diff options
Diffstat (limited to 'ANDROID_3.4.5/include/linux/freezer.h')
| -rw-r--r-- | ANDROID_3.4.5/include/linux/freezer.h | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/ANDROID_3.4.5/include/linux/freezer.h b/ANDROID_3.4.5/include/linux/freezer.h new file mode 100644 index 00000000..a628084e --- /dev/null +++ b/ANDROID_3.4.5/include/linux/freezer.h @@ -0,0 +1,214 @@ +/* Freezer declarations */ + +#ifndef FREEZER_H_INCLUDED +#define FREEZER_H_INCLUDED + +#include <linux/sched.h> +#include <linux/wait.h> +#include <linux/atomic.h> + +#ifdef CONFIG_FREEZER +extern atomic_t system_freezing_cnt; /* nr of freezing conds in effect */ +extern bool pm_freezing; /* PM freezing in effect */ +extern bool pm_nosig_freezing; /* PM nosig freezing in effect */ + +/* + * Check if a process has been frozen + */ +static inline bool frozen(struct task_struct *p) +{ + return p->flags & PF_FROZEN; +} + +extern bool freezing_slow_path(struct task_struct *p); + +/* + * Check if there is a request to freeze a process + */ +static inline bool freezing(struct task_struct *p) +{ + if (likely(!atomic_read(&system_freezing_cnt))) + return false; + return freezing_slow_path(p); +} + +/* Takes and releases task alloc lock using task_lock() */ +extern void __thaw_task(struct task_struct *t); + +extern bool __refrigerator(bool check_kthr_stop); +extern int freeze_processes(void); +extern int freeze_kernel_threads(void); +extern void thaw_processes(void); +extern void thaw_kernel_threads(void); + +/* + * HACK: prevent sleeping while atomic warnings due to ARM signal handling + * disabling irqs + */ +static inline bool try_to_freeze_nowarn(void) +{ + if (likely(!freezing(current))) + return false; + return __refrigerator(false); +} + +static inline bool try_to_freeze(void) +{ + might_sleep(); + if (likely(!freezing(current))) + return false; + return __refrigerator(false); +} + +extern bool freeze_task(struct task_struct *p); +extern bool set_freezable(void); + +#ifdef CONFIG_CGROUP_FREEZER +extern bool cgroup_freezing(struct task_struct *task); +#else /* !CONFIG_CGROUP_FREEZER */ +static inline bool cgroup_freezing(struct task_struct *task) +{ + return false; +} +#endif /* !CONFIG_CGROUP_FREEZER */ + +/* + * 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 + * complete. However, we don't want kernel threads to be frozen in unexpected + * places, so we allow them to block freeze_processes() instead or to set + * PF_NOFREEZE if needed. Fortunately, in the ____call_usermodehelper() case the + * parent won't really block freeze_processes(), since ____call_usermodehelper() + * (the child) does a little before exec/exit and it can't be frozen before + * waking up the parent. + */ + + +/* Tell the freezer not to count the current task as freezable. */ +static inline void freezer_do_not_count(void) +{ + current->flags |= PF_FREEZER_SKIP; +} + +/* + * Tell the freezer to count the current task as freezable again and try to + * freeze it. + */ +static inline void freezer_count(void) +{ + current->flags &= ~PF_FREEZER_SKIP; + try_to_freeze(); +} + +/* + * Check if the task should be counted as freezable by the freezer + */ +static inline int freezer_should_skip(struct task_struct *p) +{ + return !!(p->flags & PF_FREEZER_SKIP); +} + +/* + * These macros are intended to be used whenever you want allow a task that's + * sleeping in TASK_UNINTERRUPTIBLE or TASK_KILLABLE state to be frozen. Note + * that neither return any clear indication of whether a freeze event happened + * while in this function. + */ + +/* Like schedule(), but should not block the freezer. */ +#define freezable_schedule() \ +({ \ + freezer_do_not_count(); \ + schedule(); \ + freezer_count(); \ +}) + +/* Like schedule_timeout_killable(), but should not block the freezer. */ +#define freezable_schedule_timeout_killable(timeout) \ +({ \ + long __retval; \ + freezer_do_not_count(); \ + __retval = schedule_timeout_killable(timeout); \ + freezer_count(); \ + __retval; \ +}) + +/* + * Freezer-friendly wrappers around wait_event_interruptible(), + * wait_event_killable() and wait_event_interruptible_timeout(), originally + * defined in <linux/wait.h> + */ + +#define wait_event_freezekillable(wq, condition) \ +({ \ + int __retval; \ + freezer_do_not_count(); \ + __retval = wait_event_killable(wq, (condition)); \ + freezer_count(); \ + __retval; \ +}) + +#define wait_event_freezable(wq, condition) \ +({ \ + int __retval; \ + for (;;) { \ + __retval = wait_event_interruptible(wq, \ + (condition) || freezing(current)); \ + if (__retval || (condition)) \ + break; \ + try_to_freeze(); \ + } \ + __retval; \ +}) + +#define wait_event_freezable_timeout(wq, condition, timeout) \ +({ \ + long __retval = timeout; \ + for (;;) { \ + __retval = wait_event_interruptible_timeout(wq, \ + (condition) || freezing(current), \ + __retval); \ + if (__retval <= 0 || (condition)) \ + break; \ + try_to_freeze(); \ + } \ + __retval; \ +}) + +#else /* !CONFIG_FREEZER */ +static inline bool frozen(struct task_struct *p) { return false; } +static inline bool freezing(struct task_struct *p) { return false; } +static inline void __thaw_task(struct task_struct *t) {} + +static inline bool __refrigerator(bool check_kthr_stop) { return false; } +static inline int freeze_processes(void) { return -ENOSYS; } +static inline int freeze_kernel_threads(void) { return -ENOSYS; } +static inline void thaw_processes(void) {} +static inline void thaw_kernel_threads(void) {} + +static inline bool try_to_freeze(void) { return false; } + +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) {} + +#define freezable_schedule() schedule() + +#define freezable_schedule_timeout_killable(timeout) \ + schedule_timeout_killable(timeout) + +#define wait_event_freezable(wq, condition) \ + wait_event_interruptible(wq, condition) + +#define wait_event_freezable_timeout(wq, condition, timeout) \ + wait_event_interruptible_timeout(wq, condition, timeout) + +#define wait_event_freezekillable(wq, condition) \ + wait_event_killable(wq, condition) + +#endif /* !CONFIG_FREEZER */ + +#endif /* FREEZER_H_INCLUDED */ |