This patch implements a new freezer subsystem in the control groups
framework. It provides a way to stop and resume execution of all tasks in
a cgroup by writing in the cgroup filesystem.
The freezer subsystem in the container filesystem defines a file named
freezer.state. Writing "FROZEN" to the state file will freeze all tasks
in the cgroup. Subsequently writing "RUNNING" will unfreeze the tasks in
the cgroup. Reading will return the current state.
* Examples of usage :
# mkdir /containers/freezer
# mount -t cgroup -ofreezer freezer /containers
# mkdir /containers/0
# echo $some_pid > /containers/0/tasks
to get status of the freezer subsystem :
# cat /containers/0/freezer.state
RUNNING
to freeze all tasks in the container :
# echo FROZEN > /containers/0/freezer.state
# cat /containers/0/freezer.state
FREEZING
# cat /containers/0/freezer.state
FROZEN
to unfreeze all tasks in the container :
# echo RUNNING > /containers/0/freezer.state
# cat /containers/0/freezer.state
RUNNING
This is the basic mechanism which should do the right thing for user space
task in a simple scenario.
It's important to note that freezing can be incomplete. In that case we
return EBUSY. This means that some tasks in the cgroup are busy doing
something that prevents us from completely freezing the cgroup at this
time. After EBUSY, the cgroup will remain partially frozen -- reflected
by freezer.state reporting "FREEZING" when read. The state will remain
"FREEZING" until one of these things happens:
1) Userspace cancels the freezing operation by writing "RUNNING" to
the freezer.state file
2) Userspace retries the freezing operation by writing "FROZEN" to
the freezer.state file (writing "FREEZING" is not legal
and returns EIO)
3) The tasks that blocked the cgroup from entering the "FROZEN"
state disappear from the cgroup's set of tasks.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: export thaw_process]
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Tested-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds functionality to the gpio-lib subsystem to make it
possible to enable the gpio-lib code even if the architecture code didn't
request to get it built in.
The archtitecture code does still need to implement the gpiolib accessor
functions in its asm/gpio.h file. This patch adds the implementations for
x86 and PPC.
With these changes it is possible to run generic GPIO expansion cards on
every architecture that implements the trivial wrapper functions. Support
for more architectures can easily be added.
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: David Brownell <david-b@pacbell.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Samuel Ortiz <sameo@openedhand.com>
Cc: Kumar Gala <galak@gate.crashing.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Flag platforms as HAVE_CLK (or not) in Kconfig, based on whether they
support <linux/clk.h> calls, so that otherwise portable drivers which need
those calls can list that dependency.
Something like this is a prerequisite for merging the musb_hdrc driver,
currently used on platforms including Davinci, OMAP2430, OMAP3xx ... and
the discrete TUSB6010 chip, which doesn't have a natural platform
dependency. (Used with OMAP 2420 in current Nokia N8x0 tablets.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Implement Standby support. In this mode, we'll suspend all drivers,
put the SDRAM in self-refresh mode and switch off the HSB bus
("frozen" mode.)
Implement Suspend-to-mem support. In this mode, we suspend all
drivers, put the SDRAM into self-refresh mode and switch off all
internal clocks except the 32 kHz oscillator ("stop" mode.)
The lowest-level suspend code runs from a small portion of SRAM
allocated at startup time. This gets rid of a small potential race
with the SDRAM where we might try to enter self-refresh mode in the
middle of an icache burst. We also relocate all interrupt and
exception handlers to SRAM during the small window when we enter and
exit the low-power modes.
We don't need to do any special tricks to start and stop the PLL. The
main clock is automatically gated by hardware until the PLL is stable.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Use a quicklist to allocate process PGDs. This is expected to be
slightly faster since we need to copy entries from swapper_pg_dir,
which can stay around for pages on the PGD quick list.
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
This combines three patches from David Brownell:
* avr32: tclib support
* avr32: simplify clocksources
* avr32: Turn count/compare into a oneshot clockevent device
Register both TC blocks (instead of just the first one) so that
the AT32/AT91 tclib code will pick them up (instead of just the
avr32-only PIT-style clocksource).
Rename the first one and its resources appropriately.
More cleanups to the cycle counter clocksource code
- Disable all the weak symbol magic; remove the AVR32-only TCB-based
clocksource code (source and header).
- Mark the __init code properly.
- Don't forget to report IRQF_TIMER.
- Make the system work properly with this clocksource, by preventing
use of the CPU "idle" sleep state in the idle loop when it's used.
Package the avr32 count/compare timekeeping support as a oneshot
clockevent device, so it supports NO_HZ and high res timers.
This means it also supports plugging in other clockevent devices
and clocksources.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
There's a libata based PATA driver for avr32, but no support for
drivers/ide/ on avr32.
This patch fixes the following compile error:
<-- snip -->
...
CC [M] drivers/ide/ide-cd.o
In file included from /home/bunk/linux/kernel-2.6/git/linux-2.6/drivers/ide/ide-cd.c:37:
/home/bunk/linux/kernel-2.6/git/linux-2.6/include/linux/ide.h:209:21: error: asm/ide.h: No such file or directory
make[3]: *** [drivers/ide/ide-cd.o] Error 1
<-- snip -->
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
To allow flexible configuration of IDE introduce HAVE_IDE.
All archs except arm, um and s390 unconditionally select it.
For arm the actual configuration determine if IDE is supported.
This is a step towards introducing drivers/Kconfig for arm.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Russell King - ARM Linux <linux@arm.linux.org.uk>
Acked-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Teach AVR32 to use the "GPIO Library" when exposing its GPIOs, so that signals
on external chips (like GPIO expanders) can easily be used.
This mostly reorganizes some existing logic, with two minor changes in
behavior:
- The PSR registers are used instead of the previous "gpio_mask" values,
matching AT91 behavior and removing some duplication between that role
and that of "pinmux_mask".
- NR_IRQs grew to acommodate a bank of external GPIOs. Eventually this
number should probably become a board-specific config option.
There's a debugfs dump of status for the built-in GPIOs, showing which pins
have deglitching, pullups, or open drain drive enabled, as well as the ID
string used when requesting each IRQ.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Eric Miao <eric.miao@marvell.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Philipp Zabel <philipp.zabel@gmail.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ben Gardner <bgardner@wabtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
AVR32 still includes Kconfig.instrumentation, so it won't build after
this...
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus:
On the per-architecture side, I do think it would be better to *not* have
internal architecture knowledge in a generic file, and as such a line like
depends on X86_32 || IA64 || PPC || S390 || SPARC64 || X86_64 || AVR32
really shouldn't exist in a file like kernel/Kconfig.instrumentation.
It would be much better to do
depends on ARCH_SUPPORTS_KPROBES
in that generic file, and then architectures that do support it would just
have a
bool ARCH_SUPPORTS_KPROBES
default y
in *their* architecture files. That would seem to be much more logical,
and is readable both for arch maintainers *and* for people who have no
clue - and don't care - about which architecture is supposed to support
which interface...
Changelog:
Actually, I know I gave this as the magic incantation, but now that I see
it, I realize that I should have told you to just use
config KPROBES_SUPPORT
def_bool y
instead, which is a bit denser.
We seem to use both kinds of syntax for these things, but this is really
what "def_bool" is there for...
- Use HAVE_KPROBES
- Use a select
- Yet another update :
Moving to HAVE_* now.
- Update ARM for kprobes support.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Linus:
On the per-architecture side, I do think it would be better to *not* have
internal architecture knowledge in a generic file, and as such a line like
depends on X86_32 || IA64 || PPC || S390 || SPARC64 || X86_64 || AVR32
really shouldn't exist in a file like kernel/Kconfig.instrumentation.
It would be much better to do
depends on ARCH_SUPPORTS_KPROBES
in that generic file, and then architectures that do support it would just
have a
bool ARCH_SUPPORTS_KPROBES
default y
in *their* architecture files. That would seem to be much more logical,
and is readable both for arch maintainers *and* for people who have no
clue - and don't care - about which architecture is supposed to support
which interface...
Changelog:
Actually, I know I gave this as the magic incantation, but now that I see
it, I realize that I should have told you to just use
config ARCH_SUPPORTS_KPROBES
def_bool y
instead, which is a bit denser.
We seem to use both kinds of syntax for these things, but this is really
what "def_bool" is there for...
Changelog :
- Moving to HAVE_*.
- Add AVR32 oprofile.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Change the NMI handler to use the die notifier chain to signal anyone
who cares. Add a simple "nmi debugger" which hooks into this chain and
that may dump registers, task state, etc. when it happens.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Remove the CPU selection menu and instead let it be selected by the
board or daughterboard option. Add daughterboard selection for
ATSTK1000 (this was previously determined based on CPU type.)
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
ATSTK1003 and ATSTK1004 are CPU daughterboards for ATSTK1000 featuring
the AT32AP7001 and AT32AP7002 CPUs, respectively.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
These are derivatives of the AT32AP7000 chip, which means that most of
the code stays the same. Rename a few files, functions, definitions
and config symbols to reflect that they apply to all AP700x chips, and
exclude some platform devices from chips where they aren't present.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
This adds the necessary architecture code to run oprofile on AVR32
using the performance counters documented by the AVR32 Architecture
Manual.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: Philippe Elie <phil.el@wanadoo.fr>
avr32 already sees the option from init/Kconfig.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Most of these fixes were already submitted for old kernel versions, and were
approved, but for some reason they never made it into the releases.
Because this is a consolidation of a couple old missed patches, it touches both
Kconfigs and documentation texts.
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
This adds some STK1002-specific config options covering the jumper settings,
so the kernel can automatically be configured to include the relevant devices.
One of them replaces the previous internal SW2_DEFAULT setting; SPI config
is affected by two of the jumpers; and a fourth one switches between LCD and
the second Ethernet connector. (There's more that to be done.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
This patch enables CPU frequency scaling for AT32AP devices. This will
enable the CPU to scale between the speed of the high speed bus and
the master clock and thus save some power.
The patch also adds a parent to cpu_clk and a cpu_clk_set_rate to
enable changing the CPU clock divider in a sane way.
The driver does not check if the given rate is 0, thus resulting in a
div by 0. I think this check should be go into the clk_set_rate
framework, and not here.
Tested on AT32AP7000/ATSTK1000.
Hardware documentation can be found in the AT32AP7000 datasheet.
Signed-off-by: Hans-Christian Egtvedt <hcegtvedt@atmel.com>
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Remove the clearly useless config option GENERIC_BUST_SPINLOCK, which
is not used anywhere in the tree.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
* Use generic BUG() handling
* Remove some useless debug statements
* Use a common function _exception() to send signals or oops when
an exception can't be handled. This makes sure init doesn't
enter an infinite exception loop as well. Borrowed from powerpc.
* Add some basic exception tracing support to the page fault code.
* Rework dump_stack(), show_regs() and friends and move everything
into process.c
* Print information about configuration options and chip type when
oopsing
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Include at32ap-specific Kconfig file from top-level Kconfig file. The
at32ap Kconfig is currently empty, but it will grow some machine-
specific options soon.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Most drivers using GPIOs already know they are running on a system that
supports the generic GPIO calls, because of other platform dependencies.
But the generic GPIO-based LED and input button drivers can't know that.
So this patch adds a Kconfig hook, GENERIC_GPIO, to mark the platforms
where <asm/gpio.h> will do the right thing. Currently that's a bunch of
ARMs, and AVR32; more are on the way.
It also fixes a dependency bug for the gpio button input driver; it was
wrong to start with, now it covers all platforms with GENERIC_GPIO.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
Cc: <raph@8d.com>
Cc: <msvoboda@ra.rockwell.com>
Cc: pHilipp Zabel <philipp.zabel@gmail.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
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>
This facility provides three entry points:
ilog2() Log base 2 of unsigned long
ilog2_u32() Log base 2 of u32
ilog2_u64() Log base 2 of u64
These facilities can either be used inside functions on dynamic data:
int do_something(long q)
{
...;
y = ilog2(x)
...;
}
Or can be used to statically initialise global variables with constant values:
unsigned n = ilog2(27);
When performing static initialisation, the compiler will report "error:
initializer element is not constant" if asked to take a log of zero or of
something not reducible to a constant. They treat negative numbers as
unsigned.
When not dealing with a constant, they fall back to using fls() which permits
them to use arch-specific log calculation instructions - such as BSR on
x86/x86_64 or SCAN on FRV - if available.
[akpm@osdl.org: MMC fix]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Wojtek Kaniewski <wojtekka@toxygen.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds support for the Atmel AVR32 architecture as well as the AT32AP7000
CPU and the AT32STK1000 development board.
AVR32 is a new high-performance 32-bit RISC microprocessor core, designed for
cost-sensitive embedded applications, with particular emphasis on low power
consumption and high code density. The AVR32 architecture is not binary
compatible with earlier 8-bit AVR architectures.
The AVR32 architecture, including the instruction set, is described by the
AVR32 Architecture Manual, available from
http://www.atmel.com/dyn/resources/prod_documents/doc32000.pdf
The Atmel AT32AP7000 is the first CPU implementing the AVR32 architecture. It
features a 7-stage pipeline, 16KB instruction and data caches and a full
Memory Management Unit. It also comes with a large set of integrated
peripherals, many of which are shared with the AT91 ARM-based controllers from
Atmel.
Full data sheet is available from
http://www.atmel.com/dyn/resources/prod_documents/doc32003.pdf
while the CPU core implementation including caches and MMU is documented by
the AVR32 AP Technical Reference, available from
http://www.atmel.com/dyn/resources/prod_documents/doc32001.pdf
Information about the AT32STK1000 development board can be found at
http://www.atmel.com/dyn/products/tools_card.asp?tool_id=3918
including a BSP CD image with an earlier version of this patch, development
tools (binaries and source/patches) and a root filesystem image suitable for
booting from SD card.
Alternatively, there's a preliminary "getting started" guide available at
http://avr32linux.org/twiki/bin/view/Main/GettingStarted which provides links
to the sources and patches you will need in order to set up a cross-compiling
environment for avr32-linux.
This patch, as well as the other patches included with the BSP and the
toolchain patches, is actively supported by Atmel Corporation.
[dmccr@us.ibm.com: Fix more pxx_page macro locations]
[bunk@stusta.de: fix `make defconfig']
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Dave McCracken <dmccr@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>