/* Freezer declarations */ #include #ifdef CONFIG_PM /* * Check if a process has been frozen */ static inline int frozen(struct task_struct *p) { return p->flags & PF_FROZEN; } /* * Check if there is a request to freeze a process */ static inline int freezing(struct task_struct *p) { return test_tsk_thread_flag(p, TIF_FREEZE); } /* * Request that a process be frozen */ static inline void freeze(struct task_struct *p) { set_tsk_thread_flag(p, TIF_FREEZE); } /* * Sometimes we may need to cancel the previous 'freeze' request */ static inline void do_not_freeze(struct task_struct *p) { clear_tsk_thread_flag(p, TIF_FREEZE); } /* * Wake up a frozen process * * task_lock() is taken to prevent the race with refrigerator() which may * occur if the freezing of tasks fails. Namely, without the lock, if the * freezing of tasks failed, thaw_tasks() might have run before a task in * refrigerator() could call frozen_process(), in which case the task would be * frozen and no one would thaw it. */ static inline int thaw_process(struct task_struct *p) { task_lock(p); if (frozen(p)) { p->flags &= ~PF_FROZEN; task_unlock(p); wake_up_process(p); return 1; } clear_tsk_thread_flag(p, TIF_FREEZE); task_unlock(p); return 0; } /* * freezing is complete, mark process as frozen */ static inline void frozen_process(struct task_struct *p) { p->flags |= PF_FROZEN; wmb(); clear_tsk_thread_flag(p, TIF_FREEZE); } 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 void thaw_some_processes(int all); #else static inline int frozen(struct task_struct *p) { return 0; } static inline int freezing(struct task_struct *p) { return 0; } static inline void freeze(struct task_struct *p) { BUG(); } static inline int thaw_process(struct task_struct *p) { return 1; } static inline void frozen_process(struct task_struct *p) { BUG(); } 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; } #endif