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/ktime.h> 14 #include <linux/sunrpc/types.h> 15 #include <linux/spinlock.h> 16 #include <linux/wait.h> 17 #include <linux/workqueue.h> 18 #include <linux/sunrpc/xdr.h> 19 20 /* 21 * This is the actual RPC procedure call info. 22 */ 23 struct rpc_procinfo; 24 struct rpc_message { 25 struct rpc_procinfo * rpc_proc; /* Procedure information */ 26 void * rpc_argp; /* Arguments */ 27 void * rpc_resp; /* Result */ 28 struct rpc_cred * rpc_cred; /* Credentials */ 29 }; 30 31 struct rpc_call_ops; 32 struct rpc_wait_queue; 33 struct rpc_wait { 34 struct list_head list; /* wait queue links */ 35 struct list_head links; /* Links to related tasks */ 36 struct list_head timer_list; /* Timer list */ 37 unsigned long expires; 38 }; 39 40 /* 41 * This is the RPC task struct 42 */ 43 struct rpc_task { 44 atomic_t tk_count; /* Reference count */ 45 struct list_head tk_task; /* global list of tasks */ 46 struct rpc_clnt * tk_client; /* RPC client */ 47 struct rpc_rqst * tk_rqstp; /* RPC request */ 48 49 /* 50 * RPC call state 51 */ 52 struct rpc_message tk_msg; /* RPC call info */ 53 54 /* 55 * callback to be executed after waking up 56 * action next procedure for async tasks 57 * tk_ops caller callbacks 58 */ 59 void (*tk_callback)(struct rpc_task *); 60 void (*tk_action)(struct rpc_task *); 61 const struct rpc_call_ops *tk_ops; 62 void * tk_calldata; 63 64 unsigned long tk_timeout; /* timeout for rpc_sleep() */ 65 unsigned long tk_runstate; /* Task run status */ 66 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could 67 * be any workqueue 68 */ 69 struct rpc_wait_queue *tk_waitqueue; /* RPC wait queue we're on */ 70 union { 71 struct work_struct tk_work; /* Async task work queue */ 72 struct rpc_wait tk_wait; /* RPC wait */ 73 } u; 74 75 ktime_t tk_start; /* RPC task init timestamp */ 76 77 pid_t tk_owner; /* Process id for batching tasks */ 78 int tk_status; /* result of last operation */ 79 unsigned short tk_flags; /* misc flags */ 80 unsigned short tk_timeouts; /* maj timeouts */ 81 82 #ifdef RPC_DEBUG 83 unsigned short tk_pid; /* debugging aid */ 84 #endif 85 unsigned char tk_priority : 2,/* Task priority */ 86 tk_garb_retry : 2, 87 tk_cred_retry : 2; 88 }; 89 #define tk_xprt tk_client->cl_xprt 90 91 /* support walking a list of tasks on a wait queue */ 92 #define task_for_each(task, pos, head) \ 93 list_for_each(pos, head) \ 94 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1) 95 96 #define task_for_first(task, head) \ 97 if (!list_empty(head) && \ 98 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1)) 99 100 typedef void (*rpc_action)(struct rpc_task *); 101 102 struct rpc_call_ops { 103 void (*rpc_call_prepare)(struct rpc_task *, void *); 104 void (*rpc_call_done)(struct rpc_task *, void *); 105 void (*rpc_release)(void *); 106 }; 107 108 struct rpc_task_setup { 109 struct rpc_task *task; 110 struct rpc_clnt *rpc_client; 111 const struct rpc_message *rpc_message; 112 const struct rpc_call_ops *callback_ops; 113 void *callback_data; 114 struct workqueue_struct *workqueue; 115 unsigned short flags; 116 signed char priority; 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_CALL_MAJORSEEN 0x0020 /* major timeout seen */ 125 #define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */ 126 #define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */ 127 #define RPC_TASK_KILLED 0x0100 /* task was killed */ 128 #define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */ 129 #define RPC_TASK_SOFTCONN 0x0400 /* Fail if can't connect */ 130 131 #define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC) 132 #define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER) 133 #define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS) 134 #define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED) 135 #define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT) 136 #define RPC_IS_SOFTCONN(t) ((t)->tk_flags & RPC_TASK_SOFTCONN) 137 138 #define RPC_TASK_RUNNING 0 139 #define RPC_TASK_QUEUED 1 140 #define RPC_TASK_ACTIVE 2 141 142 #define RPC_IS_RUNNING(t) test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) 143 #define rpc_set_running(t) set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) 144 #define rpc_test_and_set_running(t) \ 145 test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) 146 #define rpc_clear_running(t) \ 147 do { \ 148 smp_mb__before_clear_bit(); \ 149 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \ 150 smp_mb__after_clear_bit(); \ 151 } while (0) 152 153 #define RPC_IS_QUEUED(t) test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate) 154 #define rpc_set_queued(t) set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate) 155 #define rpc_clear_queued(t) \ 156 do { \ 157 smp_mb__before_clear_bit(); \ 158 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \ 159 smp_mb__after_clear_bit(); \ 160 } while (0) 161 162 #define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate) 163 164 /* 165 * Task priorities. 166 * Note: if you change these, you must also change 167 * the task initialization definitions below. 168 */ 169 #define RPC_PRIORITY_LOW (-1) 170 #define RPC_PRIORITY_NORMAL (0) 171 #define RPC_PRIORITY_HIGH (1) 172 #define RPC_PRIORITY_PRIVILEGED (2) 173 #define RPC_NR_PRIORITY (1 + RPC_PRIORITY_PRIVILEGED - RPC_PRIORITY_LOW) 174 175 struct rpc_timer { 176 struct timer_list timer; 177 struct list_head list; 178 unsigned long expires; 179 }; 180 181 /* 182 * RPC synchronization objects 183 */ 184 struct rpc_wait_queue { 185 spinlock_t lock; 186 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */ 187 pid_t owner; /* process id of last task serviced */ 188 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */ 189 unsigned char priority; /* current priority */ 190 unsigned char count; /* # task groups remaining serviced so far */ 191 unsigned char nr; /* # tasks remaining for cookie */ 192 unsigned short qlen; /* total # tasks waiting in queue */ 193 struct rpc_timer timer_list; 194 #ifdef RPC_DEBUG 195 const char * name; 196 #endif 197 }; 198 199 /* 200 * This is the # requests to send consecutively 201 * from a single cookie. The aim is to improve 202 * performance of NFS operations such as read/write. 203 */ 204 #define RPC_BATCH_COUNT 16 205 #define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0) 206 207 /* 208 * Function prototypes 209 */ 210 struct rpc_task *rpc_new_task(const struct rpc_task_setup *); 211 struct rpc_task *rpc_run_task(const struct rpc_task_setup *); 212 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req, 213 const struct rpc_call_ops *ops); 214 void rpc_put_task(struct rpc_task *); 215 void rpc_put_task_async(struct rpc_task *); 216 void rpc_exit_task(struct rpc_task *); 217 void rpc_exit(struct rpc_task *, int); 218 void rpc_release_calldata(const struct rpc_call_ops *, void *); 219 void rpc_killall_tasks(struct rpc_clnt *); 220 void rpc_execute(struct rpc_task *); 221 void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *); 222 void rpc_init_wait_queue(struct rpc_wait_queue *, const char *); 223 void rpc_destroy_wait_queue(struct rpc_wait_queue *); 224 void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *, 225 rpc_action action); 226 void rpc_wake_up_queued_task(struct rpc_wait_queue *, 227 struct rpc_task *); 228 void rpc_wake_up(struct rpc_wait_queue *); 229 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *); 230 void rpc_wake_up_status(struct rpc_wait_queue *, int); 231 int rpc_queue_empty(struct rpc_wait_queue *); 232 void rpc_delay(struct rpc_task *, unsigned long); 233 void * rpc_malloc(struct rpc_task *, size_t); 234 void rpc_free(void *); 235 int rpciod_up(void); 236 void rpciod_down(void); 237 int __rpc_wait_for_completion_task(struct rpc_task *task, int (*)(void *)); 238 #ifdef RPC_DEBUG 239 void rpc_show_tasks(void); 240 #endif 241 int rpc_init_mempool(void); 242 void rpc_destroy_mempool(void); 243 extern struct workqueue_struct *rpciod_workqueue; 244 void rpc_prepare_task(struct rpc_task *task); 245 246 static inline int rpc_wait_for_completion_task(struct rpc_task *task) 247 { 248 return __rpc_wait_for_completion_task(task, NULL); 249 } 250 251 static inline void rpc_task_set_priority(struct rpc_task *task, unsigned char prio) 252 { 253 task->tk_priority = prio - RPC_PRIORITY_LOW; 254 } 255 256 static inline int rpc_task_has_priority(struct rpc_task *task, unsigned char prio) 257 { 258 return (task->tk_priority + RPC_PRIORITY_LOW == prio); 259 } 260 261 #ifdef RPC_DEBUG 262 static inline const char * rpc_qname(struct rpc_wait_queue *q) 263 { 264 return ((q && q->name) ? q->name : "unknown"); 265 } 266 #endif 267 268 #endif /* _LINUX_SUNRPC_SCHED_H_ */ 269