The unit of the cputime accouting values that are stored per process is
currently a microsecond. The CPU timer has a maximum granularity of
2**-12 microseconds. There is no benefit in storing the per process values
in the lesser precision and there is the disadvantage that the backend
has to do the rounding to microseconds. The better solution is to use
the maximum granularity of the CPU timer as cputime unit.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch series introduces a cgroup subsystem that utilizes the swsusp
freezer to freeze a group of tasks. It's immediately useful for batch job
management scripts. It should also be useful in the future for
implementing container checkpoint/restart.
The freezer subsystem in the container filesystem defines a cgroup file
named freezer.state. Reading freezer.state will return the current state
of the cgroup. Writing "FROZEN" to the state file will freeze all tasks
in the cgroup. Subsequently writing "RUNNING" will unfreeze the tasks in
the cgroup.
* 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 patch:
The first step in making the refrigerator() available to all
architectures, even for those without power management.
The purpose of such a change is to be able to use the refrigerator() in a
new control group subsystem which will implement a control group freezer.
[akpm@linux-foundation.org: fix sparc]
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Acked-by: Pavel Machek <pavel@suse.cz>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Nigel Cunningham <nigel@tuxonice.net>
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>
* System call parameter and result access functions
* Add tracehook calls
* Split syscall_trace into two functions do_syscall_trace_enter and
do_syscall_trace_exit
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>