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#ifndef _LINUX_KTHREAD_H
#define _LINUX_KTHREAD_H
/* Simple interface for creating and stopping kernel threads without mess. */
#include <linux/err.h>
#include <linux/sched.h>
struct task_struct *kthread_create(int (*threadfn)(void *data),
void *data,
const char namefmt[], ...)
__attribute__((format(printf, 3, 4)));
/**
* kthread_run - create and wake a thread.
* @threadfn: the function to run until signal_pending(current).
* @data: data ptr for @threadfn.
* @namefmt: printf-style name for the thread.
*
* Description: Convenient wrapper for kthread_create() followed by
* wake_up_process(). Returns the kthread or ERR_PTR(-ENOMEM).
*/
#define kthread_run(threadfn, data, namefmt, ...) \
({ \
struct task_struct *__k \
= kthread_create(threadfn, data, namefmt, ## __VA_ARGS__); \
if (!IS_ERR(__k)) \
wake_up_process(__k); \
__k; \
})
void kthread_bind(struct task_struct *k, unsigned int cpu);
int kthread_stop(struct task_struct *k);
int kthread_should_stop(void);
void *kthread_data(struct task_struct *k);
int kthreadd(void *unused);
extern struct task_struct *kthreadd_task;
/*
* Simple work processor based on kthread.
*
* This provides easier way to make use of kthreads. A kthread_work
* can be queued and flushed using queue/flush_kthread_work()
* respectively. Queued kthread_works are processed by a kthread
* running kthread_worker_fn().
*
* A kthread_work can't be freed while it is executing.
*/
struct kthread_work;
typedef void (*kthread_work_func_t)(struct kthread_work *work);
struct kthread_worker {
spinlock_t lock;
struct list_head work_list;
struct task_struct *task;
};
struct kthread_work {
struct list_head node;
kthread_work_func_t func;
wait_queue_head_t done;
atomic_t flushing;
int queue_seq;
int done_seq;
};
#define KTHREAD_WORKER_INIT(worker) { \
.lock = __SPIN_LOCK_UNLOCKED((worker).lock), \
.work_list = LIST_HEAD_INIT((worker).work_list), \
}
#define KTHREAD_WORK_INIT(work, fn) { \
.node = LIST_HEAD_INIT((work).node), \
.func = (fn), \
.done = __WAIT_QUEUE_HEAD_INITIALIZER((work).done), \
.flushing = ATOMIC_INIT(0), \
}
#define DEFINE_KTHREAD_WORKER(worker) \
struct kthread_worker worker = KTHREAD_WORKER_INIT(worker)
#define DEFINE_KTHREAD_WORK(work, fn) \
struct kthread_work work = KTHREAD_WORK_INIT(work, fn)
/*
* kthread_worker.lock and kthread_work.done need their own lockdep class
* keys if they are defined on stack with lockdep enabled. Use the
* following macros when defining them on stack.
*/
#ifdef CONFIG_LOCKDEP
# define KTHREAD_WORKER_INIT_ONSTACK(worker) \
({ init_kthread_worker(&worker); worker; })
# define DEFINE_KTHREAD_WORKER_ONSTACK(worker) \
struct kthread_worker worker = KTHREAD_WORKER_INIT_ONSTACK(worker)
# define KTHREAD_WORK_INIT_ONSTACK(work, fn) \
({ init_kthread_work((&work), fn); work; })
# define DEFINE_KTHREAD_WORK_ONSTACK(work, fn) \
struct kthread_work work = KTHREAD_WORK_INIT_ONSTACK(work, fn)
#else
# define DEFINE_KTHREAD_WORKER_ONSTACK(worker) DEFINE_KTHREAD_WORKER(worker)
# define DEFINE_KTHREAD_WORK_ONSTACK(work, fn) DEFINE_KTHREAD_WORK(work, fn)
#endif
extern void __init_kthread_worker(struct kthread_worker *worker,
const char *name, struct lock_class_key *key);
#define init_kthread_worker(worker) \
do { \
static struct lock_class_key __key; \
__init_kthread_worker((worker), "("#worker")->lock", &__key); \
} while (0)
#define init_kthread_work(work, fn) \
do { \
memset((work), 0, sizeof(struct kthread_work)); \
INIT_LIST_HEAD(&(work)->node); \
(work)->func = (fn); \
init_waitqueue_head(&(work)->done); \
} while (0)
int kthread_worker_fn(void *worker_ptr);
bool queue_kthread_work(struct kthread_worker *worker,
struct kthread_work *work);
void flush_kthread_work(struct kthread_work *work);
void flush_kthread_worker(struct kthread_worker *worker);
#endif /* _LINUX_KTHREAD_H */
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