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 unsigned int current_color; /* K: color */ 35 36 int sleeping; /* S: is worker sleeping? */ 37 38 /* used by the scheduler to determine a worker's last known identity */ 39 work_func_t last_func; /* K: last work's fn */ 40 41 struct list_head scheduled; /* L: scheduled works */ 42 43 struct task_struct *task; /* I: worker task */ 44 struct worker_pool *pool; /* A: the associated pool */ 45 /* L: for rescuers */ 46 struct list_head node; /* A: anchored at pool->workers */ 47 /* A: runs through worker->node */ 48 49 unsigned long last_active; /* K: last active timestamp */ 50 unsigned int flags; /* X: flags */ 51 int id; /* I: worker id */ 52 53 /* 54 * Opaque string set with work_set_desc(). Printed out with task 55 * dump for debugging - WARN, BUG, panic or sysrq. 56 */ 57 char desc[WORKER_DESC_LEN]; 58 59 /* used only by rescuers to point to the target workqueue */ 60 struct workqueue_struct *rescue_wq; /* I: the workqueue to rescue */ 61 }; 62 63 /** 64 * current_wq_worker - return struct worker if %current is a workqueue worker 65 */ 66 static inline struct worker *current_wq_worker(void) 67 { 68 if (in_task() && (current->flags & PF_WQ_WORKER)) 69 return kthread_data(current); 70 return NULL; 71 } 72 73 /* 74 * Scheduler hooks for concurrency managed workqueue. Only to be used from 75 * sched/ and workqueue.c. 76 */ 77 void wq_worker_running(struct task_struct *task); 78 void wq_worker_sleeping(struct task_struct *task); 79 work_func_t wq_worker_last_func(struct task_struct *task); 80 81 #endif /* _KERNEL_WORKQUEUE_INTERNAL_H */ 82