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Diffstat (limited to '')
-rw-r--r-- | include/linux/kthread.h | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/include/linux/kthread.h b/include/linux/kthread.h new file mode 100644 index 000000000..2484ed97e --- /dev/null +++ b/include/linux/kthread.h @@ -0,0 +1,222 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#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 mm_struct; + +__printf(4, 5) +struct task_struct *kthread_create_on_node(int (*threadfn)(void *data), + void *data, + int node, + const char namefmt[], ...); + +/** + * kthread_create - create a kthread on the current node + * @threadfn: the function to run in the thread + * @data: data pointer for @threadfn() + * @namefmt: printf-style format string for the thread name + * @arg...: arguments for @namefmt. + * + * This macro will create a kthread on the current node, leaving it in + * the stopped state. This is just a helper for kthread_create_on_node(); + * see the documentation there for more details. + */ +#define kthread_create(threadfn, data, namefmt, arg...) \ + kthread_create_on_node(threadfn, data, NUMA_NO_NODE, namefmt, ##arg) + + +struct task_struct *kthread_create_on_cpu(int (*threadfn)(void *data), + void *data, + unsigned int cpu, + const char *namefmt); + +void kthread_set_per_cpu(struct task_struct *k, int cpu); +bool kthread_is_per_cpu(struct task_struct *k); + +/** + * 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 free_kthread_struct(struct task_struct *k); +void kthread_bind(struct task_struct *k, unsigned int cpu); +void kthread_bind_mask(struct task_struct *k, const struct cpumask *mask); +int kthread_stop(struct task_struct *k); +bool kthread_should_stop(void); +bool kthread_should_park(void); +bool __kthread_should_park(struct task_struct *k); +bool kthread_freezable_should_stop(bool *was_frozen); +void *kthread_func(struct task_struct *k); +void *kthread_data(struct task_struct *k); +void *kthread_probe_data(struct task_struct *k); +int kthread_park(struct task_struct *k); +void kthread_unpark(struct task_struct *k); +void kthread_parkme(void); + +int kthreadd(void *unused); +extern struct task_struct *kthreadd_task; +extern int tsk_fork_get_node(struct task_struct *tsk); + +/* + * 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/kthread_flush_work() + * respectively. Queued kthread_works are processed by a kthread + * running kthread_worker_fn(). + */ +struct kthread_work; +typedef void (*kthread_work_func_t)(struct kthread_work *work); +void kthread_delayed_work_timer_fn(struct timer_list *t); + +enum { + KTW_FREEZABLE = 1 << 0, /* freeze during suspend */ +}; + +struct kthread_worker { + unsigned int flags; + raw_spinlock_t lock; + struct list_head work_list; + struct list_head delayed_work_list; + struct task_struct *task; + struct kthread_work *current_work; +}; + +struct kthread_work { + struct list_head node; + kthread_work_func_t func; + struct kthread_worker *worker; + /* Number of canceling calls that are running at the moment. */ + int canceling; +}; + +struct kthread_delayed_work { + struct kthread_work work; + struct timer_list timer; +}; + +#define KTHREAD_WORKER_INIT(worker) { \ + .lock = __RAW_SPIN_LOCK_UNLOCKED((worker).lock), \ + .work_list = LIST_HEAD_INIT((worker).work_list), \ + .delayed_work_list = LIST_HEAD_INIT((worker).delayed_work_list),\ + } + +#define KTHREAD_WORK_INIT(work, fn) { \ + .node = LIST_HEAD_INIT((work).node), \ + .func = (fn), \ + } + +#define KTHREAD_DELAYED_WORK_INIT(dwork, fn) { \ + .work = KTHREAD_WORK_INIT((dwork).work, (fn)), \ + .timer = __TIMER_INITIALIZER(kthread_delayed_work_timer_fn,\ + TIMER_IRQSAFE), \ + } + +#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) + +#define DEFINE_KTHREAD_DELAYED_WORK(dwork, fn) \ + struct kthread_delayed_work dwork = \ + KTHREAD_DELAYED_WORK_INIT(dwork, fn) + +/* + * kthread_worker.lock needs its own lockdep class key when defined on + * stack with lockdep enabled. Use the following macros in such cases. + */ +#ifdef CONFIG_LOCKDEP +# define KTHREAD_WORKER_INIT_ONSTACK(worker) \ + ({ kthread_init_worker(&worker); worker; }) +# define DEFINE_KTHREAD_WORKER_ONSTACK(worker) \ + struct kthread_worker worker = KTHREAD_WORKER_INIT_ONSTACK(worker) +#else +# define DEFINE_KTHREAD_WORKER_ONSTACK(worker) DEFINE_KTHREAD_WORKER(worker) +#endif + +extern void __kthread_init_worker(struct kthread_worker *worker, + const char *name, struct lock_class_key *key); + +#define kthread_init_worker(worker) \ + do { \ + static struct lock_class_key __key; \ + __kthread_init_worker((worker), "("#worker")->lock", &__key); \ + } while (0) + +#define kthread_init_work(work, fn) \ + do { \ + memset((work), 0, sizeof(struct kthread_work)); \ + INIT_LIST_HEAD(&(work)->node); \ + (work)->func = (fn); \ + } while (0) + +#define kthread_init_delayed_work(dwork, fn) \ + do { \ + kthread_init_work(&(dwork)->work, (fn)); \ + timer_setup(&(dwork)->timer, \ + kthread_delayed_work_timer_fn, \ + TIMER_IRQSAFE); \ + } while (0) + +int kthread_worker_fn(void *worker_ptr); + +__printf(2, 3) +struct kthread_worker * +kthread_create_worker(unsigned int flags, const char namefmt[], ...); + +__printf(3, 4) struct kthread_worker * +kthread_create_worker_on_cpu(int cpu, unsigned int flags, + const char namefmt[], ...); + +bool kthread_queue_work(struct kthread_worker *worker, + struct kthread_work *work); + +bool kthread_queue_delayed_work(struct kthread_worker *worker, + struct kthread_delayed_work *dwork, + unsigned long delay); + +bool kthread_mod_delayed_work(struct kthread_worker *worker, + struct kthread_delayed_work *dwork, + unsigned long delay); + +void kthread_flush_work(struct kthread_work *work); +void kthread_flush_worker(struct kthread_worker *worker); + +bool kthread_cancel_work_sync(struct kthread_work *work); +bool kthread_cancel_delayed_work_sync(struct kthread_delayed_work *work); + +void kthread_destroy_worker(struct kthread_worker *worker); + +void kthread_use_mm(struct mm_struct *mm); +void kthread_unuse_mm(struct mm_struct *mm); + +struct cgroup_subsys_state; + +#ifdef CONFIG_BLK_CGROUP +void kthread_associate_blkcg(struct cgroup_subsys_state *css); +struct cgroup_subsys_state *kthread_blkcg(void); +#else +static inline void kthread_associate_blkcg(struct cgroup_subsys_state *css) { } +static inline struct cgroup_subsys_state *kthread_blkcg(void) +{ + return NULL; +} +#endif +#endif /* _LINUX_KTHREAD_H */ |