container freezer: make refrigerator always available

Now that the TIF_FREEZE flag is available in all architectures, extract
the refrigerator() and freeze_task() from kernel/power/process.c and make
it available to all.

The refrigerator() can now be used in a control group subsystem
implementing a control group freezer.

Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Tested-by: Matt Helsley <matthltc@us.ibm.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 11 insertions, 3 deletions

diff --git a/include/linux/freezer.h b/include/linux/freezer.h
index deddeedf3257..17e3bb42dd3c 100644
--- a/include/linux/freezer.h
+++ b/include/linux/freezer.h
@@ -6,7 +6,7 @@
 #include <linux/sched.h>
 #include <linux/wait.h>
 
-#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_FREEZER
 /*
  * Check if a process has been frozen
  */
@@ -39,6 +39,11 @@ static inline void clear_freeze_flag(struct task_struct *p)
         clear_tsk_thread_flag(p, TIF_FREEZE);
 }
 
+static inline bool should_send_signal(struct task_struct *p)
+{
+        return !(p->flags & PF_FREEZER_NOSIG);
+}
+
 /*
  * Wake up a frozen process
  *
@@ -75,6 +80,9 @@ static inline int try_to_freeze(void)
                 return 0;
 }
 
+extern bool freeze_task(struct task_struct *p, bool sig_only);
+extern void cancel_freezing(struct task_struct *p);
+
 /*
  * 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
@@ -166,7 +174,7 @@ static inline void set_freezable_with_signal(void)
         } while (try_to_freeze());                                      \
         __retval;                                                       \
 })
-#else /* !CONFIG_PM_SLEEP */
+#else /* !CONFIG_FREEZER */
 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) {}
@@ -191,6 +199,6 @@ static inline void set_freezable_with_signal(void) {}
 #define wait_event_freezable_timeout(wq, condition, timeout)            \
                 wait_event_interruptible_timeout(wq, condition, timeout)
 
-#endif /* !CONFIG_PM_SLEEP */
+#endif /* !CONFIG_FREEZER */
 
 #endif  /* FREEZER_H_INCLUDED */