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 list_head timer_list; /* Timer list */ 36 unsigned long expires; 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 * callback to be executed after waking up 61 * action next procedure for async tasks 62 * tk_ops caller callbacks 63 */ 64 void (*tk_callback)(struct rpc_task *); 65 void (*tk_action)(struct rpc_task *); 66 const struct rpc_call_ops *tk_ops; 67 void * tk_calldata; 68 69 unsigned long tk_timeout; /* timeout for rpc_sleep() */ 70 unsigned short tk_flags; /* misc flags */ 71 unsigned long tk_runstate; /* Task run status */ 72 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could 73 * be any workqueue 74 */ 75 struct rpc_wait_queue *tk_waitqueue; /* RPC wait queue we're on */ 76 union { 77 struct work_struct tk_work; /* Async task work queue */ 78 struct rpc_wait tk_wait; /* RPC wait */ 79 } u; 80 81 unsigned short tk_timeouts; /* maj timeouts */ 82 size_t tk_bytes_sent; /* total bytes sent */ 83 unsigned long tk_start; /* RPC task init timestamp */ 84 long tk_rtt; /* round-trip time (jiffies) */ 85 86 pid_t tk_owner; /* Process id for batching tasks */ 87 unsigned char tk_priority : 2;/* Task priority */ 88 89 #ifdef RPC_DEBUG 90 unsigned short tk_pid; /* debugging aid */ 91 #endif 92 }; 93 #define tk_xprt tk_client->cl_xprt 94 95 /* support walking a list of tasks on a wait queue */ 96 #define task_for_each(task, pos, head) \ 97 list_for_each(pos, head) \ 98 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1) 99 100 #define task_for_first(task, head) \ 101 if (!list_empty(head) && \ 102 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1)) 103 104 typedef void (*rpc_action)(struct rpc_task *); 105 106 struct rpc_call_ops { 107 void (*rpc_call_prepare)(struct rpc_task *, void *); 108 void (*rpc_call_done)(struct rpc_task *, void *); 109 void (*rpc_release)(void *); 110 }; 111 112 struct rpc_task_setup { 113 struct rpc_task *task; 114 struct rpc_clnt *rpc_client; 115 const struct rpc_message *rpc_message; 116 const struct rpc_call_ops *callback_ops; 117 void *callback_data; 118 struct workqueue_struct *workqueue; 119 unsigned short flags; 120 signed char priority; 121 }; 122 123 /* 124 * RPC task flags 125 */ 126 #define RPC_TASK_ASYNC 0x0001 /* is an async task */ 127 #define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */ 128 #define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */ 129 #define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */ 130 #define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */ 131 #define RPC_TASK_KILLED 0x0100 /* task was killed */ 132 #define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */ 133 #define RPC_TASK_SOFTCONN 0x0400 /* Fail if can't connect */ 134 135 #define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC) 136 #define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER) 137 #define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS) 138 #define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED) 139 #define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT) 140 #define RPC_IS_SOFTCONN(t) ((t)->tk_flags & RPC_TASK_SOFTCONN) 141 142 #define RPC_TASK_RUNNING 0 143 #define RPC_TASK_QUEUED 1 144 #define RPC_TASK_ACTIVE 2 145 146 #define RPC_IS_RUNNING(t) test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) 147 #define rpc_set_running(t) set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) 148 #define rpc_test_and_set_running(t) \ 149 test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) 150 #define rpc_clear_running(t) \ 151 do { \ 152 smp_mb__before_clear_bit(); \ 153 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \ 154 smp_mb__after_clear_bit(); \ 155 } while (0) 156 157 #define RPC_IS_QUEUED(t) test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate) 158 #define rpc_set_queued(t) set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate) 159 #define rpc_clear_queued(t) \ 160 do { \ 161 smp_mb__before_clear_bit(); \ 162 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \ 163 smp_mb__after_clear_bit(); \ 164 } while (0) 165 166 #define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate) 167 168 /* 169 * Task priorities. 170 * Note: if you change these, you must also change 171 * the task initialization definitions below. 172 */ 173 #define RPC_PRIORITY_LOW (-1) 174 #define RPC_PRIORITY_NORMAL (0) 175 #define RPC_PRIORITY_HIGH (1) 176 #define RPC_PRIORITY_PRIVILEGED (2) 177 #define RPC_NR_PRIORITY (1 + RPC_PRIORITY_PRIVILEGED - RPC_PRIORITY_LOW) 178 179 struct rpc_timer { 180 struct timer_list timer; 181 struct list_head list; 182 unsigned long expires; 183 }; 184 185 /* 186 * RPC synchronization objects 187 */ 188 struct rpc_wait_queue { 189 spinlock_t lock; 190 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */ 191 pid_t owner; /* process id of last task serviced */ 192 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */ 193 unsigned char priority; /* current priority */ 194 unsigned char count; /* # task groups remaining serviced so far */ 195 unsigned char nr; /* # tasks remaining for cookie */ 196 unsigned short qlen; /* total # tasks waiting in queue */ 197 struct rpc_timer timer_list; 198 #ifdef RPC_DEBUG 199 const char * name; 200 #endif 201 }; 202 203 /* 204 * This is the # requests to send consecutively 205 * from a single cookie. The aim is to improve 206 * performance of NFS operations such as read/write. 207 */ 208 #define RPC_BATCH_COUNT 16 209 #define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0) 210 211 /* 212 * Function prototypes 213 */ 214 struct rpc_task *rpc_new_task(const struct rpc_task_setup *); 215 struct rpc_task *rpc_run_task(const struct rpc_task_setup *); 216 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req, 217 const struct rpc_call_ops *ops); 218 void rpc_put_task(struct rpc_task *); 219 void rpc_exit_task(struct rpc_task *); 220 void rpc_release_calldata(const struct rpc_call_ops *, void *); 221 void rpc_killall_tasks(struct rpc_clnt *); 222 void rpc_execute(struct rpc_task *); 223 void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *); 224 void rpc_init_wait_queue(struct rpc_wait_queue *, const char *); 225 void rpc_destroy_wait_queue(struct rpc_wait_queue *); 226 void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *, 227 rpc_action action); 228 void rpc_wake_up_queued_task(struct rpc_wait_queue *, 229 struct rpc_task *); 230 void rpc_wake_up(struct rpc_wait_queue *); 231 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *); 232 void rpc_wake_up_status(struct rpc_wait_queue *, int); 233 int rpc_queue_empty(struct rpc_wait_queue *); 234 void rpc_delay(struct rpc_task *, unsigned long); 235 void * rpc_malloc(struct rpc_task *, size_t); 236 void rpc_free(void *); 237 int rpciod_up(void); 238 void rpciod_down(void); 239 int __rpc_wait_for_completion_task(struct rpc_task *task, int (*)(void *)); 240 #ifdef RPC_DEBUG 241 void rpc_show_tasks(void); 242 #endif 243 int rpc_init_mempool(void); 244 void rpc_destroy_mempool(void); 245 extern struct workqueue_struct *rpciod_workqueue; 246 void rpc_prepare_task(struct rpc_task *task); 247 248 static inline void rpc_exit(struct rpc_task *task, int status) 249 { 250 task->tk_status = status; 251 task->tk_action = rpc_exit_task; 252 } 253 254 static inline int rpc_wait_for_completion_task(struct rpc_task *task) 255 { 256 return __rpc_wait_for_completion_task(task, NULL); 257 } 258 259 static inline void rpc_task_set_priority(struct rpc_task *task, unsigned char prio) 260 { 261 task->tk_priority = prio - RPC_PRIORITY_LOW; 262 } 263 264 static inline int rpc_task_has_priority(struct rpc_task *task, unsigned char prio) 265 { 266 return (task->tk_priority + RPC_PRIORITY_LOW == prio); 267 } 268 269 #ifdef RPC_DEBUG 270 static inline const char * rpc_qname(struct rpc_wait_queue *q) 271 { 272 return ((q && q->name) ? q->name : "unknown"); 273 } 274 #endif 275 276 #endif /* _LINUX_SUNRPC_SCHED_H_ */ 277