git.sesse.net Git - bcachefs-tools-debian/blob - include/linux/kthread.h

   1 #ifndef _LINUX_KTHREAD_H
   2 #define _LINUX_KTHREAD_H
   3
   4 /* Simple interface for creating and stopping kernel threads without mess. */
   5 #include <linux/err.h>
   6 #include <linux/lockdep.h>
   7 #include <linux/sched.h>
   8 #include <linux/spinlock.h>
   9
  10 __printf(3, 4)
  11 struct task_struct *kthread_create(int (*threadfn)(void *data),
  12                                    void *data,
  13                                    const char namefmt[], ...);
  14
  15
  16 struct task_struct *kthread_create_on_cpu(int (*threadfn)(void *data),
  17                                           void *data,
  18                                           unsigned int cpu,
  19                                           const char *namefmt);
  20
  21 /**
  22  * kthread_run - create and wake a thread.
  23  * @threadfn: the function to run until signal_pending(current).
  24  * @data: data ptr for @threadfn.
  25  * @namefmt: printf-style name for the thread.
  26  *
  27  * Description: Convenient wrapper for kthread_create() followed by
  28  * wake_up_process().  Returns the kthread or ERR_PTR(-ENOMEM).
  29  */
  30 #define kthread_run(threadfn, data, namefmt, ...)                          \
  31 ({                                                                         \
  32         struct task_struct *__k                                            \
  33                 = kthread_create(threadfn, data, namefmt, ## __VA_ARGS__); \
  34         if (!IS_ERR(__k))                                                  \
  35                 wake_up_process(__k);                                      \
  36         __k;                                                               \
  37 })
  38
  39 int kthread_stop(struct task_struct *k);
  40 bool kthread_should_stop(void);
  41 bool kthread_should_park(void);
  42 bool kthread_freezable_should_stop(bool *was_frozen);
  43 void *kthread_data(struct task_struct *k);
  44 void *probe_kthread_data(struct task_struct *k);
  45 int kthread_park(struct task_struct *k);
  46 void kthread_unpark(struct task_struct *k);
  47 void kthread_parkme(void);
  48
  49 int kthreadd(void *unused);
  50 extern struct task_struct *kthreadd_task;
  51 extern int tsk_fork_get_node(struct task_struct *tsk);
  52
  53 /*
  54  * Simple work processor based on kthread.
  55  *
  56  * This provides easier way to make use of kthreads.  A kthread_work
  57  * can be queued and flushed using queue/flush_kthread_work()
  58  * respectively.  Queued kthread_works are processed by a kthread
  59  * running kthread_worker_fn().
  60  */
  61 struct kthread_work;
  62 typedef void (*kthread_work_func_t)(struct kthread_work *work);
  63
  64 struct kthread_worker {
  65         spinlock_t              lock;
  66         struct list_head        work_list;
  67         struct task_struct      *task;
  68         struct kthread_work     *current_work;
  69 };
  70
  71 struct kthread_work {
  72         struct list_head        node;
  73         kthread_work_func_t     func;
  74         struct kthread_worker   *worker;
  75 };
  76
  77 #define KTHREAD_WORKER_INIT(worker)     {                               \
  78         .lock = __SPIN_LOCK_UNLOCKED((worker).lock),                    \
  79         .work_list = LIST_HEAD_INIT((worker).work_list),                \
  80         }
  81
  82 #define KTHREAD_WORK_INIT(work, fn)     {                               \
  83         .node = LIST_HEAD_INIT((work).node),                            \
  84         .func = (fn),                                                   \
  85         }
  86
  87 #define DEFINE_KTHREAD_WORKER(worker)                                   \
  88         struct kthread_worker worker = KTHREAD_WORKER_INIT(worker)
  89
  90 #define DEFINE_KTHREAD_WORK(work, fn)                                   \
  91         struct kthread_work work = KTHREAD_WORK_INIT(work, fn)
  92
  93 #define DEFINE_KTHREAD_WORKER_ONSTACK(worker) DEFINE_KTHREAD_WORKER(worker)
  94
  95 extern void __init_kthread_worker(struct kthread_worker *worker,
  96                         const char *name, struct lock_class_key *key);
  97
  98 #define init_kthread_worker(worker)                                     \
  99         do {                                                            \
 100                 static struct lock_class_key __key;                     \
 101                 __init_kthread_worker((worker), "("#worker")->lock", &__key); \
 102         } while (0)
 103
 104 #define init_kthread_work(work, fn)                                     \
 105         do {                                                            \
 106                 memset((work), 0, sizeof(struct kthread_work));         \
 107                 INIT_LIST_HEAD(&(work)->node);                          \
 108                 (work)->func = (fn);                                    \
 109         } while (0)
 110
 111 int kthread_worker_fn(void *worker_ptr);
 112
 113 bool queue_kthread_work(struct kthread_worker *worker,
 114                         struct kthread_work *work);
 115 void flush_kthread_work(struct kthread_work *work);
 116 void flush_kthread_worker(struct kthread_worker *worker);
 117
 118 #endif /* _LINUX_KTHREAD_H */