1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * kernel/workqueue_internal.h 4 * 5 * Workqueue internal header file. Only to be included by workqueue and 6 * core kernel subsystems. 7 */ 8 #ifndef _KERNEL_WORKQUEUE_INTERNAL_H 9 #define _KERNEL_WORKQUEUE_INTERNAL_H 10 11 #include <linux/workqueue.h> 12 #include <linux/kthread.h> 13 #include <linux/preempt.h> 14 15 struct worker_pool; 16 17 /* 18 * The poor guys doing the actual heavy lifting. All on-duty workers are 19 * either serving the manager role, on idle list or on busy hash. For 20 * details on the locking annotation (L, I, X...), refer to workqueue.c. 21 * 22 * Only to be used in workqueue and async. 23 */ 24 struct worker { 25 /* on idle list while idle, on busy hash table while busy */ 26 union { 27 struct list_head entry; /* L: while idle */ 28 struct hlist_node hentry; /* L: while busy */ 29 }; 30 31 struct work_struct *current_work; /* K: work being processed and its */ 32 work_func_t current_func; /* K: function */ 33 struct pool_workqueue *current_pwq; /* K: pwq */ 34 u64 current_at; /* K: runtime at start or last wakeup */ 35 unsigned long current_start; /* K: start time of current work item */ 36 unsigned int current_color; /* K: color */ 37 38 int sleeping; /* S: is worker sleeping? */ 39 40 /* used by the scheduler to determine a worker's last known identity */ 41 work_func_t last_func; /* K: last work's fn */ 42 43 struct list_head scheduled; /* L: scheduled works */ 44 45 struct task_struct *task; /* I: worker task */ 46 struct worker_pool *pool; /* A: the associated pool */ 47 /* L: for rescuers */ 48 struct list_head node; /* A: anchored at pool->workers */ 49 /* A: runs through worker->node */ 50 51 unsigned long last_active; /* K: last active timestamp */ 52 unsigned int flags; /* L: flags */ 53 int id; /* I: worker id */ 54 55 /* 56 * Opaque string set with work_set_desc(). Printed out with task 57 * dump for debugging - WARN, BUG, panic or sysrq. 58 */ 59 char desc[WORKER_DESC_LEN]; 60 61 /* used only by rescuers to point to the target workqueue */ 62 struct workqueue_struct *rescue_wq; /* I: the workqueue to rescue */ 63 }; 64 65 /** 66 * current_wq_worker - return struct worker if %current is a workqueue worker 67 */ 68 static inline struct worker *current_wq_worker(void) 69 { 70 if (in_task() && (current->flags & PF_WQ_WORKER)) 71 return kthread_data(current); 72 return NULL; 73 } 74 75 /* 76 * Scheduler hooks for concurrency managed workqueue. Only to be used from 77 * sched/ and workqueue.c. 78 */ 79 void wq_worker_running(struct task_struct *task); 80 void wq_worker_sleeping(struct task_struct *task); 81 void wq_worker_tick(struct task_struct *task); 82 work_func_t wq_worker_last_func(struct task_struct *task); 83 84 #endif /* _KERNEL_WORKQUEUE_INTERNAL_H */ 85