1 /* 2 * linux/include/linux/sunrpc/sched.h 3 * 4 * Scheduling primitives for kernel Sun RPC. 5 * 6 * Copyright (C) 1996, Olaf Kirch <[email protected]> 7 */ 8 9 #ifndef _LINUX_SUNRPC_SCHED_H_ 10 #define _LINUX_SUNRPC_SCHED_H_ 11 12 #include <linux/timer.h> 13 #include <linux/sunrpc/types.h> 14 #include <linux/spinlock.h> 15 #include <linux/wait.h> 16 #include <linux/workqueue.h> 17 #include <linux/sunrpc/xdr.h> 18 19 /* 20 * This is the actual RPC procedure call info. 21 */ 22 struct rpc_procinfo; 23 struct rpc_message { 24 struct rpc_procinfo * rpc_proc; /* Procedure information */ 25 void * rpc_argp; /* Arguments */ 26 void * rpc_resp; /* Result */ 27 struct rpc_cred * rpc_cred; /* Credentials */ 28 }; 29 30 struct rpc_call_ops; 31 struct rpc_wait_queue; 32 struct rpc_wait { 33 struct list_head list; /* wait queue links */ 34 struct list_head links; /* Links to related tasks */ 35 struct rpc_wait_queue * rpc_waitq; /* RPC wait queue we're on */ 36 }; 37 38 /* 39 * This is the RPC task struct 40 */ 41 struct rpc_task { 42 #ifdef RPC_DEBUG 43 unsigned long tk_magic; /* 0xf00baa */ 44 #endif 45 atomic_t tk_count; /* Reference count */ 46 struct list_head tk_task; /* global list of tasks */ 47 struct rpc_clnt * tk_client; /* RPC client */ 48 struct rpc_rqst * tk_rqstp; /* RPC request */ 49 int tk_status; /* result of last operation */ 50 51 /* 52 * RPC call state 53 */ 54 struct rpc_message tk_msg; /* RPC call info */ 55 __u8 tk_garb_retry; 56 __u8 tk_cred_retry; 57 58 unsigned long tk_cookie; /* Cookie for batching tasks */ 59 60 /* 61 * timeout_fn to be executed by timer bottom half 62 * callback to be executed after waking up 63 * action next procedure for async tasks 64 * tk_ops caller callbacks 65 */ 66 void (*tk_timeout_fn)(struct rpc_task *); 67 void (*tk_callback)(struct rpc_task *); 68 void (*tk_action)(struct rpc_task *); 69 const struct rpc_call_ops *tk_ops; 70 void * tk_calldata; 71 72 /* 73 * tk_timer is used for async processing by the RPC scheduling 74 * primitives. You should not access this directly unless 75 * you have a pathological interest in kernel oopses. 76 */ 77 struct timer_list tk_timer; /* kernel timer */ 78 unsigned long tk_timeout; /* timeout for rpc_sleep() */ 79 unsigned short tk_flags; /* misc flags */ 80 unsigned char tk_priority : 2;/* Task priority */ 81 unsigned long tk_runstate; /* Task run status */ 82 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could 83 * be any workqueue 84 */ 85 union { 86 struct work_struct tk_work; /* Async task work queue */ 87 struct rpc_wait tk_wait; /* RPC wait */ 88 } u; 89 #ifdef RPC_DEBUG 90 unsigned short tk_pid; /* debugging aid */ 91 #endif 92 }; 93 #define tk_auth tk_client->cl_auth 94 #define tk_xprt tk_client->cl_xprt 95 96 /* support walking a list of tasks on a wait queue */ 97 #define task_for_each(task, pos, head) \ 98 list_for_each(pos, head) \ 99 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1) 100 101 #define task_for_first(task, head) \ 102 if (!list_empty(head) && \ 103 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1)) 104 105 /* .. and walking list of all tasks */ 106 #define alltask_for_each(task, pos, head) \ 107 list_for_each(pos, head) \ 108 if ((task=list_entry(pos, struct rpc_task, tk_task)),1) 109 110 typedef void (*rpc_action)(struct rpc_task *); 111 112 struct rpc_call_ops { 113 void (*rpc_call_prepare)(struct rpc_task *, void *); 114 void (*rpc_call_done)(struct rpc_task *, void *); 115 void (*rpc_release)(void *); 116 }; 117 118 119 /* 120 * RPC task flags 121 */ 122 #define RPC_TASK_ASYNC 0x0001 /* is an async task */ 123 #define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */ 124 #define RPC_TASK_CHILD 0x0008 /* is child of other task */ 125 #define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */ 126 #define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */ 127 #define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */ 128 #define RPC_TASK_KILLED 0x0100 /* task was killed */ 129 #define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */ 130 #define RPC_TASK_NOINTR 0x0400 /* uninterruptible task */ 131 132 #define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC) 133 #define RPC_IS_CHILD(t) ((t)->tk_flags & RPC_TASK_CHILD) 134 #define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER) 135 #define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS) 136 #define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED) 137 #define RPC_DO_CALLBACK(t) ((t)->tk_callback != NULL) 138 #define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT) 139 #define RPC_TASK_UNINTERRUPTIBLE(t) ((t)->tk_flags & RPC_TASK_NOINTR) 140 141 #define RPC_TASK_RUNNING 0 142 #define RPC_TASK_QUEUED 1 143 #define RPC_TASK_WAKEUP 2 144 #define RPC_TASK_HAS_TIMER 3 145 #define RPC_TASK_ACTIVE 4 146 147 #define RPC_IS_RUNNING(t) (test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)) 148 #define rpc_set_running(t) (set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)) 149 #define rpc_test_and_set_running(t) \ 150 (test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)) 151 #define rpc_clear_running(t) \ 152 do { \ 153 smp_mb__before_clear_bit(); \ 154 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \ 155 smp_mb__after_clear_bit(); \ 156 } while (0) 157 158 #define RPC_IS_QUEUED(t) (test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)) 159 #define rpc_set_queued(t) (set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)) 160 #define rpc_clear_queued(t) \ 161 do { \ 162 smp_mb__before_clear_bit(); \ 163 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \ 164 smp_mb__after_clear_bit(); \ 165 } while (0) 166 167 #define rpc_start_wakeup(t) \ 168 (test_and_set_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate) == 0) 169 #define rpc_finish_wakeup(t) \ 170 do { \ 171 smp_mb__before_clear_bit(); \ 172 clear_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate); \ 173 smp_mb__after_clear_bit(); \ 174 } while (0) 175 176 #define RPC_IS_ACTIVATED(t) (test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)) 177 #define rpc_set_active(t) (set_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)) 178 #define rpc_clear_active(t) \ 179 do { \ 180 smp_mb__before_clear_bit(); \ 181 clear_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate); \ 182 smp_mb__after_clear_bit(); \ 183 } while(0) 184 185 /* 186 * Task priorities. 187 * Note: if you change these, you must also change 188 * the task initialization definitions below. 189 */ 190 #define RPC_PRIORITY_LOW 0 191 #define RPC_PRIORITY_NORMAL 1 192 #define RPC_PRIORITY_HIGH 2 193 #define RPC_NR_PRIORITY (RPC_PRIORITY_HIGH+1) 194 195 /* 196 * RPC synchronization objects 197 */ 198 struct rpc_wait_queue { 199 spinlock_t lock; 200 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */ 201 unsigned long cookie; /* cookie of last task serviced */ 202 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */ 203 unsigned char priority; /* current priority */ 204 unsigned char count; /* # task groups remaining serviced so far */ 205 unsigned char nr; /* # tasks remaining for cookie */ 206 #ifdef RPC_DEBUG 207 const char * name; 208 #endif 209 }; 210 211 /* 212 * This is the # requests to send consecutively 213 * from a single cookie. The aim is to improve 214 * performance of NFS operations such as read/write. 215 */ 216 #define RPC_BATCH_COUNT 16 217 218 #ifndef RPC_DEBUG 219 # define RPC_WAITQ_INIT(var,qname) { \ 220 .lock = SPIN_LOCK_UNLOCKED, \ 221 .tasks = { \ 222 [0] = LIST_HEAD_INIT(var.tasks[0]), \ 223 [1] = LIST_HEAD_INIT(var.tasks[1]), \ 224 [2] = LIST_HEAD_INIT(var.tasks[2]), \ 225 }, \ 226 } 227 #else 228 # define RPC_WAITQ_INIT(var,qname) { \ 229 .lock = SPIN_LOCK_UNLOCKED, \ 230 .tasks = { \ 231 [0] = LIST_HEAD_INIT(var.tasks[0]), \ 232 [1] = LIST_HEAD_INIT(var.tasks[1]), \ 233 [2] = LIST_HEAD_INIT(var.tasks[2]), \ 234 }, \ 235 .name = qname, \ 236 } 237 #endif 238 # define RPC_WAITQ(var,qname) struct rpc_wait_queue var = RPC_WAITQ_INIT(var,qname) 239 240 #define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0) 241 242 /* 243 * Function prototypes 244 */ 245 struct rpc_task *rpc_new_task(struct rpc_clnt *, int flags, 246 const struct rpc_call_ops *ops, void *data); 247 struct rpc_task *rpc_run_task(struct rpc_clnt *clnt, int flags, 248 const struct rpc_call_ops *ops, void *data); 249 struct rpc_task *rpc_new_child(struct rpc_clnt *, struct rpc_task *parent); 250 void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt, 251 int flags, const struct rpc_call_ops *ops, 252 void *data); 253 void rpc_release_task(struct rpc_task *); 254 void rpc_exit_task(struct rpc_task *); 255 void rpc_killall_tasks(struct rpc_clnt *); 256 int rpc_execute(struct rpc_task *); 257 void rpc_run_child(struct rpc_task *parent, struct rpc_task *child, 258 rpc_action action); 259 void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *); 260 void rpc_init_wait_queue(struct rpc_wait_queue *, const char *); 261 void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *, 262 rpc_action action, rpc_action timer); 263 void rpc_wake_up_task(struct rpc_task *); 264 void rpc_wake_up(struct rpc_wait_queue *); 265 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *); 266 void rpc_wake_up_status(struct rpc_wait_queue *, int); 267 void rpc_delay(struct rpc_task *, unsigned long); 268 void * rpc_malloc(struct rpc_task *, size_t); 269 void rpc_free(struct rpc_task *); 270 int rpciod_up(void); 271 void rpciod_down(void); 272 void rpciod_wake_up(void); 273 int __rpc_wait_for_completion_task(struct rpc_task *task, int (*)(void *)); 274 #ifdef RPC_DEBUG 275 void rpc_show_tasks(void); 276 #endif 277 int rpc_init_mempool(void); 278 void rpc_destroy_mempool(void); 279 280 static inline void rpc_exit(struct rpc_task *task, int status) 281 { 282 task->tk_status = status; 283 task->tk_action = rpc_exit_task; 284 } 285 286 static inline int rpc_wait_for_completion_task(struct rpc_task *task) 287 { 288 return __rpc_wait_for_completion_task(task, NULL); 289 } 290 291 #ifdef RPC_DEBUG 292 static inline const char * rpc_qname(struct rpc_wait_queue *q) 293 { 294 return ((q && q->name) ? q->name : "unknown"); 295 } 296 #endif 297 298 #endif /* _LINUX_SUNRPC_SCHED_H_ */ 299