1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_KTHREAD_H
3 #define _LINUX_KTHREAD_H
4 /* Simple interface for creating and stopping kernel threads without mess. */
6 #include <linux/sched.h>
11 struct task_struct
*kthread_create_on_node(int (*threadfn
)(void *data
),
14 const char namefmt
[], ...);
17 * kthread_create - create a kthread on the current node
18 * @threadfn: the function to run in the thread
19 * @data: data pointer for @threadfn()
20 * @namefmt: printf-style format string for the thread name
21 * @arg...: arguments for @namefmt.
23 * This macro will create a kthread on the current node, leaving it in
24 * the stopped state. This is just a helper for kthread_create_on_node();
25 * see the documentation there for more details.
27 #define kthread_create(threadfn, data, namefmt, arg...) \
28 kthread_create_on_node(threadfn, data, NUMA_NO_NODE, namefmt, ##arg)
31 struct task_struct
*kthread_create_on_cpu(int (*threadfn
)(void *data
),
36 void kthread_set_per_cpu(struct task_struct
*k
, int cpu
);
37 bool kthread_is_per_cpu(struct task_struct
*k
);
40 * kthread_run - create and wake a thread.
41 * @threadfn: the function to run until signal_pending(current).
42 * @data: data ptr for @threadfn.
43 * @namefmt: printf-style name for the thread.
45 * Description: Convenient wrapper for kthread_create() followed by
46 * wake_up_process(). Returns the kthread or ERR_PTR(-ENOMEM).
48 #define kthread_run(threadfn, data, namefmt, ...) \
50 struct task_struct *__k \
51 = kthread_create(threadfn, data, namefmt, ## __VA_ARGS__); \
53 wake_up_process(__k); \
57 void free_kthread_struct(struct task_struct
*k
);
58 void kthread_bind(struct task_struct
*k
, unsigned int cpu
);
59 void kthread_bind_mask(struct task_struct
*k
, const struct cpumask
*mask
);
60 int kthread_stop(struct task_struct
*k
);
61 bool kthread_should_stop(void);
62 bool kthread_should_park(void);
63 bool __kthread_should_park(struct task_struct
*k
);
64 bool kthread_freezable_should_stop(bool *was_frozen
);
65 void *kthread_func(struct task_struct
*k
);
66 void *kthread_data(struct task_struct
*k
);
67 void *kthread_probe_data(struct task_struct
*k
);
68 int kthread_park(struct task_struct
*k
);
69 void kthread_unpark(struct task_struct
*k
);
70 void kthread_parkme(void);
72 int kthreadd(void *unused
);
73 extern struct task_struct
*kthreadd_task
;
74 extern int tsk_fork_get_node(struct task_struct
*tsk
);
77 * Simple work processor based on kthread.
79 * This provides easier way to make use of kthreads. A kthread_work
80 * can be queued and flushed using queue/kthread_flush_work()
81 * respectively. Queued kthread_works are processed by a kthread
82 * running kthread_worker_fn().
85 typedef void (*kthread_work_func_t
)(struct kthread_work
*work
);
86 void kthread_delayed_work_timer_fn(struct timer_list
*t
);
89 KTW_FREEZABLE
= 1 << 0, /* freeze during suspend */
92 struct kthread_worker
{
95 struct list_head work_list
;
96 struct list_head delayed_work_list
;
97 struct task_struct
*task
;
98 struct kthread_work
*current_work
;
101 struct kthread_work
{
102 struct list_head node
;
103 kthread_work_func_t func
;
104 struct kthread_worker
*worker
;
105 /* Number of canceling calls that are running at the moment. */
109 struct kthread_delayed_work
{
110 struct kthread_work work
;
111 struct timer_list timer
;
114 #define KTHREAD_WORKER_INIT(worker) { \
115 .lock = __RAW_SPIN_LOCK_UNLOCKED((worker).lock), \
116 .work_list = LIST_HEAD_INIT((worker).work_list), \
117 .delayed_work_list = LIST_HEAD_INIT((worker).delayed_work_list),\
120 #define KTHREAD_WORK_INIT(work, fn) { \
121 .node = LIST_HEAD_INIT((work).node), \
125 #define KTHREAD_DELAYED_WORK_INIT(dwork, fn) { \
126 .work = KTHREAD_WORK_INIT((dwork).work, (fn)), \
127 .timer = __TIMER_INITIALIZER(kthread_delayed_work_timer_fn,\
131 #define DEFINE_KTHREAD_WORKER(worker) \
132 struct kthread_worker worker = KTHREAD_WORKER_INIT(worker)
134 #define DEFINE_KTHREAD_WORK(work, fn) \
135 struct kthread_work work = KTHREAD_WORK_INIT(work, fn)
137 #define DEFINE_KTHREAD_DELAYED_WORK(dwork, fn) \
138 struct kthread_delayed_work dwork = \
139 KTHREAD_DELAYED_WORK_INIT(dwork, fn)
142 * kthread_worker.lock needs its own lockdep class key when defined on
143 * stack with lockdep enabled. Use the following macros in such cases.
145 #ifdef CONFIG_LOCKDEP
146 # define KTHREAD_WORKER_INIT_ONSTACK(worker) \
147 ({ kthread_init_worker(&worker); worker; })
148 # define DEFINE_KTHREAD_WORKER_ONSTACK(worker) \
149 struct kthread_worker worker = KTHREAD_WORKER_INIT_ONSTACK(worker)
151 # define DEFINE_KTHREAD_WORKER_ONSTACK(worker) DEFINE_KTHREAD_WORKER(worker)
154 extern void __kthread_init_worker(struct kthread_worker
*worker
,
155 const char *name
, struct lock_class_key
*key
);
157 #define kthread_init_worker(worker) \
159 static struct lock_class_key __key; \
160 __kthread_init_worker((worker), "("#worker")->lock", &__key); \
163 #define kthread_init_work(work, fn) \
165 memset((work), 0, sizeof(struct kthread_work)); \
166 INIT_LIST_HEAD(&(work)->node); \
167 (work)->func = (fn); \
170 #define kthread_init_delayed_work(dwork, fn) \
172 kthread_init_work(&(dwork)->work, (fn)); \
173 timer_setup(&(dwork)->timer, \
174 kthread_delayed_work_timer_fn, \
178 int kthread_worker_fn(void *worker_ptr
);
181 struct kthread_worker
*
182 kthread_create_worker(unsigned int flags
, const char namefmt
[], ...);
184 __printf(3, 4) struct kthread_worker
*
185 kthread_create_worker_on_cpu(int cpu
, unsigned int flags
,
186 const char namefmt
[], ...);
188 bool kthread_queue_work(struct kthread_worker
*worker
,
189 struct kthread_work
*work
);
191 bool kthread_queue_delayed_work(struct kthread_worker
*worker
,
192 struct kthread_delayed_work
*dwork
,
193 unsigned long delay
);
195 bool kthread_mod_delayed_work(struct kthread_worker
*worker
,
196 struct kthread_delayed_work
*dwork
,
197 unsigned long delay
);
199 void kthread_flush_work(struct kthread_work
*work
);
200 void kthread_flush_worker(struct kthread_worker
*worker
);
202 bool kthread_cancel_work_sync(struct kthread_work
*work
);
203 bool kthread_cancel_delayed_work_sync(struct kthread_delayed_work
*work
);
205 void kthread_destroy_worker(struct kthread_worker
*worker
);
207 void kthread_use_mm(struct mm_struct
*mm
);
208 void kthread_unuse_mm(struct mm_struct
*mm
);
210 struct cgroup_subsys_state
;
212 #ifdef CONFIG_BLK_CGROUP
213 void kthread_associate_blkcg(struct cgroup_subsys_state
*css
);
214 struct cgroup_subsys_state
*kthread_blkcg(void);
216 static inline void kthread_associate_blkcg(struct cgroup_subsys_state
*css
) { }
217 static inline struct cgroup_subsys_state
*kthread_blkcg(void)
222 #endif /* _LINUX_KTHREAD_H */