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/s390/include/asm/thread_info.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/s390/include/asm') diff --git a/arch/s390/include/asm/thread_info.h b/arch/s390/include/asm/thread_info.h index ea40a9d690fc..de3fad60c682 100644 --- a/arch/s390/include/asm/thread_info.h +++ b/arch/s390/include/asm/thread_info.h @@ -99,6 +99,7 @@ static inline struct thread_info *current_thread_info(void) #define TIF_31BIT 18 /* 32bit process */ #define TIF_MEMDIE 19 #define TIF_RESTORE_SIGMASK 20 /* restore signal mask in do_signal() */ +#define TIF_FREEZE 21 /* thread is freezing for suspend */ #define _TIF_SYSCALL_TRACE (1<