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>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/blackfin-2.6:
Blackfin arch: make sure cycles is marked as volatile so gcc doesnt reorder on us
Blackfin arch: disable CONFIG_HW_RANDOM and CONFIG_DAB in defconfig files
Blackfin arch: update cache flush prototypes with argument names to make them less mysterious
Blackfin arch: move bfin_addr_dcachable() and friends into the cacheflush header where it belongs
Blackfin arch: use the new bfin_addr_dcachable() function
Blackfin arch: fix bug - build kernel failed at head.S when reprogram clock on all platforms
Blackfin arch: unify/cleanup cache code
Blackfin arch: update AD7879 platform resources in board file
Blackfin arch: Zero out bss region in L1/L2 memory.
Blackfin arch: add read/write IO accessor functions to Blackfin
Blackfin arch: fix bug - some serial header files set RTS to an input when they should all be outputs
- to be correct wrt to end ranges
- to be optimal with a one-instruction hardware loop
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
The SET_PERSONALITY macro is always called with a second argument of 0.
Remove the ibcs argument and the various tests to set the PER_SVR4
personality.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
As policy->governor is already set to CPUFREQ_DEFAULT_GOVERNOR in the
(always built-in) cpufreq core, we do not need to set it in the drivers.
This fixes the sparc64 allmodconfig build failure.
Also, remove a totally useles setting of ->policy in cpufreq-pxa3xx.c.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/blackfin-2.6: (60 commits)
Blackfin arch: make sure we include the fix for SPORT hysteresis when reprogramming clocks
Blackfin arch: Fix bogus str_ident check in gpio code
Blackfin arch: AD7879 Touchscreen driver
Blackfin arch: introducing bfin_addr_dcachable
Blackfin arch: fix a typo in comments
Blackfin arch: Remove useless head file
Blackfin arch: make sure L2 start and length are always defined (fixes building on BF542)
Blackfin arch: use the Blackfin on-chip ROM to do software reset when possible
Blackfin arch: update anomaly headers to match the latest sheet
Blackfin arch: bfin_reset() is an internal reboot function ... everyone should go through machine_restart()
Blackfin arch: print out error/warning if you are running on the incorrect CPU type
Blackfin arch: remove non-bf54x ifdef logic since this file is only compiled on bf54x parts
Blackfin arch: update board defconfigs
Blackfin arch: Add optional verbose debug
Blackfin arch: emulate a TTY over the EMUDAT/JTAG interface
Blackfin arch: have is_user_addr_valid() check for overflows (like when address is -1)
Blackfin arch: ptrace - fix off-by-one check on end of memory regions
Blackfin arch: Enable framebuffer support for the BF526-EZkit TFT LCD display
Blackfin arch: flash memory map and dm9000 resources updating
Blackfin arch: early prink code still use uart core console functions to parse and set configure option string
...
* git://git.infradead.org/users/dwmw2/random-2.6:
Fix autoloading of MacBook Pro backlight driver.
Automatic MODULE_ALIAS() for DMI match tables.
Remove asm/a.out.h files for all architectures without a.out support.
Introduce HAVE_AOUT symbol to remove hard-coded arch list for BINFMT_AOUT
Remove redundant CONFIG_ARCH_SUPPORTS_AOUT
S390: Update comments about why we don't use <asm-generic/statfs.h>
SPARC: Use <asm-generic/statfs.h>
PowerPC: Use <asm-generic/statfs.h>
PARISC: Use <asm-generic/statfs.h>
x86_64: Use <asm-generic/statfs.h>
IA64: Use <asm-generic/statfs.h>
ARM: Use <asm-generic/statfs.h>
Make <asm-generic/statfs.h> suitable for 64-bit platforms.
Define and use PCI_DEVICE_ID_MARVELL_88ALP01_CCIC for CAFÉ camera driver
[MTD] [NAND] Define and use PCI_DEVICE_ID_MARVELL_88ALP01_NAND for CAFÉ
Use PCI_DEVICE_ID_88ALP01 for CAFÉ chip, rather than PCI_DEVICE_ID_CAFE.
EFS: Don't set f_fsid in statfs().
We now use the sir_dev/irtty_sir/uart/bfin_serial drivers framework
to monitor the TX status.
Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
move common variables out of serial headers and into the serial driver and
rename "nr_ports" to "nr_active_ports" so as to easily differentiate
between BFIN_UART_NR_PORTS (the # of available) and nr_ports (the # of enabled)
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As pointed out by Appalayagari Sreedhar, make sure we include the fix
for SPORT hysteresis when reprogramming clocks.
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
This patch introduces bfin_addr_dcachable() predicate, that simply tests is
address in cachable region or not.
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Add optional verbose debug - which when turned off, quiets down
userspace errors. Saves ~8k of code/data for production systems
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Move all the silicon rev handling to one place (Kconfig) and
make sure we warn if you are running on silicon that has not been tested on
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
avoid using actual config name in comment as a text search
is done to see what files need to be rebuilt
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
The kernel does not properly clear the EBIU Error Master (EBIU_ERRMST) Register
on BF548, which causes the kernel to panic.
We need to make sure that we clear the EBIU_ERRMST (necessary on BF54x)
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
a global _sys_trace will cause the assembler to fail, it should be fixed in toolchain side firstly.
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Matt Helsley