From 83224b08372be48d5fcefedc4886457da29130c8 Mon Sep 17 00:00:00 2001 From: Matt Helsley Date: Sat, 18 Oct 2008 20:27:18 -0700 Subject: container freezer: add TIF_FREEZE flag to all architectures 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 Signed-off-by: Matt Helsley Acked-by: Pavel Machek Acked-by: Serge E. Hallyn Acked-by: Rafael J. Wysocki Acked-by: Nigel Cunningham Tested-by: Matt Helsley Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/alpha/include/asm/thread_info.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/alpha') diff --git a/arch/alpha/include/asm/thread_info.h b/arch/alpha/include/asm/thread_info.h index 15fda4344424..d069526bd767 100644 --- a/arch/alpha/include/asm/thread_info.h +++ b/arch/alpha/include/asm/thread_info.h @@ -74,12 +74,14 @@ register struct thread_info *__current_thread_info __asm__("$8"); #define TIF_UAC_SIGBUS 7 #define TIF_MEMDIE 8 #define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal */ +#define TIF_FREEZE 16 /* is freezing for suspend */ #define _TIF_SYSCALL_TRACE (1<