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_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
90 unsigned short tk_timeouts; /* maj timeouts */
91 size_t tk_bytes_sent; /* total bytes sent */
92 unsigned long tk_start; /* RPC task init timestamp */
93 long tk_rtt; /* round-trip time (jiffies) */
94
95 #ifdef RPC_DEBUG
96 unsigned short tk_pid; /* debugging aid */
97 #endif
98 };
99 #define tk_auth tk_client->cl_auth
100 #define tk_xprt tk_client->cl_xprt
101
102 /* support walking a list of tasks on a wait queue */
103 #define task_for_each(task, pos, head) \
104 list_for_each(pos, head) \
105 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1)
106
107 #define task_for_first(task, head) \
108 if (!list_empty(head) && \
109 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1))
110
111 /* .. and walking list of all tasks */
112 #define alltask_for_each(task, pos, head) \
113 list_for_each(pos, head) \
114 if ((task=list_entry(pos, struct rpc_task, tk_task)),1)
115
116 typedef void (*rpc_action)(struct rpc_task *);
117
118 struct rpc_call_ops {
119 void (*rpc_call_prepare)(struct rpc_task *, void *);
120 void (*rpc_call_done)(struct rpc_task *, void *);
121 void (*rpc_release)(void *);
122 };
123
124
125 /*
126 * RPC task flags
127 */
128 #define RPC_TASK_ASYNC 0x0001 /* is an async task */
129 #define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */
130 #define RPC_TASK_CHILD 0x0008 /* is child of other task */
131 #define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */
132 #define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */
133 #define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */
134 #define RPC_TASK_KILLED 0x0100 /* task was killed */
135 #define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */
136 #define RPC_TASK_NOINTR 0x0400 /* uninterruptible task */
137
138 #define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC)
139 #define RPC_IS_CHILD(t) ((t)->tk_flags & RPC_TASK_CHILD)
140 #define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER)
141 #define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS)
142 #define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED)
143 #define RPC_DO_CALLBACK(t) ((t)->tk_callback != NULL)
144 #define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT)
145 #define RPC_TASK_UNINTERRUPTIBLE(t) ((t)->tk_flags & RPC_TASK_NOINTR)
146
147 #define RPC_TASK_RUNNING 0
148 #define RPC_TASK_QUEUED 1
149 #define RPC_TASK_WAKEUP 2
150 #define RPC_TASK_HAS_TIMER 3
151 #define RPC_TASK_ACTIVE 4
152
153 #define RPC_IS_RUNNING(t) (test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate))
154 #define rpc_set_running(t) (set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate))
155 #define rpc_test_and_set_running(t) \
156 (test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate))
157 #define rpc_clear_running(t) \
158 do { \
159 smp_mb__before_clear_bit(); \
160 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
161 smp_mb__after_clear_bit(); \
162 } while (0)
163
164 #define RPC_IS_QUEUED(t) (test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate))
165 #define rpc_set_queued(t) (set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate))
166 #define rpc_clear_queued(t) \
167 do { \
168 smp_mb__before_clear_bit(); \
169 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
170 smp_mb__after_clear_bit(); \
171 } while (0)
172
173 #define rpc_start_wakeup(t) \
174 (test_and_set_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate) == 0)
175 #define rpc_finish_wakeup(t) \
176 do { \
177 smp_mb__before_clear_bit(); \
178 clear_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate); \
179 smp_mb__after_clear_bit(); \
180 } while (0)
181
182 #define RPC_IS_ACTIVATED(t) (test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate))
183 #define rpc_set_active(t) (set_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate))
184 #define rpc_clear_active(t) \
185 do { \
186 smp_mb__before_clear_bit(); \
187 clear_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate); \
188 smp_mb__after_clear_bit(); \
189 } while(0)
190
191 /*
192 * Task priorities.
193 * Note: if you change these, you must also change
194 * the task initialization definitions below.
195 */
196 #define RPC_PRIORITY_LOW 0
197 #define RPC_PRIORITY_NORMAL 1
198 #define RPC_PRIORITY_HIGH 2
199 #define RPC_NR_PRIORITY (RPC_PRIORITY_HIGH+1)
200
201 /*
202 * RPC synchronization objects
203 */
204 struct rpc_wait_queue {
205 spinlock_t lock;
206 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
207 unsigned long cookie; /* cookie of last task serviced */
208 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */
209 unsigned char priority; /* current priority */
210 unsigned char count; /* # task groups remaining serviced so far */
211 unsigned char nr; /* # tasks remaining for cookie */
212 unsigned short qlen; /* total # tasks waiting in queue */
213 #ifdef RPC_DEBUG
214 const char * name;
215 #endif
216 };
217
218 /*
219 * This is the # requests to send consecutively
220 * from a single cookie. The aim is to improve
221 * performance of NFS operations such as read/write.
222 */
223 #define RPC_BATCH_COUNT 16
224
225 #ifndef RPC_DEBUG
226 # define RPC_WAITQ_INIT(var,qname) { \
227 .lock = SPIN_LOCK_UNLOCKED, \
228 .tasks = { \
229 [0] = LIST_HEAD_INIT(var.tasks[0]), \
230 [1] = LIST_HEAD_INIT(var.tasks[1]), \
231 [2] = LIST_HEAD_INIT(var.tasks[2]), \
232 }, \
233 }
234 #else
235 # define RPC_WAITQ_INIT(var,qname) { \
236 .lock = SPIN_LOCK_UNLOCKED, \
237 .tasks = { \
238 [0] = LIST_HEAD_INIT(var.tasks[0]), \
239 [1] = LIST_HEAD_INIT(var.tasks[1]), \
240 [2] = LIST_HEAD_INIT(var.tasks[2]), \
241 }, \
242 .name = qname, \
243 }
244 #endif
245 # define RPC_WAITQ(var,qname) struct rpc_wait_queue var = RPC_WAITQ_INIT(var,qname)
246
247 #define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
248
249 /*
250 * Function prototypes
251 */
252 struct rpc_task *rpc_new_task(struct rpc_clnt *, int flags,
253 const struct rpc_call_ops *ops, void *data);
254 struct rpc_task *rpc_run_task(struct rpc_clnt *clnt, int flags,
255 const struct rpc_call_ops *ops, void *data);
256 struct rpc_task *rpc_new_child(struct rpc_clnt *, struct rpc_task *parent);
257 void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt,
258 int flags, const struct rpc_call_ops *ops,
259 void *data);
260 void rpc_release_task(struct rpc_task *);
261 void rpc_exit_task(struct rpc_task *);
262 void rpc_killall_tasks(struct rpc_clnt *);
263 int rpc_execute(struct rpc_task *);
264 void rpc_run_child(struct rpc_task *parent, struct rpc_task *child,
265 rpc_action action);
266 void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
267 void rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
268 void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
269 rpc_action action, rpc_action timer);
270 void rpc_wake_up_task(struct rpc_task *);
271 void rpc_wake_up(struct rpc_wait_queue *);
272 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
273 void rpc_wake_up_status(struct rpc_wait_queue *, int);
274 void rpc_delay(struct rpc_task *, unsigned long);
275 void * rpc_malloc(struct rpc_task *, size_t);
276 void rpc_free(struct rpc_task *);
277 int rpciod_up(void);
278 void rpciod_down(void);
279 int __rpc_wait_for_completion_task(struct rpc_task *task, int (*)(void *));
280 #ifdef RPC_DEBUG
281 void rpc_show_tasks(void);
282 #endif
283 int rpc_init_mempool(void);
284 void rpc_destroy_mempool(void);
285 extern struct workqueue_struct *rpciod_workqueue;
286
rpc_exit(struct rpc_task * task,int status)287 static inline void rpc_exit(struct rpc_task *task, int status)
288 {
289 task->tk_status = status;
290 task->tk_action = rpc_exit_task;
291 }
292
rpc_wait_for_completion_task(struct rpc_task * task)293 static inline int rpc_wait_for_completion_task(struct rpc_task *task)
294 {
295 return __rpc_wait_for_completion_task(task, NULL);
296 }
297
298 #ifdef RPC_DEBUG
rpc_qname(struct rpc_wait_queue * q)299 static inline const char * rpc_qname(struct rpc_wait_queue *q)
300 {
301 return ((q && q->name) ? q->name : "unknown");
302 }
303 #endif
304
305 #endif /* _LINUX_SUNRPC_SCHED_H_ */
306