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; /* L: work being processed */ 32 work_func_t current_func; /* L: current_work's fn */ 33 struct pool_workqueue *current_pwq; /* L: current_work's pwq */ 34 struct list_head scheduled; /* L: scheduled works */ 35 36 /* 64 bytes boundary on 64bit, 32 on 32bit */ 37 38 struct task_struct *task; /* I: worker task */ 39 struct worker_pool *pool; /* A: the associated pool */ 40 /* L: for rescuers */ 41 struct list_head node; /* A: anchored at pool->workers */ 42 /* A: runs through worker->node */ 43 44 unsigned long last_active; /* L: last active timestamp */ 45 unsigned int flags; /* X: flags */ 46 int id; /* I: worker id */ 47 48 /* 49 * Opaque string set with work_set_desc(). Printed out with task 50 * dump for debugging - WARN, BUG, panic or sysrq. 51 */ 52 char desc[WORKER_DESC_LEN]; 53 54 /* used only by rescuers to point to the target workqueue */ 55 struct workqueue_struct *rescue_wq; /* I: the workqueue to rescue */ 56 57 /* used by the scheduler to determine a worker's last known identity */ 58 work_func_t last_func; 59 }; 60 61 /** 62 * current_wq_worker - return struct worker if %current is a workqueue worker 63 */ 64 static inline struct worker *current_wq_worker(void) 65 { 66 if (in_task() && (current->flags & PF_WQ_WORKER)) 67 return kthread_data(current); 68 return NULL; 69 } 70 71 /* 72 * Scheduler hooks for concurrency managed workqueue. Only to be used from 73 * sched/ and workqueue.c. 74 */ 75 void wq_worker_waking_up(struct task_struct *task, int cpu); 76 struct task_struct *wq_worker_sleeping(struct task_struct *task); 77 work_func_t wq_worker_last_func(struct task_struct *task); 78 79 #endif /* _KERNEL_WORKQUEUE_INTERNAL_H */ 80