1 /* 2 * workqueue.h --- work queue handling for Linux. 3 */ 4 5 #ifndef _LINUX_WORKQUEUE_H 6 #define _LINUX_WORKQUEUE_H 7 8 #include <linux/timer.h> 9 #include <linux/linkage.h> 10 #include <linux/bitops.h> 11 #include <asm/atomic.h> 12 13 struct workqueue_struct; 14 15 struct work_struct; 16 typedef void (*work_func_t)(struct work_struct *work); 17 18 /* 19 * The first word is the work queue pointer and the flags rolled into 20 * one 21 */ 22 #define work_data_bits(work) ((unsigned long *)(&(work)->data)) 23 24 struct work_struct { 25 atomic_long_t data; 26 #define WORK_STRUCT_PENDING 0 /* T if work item pending execution */ 27 #define WORK_STRUCT_NOAUTOREL 1 /* F if work item automatically released on exec */ 28 #define WORK_STRUCT_FLAG_MASK (3UL) 29 #define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK) 30 struct list_head entry; 31 work_func_t func; 32 }; 33 34 #define WORK_DATA_INIT(autorelease) \ 35 ATOMIC_LONG_INIT((autorelease) << WORK_STRUCT_NOAUTOREL) 36 37 struct delayed_work { 38 struct work_struct work; 39 struct timer_list timer; 40 }; 41 42 struct execute_work { 43 struct work_struct work; 44 }; 45 46 #define __WORK_INITIALIZER(n, f) { \ 47 .data = WORK_DATA_INIT(0), \ 48 .entry = { &(n).entry, &(n).entry }, \ 49 .func = (f), \ 50 } 51 52 #define __WORK_INITIALIZER_NAR(n, f) { \ 53 .data = WORK_DATA_INIT(1), \ 54 .entry = { &(n).entry, &(n).entry }, \ 55 .func = (f), \ 56 } 57 58 #define __DELAYED_WORK_INITIALIZER(n, f) { \ 59 .work = __WORK_INITIALIZER((n).work, (f)), \ 60 .timer = TIMER_INITIALIZER(NULL, 0, 0), \ 61 } 62 63 #define __DELAYED_WORK_INITIALIZER_NAR(n, f) { \ 64 .work = __WORK_INITIALIZER_NAR((n).work, (f)), \ 65 .timer = TIMER_INITIALIZER(NULL, 0, 0), \ 66 } 67 68 #define DECLARE_WORK(n, f) \ 69 struct work_struct n = __WORK_INITIALIZER(n, f) 70 71 #define DECLARE_WORK_NAR(n, f) \ 72 struct work_struct n = __WORK_INITIALIZER_NAR(n, f) 73 74 #define DECLARE_DELAYED_WORK(n, f) \ 75 struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f) 76 77 #define DECLARE_DELAYED_WORK_NAR(n, f) \ 78 struct dwork_struct n = __DELAYED_WORK_INITIALIZER_NAR(n, f) 79 80 /* 81 * initialize a work item's function pointer 82 */ 83 #define PREPARE_WORK(_work, _func) \ 84 do { \ 85 (_work)->func = (_func); \ 86 } while (0) 87 88 #define PREPARE_DELAYED_WORK(_work, _func) \ 89 PREPARE_WORK(&(_work)->work, (_func)) 90 91 /* 92 * initialize all of a work item in one go 93 * 94 * NOTE! No point in using "atomic_long_set()": useing a direct 95 * assignment of the work data initializer allows the compiler 96 * to generate better code. 97 */ 98 #define INIT_WORK(_work, _func) \ 99 do { \ 100 (_work)->data = (atomic_long_t) WORK_DATA_INIT(0); \ 101 INIT_LIST_HEAD(&(_work)->entry); \ 102 PREPARE_WORK((_work), (_func)); \ 103 } while (0) 104 105 #define INIT_WORK_NAR(_work, _func) \ 106 do { \ 107 (_work)->data = (atomic_long_t) WORK_DATA_INIT(1); \ 108 INIT_LIST_HEAD(&(_work)->entry); \ 109 PREPARE_WORK((_work), (_func)); \ 110 } while (0) 111 112 #define INIT_DELAYED_WORK(_work, _func) \ 113 do { \ 114 INIT_WORK(&(_work)->work, (_func)); \ 115 init_timer(&(_work)->timer); \ 116 } while (0) 117 118 #define INIT_DELAYED_WORK_NAR(_work, _func) \ 119 do { \ 120 INIT_WORK_NAR(&(_work)->work, (_func)); \ 121 init_timer(&(_work)->timer); \ 122 } while (0) 123 124 #define INIT_DELAYED_WORK_DEFERRABLE(_work, _func) \ 125 do { \ 126 INIT_WORK(&(_work)->work, (_func)); \ 127 init_timer_deferrable(&(_work)->timer); \ 128 } while (0) 129 130 /** 131 * work_pending - Find out whether a work item is currently pending 132 * @work: The work item in question 133 */ 134 #define work_pending(work) \ 135 test_bit(WORK_STRUCT_PENDING, work_data_bits(work)) 136 137 /** 138 * delayed_work_pending - Find out whether a delayable work item is currently 139 * pending 140 * @work: The work item in question 141 */ 142 #define delayed_work_pending(w) \ 143 work_pending(&(w)->work) 144 145 /** 146 * work_release - Release a work item under execution 147 * @work: The work item to release 148 * 149 * This is used to release a work item that has been initialised with automatic 150 * release mode disabled (WORK_STRUCT_NOAUTOREL is set). This gives the work 151 * function the opportunity to grab auxiliary data from the container of the 152 * work_struct before clearing the pending bit as the work_struct may be 153 * subject to deallocation the moment the pending bit is cleared. 154 * 155 * In such a case, this should be called in the work function after it has 156 * fetched any data it may require from the containter of the work_struct. 157 * After this function has been called, the work_struct may be scheduled for 158 * further execution or it may be deallocated unless other precautions are 159 * taken. 160 * 161 * This should also be used to release a delayed work item. 162 */ 163 #define work_release(work) \ 164 clear_bit(WORK_STRUCT_PENDING, work_data_bits(work)) 165 166 167 extern struct workqueue_struct *__create_workqueue(const char *name, 168 int singlethread, 169 int freezeable); 170 #define create_workqueue(name) __create_workqueue((name), 0, 0) 171 #define create_freezeable_workqueue(name) __create_workqueue((name), 0, 1) 172 #define create_singlethread_workqueue(name) __create_workqueue((name), 1, 0) 173 174 extern void destroy_workqueue(struct workqueue_struct *wq); 175 176 extern int FASTCALL(queue_work(struct workqueue_struct *wq, struct work_struct *work)); 177 extern int FASTCALL(queue_delayed_work(struct workqueue_struct *wq, struct delayed_work *work, unsigned long delay)); 178 extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq, 179 struct delayed_work *work, unsigned long delay); 180 extern void FASTCALL(flush_workqueue(struct workqueue_struct *wq)); 181 182 extern int FASTCALL(schedule_work(struct work_struct *work)); 183 extern int FASTCALL(run_scheduled_work(struct work_struct *work)); 184 extern int FASTCALL(schedule_delayed_work(struct delayed_work *work, unsigned long delay)); 185 186 extern int schedule_delayed_work_on(int cpu, struct delayed_work *work, unsigned long delay); 187 extern int schedule_on_each_cpu(work_func_t func); 188 extern void flush_scheduled_work(void); 189 extern int current_is_keventd(void); 190 extern int keventd_up(void); 191 192 extern void init_workqueues(void); 193 void cancel_rearming_delayed_work(struct delayed_work *work); 194 void cancel_rearming_delayed_workqueue(struct workqueue_struct *, 195 struct delayed_work *); 196 int execute_in_process_context(work_func_t fn, struct execute_work *); 197 198 /* 199 * Kill off a pending schedule_delayed_work(). Note that the work callback 200 * function may still be running on return from cancel_delayed_work(), unless 201 * it returns 1 and the work doesn't re-arm itself. Run flush_workqueue() or 202 * cancel_work_sync() to wait on it. 203 */ 204 static inline int cancel_delayed_work(struct delayed_work *work) 205 { 206 int ret; 207 208 ret = del_timer(&work->timer); 209 if (ret) 210 work_release(&work->work); 211 return ret; 212 } 213 214 #endif 215