it's x86-only and we have no business playing with it in asm/mmu.h; make
the latter have
struct uml_arch_mm_context arch;
instead of
struct uml_ldt ldt;
and let arch/<subarch>/um/asm/mm_context.h decide what'll be in there.
While we are at it, kill host_ldt.h - it's not needed in part of places
that include it (we want asm/ldt.h in those) and it can be trivially
expanded into the single remaining one.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
analog of [PATCH] i386: let usermode execute the "enter" instruction from
circa 2006.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
it's i386-specific; moreover, analogs on other targets have
incompatible interface - PTRACE_GET_THREAD_AREA does exist
elsewhere, but struct user_desc does *not*
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
most of the functions in there are not used in anything that ends up
including that header...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
now we don't mix host and guest signal frame layouts anymore; moreover,
we don't need host's struct sigcontext at all.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
For one thing, we always block the same signals (IRQ ones - IO, WINCH, VTALRM),
so there's no need to pass sa_mask elements in arguments. For another, the
flags depend only on whether it's an IRQ signal or not (we add SA_RESTART
for them).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
We used to generate those, but we hadn't done that for a long
time. No need to bother blocking them for signal handlers.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
only sysdep/sigcontext.h uses it and very few definitions are
actually used. The rest refers to symbols that don't even
exist anymore anyway.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
the only users are arch getreg()/putreg() and it's easier to handle
it there instead of playing with macros from hell
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
Move those to sys-.../asm/checksum.h, kill include/asm/checksum.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
It's a plain include of user_constants.h and all (2) users are
including user_constants.h directly prior to that.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
It's not x86, where __get_user() is a single dereference; here it's
a single ptrace(2) call in host, which obviously costs a lot more.
IOW, it's cheaper to do copy_{to,from}_user() once than bother with
fields one by one...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
Replace remaining direct i_nlink updates with a new set_nlink()
updater function.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Replace direct i_nlink updates with the respective updater function
(inc_nlink, drop_nlink, clear_nlink, inode_dec_link_count).
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* 'next/soc' of git://git.linaro.org/people/arnd/arm-soc: (21 commits)
MAINTAINERS: add ARM/FREESCALE IMX6 entry
arm/imx: merge i.MX3 and i.MX6
arm/imx6q: add suspend/resume support
arm/imx6q: add device tree machine support
arm/imx6q: add smp and cpu hotplug support
arm/imx6q: add core drivers clock, gpc, mmdc and src
arm/imx: add gic_handle_irq function
arm/imx6q: add core definitions and low-level debug uart
arm/imx6q: add device tree source
ARM: highbank: add suspend support
ARM: highbank: Add cpu hotplug support
ARM: highbank: add SMP support
MAINTAINERS: add Calxeda Highbank ARM platform
ARM: add Highbank core platform support
ARM: highbank: add devicetree source
ARM: l2x0: add empty l2x0_of_init
picoxcell: add a definition of VMALLOC_END
picoxcell: remove custom ioremap implementation
picoxcell: add the DTS for the PC7302 board
picoxcell: add the DTS for pc3x2 and pc3x3 devices
...
Fix up trivial conflicts in arch/arm/Kconfig, and some more header file
conflicts in arch/arm/mach-omap2/board-generic.c (as per an ealier merge
by Arnd).
* 'next/dt' of git://git.linaro.org/people/arnd/arm-soc:
ARM: gic: use module.h instead of export.h
ARM: gic: fix irq_alloc_descs handling for sparse irq
ARM: gic: add OF based initialization
ARM: gic: add irq_domain support
irq: support domains with non-zero hwirq base
of/irq: introduce of_irq_init
ARM: at91: add at91sam9g20 and Calao USB A9G20 DT support
ARM: at91: dt: at91sam9g45 family and board device tree files
arm/mx5: add device tree support for imx51 babbage
arm/mx5: add device tree support for imx53 boards
ARM: msm: Add devicetree support for msm8660-surf
msm_serial: Add devicetree support
msm_serial: Use relative resources for iomem
Fix up conflicts in arch/arm/mach-at91/{at91sam9260.c,at91sam9g45.c}
* 'next/cleanup2' of git://git.linaro.org/people/arnd/arm-soc: (31 commits)
ARM: OMAP: Warn if omap_ioremap is called before SoC detection
ARM: OMAP: Move set_globals initialization to happen in init_early
ARM: OMAP: Map SRAM later on with ioremap_exec()
ARM: OMAP: Remove calls to SRAM allocations for framebuffer
ARM: OMAP: Avoid cpu_is_omapxxxx usage until map_io is done
ARM: OMAP1: Use generic map_io, init_early and init_irq
arm/dts: OMAP3+: Add mpu, dsp and iva nodes
arm/dts: OMAP4: Add a main ocp entry bound to l3-noc driver
ARM: OMAP2+: l3-noc: Add support for device-tree
ARM: OMAP2+: board-generic: Add i2c static init
ARM: OMAP2+: board-generic: Add DT support to generic board
arm/dts: Add support for OMAP3 Beagle board
arm/dts: Add initial device tree support for OMAP3 SoC
arm/dts: Add support for OMAP4 SDP board
arm/dts: Add support for OMAP4 PandaBoard
arm/dts: Add initial device tree support for OMAP4 SoC
ARM: OMAP: omap_device: Add a method to build an omap_device from a DT node
ARM: OMAP: omap_device: Add omap_device_[alloc|delete] for DT integration
of: Add helpers to get one string in multiple strings property
ARM: OMAP2+: devices: Remove all omap_device_pm_latency structures
...
Fix up trivial header file conflicts in arch/arm/mach-omap2/board-generic.c
* 'next/cross-platform' of git://git.linaro.org/people/arnd/arm-soc:
arm/imx: use Kconfig choice for low-level debug UART selection
ARM: realview: use Kconfig choice for debug UART selection
ARM: plat-samsung: use Kconfig choice for debug UART selection
ARM: versatile: convert logical CPU numbers to physical numbers
ARM: ux500: convert logical CPU numbers to physical numbers
ARM: shmobile: convert logical CPU numbers to physical numbers
ARM: msm: convert logical CPU numbers to physical numbers
ARM: exynos4: convert logical CPU numbers to physical numbers
Fix up trivial conflict (config DEBUG_S3C_UART move/split vs addition of
ARM_KPROBES_TEST option) in arch/arm/Kconfig.debug
* 'next/devel' of git://git.linaro.org/people/arnd/arm-soc: (50 commits)
ARM: tegra: update defconfig
arm/tegra: Harmony: Configure PMC for low-level interrupts
arm/tegra: device tree support for ventana board
arm/tegra: add support for ventana pinmuxing
arm/tegra: prepare Seaboard pinmux code for derived boards
arm/tegra: pinmux: ioremap registers
gpio/tegra: Convert to a platform device
arm/tegra: Convert pinmux driver to a platform device
arm/dt: Tegra: Add pinmux node to tegra20.dtsi
arm/tegra: Prep boards for gpio/pinmux conversion to pdevs
ARM: mx5: fix clock usage for suspend
ARM i.MX entry-macro.S: remove now unused code
ARM i.MX boards: use CONFIG_MULTI_IRQ_HANDLER
ARM i.MX tzic: add handle_irq function
ARM i.MX avic: add handle_irq function
ARM: mx25: Add the missing IIM base definition
ARM i.MX avic: convert to use generic irq chip
mx31moboard: Add poweroff support
ARM: mach-qong: Add watchdog support
ARM: davinci: AM18x: Add wl1271/wlan support
...
Fix up conflicts in:
arch/arm/mach-at91/at91sam9g45.c
arch/arm/mach-mx5/devices-imx53.h
arch/arm/plat-mxc/include/mach/memory.h
* 'next/board' of git://git.linaro.org/people/arnd/arm-soc: (34 commits)
ep93xx: add support Vision EP9307 SoM
ARM: mxs: Add initial support for DENX MX28
ARM: EXYNOS4: Add support SMDK4412 Board
ARM: EXYNOS4: Add MCT support for EXYNOS4412
ARM: EXYNOS4: Add functions for gic interrupt handling
ARM: EXYNOS4: Add support clock for EXYNOS4412
ARM: EXYNOS4: Add support new EXYNOS4412 SoC
ARM: EXYNOS4: Add support MCT PPI for EXYNOS4212
ARM: EXYNOS4: Add support PPI in external GIC
ARM: EXYNOS4: convert boot_params to atag_offset
ixp4xx: support omicron ixp425 based boards
ARM: EXYNOS4: Add support SMDK4212 Board
ARM: EXYNOS4: Add support PM for EXYNOS4212
ARM: EXYNOS4: Add support clock for EXYNOS4212
ARM: EXYNOS4: Add support new EXYNOS4212 SoC
at91: USB-A9G20 C01 & C11 board support
at91: merge board USB-A9260 and USB-A9263 together
at91: add support for RSIs EWS board
ARM: SAMSUNG: Fix mask value for S5P64X0 CPU IDs
ARM: SAMSUNG: Fix mask for S3C64xx CPU IDs
...
* 'next/deletion' of git://git.linaro.org/people/arnd/arm-soc:
ARM: mach-nuc93x: delete
Fix up trivial delete/edit conflicts in
arch/arm/mach-nuc93x/{Makefile.boot,mach-nuc932evb.c,time.c}
* 'next/pm' of git://git.linaro.org/people/arnd/arm-soc: (66 commits)
ARM: CSR: PM: use outer_resume to resume L2 cache
ARM: CSR: call l2x0_of_init to init L2 cache of SiRFprimaII
ARM: OMAP: voltage: voltage layer present, even when CONFIG_PM=n
ARM: CSR: PM: add sleep entry for SiRFprimaII
ARM: CSR: PM: save/restore irq status in suspend cycle
ARM: CSR: PM: save/restore timer status in suspend cycle
OMAP4: PM: TWL6030: add cmd register
OMAP4: PM: TWL6030: fix ON/RET/OFF voltages
OMAP4: PM: TWL6030: address 0V conversions
OMAP4: PM: TWL6030: fix uv to voltage for >0x39
OMAP4: PM: TWL6030: fix voltage conversion formula
omap: voltage: add a stub header file for external/regulator use
OMAP2+: VC: more registers are per-channel starting with OMAP5
OMAP3+: voltage: update nominal voltage in voltdm_scale() not VC post-scale
OMAP3+: voltage: rename omap_voltage_get_nom_volt -> voltdm_get_voltage
OMAP3+: voltdm: final removal of omap_vdd_info
OMAP3+: voltage: move/rename curr_volt from vdd_info into struct voltagedomain
OMAP3+: voltage: rename scale and reset functions using voltdm_ prefix
OMAP3+: VP: combine setting init voltage into common function
OMAP3+: VP: remove unused omap_vp_get_curr_volt()
...
Fix up trivial conflict in arch/arm/mach-prima2/l2x0.c (code removal vs
edit)
* 'next/driver' of git://git.linaro.org/people/arnd/arm-soc:
hw_random: add driver for atmel true hardware random number generator
ARM: at91: at91sam9g45: add trng clock and platform device
MX53 Enable the AHCI SATA on MX53 SMD board
MX53 Enable the AHCI SATA on MX53 LOCO board
MX53 Enable the AHCI SATA on MX53 ARD board
AHCI Add the AHCI SATA feature on the MX53 platforms
Fix pata imx resource
ARM: imx: Define functions for registering PATA
ARM: imx: Add PATA clock support
ARM: imx: Add PATA resources for other i.MX processors
imx: efika: Enable pata.
imx51: add pata clock
imx51: add pata device
Fix up trivial conflict (new selects next to each other from separate
branches for EFIKA_COMMON) in arch/arm/mach-mx5/Kconfig
* 'next/fixes' of git://git.linaro.org/people/arnd/arm-soc: (28 commits)
ARM: pxa/cm-x300: properly set bt_reset pin
ARM: mmp: rename SHEEVAD to GPLUGD
ARM: imx: Fix typo 'MACH_MX31_3DS_MXC_NAND_USE_BBT'
ARM: i.MX28: shift frac value in _CLK_SET_RATE
plat-mxc: iomux-v3.h: implicitly enable pull-up/down when that's desired
ARM: mx5: fix clock usage for suspend
ARM: pxa: use correct __iomem annotations
ARM: pxa: sharpsl pm needs SPI
ARM: pxa: centro and treo680 need palm27x
ARM: pxa: make pxafb_smart_*() empty when not enabled
ARM: pxa: select POWER_SUPPLY on raumfeld
ARM: pxa: pxa95x is incompatible with earlier pxa
ARM: pxa: CPU_FREQ_TABLE is needed for CPU_FREQ
ARM: pxa: pxa95x/saarb depends on pxa3xx code
ARM: pxa: allow selecting just one of TREO680/CENTRO
ARM: pxa: export symbols from pxa3xx-ulpi
ARM: pxa: make zylonite_pxa*_init declaration match code
ARM: pxa/z2: fix building error of pxa27x_cpu_suspend() no longer available
ARM: at91: add defconfig for at91sam9g45 family
ARM: at91: remove dependency for Atmel PWM driver selector in Kconfig
...
* 'for-linus/i2c-3.2' of git://git.fluff.org/bjdooks/linux: (47 commits)
i2c-s3c2410: Add device tree support
i2c-s3c2410: Keep a copy of platform data and use it
i2c-nomadik: cosmetic coding style corrections
i2c-au1550: dev_pm_ops conversion
i2c-au1550: increase timeout waiting for master done
i2c-au1550: remove unused ack_timeout
i2c-au1550: remove usage of volatile keyword
i2c-tegra: __iomem annotation fix
i2c-eg20t: Add initialize processing in case i2c-error occurs
i2c-eg20t: Fix flag setting issue
i2c-eg20t: add stop sequence in case wait-event timeout occurs
i2c-eg20t: Separate error processing
i2c-eg20t: Fix 10bit access issue
i2c-eg20t: Modify returned value s32 to long
i2c-eg20t: Fix bus-idle waiting issue
i2c-designware: Fix PCI core warning on suspend/resume
i2c-designware: Add runtime power management support
i2c-designware: Add support for Designware core behind PCI devices.
i2c-designware: Push all register reads/writes into the core code.
i2c-designware: Support multiple cores using same ISR
...
* git://github.com/herbertx/crypto: (48 commits)
crypto: user - Depend on NET instead of selecting it
crypto: user - Add dependency on NET
crypto: talitos - handle descriptor not found in error path
crypto: user - Initialise match in crypto_alg_match
crypto: testmgr - add twofish tests
crypto: testmgr - add blowfish test-vectors
crypto: Make hifn_795x build depend on !ARCH_DMA_ADDR_T_64BIT
crypto: twofish-x86_64-3way - fix ctr blocksize to 1
crypto: blowfish-x86_64 - fix ctr blocksize to 1
crypto: whirlpool - count rounds from 0
crypto: Add userspace report for compress type algorithms
crypto: Add userspace report for cipher type algorithms
crypto: Add userspace report for rng type algorithms
crypto: Add userspace report for pcompress type algorithms
crypto: Add userspace report for nivaead type algorithms
crypto: Add userspace report for aead type algorithms
crypto: Add userspace report for givcipher type algorithms
crypto: Add userspace report for ablkcipher type algorithms
crypto: Add userspace report for blkcipher type algorithms
crypto: Add userspace report for ahash type algorithms
...
The board changes in the imx/devel branch conflict with other changes in
the device imx/dt branch.
Conflicts:
arch/arm/mach-mx5/board-mx53_loco.c
arch/arm/mach-mx5/board-mx53_smd.c
arch/arm/plat-mxc/include/mach/common.h
arch/arm/plat-mxc/include/mach/memory.h
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This is the fifth version of the patchset (with one tiny whitespace fix)
to the Linux kernel to support the Qualcomm Hexagon architecture.
Between now and the next pull requests, Richard Kuo should have his key
signed, etc., and should be back on kernel.org. In the meantime, this
got merged as a emailed patch-series.
* Hexagon: (36 commits)
Add extra arch overrides to asm-generic/checksum.h
Hexagon: Add self to MAINTAINERS
Hexagon: Add basic stacktrace functionality for Hexagon architecture.
Hexagon: Add configuration and makefiles for the Hexagon architecture.
Hexagon: Comet platform support
Hexagon: kgdb support files
Hexagon: Add page-fault support.
Hexagon: Add page table header files & etc.
Hexagon: Add ioremap support
Hexagon: Provide DMA implementation
Hexagon: Implement basic TLB management routines for Hexagon.
Hexagon: Implement basic cache-flush support
Hexagon: Provide basic implementation and/or stubs for I/O routines.
Hexagon: Add user access functions
Hexagon: Add locking types and functions
Hexagon: Add SMP support
Hexagon: Provide basic debugging and system trap support.
Hexagon: Add ptrace support
Hexagon: Add time and timer functions
Hexagon: Add interrupts
...
Mostly all stubs, as the TLB is managed by the hypervisor.
Signed-off-by: Richard Kuo <rkuo@codeaurora.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Modules should be compiled as ordinary .o's; shared objects are not
supported.
Signed-off-by: Linas Vepstas <linas@codeaurora.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Richard Kuo <rkuo@codeaurora.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove edac_mce pieces and use the normal MCE decoder notifier chain by
retaining the same functionality with considerably less code.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
There are lots of conflicts between the omap and exynos cleanups
and the memory.h remove series.
Conflicts:
arch/arm/mach-exynos4/mach-smdkc210.c
arch/arm/mach-exynos4/mach-smdkv310.c
arch/arm/mach-imx/mach-cpuimx27.c
arch/arm/mach-omap1/board-ams-delta.c
arch/arm/mach-omap1/board-generic.c
arch/arm/mach-omap1/board-h2.c
arch/arm/mach-omap1/board-h3.c
arch/arm/mach-omap1/board-nokia770.c
arch/arm/mach-omap1/board-osk.c
arch/arm/mach-omap1/board-palmte.c
arch/arm/mach-omap1/board-palmtt.c
arch/arm/mach-omap1/board-palmz71.c
arch/arm/mach-omap1/board-sx1.c
arch/arm/mach-omap1/board-voiceblue.c
arch/arm/mach-omap1/io.c
arch/arm/mach-omap2/board-generic.c
arch/arm/mach-omap2/io.c
arch/arm/plat-omap/io.c
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Quoth Andrew:
- Most of MM. Still waiting for the poweroc guys to get off their
butts and review some threaded hugepages patches.
- alpha
- vfs bits
- drivers/misc
- a few core kerenl tweaks
- printk() features
- MAINTAINERS updates
- backlight merge
- leds merge
- various lib/ updates
- checkpatch updates
* akpm: (127 commits)
epoll: fix spurious lockdep warnings
checkpatch: add a --strict check for utf-8 in commit logs
kernel.h/checkpatch: mark strict_strto<foo> and simple_strto<foo> as obsolete
llist-return-whether-list-is-empty-before-adding-in-llist_add-fix
wireless: at76c50x: follow rename pack_hex_byte to hex_byte_pack
fat: follow rename pack_hex_byte() to hex_byte_pack()
security: follow rename pack_hex_byte() to hex_byte_pack()
kgdb: follow rename pack_hex_byte() to hex_byte_pack()
lib: rename pack_hex_byte() to hex_byte_pack()
lib/string.c: fix strim() semantics for strings that have only blanks
lib/idr.c: fix comment for ida_get_new_above()
lib/percpu_counter.c: enclose hotplug only variables in hotplug ifdef
lib/bitmap.c: quiet sparse noise about address space
lib/spinlock_debug.c: print owner on spinlock lockup
lib/kstrtox: common code between kstrto*() and simple_strto*() functions
drivers/leds/leds-lp5521.c: check if reset is successful
leds: turn the blink_timer off before starting to blink
leds: save the delay values after a successful call to blink_set()
drivers/leds/leds-gpio.c: use gpio_get_value_cansleep() when initializing
drivers/leds/leds-lm3530.c: add __devexit_p where needed
...
There is no functional change.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The regulator support in the l4f00242t03 is very non-idiomatic. Rather
than requesting the regulators based on the device name and the supply
names used by the device the driver requires boards to pass system
specific supply names around through platform data. The driver also
conditionally requests the regulators based on this platform data, adding
unneeded conditional code to the driver.
Fix this by removing the platform data and converting to the standard
idiom, also updating all in tree users of the driver. As no datasheet
appears to be available for the LCD I'm guessing the names for the
supplies based on the existing users and I've no ability to do anything
more than compile test.
The use of regulator_set_voltage() in the driver is also problematic,
since fixed voltages are required the expectation would be that the
voltages would be fixed in the constraints set by the machines rather than
manually configured by the driver, but is less problematic.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Michael Cree <mcree@orcon.net.nz>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Somehow wiring up the accept4 syscall on Alpha was missed long ago.
This commit rectifies that oversight.
Signed-off-by: Michael Cree <mcree@orcon.net.nz>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The basic idea behind cross memory attach is to allow MPI programs doing
intra-node communication to do a single copy of the message rather than a
double copy of the message via shared memory.
The following patch attempts to achieve this by allowing a destination
process, given an address and size from a source process, to copy memory
directly from the source process into its own address space via a system
call. There is also a symmetrical ability to copy from the current
process's address space into a destination process's address space.
- Use of /proc/pid/mem has been considered, but there are issues with
using it:
- Does not allow for specifying iovecs for both src and dest, assuming
preadv or pwritev was implemented either the area read from or
written to would need to be contiguous.
- Currently mem_read allows only processes who are currently
ptrace'ing the target and are still able to ptrace the target to read
from the target. This check could possibly be moved to the open call,
but its not clear exactly what race this restriction is stopping
(reason appears to have been lost)
- Having to send the fd of /proc/self/mem via SCM_RIGHTS on unix
domain socket is a bit ugly from a userspace point of view,
especially when you may have hundreds if not (eventually) thousands
of processes that all need to do this with each other
- Doesn't allow for some future use of the interface we would like to
consider adding in the future (see below)
- Interestingly reading from /proc/pid/mem currently actually
involves two copies! (But this could be fixed pretty easily)
As mentioned previously use of vmsplice instead was considered, but has
problems. Since you need the reader and writer working co-operatively if
the pipe is not drained then you block. Which requires some wrapping to
do non blocking on the send side or polling on the receive. In all to all
communication it requires ordering otherwise you can deadlock. And in the
example of many MPI tasks writing to one MPI task vmsplice serialises the
copying.
There are some cases of MPI collectives where even a single copy interface
does not get us the performance gain we could. For example in an
MPI_Reduce rather than copy the data from the source we would like to
instead use it directly in a mathops (say the reduce is doing a sum) as
this would save us doing a copy. We don't need to keep a copy of the data
from the source. I haven't implemented this, but I think this interface
could in the future do all this through the use of the flags - eg could
specify the math operation and type and the kernel rather than just
copying the data would apply the specified operation between the source
and destination and store it in the destination.
Although we don't have a "second user" of the interface (though I've had
some nibbles from people who may be interested in using it for intra
process messaging which is not MPI). This interface is something which
hardware vendors are already doing for their custom drivers to implement
fast local communication. And so in addition to this being useful for
OpenMPI it would mean the driver maintainers don't have to fix things up
when the mm changes.
There was some discussion about how much faster a true zero copy would
go. Here's a link back to the email with some testing I did on that:
http://marc.info/?l=linux-mm&m=130105930902915&w=2
There is a basic man page for the proposed interface here:
http://ozlabs.org/~cyeoh/cma/process_vm_readv.txt
This has been implemented for x86 and powerpc, other architecture should
mainly (I think) just need to add syscall numbers for the process_vm_readv
and process_vm_writev. There are 32 bit compatibility versions for
64-bit kernels.
For arch maintainers there are some simple tests to be able to quickly
verify that the syscalls are working correctly here:
http://ozlabs.org/~cyeoh/cma/cma-test-20110718.tgz
Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: <linux-man@vger.kernel.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We need this in advance of the module.h cleanup, or we'll
get compile errors like this:
CC drivers/lguest/lguest_device.o
drivers/lguest/lguest_device.c: In function ‘lguest_devices_init’:
drivers/lguest/lguest_device.c:490: error: ‘THIS_MODULE’ undeclared (first use in this function)
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Include export.h to fix below warning:
CC arch/unicore32/mm/init.o
arch/unicore32/mm/init.c:227: warning: data definition has no type or storage class
arch/unicore32/mm/init.c:227: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL'
arch/unicore32/mm/init.c:227: warning: parameter names (without types) in function declaration
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
To fix:
arch/sh/drivers/dma/dma-sysfs.c:45:8: error: 'S_IRUGO' undeclared here (not in a function)
arch/sh/drivers/dma/dma-sysfs.c:75:8: error: 'S_IWUSR' undeclared here (not in a function)
make[4]: *** [arch/sh/drivers/dma/dma-sysfs.o] Error 1
drivers/sh/intc/core.c:449: error: 'S_IRUGO' undeclared here (not in a function)
make[5]: *** [drivers/sh/intc/core.o] Error 1
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
To avoid this:
arch/alpha/kernel/pci-sysfs.c:164: error: 'S_IRUSR' undeclared (first use in this function)
arch/alpha/kernel/pci-sysfs.c:164: error: 'S_IWUSR' undeclared (first use in this function)
make[2]: *** [arch/alpha/kernel/pci-sysfs.o] Error 1
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Its presence was implicit everywhere, but we are aiming to fix that,
so call out the users explicitly.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
These particular files were just assuming that module.h was
somehow in the include paths. Give them the more minimalist
header file explicitly.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Fix several compile errors on s390 caused by splitting module.h.
Some include additions [e.g. qdio_setup.c, zfcp_qdio.c] are in
anticipation of pending changes queued for s390 that increase
the modular use footprint.
[PG: added additional obvious changes since Heiko's original patch]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Or else we get lots of variations on this:
arch/mips/pci/pci.c:330: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL'
scattered throughout the build.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Al Viro
Miklos Szeredi
Linus Torvalds
Arnd Bergmann
Richard Kuo
Linas Vepstas
Borislav Petkov
Nobuhiro Iwamatsu
Ben Dooks
Andy Shevchenko
Mark Brown
Michael Cree
Christopher Yeoh
Paul Gortmaker
Axel Lin
Heiko Carstens