1#ifndef _LINUX_KTHREAD_H 2#define _LINUX_KTHREAD_H 3/* Simple interface for creating and stopping kernel threads without mess. */ 4#include <linux/err.h> 5#include <linux/sched.h> 6 7__printf(4, 5) 8struct task_struct *kthread_create_on_node(int (*threadfn)(void *data), 9 void *data, 10 int node, 11 const char namefmt[], ...); 12 13#define kthread_create(threadfn, data, namefmt, arg...) \ 14 kthread_create_on_node(threadfn, data, -1, namefmt, ##arg) 15 16 17struct task_struct *kthread_create_on_cpu(int (*threadfn)(void *data), 18 void *data, 19 unsigned int cpu, 20 const char *namefmt); 21 22/** 23 * kthread_run - create and wake a thread. 24 * @threadfn: the function to run until signal_pending(current). 25 * @data: data ptr for @threadfn. 26 * @namefmt: printf-style name for the thread. 27 * 28 * Description: Convenient wrapper for kthread_create() followed by 29 * wake_up_process(). Returns the kthread or ERR_PTR(-ENOMEM). 30 */ 31#define kthread_run(threadfn, data, namefmt, ...) \ 32({ \ 33 struct task_struct *__k \ 34 = kthread_create(threadfn, data, namefmt, ## __VA_ARGS__); \ 35 if (!IS_ERR(__k)) \ 36 wake_up_process(__k); \ 37 __k; \ 38}) 39 40void kthread_bind(struct task_struct *k, unsigned int cpu); 41int kthread_stop(struct task_struct *k); 42bool kthread_should_stop(void); 43bool kthread_should_park(void); 44bool kthread_freezable_should_stop(bool *was_frozen); 45void *kthread_data(struct task_struct *k); 46void *probe_kthread_data(struct task_struct *k); 47int kthread_park(struct task_struct *k); 48void kthread_unpark(struct task_struct *k); 49void kthread_parkme(void); 50 51int kthreadd(void *unused); 52extern struct task_struct *kthreadd_task; 53extern int tsk_fork_get_node(struct task_struct *tsk); 54 55/* 56 * Simple work processor based on kthread. 57 * 58 * This provides easier way to make use of kthreads. A kthread_work 59 * can be queued and flushed using queue/flush_kthread_work() 60 * respectively. Queued kthread_works are processed by a kthread 61 * running kthread_worker_fn(). 62 */ 63struct kthread_work; 64typedef void (*kthread_work_func_t)(struct kthread_work *work); 65 66struct kthread_worker { 67 spinlock_t lock; 68 struct list_head work_list; 69 struct task_struct *task; 70 struct kthread_work *current_work; 71}; 72 73struct kthread_work { 74 struct list_head node; 75 kthread_work_func_t func; 76 struct kthread_worker *worker; 77}; 78 79#define KTHREAD_WORKER_INIT(worker) { \ 80 .lock = __SPIN_LOCK_UNLOCKED((worker).lock), \ 81 .work_list = LIST_HEAD_INIT((worker).work_list), \ 82 } 83 84#define KTHREAD_WORK_INIT(work, fn) { \ 85 .node = LIST_HEAD_INIT((work).node), \ 86 .func = (fn), \ 87 } 88 89#define DEFINE_KTHREAD_WORKER(worker) \ 90 struct kthread_worker worker = KTHREAD_WORKER_INIT(worker) 91 92#define DEFINE_KTHREAD_WORK(work, fn) \ 93 struct kthread_work work = KTHREAD_WORK_INIT(work, fn) 94 95/* 96 * kthread_worker.lock needs its own lockdep class key when defined on 97 * stack with lockdep enabled. Use the following macros in such cases. 98 */ 99#ifdef CONFIG_LOCKDEP 100# define KTHREAD_WORKER_INIT_ONSTACK(worker) \ 101 ({ init_kthread_worker(&worker); worker; }) 102# define DEFINE_KTHREAD_WORKER_ONSTACK(worker) \ 103 struct kthread_worker worker = KTHREAD_WORKER_INIT_ONSTACK(worker) 104#else 105# define DEFINE_KTHREAD_WORKER_ONSTACK(worker) DEFINE_KTHREAD_WORKER(worker) 106#endif 107 108extern void __init_kthread_worker(struct kthread_worker *worker, 109 const char *name, struct lock_class_key *key); 110 111#define init_kthread_worker(worker) \ 112 do { \ 113 static struct lock_class_key __key; \ 114 __init_kthread_worker((worker), "("#worker")->lock", &__key); \ 115 } while (0) 116 117#define init_kthread_work(work, fn) \ 118 do { \ 119 memset((work), 0, sizeof(struct kthread_work)); \ 120 INIT_LIST_HEAD(&(work)->node); \ 121 (work)->func = (fn); \ 122 } while (0) 123 124int kthread_worker_fn(void *worker_ptr); 125 126bool queue_kthread_work(struct kthread_worker *worker, 127 struct kthread_work *work); 128void flush_kthread_work(struct kthread_work *work); 129void flush_kthread_worker(struct kthread_worker *worker); 130 131#endif /* _LINUX_KTHREAD_H */ 132