1 << compact_defer_shift) times.
If the next compaction attempt also fails, compact_defer_shift is
increased up to a maximum of 6. If compaction succeeds, the defer
counters are reset again.
The zone that is deferred is the first zone in the zonelist - i.e. the
preferred zone. To defer compaction in the other zones, the information
would need to be stored in the zonelist or implemented similar to the
zonelist_cache. This would impact the fast-paths and is not justified at
this time.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kernel applies some heuristics when deciding if memory should be
compacted or reclaimed to satisfy a high-order allocation. One of these
is based on the fragmentation. If the index is below 500, memory will not
be compacted. This choice is arbitrary and not based on data. To help
optimise the system and set a sensible default for this value, this patch
adds a sysctl extfrag_threshold. The kernel will only compact memory if
the fragmentation index is above the extfrag_threshold.
[randy.dunlap@oracle.com: Fix build errors when proc fs is not configured]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ordinarily when a high-order allocation fails, direct reclaim is entered
to free pages to satisfy the allocation. With this patch, it is
determined if an allocation failed due to external fragmentation instead
of low memory and if so, the calling process will compact until a suitable
page is freed. Compaction by moving pages in memory is considerably
cheaper than paging out to disk and works where there are locked pages or
no swap. If compaction fails to free a page of a suitable size, then
reclaim will still occur.
Direct compaction returns as soon as possible. As each block is
compacted, it is checked if a suitable page has been freed and if so, it
returns.
[akpm@linux-foundation.org: Fix build errors]
[aarcange@redhat.com: fix count_vm_event preempt in memory compaction direct reclaim]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.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>
Add a per-node sysfs file called compact. When the file is written to,
each zone in that node is compacted. The intention that this would be
used by something like a job scheduler in a batch system before a job
starts so that the job can allocate the maximum number of hugepages
without significant start-up cost.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a proc file /proc/sys/vm/compact_memory. When an arbitrary value is
written to the file, all zones are compacted. The expected user of such a
trigger is a job scheduler that prepares the system before the target
application runs.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch is the core of a mechanism which compacts memory in a zone by
relocating movable pages towards the end of the zone.
A single compaction run involves a migration scanner and a free scanner.
Both scanners operate on pageblock-sized areas in the zone. The migration
scanner starts at the bottom of the zone and searches for all movable
pages within each area, isolating them onto a private list called
migratelist. The free scanner starts at the top of the zone and searches
for suitable areas and consumes the free pages within making them
available for the migration scanner. The pages isolated for migration are
then migrated to the newly isolated free pages.
[aarcange@redhat.com: Fix unsafe optimisation]
[mel@csn.ul.ie: do not schedule work on other CPUs for compaction]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Page migration requires rmap to be able to find all ptes mapping a page
at all times, otherwise the migration entry can be instantiated, but it
is possible to leave one behind if the second rmap_walk fails to find
the page. If this page is later faulted, migration_entry_to_page() will
call BUG because the page is locked indicating the page was migrated by
the migration PTE not cleaned up. For example
kernel BUG at include/linux/swapops.h:105!
invalid opcode: 0000 [#1] PREEMPT SMP
...
Call Trace:
[<ffffffff810e951a>] handle_mm_fault+0x3f8/0x76a
[<ffffffff8130c7a2>] do_page_fault+0x44a/0x46e
[<ffffffff813099b5>] page_fault+0x25/0x30
[<ffffffff8114de33>] load_elf_binary+0x152a/0x192b
[<ffffffff8111329b>] search_binary_handler+0x173/0x313
[<ffffffff81114896>] do_execve+0x219/0x30a
[<ffffffff8100a5c6>] sys_execve+0x43/0x5e
[<ffffffff8100320a>] stub_execve+0x6a/0xc0
RIP [<ffffffff811094ff>] migration_entry_wait+0xc1/0x129
There is a race between shift_arg_pages and migration that triggers this
bug. A temporary stack is setup during exec and later moved. If
migration moves a page in the temporary stack and the VMA is then removed
before migration completes, the migration PTE may not be found leading to
a BUG when the stack is faulted.
This patch causes pages within the temporary stack during exec to be
skipped by migration. It does this by marking the VMA covering the
temporary stack with an otherwise impossible combination of VMA flags.
These flags are cleared when the temporary stack is moved to its final
location.
[kamezawa.hiroyu@jp.fujitsu.com: idea for having migration skip temporary stacks]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For clarity of review, KSM and page migration have separate refcounts on
the anon_vma. While clear, this is a waste of memory. This patch gets
KSM and page migration to share their toys in a spirit of harmony.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
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>
This patchset is a memory compaction mechanism that reduces external
fragmentation memory by moving GFP_MOVABLE pages to a fewer number of
pageblocks. The term "compaction" was chosen as there are is a number of
mechanisms that are not mutually exclusive that can be used to defragment
memory. For example, lumpy reclaim is a form of defragmentation as was
slub "defragmentation" (really a form of targeted reclaim). Hence, this
is called "compaction" to distinguish it from other forms of
defragmentation.
In this implementation, a full compaction run involves two scanners
operating within a zone - a migration and a free scanner. The migration
scanner starts at the beginning of a zone and finds all movable pages
within one pageblock_nr_pages-sized area and isolates them on a
migratepages list. The free scanner begins at the end of the zone and
searches on a per-area basis for enough free pages to migrate all the
pages on the migratepages list. As each area is respectively migrated or
exhausted of free pages, the scanners are advanced one area. A compaction
run completes within a zone when the two scanners meet.
This method is a bit primitive but is easy to understand and greater
sophistication would require maintenance of counters on a per-pageblock
basis. This would have a big impact on allocator fast-paths to improve
compaction which is a poor trade-off.
It also does not try relocate virtually contiguous pages to be physically
contiguous. However, assuming transparent hugepages were in use, a
hypothetical khugepaged might reuse compaction code to isolate free pages,
split them and relocate userspace pages for promotion.
Memory compaction can be triggered in one of three ways. It may be
triggered explicitly by writing any value to /proc/sys/vm/compact_memory
and compacting all of memory. It can be triggered on a per-node basis by
writing any value to /sys/devices/system/node/nodeN/compact where N is the
node ID to be compacted. When a process fails to allocate a high-order
page, it may compact memory in an attempt to satisfy the allocation
instead of entering direct reclaim. Explicit compaction does not finish
until the two scanners meet and direct compaction ends if a suitable page
becomes available that would meet watermarks.
The series is in 14 patches. The first three are not "core" to the series
but are important pre-requisites.
Patch 1 reference counts anon_vma for rmap_walk_anon(). Without this
patch, it's possible to use anon_vma after free if the caller is
not holding a VMA or mmap_sem for the pages in question. While
there should be no existing user that causes this problem,
it's a requirement for memory compaction to be stable. The patch
is at the start of the series for bisection reasons.
Patch 2 merges the KSM and migrate counts. It could be merged with patch 1
but would be slightly harder to review.
Patch 3 skips over unmapped anon pages during migration as there are no
guarantees about the anon_vma existing. There is a window between
when a page was isolated and migration started during which anon_vma
could disappear.
Patch 4 notes that PageSwapCache pages can still be migrated even if they
are unmapped.
Patch 5 allows CONFIG_MIGRATION to be set without CONFIG_NUMA
Patch 6 exports a "unusable free space index" via debugfs. It's
a measure of external fragmentation that takes the size of the
allocation request into account. It can also be calculated from
userspace so can be dropped if requested
Patch 7 exports a "fragmentation index" which only has meaning when an
allocation request fails. It determines if an allocation failure
would be due to a lack of memory or external fragmentation.
Patch 8 moves the definition for LRU isolation modes for use by compaction
Patch 9 is the compaction mechanism although it's unreachable at this point
Patch 10 adds a means of compacting all of memory with a proc trgger
Patch 11 adds a means of compacting a specific node with a sysfs trigger
Patch 12 adds "direct compaction" before "direct reclaim" if it is
determined there is a good chance of success.
Patch 13 adds a sysctl that allows tuning of the threshold at which the
kernel will compact or direct reclaim
Patch 14 temporarily disables compaction if an allocation failure occurs
after compaction.
Testing of compaction was in three stages. For the test, debugging,
preempt, the sleep watchdog and lockdep were all enabled but nothing nasty
popped out. min_free_kbytes was tuned as recommended by hugeadm to help
fragmentation avoidance and high-order allocations. It was tested on X86,
X86-64 and PPC64.
Ths first test represents one of the easiest cases that can be faced for
lumpy reclaim or memory compaction.
1. Machine freshly booted and configured for hugepage usage with
a) hugeadm --create-global-mounts
b) hugeadm --pool-pages-max DEFAULT:8G
c) hugeadm --set-recommended-min_free_kbytes
d) hugeadm --set-recommended-shmmax
The min_free_kbytes here is important. Anti-fragmentation works best
when pageblocks don't mix. hugeadm knows how to calculate a value that
will significantly reduce the worst of external-fragmentation-related
events as reported by the mm_page_alloc_extfrag tracepoint.
2. Load up memory
a) Start updatedb
b) Create in parallel a X files of pagesize*128 in size. Wait
until files are created. By parallel, I mean that 4096 instances
of dd were launched, one after the other using &. The crude
objective being to mix filesystem metadata allocations with
the buffer cache.
c) Delete every second file so that pageblocks are likely to
have holes
d) kill updatedb if it's still running
At this point, the system is quiet, memory is full but it's full with
clean filesystem metadata and clean buffer cache that is unmapped.
This is readily migrated or discarded so you'd expect lumpy reclaim
to have no significant advantage over compaction but this is at
the POC stage.
3. In increments, attempt to allocate 5% of memory as hugepages.
Measure how long it took, how successful it was, how many
direct reclaims took place and how how many compactions. Note
the compaction figures might not fully add up as compactions
can take place for orders other than the hugepage size
X86 vanilla compaction
Final page count 913 916 (attempted 1002)
pages reclaimed 68296 9791
X86-64 vanilla compaction
Final page count: 901 902 (attempted 1002)
Total pages reclaimed: 112599 53234
PPC64 vanilla compaction
Final page count: 93 94 (attempted 110)
Total pages reclaimed: 103216 61838
There was not a dramatic improvement in success rates but it wouldn't be
expected in this case either. What was important is that fewer pages were
reclaimed in all cases reducing the amount of IO required to satisfy a
huge page allocation.
The second tests were all performance related - kernbench, netperf, iozone
and sysbench. None showed anything too remarkable.
The last test was a high-order allocation stress test. Many kernel
compiles are started to fill memory with a pressured mix of unmovable and
movable allocations. During this, an attempt is made to allocate 90% of
memory as huge pages - one at a time with small delays between attempts to
avoid flooding the IO queue.
vanilla compaction
Percentage of request allocated X86 98 99
Percentage of request allocated X86-64 95 98
Percentage of request allocated PPC64 55 70
This patch:
rmap_walk_anon() does not use page_lock_anon_vma() for looking up and
locking an anon_vma and it does not appear to have sufficient locking to
ensure the anon_vma does not disappear from under it.
This patch copies an approach used by KSM to take a reference on the
anon_vma while pages are being migrated. This should prevent rmap_walk()
running into nasty surprises later because anon_vma has been freed.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Before applying this patch, cpuset updates task->mems_allowed and
mempolicy by setting all new bits in the nodemask first, and clearing all
old unallowed bits later. But in the way, the allocator may find that
there is no node to alloc memory.
The reason is that cpuset rebinds the task's mempolicy, it cleans the
nodes which the allocater can alloc pages on, for example:
(mpol: mempolicy)
task1 task1's mpol task2
alloc page 1
alloc on node0? NO 1
1 change mems from 1 to 0
1 rebind task1's mpol
0-1 set new bits
0 clear disallowed bits
alloc on node1? NO 0
...
can't alloc page
goto oom
This patch fixes this problem by expanding the nodes range first(set newly
allowed bits) and shrink it lazily(clear newly disallowed bits). So we
use a variable to tell the write-side task that read-side task is reading
nodemask, and the write-side task clears newly disallowed nodes after
read-side task ends the current memory allocation.
[akpm@linux-foundation.org: fix spello]
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Paul Menage <menage@google.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nick Piggin reported that the allocator may see an empty nodemask when
changing cpuset's mems[1]. It happens only on the kernel that do not do
atomic nodemask_t stores. (MAX_NUMNODES > BITS_PER_LONG)
But I found that there is also a problem on the kernel that can do atomic
nodemask_t stores. The problem is that the allocator can't find a node to
alloc page when changing cpuset's mems though there is a lot of free
memory. The reason is like this:
(mpol: mempolicy)
task1 task1's mpol task2
alloc page 1
alloc on node0? NO 1
1 change mems from 1 to 0
1 rebind task1's mpol
0-1 set new bits
0 clear disallowed bits
alloc on node1? NO 0
...
can't alloc page
goto oom
I can use the attached program reproduce it by the following step:
# mkdir /dev/cpuset
# mount -t cpuset cpuset /dev/cpuset
# mkdir /dev/cpuset/1
# echo `cat /dev/cpuset/cpus` > /dev/cpuset/1/cpus
# echo `cat /dev/cpuset/mems` > /dev/cpuset/1/mems
# echo $$ > /dev/cpuset/1/tasks
# numactl --membind=`cat /dev/cpuset/mems` ./cpuset_mem_hog <nr_tasks> &
<nr_tasks> = max(nr_cpus - 1, 1)
# killall -s SIGUSR1 cpuset_mem_hog
# ./change_mems.sh
several hours later, oom will happen though there is a lot of free memory.
This patchset fixes this problem by expanding the nodes range first(set
newly allowed bits) and shrink it lazily(clear newly disallowed bits). So
we use a variable to tell the write-side task that read-side task is
reading nodemask, and the write-side task clears newly disallowed nodes
after read-side task ends the current memory allocation.
This patch:
In order to fix no node to alloc memory, when we want to update mempolicy
and mems_allowed, we expand the set of nodes first (set all the newly
nodes) and shrink the set of nodes lazily(clean disallowed nodes), But the
mempolicy's rebind functions may breaks the expanding.
So we restructure the mempolicy's rebind functions and split the rebind
work to two steps, just like the update of cpuset's mems: The 1st step:
expand the set of the mempolicy's nodes. The 2nd step: shrink the set of
the mempolicy's nodes. It is used when there is no real lock to protect
the mempolicy in the read-side. Otherwise we can do rebind work at once.
In order to implement it, we define
enum mpol_rebind_step {
MPOL_REBIND_ONCE,
MPOL_REBIND_STEP1,
MPOL_REBIND_STEP2,
MPOL_REBIND_NSTEP,
};
If the mempolicy needn't be updated by two steps, we can pass
MPOL_REBIND_ONCE to the rebind functions. Or we can pass
MPOL_REBIND_STEP1 to do the first step of the rebind work and pass
MPOL_REBIND_STEP2 to do the second step work.
Besides that, it maybe long time between these two step and we have to
release the lock that protects mempolicy and mems_allowed. If we hold the
lock once again, we must check whether the current mempolicy is under the
rebinding (the first step has been done) or not, because the task may
alloc a new mempolicy when we don't hold the lock. So we defined the
following flag to identify it:
#define MPOL_F_REBINDING (1 << 2)
The new functions will be used in the next patch.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Paul Menage <menage@google.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
putback_lru_page() never can fail. So it doesn't matter count of "the
number of pages put back".
In addition, users of this functions don't use return value.
Let's remove unnecessary code.
Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Shaohua Li reported parallel file copy on tmpfs can lead to OOM killer.
This is regression of caused by commit 9ff473b9a7 ("vmscan: evict
streaming IO first"). Wow, It is 2 years old patch!
Currently, tmpfs file cache is inserted active list at first. This means
that the insertion doesn't only increase numbers of pages in anon LRU, but
it also reduces anon scanning ratio. Therefore, vmscan will get totally
confused. It scans almost only file LRU even though the system has plenty
unused tmpfs pages.
Historically, lru_cache_add_active_anon() was used for two reasons.
1) Intend to priotize shmem page rather than regular file cache.
2) Intend to avoid reclaim priority inversion of used once pages.
But we've lost both motivation because (1) Now we have separate anon and
file LRU list. then, to insert active list doesn't help such priotize.
(2) In past, one pte access bit will cause page activation. then to
insert inactive list with pte access bit mean higher priority than to
insert active list. Its priority inversion may lead to uninteded lru
chun. but it was already solved by commit 645747462 (vmscan: detect
mapped file pages used only once). (Thanks Hannes, you are great!)
Thus, now we can use lru_cache_add_anon() instead.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reported-by: Shaohua Li <shaohua.li@intel.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A lot of condition comparision statements are used in original driver. These
statements are used to check the boundary of voltage numbers since voltage
number isn't linear.
Now use array of voltage numbers instead. Clean code with simpler way.
Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
