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/rcupdate.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 rpc_wait_queue * rpc_waitq; /* RPC wait queue we're on */ 37 }; 38 39 /* 40 * This is the RPC task struct 41 */ 42 struct rpc_task { 43 #ifdef RPC_DEBUG 44 unsigned long tk_magic; /* 0xf00baa */ 45 #endif 46 atomic_t tk_count; /* Reference count */ 47 struct list_head tk_task; /* global list of tasks */ 48 struct rpc_clnt * tk_client; /* RPC client */ 49 struct rpc_rqst * tk_rqstp; /* RPC request */ 50 int tk_status; /* result of last operation */ 51 52 /* 53 * RPC call state 54 */ 55 struct rpc_message tk_msg; /* RPC call info */ 56 __u8 tk_garb_retry; 57 __u8 tk_cred_retry; 58 59 /* 60 * timeout_fn to be executed by timer bottom half 61 * callback to be executed after waking up 62 * action next procedure for async tasks 63 * tk_ops caller callbacks 64 */ 65 void (*tk_timeout_fn)(struct rpc_task *); 66 void (*tk_callback)(struct rpc_task *); 67 void (*tk_action)(struct rpc_task *); 68 const struct rpc_call_ops *tk_ops; 69 void * tk_calldata; 70 71 /* 72 * tk_timer is used for async processing by the RPC scheduling 73 * primitives. You should not access this directly unless 74 * you have a pathological interest in kernel oopses. 75 */ 76 struct timer_list tk_timer; /* kernel timer */ 77 unsigned long tk_timeout; /* timeout for rpc_sleep() */ 78 unsigned short tk_flags; /* misc flags */ 79 unsigned long tk_runstate; /* Task run status */ 80 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could 81 * be any workqueue 82 */ 83 union { 84 struct work_struct tk_work; /* Async task work queue */ 85 struct rpc_wait tk_wait; /* RPC wait */ 86 struct rcu_head tk_rcu; /* for task deletion */ 87 } u; 88 89 unsigned short tk_timeouts; /* maj timeouts */ 90 size_t tk_bytes_sent; /* total bytes sent */ 91 unsigned long tk_start; /* RPC task init timestamp */ 92 long tk_rtt; /* round-trip time (jiffies) */ 93 94 pid_t tk_owner; /* Process id for batching tasks */ 95 unsigned char tk_priority : 2;/* Task priority */ 96 97 #ifdef RPC_DEBUG 98 unsigned short tk_pid; /* debugging aid */ 99 #endif 100 }; 101 #define tk_xprt tk_client->cl_xprt 102 103 /* support walking a list of tasks on a wait queue */ 104 #define task_for_each(task, pos, head) \ 105 list_for_each(pos, head) \ 106 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1) 107 108 #define task_for_first(task, head) \ 109 if (!list_empty(head) && \ 110 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1)) 111 112 typedef void (*rpc_action)(struct rpc_task *); 113 114 struct rpc_call_ops { 115 void (*rpc_call_prepare)(struct rpc_task *, void *); 116 void (*rpc_call_done)(struct rpc_task *, void *); 117 void (*rpc_release)(void *); 118 }; 119 120 struct rpc_task_setup { 121 struct rpc_task *task; 122 struct rpc_clnt *rpc_client; 123 const struct rpc_message *rpc_message; 124 const struct rpc_call_ops *callback_ops; 125 void *callback_data; 126 unsigned short flags; 127 signed char priority; 128 }; 129 130 /* 131 * RPC task flags 132 */ 133 #define RPC_TASK_ASYNC 0x0001 /* is an async task */ 134 #define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */ 135 #define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */ 136 #define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */ 137 #define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */ 138 #define RPC_TASK_KILLED 0x0100 /* task was killed */ 139 #define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */ 140 141 #define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC) 142 #define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER) 143 #define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS) 144 #define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED) 145 #define RPC_DO_CALLBACK(t) ((t)->tk_callback != NULL) 146 #define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT) 147 148 #define RPC_TASK_RUNNING 0 149 #define RPC_TASK_QUEUED 1 150 #define RPC_TASK_WAKEUP 2 151 #define RPC_TASK_HAS_TIMER 3 152 #define RPC_TASK_ACTIVE 4 153 154 #define RPC_IS_RUNNING(t) test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) 155 #define rpc_set_running(t) set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) 156 #define rpc_test_and_set_running(t) \ 157 test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) 158 #define rpc_clear_running(t) \ 159 do { \ 160 smp_mb__before_clear_bit(); \ 161 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \ 162 smp_mb__after_clear_bit(); \ 163 } while (0) 164 165 #define RPC_IS_QUEUED(t) test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate) 166 #define rpc_set_queued(t) set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate) 167 #define rpc_clear_queued(t) \ 168 do { \ 169 smp_mb__before_clear_bit(); \ 170 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \ 171 smp_mb__after_clear_bit(); \ 172 } while (0) 173 174 #define rpc_start_wakeup(t) \ 175 (test_and_set_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate) == 0) 176 #define rpc_finish_wakeup(t) \ 177 do { \ 178 smp_mb__before_clear_bit(); \ 179 clear_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate); \ 180 smp_mb__after_clear_bit(); \ 181 } while (0) 182 183 #define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate) 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 (-1) 191 #define RPC_PRIORITY_NORMAL (0) 192 #define RPC_PRIORITY_HIGH (1) 193 #define RPC_NR_PRIORITY (1 + RPC_PRIORITY_HIGH - RPC_PRIORITY_LOW) 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 pid_t owner; /* process id 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 unsigned short qlen; /* total # tasks waiting in queue */ 207 #ifdef RPC_DEBUG 208 const char * name; 209 #endif 210 }; 211 212 /* 213 * This is the # requests to send consecutively 214 * from a single cookie. The aim is to improve 215 * performance of NFS operations such as read/write. 216 */ 217 #define RPC_BATCH_COUNT 16 218 #define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0) 219 220 /* 221 * Function prototypes 222 */ 223 struct rpc_task *rpc_new_task(const struct rpc_task_setup *); 224 struct rpc_task *rpc_run_task(const struct rpc_task_setup *); 225 void rpc_put_task(struct rpc_task *); 226 void rpc_exit_task(struct rpc_task *); 227 void rpc_release_calldata(const struct rpc_call_ops *, void *); 228 void rpc_killall_tasks(struct rpc_clnt *); 229 void rpc_execute(struct rpc_task *); 230 void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *); 231 void rpc_init_wait_queue(struct rpc_wait_queue *, const char *); 232 void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *, 233 rpc_action action, rpc_action timer); 234 void rpc_wake_up_task(struct rpc_task *); 235 void rpc_wake_up(struct rpc_wait_queue *); 236 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *); 237 void rpc_wake_up_status(struct rpc_wait_queue *, int); 238 void rpc_delay(struct rpc_task *, unsigned long); 239 void * rpc_malloc(struct rpc_task *, size_t); 240 void rpc_free(void *); 241 int rpciod_up(void); 242 void rpciod_down(void); 243 int __rpc_wait_for_completion_task(struct rpc_task *task, int (*)(void *)); 244 #ifdef RPC_DEBUG 245 void rpc_show_tasks(void); 246 #endif 247 int rpc_init_mempool(void); 248 void rpc_destroy_mempool(void); 249 extern struct workqueue_struct *rpciod_workqueue; 250 251 static inline void rpc_exit(struct rpc_task *task, int status) 252 { 253 task->tk_status = status; 254 task->tk_action = rpc_exit_task; 255 } 256 257 static inline int rpc_wait_for_completion_task(struct rpc_task *task) 258 { 259 return __rpc_wait_for_completion_task(task, NULL); 260 } 261 262 #ifdef RPC_DEBUG 263 static inline const char * rpc_qname(struct rpc_wait_queue *q) 264 { 265 return ((q && q->name) ? q->name : "unknown"); 266 } 267 #endif 268 269 #endif /* _LINUX_SUNRPC_SCHED_H_ */ 270