Container Freezer: Reuse Suspend Freezer

cover

   # mkdir /containers/freezer
   # mount -t cgroup -ofreezer,signal freezer  /containers/freezer
   # mkdir /containers/freezer/0
   # echo $some_pid > /containers/freezer/0/tasks
   # cat /containers/freezer/0/freezer.state
   RUNNING
   # echo FROZEN > /containers/freezer/0/freezer.state
   # cat /containers/freezer/0/freezer.state
   FREEZING
   # cat /containers/freezer/0/freezer.state
   FROZEN
   # echo RUNNING > /containers/freezer/0/freezer.state
   # cat /containers/freezer/0/freezer.state
   RUNNING
   # echo 9 > /containers/freezer/0/signal.kill
---
 include/asm-alpha/thread_info.h     |    2 ++
 include/asm-avr32/thread_info.h     |    2 ++
 include/asm-cris/thread_info.h      |    2 ++
 include/asm-h8300/thread_info.h     |    2 ++
 include/asm-m68k/thread_info.h      |    1 +
 include/asm-m68knommu/thread_info.h |    2 ++
 include/asm-parisc/thread_info.h    |    2 ++
 include/asm-s390/thread_info.h      |    2 ++
 include/asm-sparc/thread_info.h     |    2 ++
 include/asm-sparc64/thread_info.h   |    2 ++
 include/asm-um/thread_info.h        |    2 ++
 include/asm-v850/thread_info.h      |    2 ++
 include/asm-xtensa/thread_info.h    |    2 ++
 13 files changed, 25 insertions(+)
Index: linux-2.6.25-mm1/include/asm-alpha/thread_info.h
===================================================================
@@ -74,16 +74,18 @@ register struct thread_info *__current_t
 #define TIF_UAC_NOPRINT		5	/* see sysinfo.h */
 #define TIF_UAC_NOFIX		6
 #define TIF_UAC_SIGBUS		7
 #define TIF_MEMDIE		8
 #define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 /* Work to do on interrupt/exception return.  */
 #define _TIF_WORK_MASK		(_TIF_SIGPENDING | _TIF_NEED_RESCHED)
 
 /* Work to do on any return to userspace.  */

Index: linux-2.6.25-mm1/include/asm-avr32/thread_info.h
===================================================================
@@ -86,10 +86,11 @@ static inline struct thread_info *curren
 #define TIF_BREAKPOINT		4	/* enter monitor mode on return */
 #define TIF_SINGLE_STEP		5	/* single step in progress */
 #define TIF_MEMDIE		6
 #define TIF_RESTORE_SIGMASK	7	/* restore signal mask in do_signal */
 #define TIF_CPU_GOING_TO_SLEEP	8	/* CPU is entering sleep 0 mode */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 #define TIF_DEBUG		30	/* debugging enabled */
 #define TIF_USERSPACE		31      /* true if FS sets userspace */
 
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)

@@ -97,10 +98,11 @@ static inline struct thread_info *curren
 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
 #define _TIF_SINGLE_STEP	(1 << TIF_SINGLE_STEP)
 #define _TIF_MEMDIE		(1 << TIF_MEMDIE)
 #define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
 #define _TIF_CPU_GOING_TO_SLEEP (1 << TIF_CPU_GOING_TO_SLEEP)
+#define _TIF_FREEZE		(1 << TIF_FREEZE)
 
 /* Note: The masks below must never span more than 16 bits! */
 
 /* work to do on interrupt/exception return */
 #define _TIF_WORK_MASK				\

Index: linux-2.6.25-mm1/include/asm-cris/thread_info.h
===================================================================
@@ -84,17 +84,19 @@ struct thread_info {
 #define TIF_SIGPENDING		2	/* signal pending */
 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
 #define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal() */
 #define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_MEMDIE		17
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 #define _TIF_ALLWORK_MASK	0x0000FFFF	/* work to do on any return to u-space */
 
 #endif /* __KERNEL__ */

Index: linux-2.6.25-mm1/include/asm-h8300/thread_info.h
===================================================================
@@ -90,17 +90,19 @@ static inline struct thread_info *curren
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling
 					   TIF_NEED_RESCHED */
 #define TIF_MEMDIE		4
 #define TIF_RESTORE_SIGMASK	5	/* restore signal mask in do_signal() */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 
 #endif /* __KERNEL__ */
 

Index: linux-2.6.25-mm1/include/asm-m68k/thread_info.h
===================================================================
@@ -56,7 +56,8 @@ struct thread_info {
 #define TIF_SIGPENDING		6	/* signal pending */
 #define TIF_NEED_RESCHED	7	/* rescheduling necessary */
 #define TIF_DELAYED_TRACE	14	/* single step a syscall */
 #define TIF_SYSCALL_TRACE	15	/* syscall trace active */
 #define TIF_MEMDIE		16
+#define TIF_FREEZE		19
 
 #endif	/* _ASM_M68K_THREAD_INFO_H */

Index: linux-2.6.25-mm1/include/asm-m68knommu/thread_info.h
===================================================================
@@ -86,16 +86,18 @@ static inline struct thread_info *curren
 #define TIF_SIGPENDING		1	/* signal pending */
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling
 					   TIF_NEED_RESCHED */
 #define TIF_MEMDIE		4
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 
 #endif /* __KERNEL__ */
 

Index: linux-2.6.25-mm1/include/asm-parisc/thread_info.h
===================================================================
@@ -60,17 +60,19 @@ struct thread_info {
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_32BIT               4       /* 32 bit binary */
 #define TIF_MEMDIE		5
 #define TIF_RESTORE_SIGMASK	6	/* restore saved signal mask */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
 #define _TIF_32BIT		(1 << TIF_32BIT)
 #define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1 << TIF_FREEZE)
 
 #define _TIF_USER_WORK_MASK     (_TIF_SIGPENDING | \
                                  _TIF_NEED_RESCHED | _TIF_RESTORE_SIGMASK)
 
 #endif /* __KERNEL__ */

Index: linux-2.6.25-mm1/include/asm-s390/thread_info.h
===================================================================
@@ -99,10 +99,11 @@ static inline struct thread_info *curren
 #define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling 
 					   TIF_NEED_RESCHED */
 #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<<TIF_SYSCALL_TRACE)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)

@@ -111,10 +112,11 @@ static inline struct thread_info *curren
 #define _TIF_SINGLE_STEP	(1<<TIF_SINGLE_STEP)
 #define _TIF_MCCK_PENDING	(1<<TIF_MCCK_PENDING)
 #define _TIF_USEDFPU		(1<<TIF_USEDFPU)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_31BIT		(1<<TIF_31BIT)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #endif /* __KERNEL__ */
 
 #define PREEMPT_ACTIVE		0x4000000
 

Index: linux-2.6.25-mm1/include/asm-sparc/thread_info.h
===================================================================
@@ -135,17 +135,19 @@ BTFIXUPDEF_CALL(void, free_thread_info, 
 #define TIF_USEDFPU		8	/* FPU was used by this task
 					 * this quantum (SMP) */
 #define TIF_POLLING_NRFLAG	9	/* true if poll_idle() is polling
 					 * TIF_NEED_RESCHED */
 #define TIF_MEMDIE		10
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_USEDFPU		(1<<TIF_USEDFPU)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #endif /* __KERNEL__ */
 
 #endif /* _ASM_THREAD_INFO_H */

Index: linux-2.6.25-mm1/include/asm-sparc64/thread_info.h
===================================================================
@@ -234,10 +234,11 @@ register struct thread_info *current_thr
  *       an immediate value in instructions such as andcc.
  */
 #define TIF_ABI_PENDING		12
 #define TIF_MEMDIE		13
 #define TIF_POLLING_NRFLAG	14
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_PERFCTR		(1<<TIF_PERFCTR)

@@ -247,10 +248,11 @@ register struct thread_info *current_thr
 #define _TIF_SECCOMP		(1<<TIF_SECCOMP)
 #define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_ABI_PENDING	(1<<TIF_ABI_PENDING)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_USER_WORK_MASK	((0xff << TI_FLAG_WSAVED_SHIFT) | \
 				 (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | \
 				  _TIF_NEED_RESCHED | _TIF_PERFCTR))
 

Index: linux-2.6.25-mm1/include/asm-um/thread_info.h
===================================================================
@@ -81,15 +81,17 @@ static inline struct thread_info *curren
 					 */
 #define TIF_RESTART_BLOCK 	4
 #define TIF_MEMDIE	 	5
 #define TIF_SYSCALL_AUDIT	6
 #define TIF_RESTORE_SIGMASK	7
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG     (1 << TIF_POLLING_NRFLAG)
 #define _TIF_MEMDIE		(1 << TIF_MEMDIE)
 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
 #define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1 << TIF_FREEZE)
 
 #endif

Index: linux-2.6.25-mm1/include/asm-v850/thread_info.h
===================================================================
@@ -80,16 +80,18 @@ struct thread_info {
 #define TIF_SIGPENDING		1	/* signal pending */
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling
 					   TIF_NEED_RESCHED */
 #define TIF_MEMDIE		4
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 
 /* Size of kernel stack for each process.  */
 #define THREAD_SIZE		0x2000
 

Index: linux-2.6.25-mm1/include/asm-xtensa/thread_info.h
===================================================================
@@ -136,18 +136,20 @@ static inline struct thread_info *curren
 #define TIF_SINGLESTEP		3	/* restore singlestep on return to user mode */
 #define TIF_IRET		4	/* return with iret */
 #define TIF_MEMDIE		5
 #define TIF_RESTORE_SIGMASK	6	/* restore signal mask in do_signal() */
 #define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling TIF_NEED_RESCHED */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
 #define _TIF_IRET		(1<<TIF_IRET)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 #define _TIF_ALLWORK_MASK	0x0000FFFF	/* work to do on any return to u-space */
 
 /*

---
 include/asm-alpha/thread_info.h     |    2 ++
 include/asm-avr32/thread_info.h     |    2 ++
 include/asm-cris/thread_info.h      |    2 ++
 include/asm-h8300/thread_info.h     |    2 ++
 include/asm-m68k/thread_info.h      |    1 +
 include/asm-m68knommu/thread_info.h |    2 ++
 include/asm-parisc/thread_info.h    |    2 ++
 include/asm-s390/thread_info.h      |    2 ++
 include/asm-sparc/thread_info.h     |    2 ++
 include/asm-sparc64/thread_info.h   |    2 ++
 include/asm-um/thread_info.h        |    2 ++
 include/asm-v850/thread_info.h      |    2 ++
 include/asm-xtensa/thread_info.h    |    2 ++
 13 files changed, 25 insertions(+)
Index: linux-2.6.25-mm1/include/asm-alpha/thread_info.h
===================================================================
@@ -74,16 +74,18 @@ register struct thread_info *__current_t
 #define TIF_UAC_NOPRINT		5	/* see sysinfo.h */
 #define TIF_UAC_NOFIX		6
 #define TIF_UAC_SIGBUS		7
 #define TIF_MEMDIE		8
 #define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 /* Work to do on interrupt/exception return.  */
 #define _TIF_WORK_MASK		(_TIF_SIGPENDING | _TIF_NEED_RESCHED)
 
 /* Work to do on any return to userspace.  */

Index: linux-2.6.25-mm1/include/asm-avr32/thread_info.h
===================================================================
@@ -86,10 +86,11 @@ static inline struct thread_info *curren
 #define TIF_BREAKPOINT		4	/* enter monitor mode on return */
 #define TIF_SINGLE_STEP		5	/* single step in progress */
 #define TIF_MEMDIE		6
 #define TIF_RESTORE_SIGMASK	7	/* restore signal mask in do_signal */
 #define TIF_CPU_GOING_TO_SLEEP	8	/* CPU is entering sleep 0 mode */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 #define TIF_DEBUG		30	/* debugging enabled */
 #define TIF_USERSPACE		31      /* true if FS sets userspace */
 
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)

@@ -97,10 +98,11 @@ static inline struct thread_info *curren
 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
 #define _TIF_SINGLE_STEP	(1 << TIF_SINGLE_STEP)
 #define _TIF_MEMDIE		(1 << TIF_MEMDIE)
 #define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
 #define _TIF_CPU_GOING_TO_SLEEP (1 << TIF_CPU_GOING_TO_SLEEP)
+#define _TIF_FREEZE		(1 << TIF_FREEZE)
 
 /* Note: The masks below must never span more than 16 bits! */
 
 /* work to do on interrupt/exception return */
 #define _TIF_WORK_MASK				\

Index: linux-2.6.25-mm1/include/asm-cris/thread_info.h
===================================================================
@@ -84,17 +84,19 @@ struct thread_info {
 #define TIF_SIGPENDING		2	/* signal pending */
 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
 #define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal() */
 #define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_MEMDIE		17
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 #define _TIF_ALLWORK_MASK	0x0000FFFF	/* work to do on any return to u-space */
 
 #endif /* __KERNEL__ */

Index: linux-2.6.25-mm1/include/asm-h8300/thread_info.h
===================================================================
@@ -90,17 +90,19 @@ static inline struct thread_info *curren
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling
 					   TIF_NEED_RESCHED */
 #define TIF_MEMDIE		4
 #define TIF_RESTORE_SIGMASK	5	/* restore signal mask in do_signal() */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 
 #endif /* __KERNEL__ */
 

Index: linux-2.6.25-mm1/include/asm-m68k/thread_info.h
===================================================================
@@ -56,7 +56,8 @@ struct thread_info {
 #define TIF_SIGPENDING		6	/* signal pending */
 #define TIF_NEED_RESCHED	7	/* rescheduling necessary */
 #define TIF_DELAYED_TRACE	14	/* single step a syscall */
 #define TIF_SYSCALL_TRACE	15	/* syscall trace active */
 #define TIF_MEMDIE		16
+#define TIF_FREEZE		19
 
 #endif	/* _ASM_M68K_THREAD_INFO_H */

Index: linux-2.6.25-mm1/include/asm-m68knommu/thread_info.h
===================================================================
@@ -86,16 +86,18 @@ static inline struct thread_info *curren
 #define TIF_SIGPENDING		1	/* signal pending */
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling
 					   TIF_NEED_RESCHED */
 #define TIF_MEMDIE		4
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 
 #endif /* __KERNEL__ */
 

Index: linux-2.6.25-mm1/include/asm-parisc/thread_info.h
===================================================================
@@ -60,17 +60,19 @@ struct thread_info {
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_32BIT               4       /* 32 bit binary */
 #define TIF_MEMDIE		5
 #define TIF_RESTORE_SIGMASK	6	/* restore saved signal mask */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
 #define _TIF_32BIT		(1 << TIF_32BIT)
 #define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1 << TIF_FREEZE)
 
 #define _TIF_USER_WORK_MASK     (_TIF_SIGPENDING | \
                                  _TIF_NEED_RESCHED | _TIF_RESTORE_SIGMASK)
 
 #endif /* __KERNEL__ */

Index: linux-2.6.25-mm1/include/asm-s390/thread_info.h
===================================================================
@@ -99,10 +99,11 @@ static inline struct thread_info *curren
 #define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling 
 					   TIF_NEED_RESCHED */
 #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<<TIF_SYSCALL_TRACE)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)

@@ -111,10 +112,11 @@ static inline struct thread_info *curren
 #define _TIF_SINGLE_STEP	(1<<TIF_SINGLE_STEP)
 #define _TIF_MCCK_PENDING	(1<<TIF_MCCK_PENDING)
 #define _TIF_USEDFPU		(1<<TIF_USEDFPU)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_31BIT		(1<<TIF_31BIT)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #endif /* __KERNEL__ */
 
 #define PREEMPT_ACTIVE		0x4000000
 

Index: linux-2.6.25-mm1/include/asm-sparc/thread_info.h
===================================================================
@@ -135,17 +135,19 @@ BTFIXUPDEF_CALL(void, free_thread_info, 
 #define TIF_USEDFPU		8	/* FPU was used by this task
 					 * this quantum (SMP) */
 #define TIF_POLLING_NRFLAG	9	/* true if poll_idle() is polling
 					 * TIF_NEED_RESCHED */
 #define TIF_MEMDIE		10
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_USEDFPU		(1<<TIF_USEDFPU)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #endif /* __KERNEL__ */
 
 #endif /* _ASM_THREAD_INFO_H */

Index: linux-2.6.25-mm1/include/asm-sparc64/thread_info.h
===================================================================
@@ -234,10 +234,11 @@ register struct thread_info *current_thr
  *       an immediate value in instructions such as andcc.
  */
 #define TIF_ABI_PENDING		12
 #define TIF_MEMDIE		13
 #define TIF_POLLING_NRFLAG	14
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_PERFCTR		(1<<TIF_PERFCTR)

@@ -247,10 +248,11 @@ register struct thread_info *current_thr
 #define _TIF_SECCOMP		(1<<TIF_SECCOMP)
 #define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_ABI_PENDING	(1<<TIF_ABI_PENDING)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_USER_WORK_MASK	((0xff << TI_FLAG_WSAVED_SHIFT) | \
 				 (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | \
 				  _TIF_NEED_RESCHED | _TIF_PERFCTR))
 

Index: linux-2.6.25-mm1/include/asm-um/thread_info.h
===================================================================
@@ -81,15 +81,17 @@ static inline struct thread_info *curren
 					 */
 #define TIF_RESTART_BLOCK 	4
 #define TIF_MEMDIE	 	5
 #define TIF_SYSCALL_AUDIT	6
 #define TIF_RESTORE_SIGMASK	7
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG     (1 << TIF_POLLING_NRFLAG)
 #define _TIF_MEMDIE		(1 << TIF_MEMDIE)
 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
 #define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1 << TIF_FREEZE)
 
 #endif

Index: linux-2.6.25-mm1/include/asm-v850/thread_info.h
===================================================================
@@ -80,16 +80,18 @@ struct thread_info {
 #define TIF_SIGPENDING		1	/* signal pending */
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling
 					   TIF_NEED_RESCHED */
 #define TIF_MEMDIE		4
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 
 /* Size of kernel stack for each process.  */
 #define THREAD_SIZE		0x2000
 

Index: linux-2.6.25-mm1/include/asm-xtensa/thread_info.h
===================================================================
@@ -136,18 +136,20 @@ static inline struct thread_info *curren
 #define TIF_SINGLESTEP		3	/* restore singlestep on return to user mode */
 #define TIF_IRET		4	/* return with iret */
 #define TIF_MEMDIE		5
 #define TIF_RESTORE_SIGMASK	6	/* restore signal mask in do_signal() */
 #define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling TIF_NEED_RESCHED */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
 #define _TIF_IRET		(1<<TIF_IRET)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 #define _TIF_ALLWORK_MASK	0x0000FFFF	/* work to do on any return to u-space */
 
 /*

	Merged Roland's "STOPPED is frozen enough" changes. For details see:
		http://lkml.org/lkml/2008/3/3/676
 include/linux/freezer.h |   19 ++-----
 kernel/Makefile         |    4 -
 kernel/freezer.c        |  124 ++++++++++++++++++++++++++++++++++++++++++++++++
 kernel/power/process.c  |  113 -------------------------------------------
 4 files changed, 133 insertions(+), 127 deletions(-)
Index: linux-2.6.25-mm1/include/linux/freezer.h
===================================================================
@@ -4,11 +4,10 @@
 #define FREEZER_H_INCLUDED
 
 #include <linux/sched.h>
 #include <linux/wait.h>
 
-#ifdef CONFIG_PM_SLEEP
 /*
  * Check if a process has been frozen
  */
 static inline int frozen(struct task_struct *p)
 {

@@ -61,22 +60,27 @@ static inline int thaw_process(struct ta
 	task_unlock(p);
 	return 0;
 }
 
 extern void refrigerator(void);
-extern int freeze_processes(void);
-extern void thaw_processes(void);
 
 static inline int try_to_freeze(void)
 {
 	if (freezing(current)) {
 		refrigerator();
 		return 1;
 	} else
 		return 0;
 }
 
+extern int freeze_task(struct task_struct *p, int with_mm_only);
+
+#ifdef CONFIG_PM_SLEEP
+
+extern int freeze_processes(void);
+extern void thaw_processes(void);
+
 /*
  * The PF_FREEZER_SKIP flag should be set by a vfork parent right before it
  * calls wait_for_completion(&vfork) and reset right after it returns from this
  * function.  Next, the parent should call try_to_freeze() to freeze itself
  * appropriately in case the child has exited before the freezing of tasks is

@@ -156,22 +160,13 @@ static inline void set_freezable(void)
 				__retval); 				\
 	} while (try_to_freeze());					\
 	__retval;							\
 })
 #else /* !CONFIG_PM_SLEEP */
-static inline int frozen(struct task_struct *p) { return 0; }
-static inline int freezing(struct task_struct *p) { return 0; }
-static inline void set_freeze_flag(struct task_struct *p) {}
-static inline void clear_freeze_flag(struct task_struct *p) {}
-static inline int thaw_process(struct task_struct *p) { return 1; }
-
-static inline void refrigerator(void) {}
 static inline int freeze_processes(void) { BUG(); return 0; }
 static inline void thaw_processes(void) {}
 
-static inline int try_to_freeze(void) { return 0; }
-
 static inline void freezer_do_not_count(void) {}
 static inline void freezer_count(void) {}
 static inline int freezer_should_skip(struct task_struct *p) { return 0; }
 static inline void set_freezable(void) {}
 

Index: linux-2.6.25-mm1/kernel/Makefile
===================================================================
@@ -3,15 +3,15 @@
 #
 
 obj-y     = sched.o fork.o exec_domain.o panic.o printk.o profile.o \
 	    exit.o itimer.o time.o softirq.o resource.o \
 	    sysctl.o capability.o ptrace.o timer.o user.o \
-	    signal.o sys.o kmod.o workqueue.o pid.o \
+	    signal.o sys.o kmod.o workqueue.o pid.o freezer.o \
 	    rcupdate.o extable.o params.o posix-timers.o \
 	    kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
 	    hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
-	    notifier.o ksysfs.o pm_qos_params.o
+	    notifier.o ksysfs.o pm_qos_params.o
 
 ifdef CONFIG_FTRACE
 # Do not profile debug utilities
 ORIG_CFLAGS := $(KBUILD_CFLAGS)
 KBUILD_CFLAGS = $(if $(filter-out lockdep% %debug,$(basename $(notdir $@))), \

---
 include/asm-alpha/thread_info.h     |    2 ++
 include/asm-avr32/thread_info.h     |    2 ++
 include/asm-cris/thread_info.h      |    2 ++
 include/asm-h8300/thread_info.h     |    2 ++
 include/asm-m68k/thread_info.h      |    1 +
 include/asm-m68knommu/thread_info.h |    2 ++
 include/asm-parisc/thread_info.h    |    2 ++
 include/asm-s390/thread_info.h      |    2 ++
 include/asm-sparc/thread_info.h     |    2 ++
 include/asm-sparc64/thread_info.h   |    2 ++
 include/asm-um/thread_info.h        |    2 ++
 include/asm-v850/thread_info.h      |    2 ++
 include/asm-xtensa/thread_info.h    |    2 ++
 13 files changed, 25 insertions(+)
Index: linux-2.6.25-mm1/include/asm-alpha/thread_info.h
===================================================================
@@ -74,16 +74,18 @@ register struct thread_info *__current_t
 #define TIF_UAC_NOPRINT		5	/* see sysinfo.h */
 #define TIF_UAC_NOFIX		6
 #define TIF_UAC_SIGBUS		7
 #define TIF_MEMDIE		8
 #define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 /* Work to do on interrupt/exception return.  */
 #define _TIF_WORK_MASK		(_TIF_SIGPENDING | _TIF_NEED_RESCHED)
 
 /* Work to do on any return to userspace.  */

Index: linux-2.6.25-mm1/include/asm-avr32/thread_info.h
===================================================================
@@ -86,10 +86,11 @@ static inline struct thread_info *curren
 #define TIF_BREAKPOINT		4	/* enter monitor mode on return */
 #define TIF_SINGLE_STEP		5	/* single step in progress */
 #define TIF_MEMDIE		6
 #define TIF_RESTORE_SIGMASK	7	/* restore signal mask in do_signal */
 #define TIF_CPU_GOING_TO_SLEEP	8	/* CPU is entering sleep 0 mode */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 #define TIF_DEBUG		30	/* debugging enabled */
 #define TIF_USERSPACE		31      /* true if FS sets userspace */
 
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)

@@ -97,10 +98,11 @@ static inline struct thread_info *curren
 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
 #define _TIF_SINGLE_STEP	(1 << TIF_SINGLE_STEP)
 #define _TIF_MEMDIE		(1 << TIF_MEMDIE)
 #define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
 #define _TIF_CPU_GOING_TO_SLEEP (1 << TIF_CPU_GOING_TO_SLEEP)
+#define _TIF_FREEZE		(1 << TIF_FREEZE)
 
 /* Note: The masks below must never span more than 16 bits! */
 
 /* work to do on interrupt/exception return */
 #define _TIF_WORK_MASK				\

Index: linux-2.6.25-mm1/include/asm-cris/thread_info.h
===================================================================
@@ -84,17 +84,19 @@ struct thread_info {
 #define TIF_SIGPENDING		2	/* signal pending */
 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
 #define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal() */
 #define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_MEMDIE		17
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 #define _TIF_ALLWORK_MASK	0x0000FFFF	/* work to do on any return to u-space */
 
 #endif /* __KERNEL__ */

Index: linux-2.6.25-mm1/include/asm-h8300/thread_info.h
===================================================================
@@ -90,17 +90,19 @@ static inline struct thread_info *curren
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling
 					   TIF_NEED_RESCHED */
 #define TIF_MEMDIE		4
 #define TIF_RESTORE_SIGMASK	5	/* restore signal mask in do_signal() */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 
 #endif /* __KERNEL__ */
 

Index: linux-2.6.25-mm1/include/asm-m68k/thread_info.h
===================================================================
@@ -56,7 +56,8 @@ struct thread_info {
 #define TIF_SIGPENDING		6	/* signal pending */
 #define TIF_NEED_RESCHED	7	/* rescheduling necessary */
 #define TIF_DELAYED_TRACE	14	/* single step a syscall */
 #define TIF_SYSCALL_TRACE	15	/* syscall trace active */
 #define TIF_MEMDIE		16
+#define TIF_FREEZE		19
 
 #endif	/* _ASM_M68K_THREAD_INFO_H */

Index: linux-2.6.25-mm1/include/asm-m68knommu/thread_info.h
===================================================================
@@ -86,16 +86,18 @@ static inline struct thread_info *curren
 #define TIF_SIGPENDING		1	/* signal pending */
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling
 					   TIF_NEED_RESCHED */
 #define TIF_MEMDIE		4
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 
 #endif /* __KERNEL__ */
 

Index: linux-2.6.25-mm1/include/asm-parisc/thread_info.h
===================================================================
@@ -60,17 +60,19 @@ struct thread_info {
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_32BIT               4       /* 32 bit binary */
 #define TIF_MEMDIE		5
 #define TIF_RESTORE_SIGMASK	6	/* restore saved signal mask */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
 #define _TIF_32BIT		(1 << TIF_32BIT)
 #define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1 << TIF_FREEZE)
 
 #define _TIF_USER_WORK_MASK     (_TIF_SIGPENDING | \
                                  _TIF_NEED_RESCHED | _TIF_RESTORE_SIGMASK)
 
 #endif /* __KERNEL__ */

Index: linux-2.6.25-mm1/include/asm-s390/thread_info.h
===================================================================
@@ -99,10 +99,11 @@ static inline struct thread_info *curren
 #define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling 
 					   TIF_NEED_RESCHED */
 #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<<TIF_SYSCALL_TRACE)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)

@@ -111,10 +112,11 @@ static inline struct thread_info *curren
 #define _TIF_SINGLE_STEP	(1<<TIF_SINGLE_STEP)
 #define _TIF_MCCK_PENDING	(1<<TIF_MCCK_PENDING)
 #define _TIF_USEDFPU		(1<<TIF_USEDFPU)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_31BIT		(1<<TIF_31BIT)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #endif /* __KERNEL__ */
 
 #define PREEMPT_ACTIVE		0x4000000
 

Index: linux-2.6.25-mm1/include/asm-sparc/thread_info.h
===================================================================
@@ -135,17 +135,19 @@ BTFIXUPDEF_CALL(void, free_thread_info, 
 #define TIF_USEDFPU		8	/* FPU was used by this task
 					 * this quantum (SMP) */
 #define TIF_POLLING_NRFLAG	9	/* true if poll_idle() is polling
 					 * TIF_NEED_RESCHED */
 #define TIF_MEMDIE		10
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_USEDFPU		(1<<TIF_USEDFPU)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #endif /* __KERNEL__ */
 
 #endif /* _ASM_THREAD_INFO_H */

Index: linux-2.6.25-mm1/include/asm-sparc64/thread_info.h
===================================================================
@@ -234,10 +234,11 @@ register struct thread_info *current_thr
  *       an immediate value in instructions such as andcc.
  */
 #define TIF_ABI_PENDING		12
 #define TIF_MEMDIE		13
 #define TIF_POLLING_NRFLAG	14
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_PERFCTR		(1<<TIF_PERFCTR)

@@ -247,10 +248,11 @@ register struct thread_info *current_thr
 #define _TIF_SECCOMP		(1<<TIF_SECCOMP)
 #define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
 #define _TIF_ABI_PENDING	(1<<TIF_ABI_PENDING)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_USER_WORK_MASK	((0xff << TI_FLAG_WSAVED_SHIFT) | \
 				 (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | \
 				  _TIF_NEED_RESCHED | _TIF_PERFCTR))
 

Index: linux-2.6.25-mm1/include/asm-um/thread_info.h
===================================================================
@@ -81,15 +81,17 @@ static inline struct thread_info *curren
 					 */
 #define TIF_RESTART_BLOCK 	4
 #define TIF_MEMDIE	 	5
 #define TIF_SYSCALL_AUDIT	6
 #define TIF_RESTORE_SIGMASK	7
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG     (1 << TIF_POLLING_NRFLAG)
 #define _TIF_MEMDIE		(1 << TIF_MEMDIE)
 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
 #define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1 << TIF_FREEZE)
 
 #endif

Index: linux-2.6.25-mm1/include/asm-v850/thread_info.h
===================================================================
@@ -80,16 +80,18 @@ struct thread_info {
 #define TIF_SIGPENDING		1	/* signal pending */
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling
 					   TIF_NEED_RESCHED */
 #define TIF_MEMDIE		4
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 
 /* Size of kernel stack for each process.  */
 #define THREAD_SIZE		0x2000
 

Index: linux-2.6.25-mm1/include/asm-xtensa/thread_info.h
===================================================================
@@ -136,18 +136,20 @@ static inline struct thread_info *curren
 #define TIF_SINGLESTEP		3	/* restore singlestep on return to user mode */
 #define TIF_IRET		4	/* return with iret */
 #define TIF_MEMDIE		5
 #define TIF_RESTORE_SIGMASK	6	/* restore signal mask in do_signal() */
 #define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling TIF_NEED_RESCHED */
+#define TIF_FREEZE		19	/* is freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
 #define _TIF_IRET		(1<<TIF_IRET)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
+#define _TIF_FREEZE		(1<<TIF_FREEZE)
 
 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
 #define _TIF_ALLWORK_MASK	0x0000FFFF	/* work to do on any return to u-space */
 
 /*

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 include/linux/cgroup_freezer.h |   65 +++++++++
 include/linux/cgroup_subsys.h  |    6 
 init/Kconfig                   |    7 +
 kernel/Makefile                |    1 
 kernel/cgroup_freezer.c        |  276 +++++++++++++++++++++++++++++++++++++++++
 kernel/freezer.c               |    1 
 6 files changed, 356 insertions(+)
Index: linux-2.6.25-mm1/include/linux/cgroup_freezer.h
===================================================================
@@ -0,0 +1,65 @@
+#ifndef _LINUX_CGROUP_FREEZER_H
+#define _LINUX_CGROUP_FREEZER_H
+/*
+ * cgroup_freezer.h -  control group freezer subsystem interface
+ *
+ * Copyright IBM Corporation, 2007
+ *
+ * Author : Cedric Le Goater <clg-NmTC/[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#include <linux/cgroup.h>
+
+#ifdef CONFIG_CGROUP_FREEZER
+
+enum freezer_state {
+	STATE_RUNNING = 0,
+	STATE_FREEZING,
+	STATE_FROZEN,
+};
+
+struct freezer {
+	struct cgroup_subsys_state css;
+	enum freezer_state state;
+	spinlock_t lock;
+};
+
+static inline struct freezer *cgroup_freezer(
+		struct cgroup *cgroup)
+{
+	return container_of(
+		cgroup_subsys_state(cgroup, freezer_subsys_id),
+		struct freezer, css);
+}
+
+static inline int cgroup_frozen(struct task_struct *task)
+{
+	struct cgroup *cgroup = task_cgroup(task, freezer_subsys_id);
+	struct freezer *freezer = cgroup_freezer(cgroup);
+	enum freezer_state state;
+
+	spin_lock(&freezer->lock);
+	state = freezer->state;
+	spin_unlock(&freezer->lock);
+
+	return (state == STATE_FROZEN);
+}
+
+#else /* !CONFIG_CGROUP_FREEZER */
+
+static inline int cgroup_frozen(struct task_struct *task)
+{
+	return 0;
+}
+
+#endif /* !CONFIG_CGROUP_FREEZER */
+
+#endif /* _LINUX_CGROUP_FREEZER_H */

Index: linux-2.6.25-mm1/include/linux/cgroup_subsys.h
===================================================================
@@ -46,5 +46,11 @@ SUBSYS(mem_cgroup)
 #ifdef CONFIG_CGROUP_DEVICE
 SUBSYS(devices)
 #endif
 
 /* */
+
+#ifdef CONFIG_CGROUP_FREEZER
+SUBSYS(freezer)
+#endif
+
+/* */

Index: linux-2.6.25-mm1/init/Kconfig
===================================================================
@@ -321,10 +321,17 @@ config GROUP_SCHED
 	default y
 	help
 	  This feature lets CPU scheduler recognize task groups and control CPU
 	  bandwidth allocation to such task groups.
 
+config CGROUP_FREEZER
+        bool "control group freezer subsystem"
+        depends on CGROUPS
+        help
+          Provides a way to freeze and unfreeze all tasks in a
+	  cgroup
+
 config FAIR_GROUP_SCHED
 	bool "Group scheduling for SCHED_OTHER"
 	depends on GROUP_SCHED
 	default y
 

Index: linux-2.6.25-mm1/kernel/Makefile
===================================================================
@@ -46,10 +46,11 @@ obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
 obj-$(CONFIG_KEXEC) += kexec.o
 obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
 obj-$(CONFIG_COMPAT) += compat.o
 obj-$(CONFIG_CGROUPS) += cgroup.o
 obj-$(CONFIG_CGROUP_DEBUG) += cgroup_debug.o
+obj-$(CONFIG_CGROUP_FREEZER) += cgroup_freezer.o
 obj-$(CONFIG_CPUSETS) += cpuset.o
 obj-$(CONFIG_CGROUP_NS) += ns_cgroup.o
 obj-$(CONFIG_UTS_NS) += utsname.o
 obj-$(CONFIG_USER_NS) += user_namespace.o
 obj-$(CONFIG_PID_NS) += pid_namespace.o

Index: linux-2.6.25-mm1/kernel/freezer.c
===================================================================
@@ -120,5 +120,6 @@ int freeze_task(struct task_struct *p, i
 		}
 	}
 	task_unlock(p);
 	return ret;
 }
+EXPORT_SYMBOL(freeze_task);

	Merged Roland's "STOPPED is frozen enough" changes. For details see:
		http://lkml.org/lkml/2008/3/3/676
 include/linux/freezer.h |   19 ++-----
 kernel/Makefile         |    4 -
 kernel/freezer.c        |  124 ++++++++++++++++++++++++++++++++++++++++++++++++
 kernel/power/process.c  |  113 -------------------------------------------
 4 files changed, 133 insertions(+), 127 deletions(-)
Index: linux-2.6.25-mm1/include/linux/freezer.h
===================================================================
@@ -4,11 +4,10 @@
 #define FREEZER_H_INCLUDED
 
 #include <linux/sched.h>
 #include <linux/wait.h>
 
-#ifdef CONFIG_PM_SLEEP
 /*
  * Check if a process has been frozen
  */
 static inline int frozen(struct task_struct *p)
 {

@@ -61,22 +60,27 @@ static inline int thaw_process(struct ta
 	task_unlock(p);
 	return 0;
 }
 
 extern void refrigerator(void);
-extern int freeze_processes(void);
-extern void thaw_processes(void);
 
 static inline int try_to_freeze(void)
 {
 	if (freezing(current)) {
 		refrigerator();
 		return 1;
 	} else
 		return 0;
 }
 
+extern int freeze_task(struct task_struct *p, int with_mm_only);
+
+#ifdef CONFIG_PM_SLEEP
+
+extern int freeze_processes(void);
+extern void thaw_processes(void);
+
 /*
  * The PF_FREEZER_SKIP flag should be set by a vfork parent right before it
  * calls wait_for_completion(&vfork) and reset right after it returns from this
  * function.  Next, the parent should call try_to_freeze() to freeze itself
  * appropriately in case the child has exited before the freezing of tasks is

@@ -156,22 +160,13 @@ static inline void set_freezable(void)
 				__retval); 				\
 	} while (try_to_freeze());					\
 	__retval;							\
 })
 #else /* !CONFIG_PM_SLEEP */
-static inline int frozen(struct task_struct *p) { return 0; }
-static inline int freezing(struct task_struct *p) { return 0; }
-static inline void set_freeze_flag(struct task_struct *p) {}
-static inline void clear_freeze_flag(struct task_struct *p) {}
-static inline int thaw_process(struct task_struct *p) { return 1; }
-
-static inline void refrigerator(void) {}
 static inline int freeze_processes(void) { BUG(); return 0; }
 static inline void thaw_processes(void) {}
 
-static inline int try_to_freeze(void) { return 0; }
-
 static inline void freezer_do_not_count(void) {}
 static inline void freezer_count(void) {}
 static inline int freezer_should_skip(struct task_struct *p) { return 0; }
 static inline void set_freezable(void) {}
 

Index: linux-2.6.25-mm1/kernel/Makefile
===================================================================
@@ -3,15 +3,15 @@
 #
 
 obj-y     = sched.o fork.o exec_domain.o panic.o printk.o profile.o \
 	    exit.o itimer.o time.o softirq.o resource.o \
 	    sysctl.o capability.o ptrace.o timer.o user.o \
-	    signal.o sys.o kmod.o workqueue.o pid.o \
+	    signal.o sys.o kmod.o workqueue.o pid.o freezer.o \
 	    rcupdate.o extable.o params.o posix-timers.o \
 	    kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
 	    hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
-	    notifier.o ksysfs.o pm_qos_params.o
+	    notifier.o ksysfs.o pm_qos_params.o
 
 ifdef CONFIG_FTRACE
 # Do not profile debug utilities
 ORIG_CFLAGS := $(KBUILD_CFLAGS)
 KBUILD_CFLAGS = $(if $(filter-out lockdep% %debug,$(basename $(notdir $@))), \

---
 kernel/power/process.c |    4 ++++
 1 file changed, 4 insertions(+)
Index: linux-2.6.25-mm1/kernel/power/process.c
===================================================================
@@ -11,10 +11,11 @@
 #include <linux/interrupt.h>
 #include <linux/suspend.h>
 #include <linux/module.h>
 #include <linux/syscalls.h>
 #include <linux/freezer.h>
+#include <linux/cgroup_freezer.h>
 
 /* 
  * Timeout for stopping processes
  */
 #define TIMEOUT	(20 * HZ)

@@ -150,10 +151,13 @@ static void thaw_tasks(int thaw_user_spa
 			continue;
 
 		if (!p->mm == thaw_user_space)
 			continue;
 
+		if (cgroup_frozen(p))
+			continue;
+
 		thaw_process(p);
 	} while_each_thread(g, p);
 	read_unlock(&tasklist_lock);
 }
 

	Merged Roland's "STOPPED is frozen enough" changes. For details see:
		http://lkml.org/lkml/2008/3/3/676
 include/linux/freezer.h |   19 ++-----
 kernel/Makefile         |    4 -
 kernel/freezer.c        |  124 ++++++++++++++++++++++++++++++++++++++++++++++++
 kernel/power/process.c  |  113 -------------------------------------------
 4 files changed, 133 insertions(+), 127 deletions(-)
Index: linux-2.6.25-mm1/include/linux/freezer.h
===================================================================
@@ -4,11 +4,10 @@
 #define FREEZER_H_INCLUDED
 
 #include <linux/sched.h>
 #include <linux/wait.h>
 
-#ifdef CONFIG_PM_SLEEP
 /*
  * Check if a process has been frozen
  */
 static inline int frozen(struct task_struct *p)
 {

@@ -61,22 +60,27 @@ static inline int thaw_process(struct ta
 	task_unlock(p);
 	return 0;
 }
 
 extern void refrigerator(void);
-extern int freeze_processes(void);
-extern void thaw_processes(void);
 
 static inline int try_to_freeze(void)
 {
 	if (freezing(current)) {
 		refrigerator();
 		return 1;
 	} else
 		return 0;
 }
 
+extern int freeze_task(struct task_struct *p, int with_mm_only);
+
+#ifdef CONFIG_PM_SLEEP
+
+extern int freeze_processes(void);
+extern void thaw_processes(void);
+
 /*
  * The PF_FREEZER_SKIP flag should be set by a vfork parent right before it
  * calls wait_for_completion(&vfork) and reset right after it returns from this
  * function.  Next, the parent should call try_to_freeze() to freeze itself
  * appropriately in case the child has exited before the freezing of tasks is

@@ -156,22 +160,13 @@ static inline void set_freezable(void)
 				__retval); 				\
 	} while (try_to_freeze());					\
 	__retval;							\
 })
 #else /* !CONFIG_PM_SLEEP */
-static inline int frozen(struct task_struct *p) { return 0; }
-static inline int freezing(struct task_struct *p) { return 0; }
-static inline void set_freeze_flag(struct task_struct *p) {}
-static inline void clear_freeze_flag(struct task_struct *p) {}
-static inline int thaw_process(struct task_struct *p) { return 1; }
-
-static inline void refrigerator(void) {}
 static inline int freeze_processes(void) { BUG(); return 0; }
 static inline void thaw_processes(void) {}
 
-static inline int try_to_freeze(void) { return 0; }
-
 static inline void freezer_do_not_count(void) {}
 static inline void freezer_count(void) {}
 static inline int freezer_should_skip(struct task_struct *p) { return 0; }
 static inline void set_freezable(void) {}
 

Index: linux-2.6.25-mm1/kernel/Makefile
===================================================================
@@ -3,15 +3,15 @@
 #
 
 obj-y     = sched.o fork.o exec_domain.o panic.o printk.o profile.o \
 	    exit.o itimer.o time.o softirq.o resource.o \
 	    sysctl.o capability.o ptrace.o timer.o user.o \
-	    signal.o sys.o kmod.o workqueue.o pid.o \
+	    signal.o sys.o kmod.o workqueue.o pid.o freezer.o \
 	    rcupdate.o extable.o params.o posix-timers.o \
 	    kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
 	    hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
-	    notifier.o ksysfs.o pm_qos_params.o
+	    notifier.o ksysfs.o pm_qos_params.o
 
 ifdef CONFIG_FTRACE
 # Do not profile debug utilities
 ORIG_CFLAGS := $(KBUILD_CFLAGS)
 KBUILD_CFLAGS = $(if $(filter-out lockdep% %debug,$(basename $(notdir $@))), \

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---
 include/linux/freezer.h |   10 ++++
 include/linux/sched.h   |    1 
 kernel/kthread.c        |    2 
 kernel/power/process.c  |   97 ++++++++++++++++++++----------------------------
 4 files changed, 54 insertions(+), 56 deletions(-)
Index: linux-2.6/include/linux/freezer.h
===================================================================
@@ -128,6 +128,15 @@ static inline void set_freezable(void)
 }
 
 /*
+ * Tell the freezer that the current task should be frozen by it and that it
+ * should send a fake signal to the task to freeze it.
+ */
+static inline void set_freezable_with_signal(void)
+{
+	current->flags &= ~(PF_NOFREEZE | PF_FREEZER_NOSIG);
+}
+
+/*
  * Freezer-friendly wrappers around wait_event_interruptible() and
  * wait_event_interruptible_timeout(), originally defined in <linux/wait.h>
  */

@@ -174,6 +183,7 @@ static inline void freezer_do_not_count(
 static inline void freezer_count(void) {}
 static inline int freezer_should_skip(struct task_struct *p) { return 0; }
 static inline void set_freezable(void) {}
+static inline void set_freezable_with_signal(void) {}
 
 #define wait_event_freezable(wq, condition)				\
 		wait_event_interruptible(wq, condition)

Index: linux-2.6/include/linux/sched.h
===================================================================
@@ -1499,6 +1499,7 @@ static inline void put_task_struct(struc
 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
+#define PF_FREEZER_NOSIG 0x80000000	/* Freezer won't send signals to it */
 
 /*
  * Only the _current_ task can read/write to tsk->flags, but other

Index: linux-2.6/kernel/kthread.c
===================================================================
@@ -234,7 +234,7 @@ int kthreadd(void *unused)
 	set_user_nice(tsk, KTHREAD_NICE_LEVEL);
 	set_cpus_allowed(tsk, CPU_MASK_ALL);
 
-	current->flags |= PF_NOFREEZE;
+	current->flags |= PF_NOFREEZE | PF_FREEZER_NOSIG;
 
 	for (;;) {
 		set_current_state(TASK_INTERRUPTIBLE);

---
 include/linux/freezer.h |   10 ++++
 include/linux/sched.h   |    1 
 kernel/kthread.c        |    2 
 kernel/power/process.c  |   97 ++++++++++++++++++++----------------------------
 4 files changed, 54 insertions(+), 56 deletions(-)
Index: linux-2.6/include/linux/freezer.h
===================================================================
@@ -128,6 +128,15 @@ static inline void set_freezable(void)
 }
 
 /*
+ * Tell the freezer that the current task should be frozen by it and that it
+ * should send a fake signal to the task to freeze it.
+ */
+static inline void set_freezable_with_signal(void)
+{
+	current->flags &= ~(PF_NOFREEZE | PF_FREEZER_NOSIG);
+}
+
+/*
  * Freezer-friendly wrappers around wait_event_interruptible() and
  * wait_event_interruptible_timeout(), originally defined in <linux/wait.h>
  */

@@ -174,6 +183,7 @@ static inline void freezer_do_not_count(
 static inline void freezer_count(void) {}
 static inline int freezer_should_skip(struct task_struct *p) { return 0; }
 static inline void set_freezable(void) {}
+static inline void set_freezable_with_signal(void) {}
 
 #define wait_event_freezable(wq, condition)				\
 		wait_event_interruptible(wq, condition)

Index: linux-2.6/include/linux/sched.h
===================================================================
@@ -1499,6 +1499,7 @@ static inline void put_task_struct(struc
 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
+#define PF_FREEZER_NOSIG 0x80000000	/* Freezer won't send signals to it */
 
 /*
  * Only the _current_ task can read/write to tsk->flags, but other

Index: linux-2.6/kernel/kthread.c
===================================================================
@@ -234,7 +234,7 @@ int kthreadd(void *unused)
 	set_user_nice(tsk, KTHREAD_NICE_LEVEL);
 	set_cpus_allowed(tsk, CPU_MASK_ALL);
 
-	current->flags |= PF_NOFREEZE;
+	current->flags |= PF_NOFREEZE | PF_FREEZER_NOSIG;
 
 	for (;;) {
 		set_current_state(TASK_INTERRUPTIBLE);

---
 include/linux/freezer.h |   10 ++++
 include/linux/sched.h   |    1 
 kernel/kthread.c        |    2 
 kernel/power/process.c  |   97 ++++++++++++++++++++----------------------------
 4 files changed, 54 insertions(+), 56 deletions(-)
Index: linux-2.6/include/linux/freezer.h
===================================================================
@@ -128,6 +128,15 @@ static inline void set_freezable(void)
 }
 
 /*
+ * Tell the freezer that the current task should be frozen by it and that it
+ * should send a fake signal to the task to freeze it.
+ */
+static inline void set_freezable_with_signal(void)
+{
+	current->flags &= ~(PF_NOFREEZE | PF_FREEZER_NOSIG);
+}
+
+/*
  * Freezer-friendly wrappers around wait_event_interruptible() and
  * wait_event_interruptible_timeout(), originally defined in <linux/wait.h>
  */

@@ -174,6 +183,7 @@ static inline void freezer_do_not_count(
 static inline void freezer_count(void) {}
 static inline int freezer_should_skip(struct task_struct *p) { return 0; }
 static inline void set_freezable(void) {}
+static inline void set_freezable_with_signal(void) {}
 
 #define wait_event_freezable(wq, condition)				\
 		wait_event_interruptible(wq, condition)

Index: linux-2.6/include/linux/sched.h
===================================================================
@@ -1499,6 +1499,7 @@ static inline void put_task_struct(struc
 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
+#define PF_FREEZER_NOSIG 0x80000000	/* Freezer won't send signals to it */
 
 /*
  * Only the _current_ task can read/write to tsk->flags, but other

Index: linux-2.6/kernel/kthread.c
===================================================================
@@ -234,7 +234,7 @@ int kthreadd(void *unused)
 	set_user_nice(tsk, KTHREAD_NICE_LEVEL);
 	set_cpus_allowed(tsk, CPU_MASK_ALL);
 
-	current->flags |= PF_NOFREEZE;
+	current->flags |= PF_NOFREEZE | PF_FREEZER_NOSIG;
 
 	for (;;) {
 		set_current_state(TASK_INTERRUPTIBLE);

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---
 include/linux/cgroup_signal.h |   28 +++++++++
 include/linux/cgroup_subsys.h |    6 +
 init/Kconfig                  |    6 +
 kernel/Makefile               |    1 
 kernel/cgroup_signal.c        |  129 ++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 170 insertions(+)
Index: linux-2.6.25-mm1/include/linux/cgroup_signal.h
===================================================================
@@ -0,0 +1,28 @@
+#ifndef _LINUX_CGROUP_SIGNAL_H
+#define _LINUX_CGROUP_SIGNAL_H
+/*
+ * cgroup_signal.h -  control group freezer subsystem interface
+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Author : Cedric Le Goater <clg-NmTC/[email protected]>
+ * Author : Matt Helsley <matthltc-r/[email protected]>
+ */
+
+#include <linux/cgroup.h>
+
+#ifdef CONFIG_CGROUP_SIGNAL
+
+struct stateless {
+	struct cgroup_subsys_state css;
+};
+
+static inline struct stateless *cgroup_signal(struct cgroup *cgroup)
+{
+	return container_of(cgroup_subsys_state(cgroup, signal_subsys_id),
+			    struct stateless, css);
+}
+
+#else /* !CONFIG_CGROUP_SIGNAL */
+#endif /* !CONFIG_CGROUP_SIGNAL */
+#endif /* _LINUX_CGROUP_SIGNAL_H */

Index: linux-2.6.25-mm1/init/Kconfig
===================================================================
@@ -328,10 +328,16 @@ config CGROUP_FREEZER
         depends on CGROUPS
         help
           Provides a way to freeze and unfreeze all tasks in a
 	  cgroup
 
+config CGROUP_SIGNAL
+        bool "control group signal subsystem"
+        depends on CGROUPS
+        help
+          Provides a way to signal all tasks in a cgroup
+
 config FAIR_GROUP_SCHED
 	bool "Group scheduling for SCHED_OTHER"
 	depends on GROUP_SCHED
 	default y
 

Index: linux-2.6.25-mm1/kernel/Makefile
===================================================================
@@ -47,10 +47,11 @@ obj-$(CONFIG_KEXEC) += kexec.o
 obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
 obj-$(CONFIG_COMPAT) += compat.o
 obj-$(CONFIG_CGROUPS) += cgroup.o
 obj-$(CONFIG_CGROUP_DEBUG) += cgroup_debug.o
 obj-$(CONFIG_CGROUP_FREEZER) += cgroup_freezer.o
+obj-$(CONFIG_CGROUP_SIGNAL) += cgroup_signal.o
 obj-$(CONFIG_CPUSETS) += cpuset.o
 obj-$(CONFIG_CGROUP_NS) += ns_cgroup.o
 obj-$(CONFIG_UTS_NS) += utsname.o
 obj-$(CONFIG_USER_NS) += user_namespace.o
 obj-$(CONFIG_PID_NS) += pid_namespace.o

Index: linux-2.6.25-mm1/include/linux/cgroup_subsys.h
===================================================================
@@ -52,5 +52,11 @@ SUBSYS(devices)
 #ifdef CONFIG_CGROUP_FREEZER
 SUBSYS(freezer)
 #endif
 
 /* */
+
+#ifdef CONFIG_CGROUP_SIGNAL
+SUBSYS(signal)
+#endif
+
+/* */

 include/linux/cgroup_freezer.h |   65 +++++++++
 include/linux/cgroup_subsys.h  |    6 
 init/Kconfig                   |    7 +
 kernel/Makefile                |    1 
 kernel/cgroup_freezer.c        |  276 +++++++++++++++++++++++++++++++++++++++++
 kernel/freezer.c               |    1 
 6 files changed, 356 insertions(+)
Index: linux-2.6.25-mm1/include/linux/cgroup_freezer.h
===================================================================
@@ -0,0 +1,65 @@
+#ifndef _LINUX_CGROUP_FREEZER_H
+#define _LINUX_CGROUP_FREEZER_H
+/*
+ * cgroup_freezer.h -  control group freezer subsystem interface
+ *
+ * Copyright IBM Corporation, 2007
+ *
+ * Author : Cedric Le Goater <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#include <linux/cgroup.h>
+
+#ifdef CONFIG_CGROUP_FREEZER
+
+enum freezer_state {
+	STATE_RUNNING = 0,
+	STATE_FREEZING,
+	STATE_FROZEN,
+};
+
+struct freezer {
+	struct cgroup_subsys_state css;
+	enum freezer_state state;
+	spinlock_t lock;
+};
+
+static inline struct freezer *cgroup_freezer(
+		struct cgroup *cgroup)
+{
+	return container_of(
+		cgroup_subsys_state(cgroup, freezer_subsys_id),
+		struct freezer, css);
+}
+
+static inline int cgroup_frozen(struct task_struct *task)
+{
+	struct cgroup *cgroup = task_cgroup(task, freezer_subsys_id);
+	struct freezer *freezer = cgroup_freezer(cgroup);
+	enum freezer_state state;
+
+	spin_lock(&freezer->lock);
+	state = freezer->state;
+	spin_unlock(&freezer->lock);
+
+	return (state == STATE_FROZEN);
+}
+
+#else /* !CONFIG_CGROUP_FREEZER */
+
+static inline int cgroup_frozen(struct task_struct *task)
+{
+	return 0;
+}
+
+#endif /* !CONFIG_CGROUP_FREEZER */
+
+#endif /* _LINUX_CGROUP_FREEZER_H */

Index: linux-2.6.25-mm1/include/linux/cgroup_subsys.h
===================================================================
@@ -46,5 +46,11 @@ SUBSYS(mem_cgroup)
 #ifdef CONFIG_CGROUP_DEVICE
 SUBSYS(devices)
 #endif
 
 /* */
+
+#ifdef CONFIG_CGROUP_FREEZER
+SUBSYS(freezer)
+#endif
+
+/* */

Index: linux-2.6.25-mm1/init/Kconfig
===================================================================
@@ -321,10 +321,17 @@ config GROUP_SCHED
 	default y
 	help
 	  This feature lets CPU scheduler recognize task groups and control CPU
 	  bandwidth allocation to such task groups.
 
+config CGROUP_FREEZER
+        bool "control group freezer subsystem"
+        depends on CGROUPS
+        help
+          Provides a way to freeze and unfreeze all tasks in a
+	  cgroup
+
 config FAIR_GROUP_SCHED
 	bool "Group scheduling for SCHED_OTHER"
 	depends on GROUP_SCHED
 	default y
 

Index: linux-2.6.25-mm1/kernel/Makefile
===================================================================
@@ -46,10 +46,11 @@ obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
 obj-$(CONFIG_KEXEC) += kexec.o
 obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
 obj-$(CONFIG_COMPAT) += compat.o
 obj-$(CONFIG_CGROUPS) += cgroup.o
 obj-$(CONFIG_CGROUP_DEBUG) += cgroup_debug.o
+obj-$(CONFIG_CGROUP_FREEZER) += cgroup_freezer.o
 obj-$(CONFIG_CPUSETS) += cpuset.o
 obj-$(CONFIG_CGROUP_NS) += ns_cgroup.o
 obj-$(CONFIG_UTS_NS) += utsname.o
 obj-$(CONFIG_USER_NS) += user_namespace.o
 obj-$(CONFIG_PID_NS) += pid_namespace.o

Index: linux-2.6.25-mm1/kernel/freezer.c
===================================================================
@@ -120,5 +120,6 @@ int freeze_task(struct task_struct *p, i
 		}
 	}
 	task_unlock(p);
 	return ret;
 }
+EXPORT_SYMBOL(freeze_task);

 include/linux/cgroup_freezer.h |   65 +++++++++
 include/linux/cgroup_subsys.h  |    6 
 init/Kconfig                   |    7 +
 kernel/Makefile                |    1 
 kernel/cgroup_freezer.c        |  276 +++++++++++++++++++++++++++++++++++++++++
 kernel/freezer.c               |    1 
 6 files changed, 356 insertions(+)
Index: linux-2.6.25-mm1/include/linux/cgroup_freezer.h
===================================================================
@@ -0,0 +1,65 @@
+#ifndef _LINUX_CGROUP_FREEZER_H
+#define _LINUX_CGROUP_FREEZER_H
+/*
+ * cgroup_freezer.h -  control group freezer subsystem interface
+ *
+ * Copyright IBM Corporation, 2007
+ *
+ * Author : Cedric Le Goater <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#include <linux/cgroup.h>
+
+#ifdef CONFIG_CGROUP_FREEZER
+
+enum freezer_state {
+	STATE_RUNNING = 0,
+	STATE_FREEZING,
+	STATE_FROZEN,
+};
+
+struct freezer {
+	struct cgroup_subsys_state css;
+	enum freezer_state state;
+	spinlock_t lock;
+};
+
+static inline struct freezer *cgroup_freezer(
+		struct cgroup *cgroup)
+{
+	return container_of(
+		cgroup_subsys_state(cgroup, freezer_subsys_id),
+		struct freezer, css);
+}
+
+static inline int cgroup_frozen(struct task_struct *task)
+{
+	struct cgroup *cgroup = task_cgroup(task, freezer_subsys_id);
+	struct freezer *freezer = cgroup_freezer(cgroup);
+	enum freezer_state state;
+
+	spin_lock(&freezer->lock);
+	state = freezer->state;
+	spin_unlock(&freezer->lock);
+
+	return (state == STATE_FROZEN);
+}
+
+#else /* !CONFIG_CGROUP_FREEZER */
+
+static inline int cgroup_frozen(struct task_struct *task)
+{
+	return 0;
+}
+
+#endif /* !CONFIG_CGROUP_FREEZER */
+
+#endif /* _LINUX_CGROUP_FREEZER_H */

Index: linux-2.6.25-mm1/include/linux/cgroup_subsys.h
===================================================================
@@ -46,5 +46,11 @@ SUBSYS(mem_cgroup)
 #ifdef CONFIG_CGROUP_DEVICE
 SUBSYS(devices)
 #endif
 
 /* */
+
+#ifdef CONFIG_CGROUP_FREEZER
+SUBSYS(freezer)
+#endif
+
+/* */

Index: linux-2.6.25-mm1/init/Kconfig
===================================================================
@@ -321,10 +321,17 @@ config GROUP_SCHED
 	default y
 	help
 	  This feature lets CPU scheduler recognize task groups and control CPU
 	  bandwidth allocation to such task groups.
 
+config CGROUP_FREEZER
+        bool "control group freezer subsystem"
+        depends on CGROUPS
+        help
+          Provides a way to freeze and unfreeze all tasks in a
+	  cgroup
+
 config FAIR_GROUP_SCHED
 	bool "Group scheduling for SCHED_OTHER"
 	depends on GROUP_SCHED
 	default y
 

Index: linux-2.6.25-mm1/kernel/Makefile
===================================================================
@@ -46,10 +46,11 @@ obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
 obj-$(CONFIG_KEXEC) += kexec.o
 obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
 obj-$(CONFIG_COMPAT) += compat.o
 obj-$(CONFIG_CGROUPS) += cgroup.o
 obj-$(CONFIG_CGROUP_DEBUG) += cgroup_debug.o
+obj-$(CONFIG_CGROUP_FREEZER) += cgroup_freezer.o
 obj-$(CONFIG_CPUSETS) += cpuset.o
 obj-$(CONFIG_CGROUP_NS) += ns_cgroup.o
 obj-$(CONFIG_UTS_NS) += utsname.o
 obj-$(CONFIG_USER_NS) += user_namespace.o
 obj-$(CONFIG_PID_NS) += pid_namespace.o

Index: linux-2.6.25-mm1/kernel/freezer.c
===================================================================
@@ -120,5 +120,6 @@ int freeze_task(struct task_struct *p, i
 		}
 	}
 	task_unlock(p);
 	return ret;
 }
+EXPORT_SYMBOL(freeze_task);

+static const char *freezer_state_strs[] = {
+	"RUNNING\n",
+	"FREEZING\n" ,
+	"FROZEN\n"
+};

+static inline int cgroup_frozen(struct task_struct *task)
+{
+	struct cgroup *cgroup = task_cgroup(task, freezer_subsys_id);
+	struct freezer *freezer = cgroup_freezer(cgroup);
+	enum freezer_state state;
+
+	spin_lock(&freezer->lock);
+	state = freezer->state;
+	spin_unlock(&freezer->lock);
+
+	return (state == STATE_FROZEN);
+}

+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+

+static int freezer_can_attach(struct cgroup_subsys *ss,
+			      struct cgroup *new_cgroup,
+			      struct task_struct *task)
+{
+	struct freezer *freezer = cgroup_freezer(new_cgroup);
+	int retval = 0;
+
+	if (freezer->state == STATE_FROZEN)
+		retval = -EBUSY;
+
+	return retval;
+}

+static ssize_t freezer_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;

+	int retval = 0;
+	enum freezer_state goal_state;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+
+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;

+	if (strcmp(buffer, "RUNNING") == 0)
+		goal_state = STATE_RUNNING;
+	else if (strcmp(buffer, "FROZEN") == 0)
+		goal_state = STATE_FROZEN;

+static ssize_t freezer_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;
+	int retval = 0;
+	enum freezer_state goal_state;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+
+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;
+
+	if (copy_from_user(buffer, userbuf, nbytes)) {
+		retval = -EFAULT;
+		goto free_buffer;
+	}
+	buffer[nbytes] = 0;	/* nul-terminate */
+	strstrip(buffer);
+	if (strcmp(buffer, "RUNNING") == 0)
+		goal_state = STATE_RUNNING;
+	else if (strcmp(buffer, "FROZEN") == 0)
+		goal_state = STATE_FROZEN;
+	else {

+		retval = -EIO;
+		goto free_buffer;
+	}
+
+	cgroup_lock();
+
+	if (cgroup_is_removed(cgroup)) {
+		retval = -ENODEV;
+		goto unlock;
+	}

+	retval = freezer_freeze(cgroup, goal_state);
+	if (retval == 0)
+		retval = nbytes;
+unlock:
+	cgroup_unlock();
+free_buffer:
+	kfree(buffer);
+	return retval;
+}

+static const char *freezer_state_strs[] = {
+	"RUNNING\n",
+	"FREEZING\n" ,
+	"FROZEN\n"
+};

+static inline int cgroup_frozen(struct task_struct *task)
+{
+	struct cgroup *cgroup = task_cgroup(task, freezer_subsys_id);
+	struct freezer *freezer = cgroup_freezer(cgroup);
+	enum freezer_state state;
+
+	spin_lock(&freezer->lock);
+	state = freezer->state;
+	spin_unlock(&freezer->lock);
+
+	return (state == STATE_FROZEN);
+}

+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+

+static int freezer_can_attach(struct cgroup_subsys *ss,
+			      struct cgroup *new_cgroup,
+			      struct task_struct *task)
+{
+	struct freezer *freezer = cgroup_freezer(new_cgroup);
+	int retval = 0;
+
+	if (freezer->state == STATE_FROZEN)
+		retval = -EBUSY;
+
+	return retval;
+}

+static ssize_t freezer_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;

+	int retval = 0;
+	enum freezer_state goal_state;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+
+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;

+	if (strcmp(buffer, "RUNNING") == 0)
+		goal_state = STATE_RUNNING;
+	else if (strcmp(buffer, "FROZEN") == 0)
+		goal_state = STATE_FROZEN;

+static const char *freezer_state_strs[] = {
+	"RUNNING\n",
+	"FREEZING\n" ,
+	"FROZEN\n"
+};

+static inline int cgroup_frozen(struct task_struct *task)
+{
+	struct cgroup *cgroup = task_cgroup(task, freezer_subsys_id);
+	struct freezer *freezer = cgroup_freezer(cgroup);
+	enum freezer_state state;
+
+	spin_lock(&freezer->lock);
+	state = freezer->state;
+	spin_unlock(&freezer->lock);
+
+	return (state == STATE_FROZEN);
+}

+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+

+static int freezer_can_attach(struct cgroup_subsys *ss,
+			      struct cgroup *new_cgroup,
+			      struct task_struct *task)
+{
+	struct freezer *freezer = cgroup_freezer(new_cgroup);
+	int retval = 0;
+
+	if (freezer->state == STATE_FROZEN)
+		retval = -EBUSY;
+
+	return retval;
+}

+static ssize_t freezer_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;

+	int retval = 0;
+	enum freezer_state goal_state;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+
+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;

+	if (strcmp(buffer, "RUNNING") == 0)
+		goal_state = STATE_RUNNING;
+	else if (strcmp(buffer, "FROZEN") == 0)
+		goal_state = STATE_FROZEN;

+static const char *freezer_state_strs[] = {
+	"RUNNING\n",
+	"FREEZING\n" ,
+	"FROZEN\n"
+};

+static inline int cgroup_frozen(struct task_struct *task)
+{
+	struct cgroup *cgroup = task_cgroup(task, freezer_subsys_id);
+	struct freezer *freezer = cgroup_freezer(cgroup);
+	enum freezer_state state;
+
+	spin_lock(&freezer->lock);
+	state = freezer->state;
+	spin_unlock(&freezer->lock);
+
+	return (state == STATE_FROZEN);
+}

+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+

+static int freezer_can_attach(struct cgroup_subsys *ss,
+			      struct cgroup *new_cgroup,
+			      struct task_struct *task)
+{
+	struct freezer *freezer = cgroup_freezer(new_cgroup);
+	int retval = 0;
+
+	if (freezer->state == STATE_FROZEN)
+		retval = -EBUSY;
+
+	return retval;
+}

+static ssize_t freezer_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;

+	int retval = 0;
+	enum freezer_state goal_state;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+
+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;

+	if (strcmp(buffer, "RUNNING") == 0)
+		goal_state = STATE_RUNNING;
+	else if (strcmp(buffer, "FROZEN") == 0)
+		goal_state = STATE_FROZEN;

+static const char *freezer_state_strs[] = {
+	"RUNNING\n",
+	"FREEZING\n" ,
+	"FROZEN\n"
+};

+static inline int cgroup_frozen(struct task_struct *task)
+{
+	struct cgroup *cgroup = task_cgroup(task, freezer_subsys_id);
+	struct freezer *freezer = cgroup_freezer(cgroup);
+	enum freezer_state state;
+
+	spin_lock(&freezer->lock);

+	state = freezer->state;
+	spin_unlock(&freezer->lock);
+
+	return (state == STATE_FROZEN);
+}

+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+

+static int freezer_can_attach(struct cgroup_subsys *ss,
+			      struct cgroup *new_cgroup,
+			      struct task_struct *task)
+{
+	struct freezer *freezer = cgroup_freezer(new_cgroup);
+	int retval = 0;
+
+	if (freezer->state == STATE_FROZEN)
+		retval = -EBUSY;

+
+	return retval;
+}

+static ssize_t freezer_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;
+	int retval = 0;
+	enum freezer_state goal_state;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+

+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;

+	if (strcmp(buffer, "RUNNING") == 0)
+		goal_state = STATE_RUNNING;
+	else if (strcmp(buffer, "FROZEN") == 0)
+		goal_state = STATE_FROZEN;

+static const char *freezer_state_strs[] = {
+	"RUNNING\n",
+	"FREEZING\n" ,
+	"FROZEN\n"
+};

+static inline int cgroup_frozen(struct task_struct *task)
+{
+	struct cgroup *cgroup = task_cgroup(task, freezer_subsys_id);
+	struct freezer *freezer = cgroup_freezer(cgroup);
+	enum freezer_state state;
+
+	spin_lock(&freezer->lock);
+	state = freezer->state;
+	spin_unlock(&freezer->lock);
+
+	return (state == STATE_FROZEN);
+}

+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+

+static int freezer_can_attach(struct cgroup_subsys *ss,
+			      struct cgroup *new_cgroup,
+			      struct task_struct *task)
+{
+	struct freezer *freezer = cgroup_freezer(new_cgroup);
+	int retval = 0;
+
+	if (freezer->state == STATE_FROZEN)
+		retval = -EBUSY;
+
+	return retval;
+}

+static ssize_t freezer_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;

+	int retval = 0;
+	enum freezer_state goal_state;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+
+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;

+	if (strcmp(buffer, "RUNNING") == 0)
+		goal_state = STATE_RUNNING;
+	else if (strcmp(buffer, "FROZEN") == 0)
+		goal_state = STATE_FROZEN;

+static const char *freezer_state_strs[] = {
+	"RUNNING\n",
+	"FREEZING\n" ,
+	"FROZEN\n"
+};

+static inline int cgroup_frozen(struct task_struct *task)
+{
+	struct cgroup *cgroup = task_cgroup(task, freezer_subsys_id);
+	struct freezer *freezer = cgroup_freezer(cgroup);
+	enum freezer_state state;
+
+	spin_lock(&freezer->lock);
+	state = freezer->state;
+	spin_unlock(&freezer->lock);
+
+	return (state == STATE_FROZEN);
+}

+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+

+static int freezer_can_attach(struct cgroup_subsys *ss,
+			      struct cgroup *new_cgroup,
+			      struct task_struct *task)
+{
+	struct freezer *freezer = cgroup_freezer(new_cgroup);
+	int retval = 0;
+
+	if (freezer->state == STATE_FROZEN)
+		retval = -EBUSY;
+
+	return retval;
+}

+static ssize_t freezer_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;

+	int retval = 0;
+	enum freezer_state goal_state;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+
+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;

+	if (strcmp(buffer, "RUNNING") == 0)
+		goal_state = STATE_RUNNING;
+	else if (strcmp(buffer, "FROZEN") == 0)
+		goal_state = STATE_FROZEN;

+static const char *freezer_state_strs[] = {
+	"RUNNING\n",
+	"FREEZING\n" ,
+	"FROZEN\n"
+};

+static inline int cgroup_frozen(struct task_struct *task)
+{
+	struct cgroup *cgroup = task_cgroup(task, freezer_subsys_id);
+	struct freezer *freezer = cgroup_freezer(cgroup);
+	enum freezer_state state;
+
+	spin_lock(&freezer->lock);

+	state = freezer->state;
+	spin_unlock(&freezer->lock);
+
+	return (state == STATE_FROZEN);
+}

+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+

+static int freezer_can_attach(struct cgroup_subsys *ss,
+			      struct cgroup *new_cgroup,
+			      struct task_struct *task)
+{
+	struct freezer *freezer = cgroup_freezer(new_cgroup);
+	int retval = 0;
+
+	if (freezer->state == STATE_FROZEN)
+		retval = -EBUSY;

+
+	return retval;
+}

+static ssize_t freezer_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;
+	int retval = 0;
+	enum freezer_state goal_state;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+

+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;

+	if (strcmp(buffer, "RUNNING") == 0)
+		goal_state = STATE_RUNNING;
+	else if (strcmp(buffer, "FROZEN") == 0)
+		goal_state = STATE_FROZEN;

+static const char *freezer_state_strs[] = {
+	"RUNNING\n",
+	"FREEZING\n" ,
+	"FROZEN\n"
+};

+static inline int cgroup_frozen(struct task_struct *task)
+{
+	struct cgroup *cgroup = task_cgroup(task, freezer_subsys_id);
+	struct freezer *freezer = cgroup_freezer(cgroup);
+	enum freezer_state state;
+
+	spin_lock(&freezer->lock);

+	state = freezer->state;
+	spin_unlock(&freezer->lock);
+
+	return (state == STATE_FROZEN);
+}

+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+

+static int freezer_can_attach(struct cgroup_subsys *ss,
+			      struct cgroup *new_cgroup,
+			      struct task_struct *task)
+{
+	struct freezer *freezer = cgroup_freezer(new_cgroup);
+	int retval = 0;
+
+	if (freezer->state == STATE_FROZEN)
+		retval = -EBUSY;

+
+	return retval;
+}

+static ssize_t freezer_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;
+	int retval = 0;
+	enum freezer_state goal_state;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+

+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;

+	if (strcmp(buffer, "RUNNING") == 0)
+		goal_state = STATE_RUNNING;
+	else if (strcmp(buffer, "FROZEN") == 0)
+		goal_state = STATE_FROZEN;

+static ssize_t freezer_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;
+	int retval = 0;
+	enum freezer_state goal_state;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+
+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;
+
+	if (copy_from_user(buffer, userbuf, nbytes)) {
+		retval = -EFAULT;
+		goto free_buffer;
+	}
+	buffer[nbytes] = 0;	/* nul-terminate */
+	strstrip(buffer);
+	if (strcmp(buffer, "RUNNING") == 0)
+		goal_state = STATE_RUNNING;
+	else if (strcmp(buffer, "FROZEN") == 0)
+		goal_state = STATE_FROZEN;
+	else {

+		retval = -EIO;
+		goto free_buffer;
+	}
+
+	cgroup_lock();
+
+	if (cgroup_is_removed(cgroup)) {
+		retval = -ENODEV;
+		goto unlock;
+	}

+	retval = freezer_freeze(cgroup, goal_state);
+	if (retval == 0)
+		retval = nbytes;
+unlock:
+	cgroup_unlock();
+free_buffer:
+	kfree(buffer);
+	return retval;
+}

+static ssize_t freezer_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;
+	int retval = 0;
+	enum freezer_state goal_state;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+
+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;
+
+	if (copy_from_user(buffer, userbuf, nbytes)) {
+		retval = -EFAULT;
+		goto free_buffer;
+	}
+	buffer[nbytes] = 0;	/* nul-terminate */
+	strstrip(buffer);
+	if (strcmp(buffer, "RUNNING") == 0)
+		goal_state = STATE_RUNNING;
+	else if (strcmp(buffer, "FROZEN") == 0)
+		goal_state = STATE_FROZEN;
+	else {

+		retval = -EIO;
+		goto free_buffer;
+	}
+
+	cgroup_lock();
+
+	if (cgroup_is_removed(cgroup)) {
+		retval = -ENODEV;
+		goto unlock;
+	}

+	retval = freezer_freeze(cgroup, goal_state);
+	if (retval == 0)
+		retval = nbytes;
+unlock:
+	cgroup_unlock();
+free_buffer:
+	kfree(buffer);
+	return retval;
+}

+	cgroup_lock();
+
+	if (cgroup_is_removed(cgroup)) {
+		retval = -ENODEV;
+		goto unlock;
+	}

+	cgroup_lock();
+
+	if (cgroup_is_removed(cgroup)) {
+		retval = -ENODEV;
+		goto unlock;
+	}

+	cgroup_lock();
+
+	if (cgroup_is_removed(cgroup)) {
+		retval = -ENODEV;
+		goto unlock;
+	}

---
 kernel/power/process.c |    4 ++++
 1 file changed, 4 insertions(+)
Index: linux-2.6.25-mm1/kernel/power/process.c
===================================================================
@@ -11,10 +11,11 @@
 #include <linux/interrupt.h>
 #include <linux/suspend.h>
 #include <linux/module.h>
 #include <linux/syscalls.h>
 #include <linux/freezer.h>
+#include <linux/cgroup_freezer.h>
 
 /* 
  * Timeout for stopping processes
  */
 #define TIMEOUT	(20 * HZ)

@@ -150,10 +151,13 @@ static void thaw_tasks(int thaw_user_spa
 			continue;
 
 		if (!p->mm == thaw_user_space)
 			continue;
 
+		if (cgroup_frozen(p))
+			continue;
+
 		thaw_process(p);
 	} while_each_thread(g, p);
 	read_unlock(&tasklist_lock);
 }
 

---
 kernel/power/process.c |    4 ++++
 1 file changed, 4 insertions(+)
Index: linux-2.6.25-mm1/kernel/power/process.c
===================================================================
@@ -11,10 +11,11 @@
 #include <linux/interrupt.h>
 #include <linux/suspend.h>
 #include <linux/module.h>
 #include <linux/syscalls.h>
 #include <linux/freezer.h>
+#include <linux/cgroup_freezer.h>
 
 /* 
  * Timeout for stopping processes
  */
 #define TIMEOUT	(20 * HZ)

@@ -150,10 +151,13 @@ static void thaw_tasks(int thaw_user_spa
 			continue;
 
 		if (!p->mm == thaw_user_space)
 			continue;
 
+		if (cgroup_frozen(p))
+			continue;
+
 		thaw_process(p);
 	} while_each_thread(g, p);
 	read_unlock(&tasklist_lock);
 }
 

---
 include/linux/cgroup_signal.h |   28 +++++++++
 include/linux/cgroup_subsys.h |    6 +
 init/Kconfig                  |    6 +
 kernel/Makefile               |    1 
 kernel/cgroup_signal.c        |  129 ++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 170 insertions(+)
Index: linux-2.6.25-mm1/include/linux/cgroup_signal.h
===================================================================
@@ -0,0 +1,28 @@
+#ifndef _LINUX_CGROUP_SIGNAL_H
+#define _LINUX_CGROUP_SIGNAL_H
+/*
+ * cgroup_signal.h -  control group freezer subsystem interface
+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Author : Cedric Le Goater <[email protected]>
+ * Author : Matt Helsley <[email protected]>
+ */
+
+#include <linux/cgroup.h>
+
+#ifdef CONFIG_CGROUP_SIGNAL
+
+struct stateless {
+	struct cgroup_subsys_state css;
+};
+
+static inline struct stateless *cgroup_signal(struct cgroup *cgroup)
+{
+	return container_of(cgroup_subsys_state(cgroup, signal_subsys_id),
+			    struct stateless, css);
+}
+
+#else /* !CONFIG_CGROUP_SIGNAL */
+#endif /* !CONFIG_CGROUP_SIGNAL */
+#endif /* _LINUX_CGROUP_SIGNAL_H */

Index: linux-2.6.25-mm1/init/Kconfig
===================================================================
@@ -328,10 +328,16 @@ config CGROUP_FREEZER
         depends on CGROUPS
         help
           Provides a way to freeze and unfreeze all tasks in a
 	  cgroup
 
+config CGROUP_SIGNAL
+        bool "control group signal subsystem"
+        depends on CGROUPS
+        help
+          Provides a way to signal all tasks in a cgroup
+
 config FAIR_GROUP_SCHED
 	bool "Group scheduling for SCHED_OTHER"
 	depends on GROUP_SCHED
 	default y
 

Index: linux-2.6.25-mm1/kernel/Makefile
===================================================================
@@ -47,10 +47,11 @@ obj-$(CONFIG_KEXEC) += kexec.o
 obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
 obj-$(CONFIG_COMPAT) += compat.o
 obj-$(CONFIG_CGROUPS) += cgroup.o
 obj-$(CONFIG_CGROUP_DEBUG) += cgroup_debug.o
 obj-$(CONFIG_CGROUP_FREEZER) += cgroup_freezer.o
+obj-$(CONFIG_CGROUP_SIGNAL) += cgroup_signal.o
 obj-$(CONFIG_CPUSETS) += cpuset.o
 obj-$(CONFIG_CGROUP_NS) += ns_cgroup.o
 obj-$(CONFIG_UTS_NS) += utsname.o
 obj-$(CONFIG_USER_NS) += user_namespace.o
 obj-$(CONFIG_PID_NS) += pid_namespace.o

Index: linux-2.6.25-mm1/include/linux/cgroup_subsys.h
===================================================================
@@ -52,5 +52,11 @@ SUBSYS(devices)
 #ifdef CONFIG_CGROUP_FREEZER
 SUBSYS(freezer)
 #endif
 
 /* */
+
+#ifdef CONFIG_CGROUP_SIGNAL
+SUBSYS(signal)
+#endif
+
+/* */

---
 include/linux/cgroup_signal.h |   28 +++++++++
 include/linux/cgroup_subsys.h |    6 +
 init/Kconfig                  |    6 +
 kernel/Makefile               |    1 
 kernel/cgroup_signal.c        |  129 ++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 170 insertions(+)
Index: linux-2.6.25-mm1/include/linux/cgroup_signal.h
===================================================================
@@ -0,0 +1,28 @@
+#ifndef _LINUX_CGROUP_SIGNAL_H
+#define _LINUX_CGROUP_SIGNAL_H
+/*
+ * cgroup_signal.h -  control group freezer subsystem interface
+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Author : Cedric Le Goater <[email protected]>
+ * Author : Matt Helsley <[email protected]>
+ */
+
+#include <linux/cgroup.h>
+
+#ifdef CONFIG_CGROUP_SIGNAL
+
+struct stateless {
+	struct cgroup_subsys_state css;
+};
+
+static inline struct stateless *cgroup_signal(struct cgroup *cgroup)
+{
+	return container_of(cgroup_subsys_state(cgroup, signal_subsys_id),
+			    struct stateless, css);
+}
+
+#else /* !CONFIG_CGROUP_SIGNAL */
+#endif /* !CONFIG_CGROUP_SIGNAL */
+#endif /* _LINUX_CGROUP_SIGNAL_H */

Index: linux-2.6.25-mm1/init/Kconfig
===================================================================
@@ -328,10 +328,16 @@ config CGROUP_FREEZER
         depends on CGROUPS
         help
           Provides a way to freeze and unfreeze all tasks in a
 	  cgroup
 
+config CGROUP_SIGNAL
+        bool "control group signal subsystem"
+        depends on CGROUPS
+        help
+          Provides a way to signal all tasks in a cgroup
+
 config FAIR_GROUP_SCHED
 	bool "Group scheduling for SCHED_OTHER"
 	depends on GROUP_SCHED
 	default y
 

Index: linux-2.6.25-mm1/kernel/Makefile
===================================================================
@@ -47,10 +47,11 @@ obj-$(CONFIG_KEXEC) += kexec.o
 obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
 obj-$(CONFIG_COMPAT) += compat.o
 obj-$(CONFIG_CGROUPS) += cgroup.o
 obj-$(CONFIG_CGROUP_DEBUG) += cgroup_debug.o
 obj-$(CONFIG_CGROUP_FREEZER) += cgroup_freezer.o
+obj-$(CONFIG_CGROUP_SIGNAL) += cgroup_signal.o
 obj-$(CONFIG_CPUSETS) += cpuset.o
 obj-$(CONFIG_CGROUP_NS) += ns_cgroup.o
 obj-$(CONFIG_UTS_NS) += utsname.o
 obj-$(CONFIG_USER_NS) += user_namespace.o
 obj-$(CONFIG_PID_NS) += pid_namespace.o

Index: linux-2.6.25-mm1/include/linux/cgroup_subsys.h
===================================================================
@@ -52,5 +52,11 @@ SUBSYS(devices)
 #ifdef CONFIG_CGROUP_FREEZER
 SUBSYS(freezer)
 #endif
 
 /* */
+
+#ifdef CONFIG_CGROUP_SIGNAL
+SUBSYS(signal)
+#endif
+
+/* */

+static struct cftype kill_file = {
+	.name = "kill",

                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <pj-sJ/[email protected]> 1.940.382.4214
---
 include/linux/cgroup_signal.h |   28 +++++++++
 include/linux/cgroup_subsys.h |    6 +
 init/Kconfig                  |    6 +
 kernel/Makefile               |    1 
 kernel/cgroup_signal.c        |  129 ++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 170 insertions(+)
@@ -0,0 +1,28 @@
+#ifndef _LINUX_CGROUP_SIGNAL_H
+#define _LINUX_CGROUP_SIGNAL_H
+/*
+ * cgroup_signal.h -  control group freezer subsystem interface

+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Author : Cedric Le Goater <clg-NmTC/[email protected]>

+ * Author : Matt Helsley <matthltc-r/[email protected]>
+ */
+
+#include <linux/cgroup.h>
+
+#ifdef CONFIG_CGROUP_SIGNAL
+
+struct stateless {
+	struct cgroup_subsys_state css;
+};

+static inline struct stateless *cgroup_signal(struct cgroup *cgroup)
+{
+	return container_of(cgroup_subsys_state(cgroup, signal_subsys_id),
+			    struct stateless, css);
+}
+
+#else /* !CONFIG_CGROUP_SIGNAL */
+#endif /* !CONFIG_CGROUP_SIGNAL */
+#endif /* _LINUX_CGROUP_SIGNAL_H */

@@ -0,0 +1,129 @@
+/*
+ * cgroup_signal.c -  control group signal subsystem
+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Author : Cedric Le Goater <clg-NmTC/[email protected]>
+ * Author : Matt Helsley <matthltc-r/[email protected]>
+ */
+
+#include <linux/module.h>
+#include <linux/cgroup.h>
+#include <linux/fs.h>
+#include <linux/uaccess.h>
+#include <linux/cgroup_signal.h>
+
+struct cgroup_subsys signal_subsys;
+
+static struct cgroup_subsys_state *signal_create(
+	struct cgroup_subsys *ss, struct cgroup *cgroup)
+{
+	struct stateless *dummy;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+
+	dummy = kzalloc(sizeof(struct stateless), GFP_KERNEL);
+	if (!dummy)
+		return ERR_PTR(-ENOMEM);
+	return  &dummy->css;
+}
+
+static void signal_destroy(struct cgroup_subsys *ss,
+			   struct cgroup *cgroup)
+{
+	kfree(cgroup_signal(cgroup));
+}
+
+
+static int signal_can_attach(struct cgroup_subsys *ss,
+			     struct cgroup *new_cgroup,
+			     struct task_struct *task)
+{
+	return 0;
+}
+
+static int signal_kill(struct cgroup *cgroup, int signum)
+{
+	struct cgroup_iter it;
+	struct task_struct *task;
+	int retval = 0;
+
+	cgroup_iter_start(cgroup, &it);
+	while ((task = cgroup_iter_next(cgroup, &it))) {
+		retval = send_sig(signum, task, 1);
+		if (retval)
+			break;
+	}
+	cgroup_iter_end(cgroup, &it);
+
+	return retval;
+}
+
+static ssize_t signal_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;
+	int retval = 0;
+	int value;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+
+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;
+
+	if (copy_from_user(buffer, userbuf, nbytes)) {
+		retval = -EFAULT;
+		goto free_buffer;
+	}
+	buffer[nbytes] = 0;	/* nul-terminate */
+	if (sscanf(buffer, "%d", &value) != 1) {
+		retval = -EIO;
+		goto free_buffer;
+	}
+
+	cgroup_lock();
+
+	if (cgroup_is_removed(cgroup)) {
+		retval = -ENODEV;
+		goto unlock;
+	}
+
+	retval = signal_kill(cgroup, value);
+	if (retval == 0)
+		retval = nbytes;
+unlock:
+	cgroup_unlock();
+free_buffer:
+	kfree(buffer);
+	return retval;
+}
+
+static struct cftype kill_file = {
+	.name = "kill",
+	.write = signal_write,
+	.private = 0,
+};
+
+static int signal_populate(struct cgroup_subsys *ss, struct cgroup *cgroup)
+{
+	return cgroup_add_files(cgroup, ss, &kill_file, 1);
+}
+
+struct cgroup_subsys signal_subsys = {
+	.name		= "signal",
+	.create		= signal_create,
+	.destroy	= signal_destroy,
+	.populate	= signal_populate,
+	.subsys_id	= signal_subsys_id,
+	.can_attach	= signal_can_attach,
+	.attach		= NULL,
+	.fork		= NULL,
+	.exit		= NULL,
+};

@@ -328,10 +328,16 @@ config CGROUP_FREEZER
         depends on CGROUPS
         help
           Provides a way to freeze and unfreeze all tasks in a
 	  cgroup
 
+config CGROUP_SIGNAL
+        bool "control group signal subsystem"
+        depends on CGROUPS
+        help
+          Provides a way to signal all tasks in a cgroup
+
 config FAIR_GROUP_SCHED
 	bool "Group scheduling for SCHED_OTHER"
 	depends on GROUP_SCHED
 	default y
 

@@ -47,10 +47,11 @@ obj-$(CONFIG_KEXEC) += kexec.o
 obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
 obj-$(CONFIG_COMPAT) += compat.o
 obj-$(CONFIG_CGROUPS) += cgroup.o
 obj-$(CONFIG_CGROUP_DEBUG) += cgroup_debug.o
 obj-$(CONFIG_CGROUP_FREEZER) += cgroup_freezer.o
+obj-$(CONFIG_CGROUP_SIGNAL) += cgroup_signal.o
 obj-$(CONFIG_CPUSETS) += cpuset.o
 obj-$(CONFIG_CGROUP_NS) += ns_cgroup.o
 obj-$(CONFIG_UTS_NS) += utsname.o
 obj-$(CONFIG_USER_NS) += user_namespace.o
 obj-$(CONFIG_PID_NS) += pid_namespace.o

@@ -52,5 +52,11 @@ SUBSYS(devices)
 #ifdef CONFIG_CGROUP_FREEZER
 SUBSYS(freezer)
 #endif
 
 /* */
+
+#ifdef CONFIG_CGROUP_SIGNAL
+SUBSYS(signal)
+#endif
+
+/* */

+static struct cftype kill_file = {
+	.name = "kill",

                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <[email protected]> 1.940.382.4214
+static struct cftype kill_file = {
+	.name = "kill",

                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <[email protected]> 1.940.382.4214
+static struct cftype kill_file = {
+	.name = "kill",

+static struct cftype kill_file = {
+	.name = "kill",

+static struct cftype kill_file = {
+	.name = "kill",

                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <pj-sJ/[email protected]> 1.940.382.4214
                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <[email protected]> 1.940.382.4214
                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <[email protected]> 1.940.382.4214
+static struct cgroup_subsys_state *signal_create(
+	struct cgroup_subsys *ss, struct cgroup *cgroup)
+{
+	struct stateless *dummy;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);

+static int signal_can_attach(struct cgroup_subsys *ss,
+			     struct cgroup *new_cgroup,
+			     struct task_struct *task)
+{
+	return 0;
+}

+static int signal_kill(struct cgroup *cgroup, int signum)
+{
+	struct cgroup_iter it;
+	struct task_struct *task;
+	int retval = 0;
+

+	cgroup_iter_start(cgroup, &it);
+	while ((task = cgroup_iter_next(cgroup, &it))) {
+		retval = send_sig(signum, task, 1);
+		if (retval)
+			break;
+	}
+	cgroup_iter_end(cgroup, &it);
+
+	return retval;
+}

+static ssize_t signal_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)

+static struct cftype kill_file = {
+	.name = "kill",
+	.write = signal_write,
+	.private = 0,
+};

+static struct cgroup_subsys_state *signal_create(
+	struct cgroup_subsys *ss, struct cgroup *cgroup)
+{
+	struct stateless *dummy;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);

+	dummy = kzalloc(sizeof(struct stateless), GFP_KERNEL);
+	if (!dummy)
+		return ERR_PTR(-ENOMEM);
+	return  &dummy->css;
+}

+static int signal_can_attach(struct cgroup_subsys *ss,
+			     struct cgroup *new_cgroup,
+			     struct task_struct *task)
+{
+	return 0;
+}

+static int signal_kill(struct cgroup *cgroup, int signum)
+{
+	struct cgroup_iter it;
+	struct task_struct *task;
+	int retval = 0;
+
+	cgroup_iter_start(cgroup, &it);
+	while ((task = cgroup_iter_next(cgroup, &it))) {
+		retval = send_sig(signum, task, 1);
+		if (retval)

+			break;
+	}
+	cgroup_iter_end(cgroup, &it);
+
+	return retval;
+}

+static ssize_t signal_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)

+static struct cftype kill_file = {
+	.name = "kill",
+	.write = signal_write,
+	.private = 0,
+};

+static struct cgroup_subsys_state *signal_create(
+	struct cgroup_subsys *ss, struct cgroup *cgroup)
+{
+	struct stateless *dummy;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);

+	dummy = kzalloc(sizeof(struct stateless), GFP_KERNEL);
+	if (!dummy)
+		return ERR_PTR(-ENOMEM);
+	return  &dummy->css;
+}

+static int signal_can_attach(struct cgroup_subsys *ss,
+			     struct cgroup *new_cgroup,
+			     struct task_struct *task)
+{
+	return 0;
+}

+static int signal_kill(struct cgroup *cgroup, int signum)
+{
+	struct cgroup_iter it;
+	struct task_struct *task;
+	int retval = 0;
+
+	cgroup_iter_start(cgroup, &it);
+	while ((task = cgroup_iter_next(cgroup, &it))) {
+		retval = send_sig(signum, task, 1);
+		if (retval)

+			break;
+	}
+	cgroup_iter_end(cgroup, &it);
+
+	return retval;
+}

+static ssize_t signal_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)

+static struct cftype kill_file = {
+	.name = "kill",
+	.write = signal_write,
+	.private = 0,
+};

+static struct cgroup_subsys_state *signal_create(
+	struct cgroup_subsys *ss, struct cgroup *cgroup)
+{
+	struct stateless *dummy;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);

+	dummy = kzalloc(sizeof(struct stateless), GFP_KERNEL);
+	if (!dummy)
+		return ERR_PTR(-ENOMEM);
+	return  &dummy->css;
+}

+static int signal_can_attach(struct cgroup_subsys *ss,
+			     struct cgroup *new_cgroup,
+			     struct task_struct *task)
+{
+	return 0;
+}

+static int signal_kill(struct cgroup *cgroup, int signum)
+{
+	struct cgroup_iter it;
+	struct task_struct *task;
+	int retval = 0;
+
+	cgroup_iter_start(cgroup, &it);
+	while ((task = cgroup_iter_next(cgroup, &it))) {
+		retval = send_sig(signum, task, 1);
+		if (retval)

+			break;
+	}
+	cgroup_iter_end(cgroup, &it);
+
+	return retval;
+}

+static ssize_t signal_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)

+static struct cftype kill_file = {
+	.name = "kill",
+	.write = signal_write,
+	.private = 0,
+};

+static struct cgroup_subsys_state *signal_create(
+	struct cgroup_subsys *ss, struct cgroup *cgroup)
+{
+	struct stateless *dummy;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);

+static int signal_can_attach(struct cgroup_subsys *ss,
+			     struct cgroup *new_cgroup,
+			     struct task_struct *task)
+{
+	return 0;
+}

+static int signal_kill(struct cgroup *cgroup, int signum)
+{
+	struct cgroup_iter it;
+	struct task_struct *task;
+	int retval = 0;
+

+	cgroup_iter_start(cgroup, &it);
+	while ((task = cgroup_iter_next(cgroup, &it))) {
+		retval = send_sig(signum, task, 1);
+		if (retval)
+			break;
+	}
+	cgroup_iter_end(cgroup, &it);
+
+	return retval;
+}

+static ssize_t signal_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)

+static struct cftype kill_file = {
+	.name = "kill",
+	.write = signal_write,
+	.private = 0,
+};

---
 include/linux/cgroup_signal.h |   28 +++++++++
 include/linux/cgroup_subsys.h |    6 +
 init/Kconfig                  |    6 +
 kernel/Makefile               |    1 
 kernel/cgroup_signal.c        |  129 ++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 170 insertions(+)
@@ -0,0 +1,28 @@
+#ifndef _LINUX_CGROUP_SIGNAL_H
+#define _LINUX_CGROUP_SIGNAL_H
+/*
+ * cgroup_signal.h -  control group freezer subsystem interface

+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Author : Cedric Le Goater <[email protected]>

+ * Author : Matt Helsley <[email protected]>
+ */
+
+#include <linux/cgroup.h>
+
+#ifdef CONFIG_CGROUP_SIGNAL
+
+struct stateless {
+	struct cgroup_subsys_state css;
+};

+static inline struct stateless *cgroup_signal(struct cgroup *cgroup)
+{
+	return container_of(cgroup_subsys_state(cgroup, signal_subsys_id),
+			    struct stateless, css);
+}
+
+#else /* !CONFIG_CGROUP_SIGNAL */
+#endif /* !CONFIG_CGROUP_SIGNAL */
+#endif /* _LINUX_CGROUP_SIGNAL_H */

@@ -0,0 +1,129 @@
+/*
+ * cgroup_signal.c -  control group signal subsystem
+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Author : Cedric Le Goater <[email protected]>
+ * Author : Matt Helsley <[email protected]>
+ */
+
+#include <linux/module.h>
+#include <linux/cgroup.h>
+#include <linux/fs.h>
+#include <linux/uaccess.h>
+#include <linux/cgroup_signal.h>
+
+struct cgroup_subsys signal_subsys;
+
+static struct cgroup_subsys_state *signal_create(
+	struct cgroup_subsys *ss, struct cgroup *cgroup)
+{
+	struct stateless *dummy;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+
+	dummy = kzalloc(sizeof(struct stateless), GFP_KERNEL);
+	if (!dummy)
+		return ERR_PTR(-ENOMEM);
+	return  &dummy->css;
+}
+
+static void signal_destroy(struct cgroup_subsys *ss,
+			   struct cgroup *cgroup)
+{
+	kfree(cgroup_signal(cgroup));
+}
+
+
+static int signal_can_attach(struct cgroup_subsys *ss,
+			     struct cgroup *new_cgroup,
+			     struct task_struct *task)
+{
+	return 0;
+}
+
+static int signal_kill(struct cgroup *cgroup, int signum)
+{
+	struct cgroup_iter it;
+	struct task_struct *task;
+	int retval = 0;
+
+	cgroup_iter_start(cgroup, &it);
+	while ((task = cgroup_iter_next(cgroup, &it))) {
+		retval = send_sig(signum, task, 1);
+		if (retval)
+			break;
+	}
+	cgroup_iter_end(cgroup, &it);
+
+	return retval;
+}
+
+static ssize_t signal_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;
+	int retval = 0;
+	int value;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+
+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;
+
+	if (copy_from_user(buffer, userbuf, nbytes)) {
+		retval = -EFAULT;
+		goto free_buffer;
+	}
+	buffer[nbytes] = 0;	/* nul-terminate */
+	if (sscanf(buffer, "%d", &value) != 1) {
+		retval = -EIO;
+		goto free_buffer;
+	}
+
+	cgroup_lock();
+
+	if (cgroup_is_removed(cgroup)) {
+		retval = -ENODEV;
+		goto unlock;
+	}
+
+	retval = signal_kill(cgroup, value);
+	if (retval == 0)
+		retval = nbytes;
+unlock:
+	cgroup_unlock();
+free_buffer:
+	kfree(buffer);
+	return retval;
+}
+
+static struct cftype kill_file = {
+	.name = "kill",
+	.write = signal_write,
+	.private = 0,
+};
+
+static int signal_populate(struct cgroup_subsys *ss, struct cgroup *cgroup)
+{
+	return cgroup_add_files(cgroup, ss, &kill_file, 1);
+}
+
+struct cgroup_subsys signal_subsys = {
+	.name		= "signal",
+	.create		= signal_create,
+	.destroy	= signal_destroy,
+	.populate	= signal_populate,
+	.subsys_id	= signal_subsys_id,
+	.can_attach	= signal_can_attach,
+	.attach		= NULL,
+	.fork		= NULL,
+	.exit		= NULL,
+};

@@ -328,10 +328,16 @@ config CGROUP_FREEZER
         depends on CGROUPS
         help
           Provides a way to freeze and unfreeze all tasks in a
 	  cgroup
 
+config CGROUP_SIGNAL
+        bool "control group signal subsystem"
+        depends on CGROUPS
+        help
+          Provides a way to signal all tasks in a cgroup
+
 config FAIR_GROUP_SCHED
 	bool "Group scheduling for SCHED_OTHER"
 	depends on GROUP_SCHED
 	default y
 

@@ -47,10 +47,11 @@ obj-$(CONFIG_KEXEC) += kexec.o
 obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
 obj-$(CONFIG_COMPAT) += compat.o
 obj-$(CONFIG_CGROUPS) += cgroup.o
 obj-$(CONFIG_CGROUP_DEBUG) += cgroup_debug.o
 obj-$(CONFIG_CGROUP_FREEZER) += cgroup_freezer.o
+obj-$(CONFIG_CGROUP_SIGNAL) += cgroup_signal.o
 obj-$(CONFIG_CPUSETS) += cpuset.o
 obj-$(CONFIG_CGROUP_NS) += ns_cgroup.o
 obj-$(CONFIG_UTS_NS) += utsname.o
 obj-$(CONFIG_USER_NS) += user_namespace.o
 obj-$(CONFIG_PID_NS) += pid_namespace.o

@@ -52,5 +52,11 @@ SUBSYS(devices)
 #ifdef CONFIG_CGROUP_FREEZER
 SUBSYS(freezer)
 #endif
 
 /* */
+
+#ifdef CONFIG_CGROUP_SIGNAL
+SUBSYS(signal)
+#endif
+
+/* */

---
 include/linux/cgroup_signal.h |   28 +++++++++
 include/linux/cgroup_subsys.h |    6 +
 init/Kconfig                  |    6 +
 kernel/Makefile               |    1 
 kernel/cgroup_signal.c        |  129 ++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 170 insertions(+)
@@ -0,0 +1,28 @@
+#ifndef _LINUX_CGROUP_SIGNAL_H
+#define _LINUX_CGROUP_SIGNAL_H
+/*
+ * cgroup_signal.h -  control group freezer subsystem interface

+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Author : Cedric Le Goater <[email protected]>

+ * Author : Matt Helsley <[email protected]>
+ */
+
+#include <linux/cgroup.h>
+
+#ifdef CONFIG_CGROUP_SIGNAL
+
+struct stateless {
+	struct cgroup_subsys_state css;
+};

+static inline struct stateless *cgroup_signal(struct cgroup *cgroup)
+{
+	return container_of(cgroup_subsys_state(cgroup, signal_subsys_id),
+			    struct stateless, css);
+}
+
+#else /* !CONFIG_CGROUP_SIGNAL */
+#endif /* !CONFIG_CGROUP_SIGNAL */
+#endif /* _LINUX_CGROUP_SIGNAL_H */

@@ -0,0 +1,129 @@
+/*
+ * cgroup_signal.c -  control group signal subsystem
+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Author : Cedric Le Goater <[email protected]>
+ * Author : Matt Helsley <[email protected]>
+ */
+
+#include <linux/module.h>
+#include <linux/cgroup.h>
+#include <linux/fs.h>
+#include <linux/uaccess.h>
+#include <linux/cgroup_signal.h>
+
+struct cgroup_subsys signal_subsys;
+
+static struct cgroup_subsys_state *signal_create(
+	struct cgroup_subsys *ss, struct cgroup *cgroup)
+{
+	struct stateless *dummy;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+
+	dummy = kzalloc(sizeof(struct stateless), GFP_KERNEL);
+	if (!dummy)
+		return ERR_PTR(-ENOMEM);
+	return  &dummy->css;
+}
+
+static void signal_destroy(struct cgroup_subsys *ss,
+			   struct cgroup *cgroup)
+{
+	kfree(cgroup_signal(cgroup));
+}
+
+
+static int signal_can_attach(struct cgroup_subsys *ss,
+			     struct cgroup *new_cgroup,
+			     struct task_struct *task)
+{
+	return 0;
+}
+
+static int signal_kill(struct cgroup *cgroup, int signum)
+{
+	struct cgroup_iter it;
+	struct task_struct *task;
+	int retval = 0;
+
+	cgroup_iter_start(cgroup, &it);
+	while ((task = cgroup_iter_next(cgroup, &it))) {
+		retval = send_sig(signum, task, 1);
+		if (retval)
+			break;
+	}
+	cgroup_iter_end(cgroup, &it);
+
+	return retval;
+}
+
+static ssize_t signal_write(struct cgroup *cgroup,
+			     struct cftype *cft,
+			     struct file *file,
+			     const char __user *userbuf,
+			     size_t nbytes, loff_t *unused_ppos)
+{
+	char *buffer;
+	int retval = 0;
+	int value;
+
+	if (nbytes >= PATH_MAX)
+		return -E2BIG;
+
+	/* +1 for nul-terminator */
+	buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;
+
+	if (copy_from_user(buffer, userbuf, nbytes)) {
+		retval = -EFAULT;
+		goto free_buffer;
+	}
+	buffer[nbytes] = 0;	/* nul-terminate */
+	if (sscanf(buffer, "%d", &value) != 1) {
+		retval = -EIO;
+		goto free_buffer;
+	}
+
+	cgroup_lock();
+
+	if (cgroup_is_removed(cgroup)) {
+		retval = -ENODEV;
+		goto unlock;
+	}
+
+	retval = signal_kill(cgroup, value);
+	if (retval == 0)
+		retval = nbytes;
+unlock:
+	cgroup_unlock();
+free_buffer:
+	kfree(buffer);
+	return retval;
+}
+
+static struct cftype kill_file = {
+	.name = "kill",
+	.write = signal_write,
+	.private = 0,
+};
+
+static int signal_populate(struct cgroup_subsys *ss, struct cgroup *cgroup)
+{
+	return cgroup_add_files(cgroup, ss, &kill_file, 1);
+}
+
+struct cgroup_subsys signal_subsys = {
+	.name		= "signal",
+	.create		= signal_create,
+	.destroy	= signal_destroy,
+	.populate	= signal_populate,
+	.subsys_id	= signal_subsys_id,
+	.can_attach	= signal_can_attach,
+	.attach		= NULL,
+	.fork		= NULL,
+	.exit		= NULL,
+};

@@ -328,10 +328,16 @@ config CGROUP_FREEZER
         depends on CGROUPS
         help
           Provides a way to freeze and unfreeze all tasks in a
 	  cgroup
 
+config CGROUP_SIGNAL
+        bool "control group signal subsystem"
+        depends on CGROUPS
+        help
+          Provides a way to signal all tasks in a cgroup
+
 config FAIR_GROUP_SCHED
 	bool "Group scheduling for SCHED_OTHER"
 	depends on GROUP_SCHED
 	default y
 

@@ -47,10 +47,11 @@ obj-$(CONFIG_KEXEC) += kexec.o
 obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
 obj-$(CONFIG_COMPAT) += compat.o
 obj-$(CONFIG_CGROUPS) += cgroup.o
 obj-$(CONFIG_CGROUP_DEBUG) += cgroup_debug.o
 obj-$(CONFIG_CGROUP_FREEZER) += cgroup_freezer.o
+obj-$(CONFIG_CGROUP_SIGNAL) += cgroup_signal.o
 obj-$(CONFIG_CPUSETS) += cpuset.o
 obj-$(CONFIG_CGROUP_NS) += ns_cgroup.o
 obj-$(CONFIG_UTS_NS) += utsname.o
 obj-$(CONFIG_USER_NS) += user_namespace.o
 obj-$(CONFIG_PID_NS) += pid_namespace.o

@@ -52,5 +52,11 @@ SUBSYS(devices)
 #ifdef CONFIG_CGROUP_FREEZER
 SUBSYS(freezer)
 #endif
 
 /* */
+
+#ifdef CONFIG_CGROUP_SIGNAL
+SUBSYS(signal)
+#endif
+
+/* */

---
 include/linux/cgroup_signal.h |   28 +++++++++
 include/linux/cgroup_subsys.h |    6 +
 init/Kconfig                  |    6 +
 kernel/Makefile               |    1 
 kernel/cgroup_signal.c        |  129 ++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 170 insertions(+)
@@ -0,0 +1,28 @@
+#ifndef _LINUX_CGROUP_SIGNAL_H
+#define _LINUX_CGROUP_SIGNAL_H
+/*
+ * cgroup_signal.h -  control group freezer subsystem interface

+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Author : Cedric Le Goater <clg-NmTC/[email protected]>

+ * Author : Matt Helsley <matthltc-r/[email protected]>
+ */
+
+#include <linux/cgroup.h>
+
+#ifdef CONFIG_CGROUP_SIGNAL
+
+struct stateless {
+	struct cgroup_subsys_state css;
+};

	Task A						Task B
---
 include/linux/cgroup_signal.h |   28 +++++++++
 include/linux/cgroup_subsys.h |    6 +
 init/Kconfig                  |    6 +
 kernel/Makefile               |    1 
 kernel/cgroup_signal.c        |  129 ++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 170 insertions(+)
@@ -0,0 +1,28 @@
+#ifndef _LINUX_CGROUP_SIGNAL_H
+#define _LINUX_CGROUP_SIGNAL_H
+/*
+ * cgroup_signal.h -  control group freezer subsystem interface

+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Author : Cedric Le Goater <[email protected]>

+ * Author : Matt Helsley <[email protected]>
+ */
+
+#include <linux/cgroup.h>
+
+#ifdef CONFIG_CGROUP_SIGNAL
+
+struct stateless {
+	struct cgroup_subsys_state css;
+};

	Task A						Task B