1 /* 2 * linux/include/linux/sunrpc/sched.h 3 * 4 * Scheduling primitives for kernel Sun RPC. 5 * 6 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de> 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_wait_queue; 31 struct rpc_wait { 32 struct list_head list; /* wait queue links */ 33 struct list_head links; /* Links to related tasks */ 34 wait_queue_head_t waitq; /* sync: sleep on this q */ 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 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 int tk_status; /* result of last operation */ 49 50 /* 51 * RPC call state 52 */ 53 struct rpc_message tk_msg; /* RPC call info */ 54 __u32 * tk_buffer; /* XDR buffer */ 55 size_t tk_bufsize; 56 __u8 tk_garb_retry; 57 __u8 tk_cred_retry; 58 59 unsigned long tk_cookie; /* Cookie for batching tasks */ 60 61 /* 62 * timeout_fn to be executed by timer bottom half 63 * callback to be executed after waking up 64 * action next procedure for async tasks 65 * exit exit async task and report to caller 66 */ 67 void (*tk_timeout_fn)(struct rpc_task *); 68 void (*tk_callback)(struct rpc_task *); 69 void (*tk_action)(struct rpc_task *); 70 void (*tk_exit)(struct rpc_task *); 71 void (*tk_release)(struct rpc_task *); 72 void * tk_calldata; 73 74 /* 75 * tk_timer is used for async processing by the RPC scheduling 76 * primitives. You should not access this directly unless 77 * you have a pathological interest in kernel oopses. 78 */ 79 struct timer_list tk_timer; /* kernel timer */ 80 unsigned long tk_timeout; /* timeout for rpc_sleep() */ 81 unsigned short tk_flags; /* misc flags */ 82 unsigned char tk_active : 1;/* Task has been activated */ 83 unsigned char tk_priority : 2;/* Task priority */ 84 unsigned long tk_runstate; /* Task run status */ 85 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could 86 * be any workqueue 87 */ 88 union { 89 struct work_struct tk_work; /* Async task work queue */ 90 struct rpc_wait tk_wait; /* RPC wait */ 91 } u; 92 #ifdef RPC_DEBUG 93 unsigned short tk_pid; /* debugging aid */ 94 #endif 95 }; 96 #define tk_auth tk_client->cl_auth 97 #define tk_xprt tk_client->cl_xprt 98 99 /* support walking a list of tasks on a wait queue */ 100 #define task_for_each(task, pos, head) \ 101 list_for_each(pos, head) \ 102 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1) 103 104 #define task_for_first(task, head) \ 105 if (!list_empty(head) && \ 106 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1)) 107 108 /* .. and walking list of all tasks */ 109 #define alltask_for_each(task, pos, head) \ 110 list_for_each(pos, head) \ 111 if ((task=list_entry(pos, struct rpc_task, tk_task)),1) 112 113 typedef void (*rpc_action)(struct rpc_task *); 114 115 /* 116 * RPC task flags 117 */ 118 #define RPC_TASK_ASYNC 0x0001 /* is an async task */ 119 #define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */ 120 #define RPC_TASK_CHILD 0x0008 /* is child of other task */ 121 #define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */ 122 #define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */ 123 #define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */ 124 #define RPC_TASK_KILLED 0x0100 /* task was killed */ 125 #define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */ 126 #define RPC_TASK_NOINTR 0x0400 /* uninterruptible task */ 127 128 #define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC) 129 #define RPC_IS_CHILD(t) ((t)->tk_flags & RPC_TASK_CHILD) 130 #define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER) 131 #define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS) 132 #define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED) 133 #define RPC_IS_ACTIVATED(t) ((t)->tk_active) 134 #define RPC_DO_CALLBACK(t) ((t)->tk_callback != NULL) 135 #define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT) 136 #define RPC_TASK_UNINTERRUPTIBLE(t) ((t)->tk_flags & RPC_TASK_NOINTR) 137 138 #define RPC_TASK_RUNNING 0 139 #define RPC_TASK_QUEUED 1 140 #define RPC_TASK_WAKEUP 2 141 #define RPC_TASK_HAS_TIMER 3 142 143 #define RPC_IS_RUNNING(t) (test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)) 144 #define rpc_set_running(t) (set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)) 145 #define rpc_test_and_set_running(t) \ 146 (test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)) 147 #define rpc_clear_running(t) \ 148 do { \ 149 smp_mb__before_clear_bit(); \ 150 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \ 151 smp_mb__after_clear_bit(); \ 152 } while (0) 153 154 #define RPC_IS_QUEUED(t) (test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)) 155 #define rpc_set_queued(t) (set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)) 156 #define rpc_clear_queued(t) \ 157 do { \ 158 smp_mb__before_clear_bit(); \ 159 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \ 160 smp_mb__after_clear_bit(); \ 161 } while (0) 162 163 #define rpc_start_wakeup(t) \ 164 (test_and_set_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate) == 0) 165 #define rpc_finish_wakeup(t) \ 166 do { \ 167 smp_mb__before_clear_bit(); \ 168 clear_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate); \ 169 smp_mb__after_clear_bit(); \ 170 } while (0) 171 172 /* 173 * Task priorities. 174 * Note: if you change these, you must also change 175 * the task initialization definitions below. 176 */ 177 #define RPC_PRIORITY_LOW 0 178 #define RPC_PRIORITY_NORMAL 1 179 #define RPC_PRIORITY_HIGH 2 180 #define RPC_NR_PRIORITY (RPC_PRIORITY_HIGH+1) 181 182 /* 183 * RPC synchronization objects 184 */ 185 struct rpc_wait_queue { 186 spinlock_t lock; 187 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */ 188 unsigned long cookie; /* cookie of last task serviced */ 189 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */ 190 unsigned char priority; /* current priority */ 191 unsigned char count; /* # task groups remaining serviced so far */ 192 unsigned char nr; /* # tasks remaining for cookie */ 193 #ifdef RPC_DEBUG 194 const char * name; 195 #endif 196 }; 197 198 /* 199 * This is the # requests to send consecutively 200 * from a single cookie. The aim is to improve 201 * performance of NFS operations such as read/write. 202 */ 203 #define RPC_BATCH_COUNT 16 204 205 #ifndef RPC_DEBUG 206 # define RPC_WAITQ_INIT(var,qname) { \ 207 .lock = SPIN_LOCK_UNLOCKED, \ 208 .tasks = { \ 209 [0] = LIST_HEAD_INIT(var.tasks[0]), \ 210 [1] = LIST_HEAD_INIT(var.tasks[1]), \ 211 [2] = LIST_HEAD_INIT(var.tasks[2]), \ 212 }, \ 213 } 214 #else 215 # define RPC_WAITQ_INIT(var,qname) { \ 216 .lock = SPIN_LOCK_UNLOCKED, \ 217 .tasks = { \ 218 [0] = LIST_HEAD_INIT(var.tasks[0]), \ 219 [1] = LIST_HEAD_INIT(var.tasks[1]), \ 220 [2] = LIST_HEAD_INIT(var.tasks[2]), \ 221 }, \ 222 .name = qname, \ 223 } 224 #endif 225 # define RPC_WAITQ(var,qname) struct rpc_wait_queue var = RPC_WAITQ_INIT(var,qname) 226 227 #define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0) 228 229 /* 230 * Function prototypes 231 */ 232 struct rpc_task *rpc_new_task(struct rpc_clnt *, rpc_action, int flags); 233 struct rpc_task *rpc_new_child(struct rpc_clnt *, struct rpc_task *parent); 234 void rpc_init_task(struct rpc_task *, struct rpc_clnt *, 235 rpc_action exitfunc, int flags); 236 void rpc_release_task(struct rpc_task *); 237 void rpc_killall_tasks(struct rpc_clnt *); 238 int rpc_execute(struct rpc_task *); 239 void rpc_run_child(struct rpc_task *parent, struct rpc_task *child, 240 rpc_action action); 241 void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *); 242 void rpc_init_wait_queue(struct rpc_wait_queue *, const char *); 243 void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *, 244 rpc_action action, rpc_action timer); 245 void rpc_wake_up_task(struct rpc_task *); 246 void rpc_wake_up(struct rpc_wait_queue *); 247 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *); 248 void rpc_wake_up_status(struct rpc_wait_queue *, int); 249 void rpc_delay(struct rpc_task *, unsigned long); 250 void * rpc_malloc(struct rpc_task *, size_t); 251 int rpciod_up(void); 252 void rpciod_down(void); 253 void rpciod_wake_up(void); 254 #ifdef RPC_DEBUG 255 void rpc_show_tasks(void); 256 #endif 257 int rpc_init_mempool(void); 258 void rpc_destroy_mempool(void); 259 260 static inline void rpc_exit(struct rpc_task *task, int status) 261 { 262 task->tk_status = status; 263 task->tk_action = NULL; 264 } 265 266 #ifdef RPC_DEBUG 267 static inline const char * rpc_qname(struct rpc_wait_queue *q) 268 { 269 return ((q && q->name) ? q->name : "unknown"); 270 } 271 #endif 272 273 #endif /* _LINUX_SUNRPC_SCHED_H_ */ 274