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/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 tk_rebind_retry : 2;
89 };
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_count_stats)(struct rpc_task *, void *);
106 void (*rpc_release)(void *);
107 };
108
109 struct rpc_task_setup {
110 struct rpc_task *task;
111 struct rpc_clnt *rpc_client;
112 const struct rpc_message *rpc_message;
113 const struct rpc_call_ops *callback_ops;
114 void *callback_data;
115 struct workqueue_struct *workqueue;
116 unsigned short flags;
117 signed char priority;
118 };
119
120 /*
121 * RPC task flags
122 */
123 #define RPC_TASK_ASYNC 0x0001 /* is an async task */
124 #define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */
125 #define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */
126 #define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */
127 #define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */
128 #define RPC_TASK_KILLED 0x0100 /* task was killed */
129 #define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */
130 #define RPC_TASK_SOFTCONN 0x0400 /* Fail if can't connect */
131 #define RPC_TASK_SENT 0x0800 /* message was sent */
132 #define RPC_TASK_TIMEOUT 0x1000 /* fail with ETIMEDOUT on timeout */
133
134 #define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC)
135 #define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER)
136 #define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS)
137 #define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED)
138 #define RPC_IS_SOFT(t) ((t)->tk_flags & (RPC_TASK_SOFT|RPC_TASK_TIMEOUT))
139 #define RPC_IS_SOFTCONN(t) ((t)->tk_flags & RPC_TASK_SOFTCONN)
140 #define RPC_WAS_SENT(t) ((t)->tk_flags & RPC_TASK_SENT)
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 nr; /* # tasks remaining for cookie */
195 unsigned short qlen; /* total # tasks waiting in queue */
196 struct rpc_timer timer_list;
197 #if defined(RPC_DEBUG) || defined(RPC_TRACEPOINTS)
198 const char * name;
199 #endif
200 };
201
202 /*
203 * This is the # requests to send consecutively
204 * from a single cookie. The aim is to improve
205 * performance of NFS operations such as read/write.
206 */
207 #define RPC_BATCH_COUNT 16
208 #define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
209
210 /*
211 * Function prototypes
212 */
213 struct rpc_task *rpc_new_task(const struct rpc_task_setup *);
214 struct rpc_task *rpc_run_task(const struct rpc_task_setup *);
215 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
216 const struct rpc_call_ops *ops);
217 void rpc_put_task(struct rpc_task *);
218 void rpc_put_task_async(struct rpc_task *);
219 void rpc_exit_task(struct rpc_task *);
220 void rpc_exit(struct rpc_task *, int);
221 void rpc_release_calldata(const struct rpc_call_ops *, void *);
222 void rpc_killall_tasks(struct rpc_clnt *);
223 void rpc_execute(struct rpc_task *);
224 void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
225 void rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
226 void rpc_destroy_wait_queue(struct rpc_wait_queue *);
227 void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
228 rpc_action action);
229 void rpc_sleep_on_priority(struct rpc_wait_queue *,
230 struct rpc_task *,
231 rpc_action action,
232 int priority);
233 void rpc_wake_up_queued_task(struct rpc_wait_queue *,
234 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 struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *,
238 bool (*)(struct rpc_task *, void *),
239 void *);
240 void rpc_wake_up_status(struct rpc_wait_queue *, int);
241 int rpc_queue_empty(struct rpc_wait_queue *);
242 void rpc_delay(struct rpc_task *, unsigned long);
243 void * rpc_malloc(struct rpc_task *, size_t);
244 void rpc_free(void *);
245 int rpciod_up(void);
246 void rpciod_down(void);
247 int __rpc_wait_for_completion_task(struct rpc_task *task, int (*)(void *));
248 #ifdef RPC_DEBUG
249 struct net;
250 void rpc_show_tasks(struct net *);
251 #endif
252 int rpc_init_mempool(void);
253 void rpc_destroy_mempool(void);
254 extern struct workqueue_struct *rpciod_workqueue;
255 void rpc_prepare_task(struct rpc_task *task);
256
rpc_wait_for_completion_task(struct rpc_task * task)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
rpc_task_set_priority(struct rpc_task * task,unsigned char prio)262 static inline void rpc_task_set_priority(struct rpc_task *task, unsigned char prio)
263 {
264 task->tk_priority = prio - RPC_PRIORITY_LOW;
265 }
266
rpc_task_has_priority(struct rpc_task * task,unsigned char prio)267 static inline int rpc_task_has_priority(struct rpc_task *task, unsigned char prio)
268 {
269 return (task->tk_priority + RPC_PRIORITY_LOW == prio);
270 }
271
272 #if defined(RPC_DEBUG) || defined (RPC_TRACEPOINTS)
rpc_qname(const struct rpc_wait_queue * q)273 static inline const char * rpc_qname(const struct rpc_wait_queue *q)
274 {
275 return ((q && q->name) ? q->name : "unknown");
276 }
277
rpc_assign_waitqueue_name(struct rpc_wait_queue * q,const char * name)278 static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
279 const char *name)
280 {
281 q->name = name;
282 }
283 #else
rpc_assign_waitqueue_name(struct rpc_wait_queue * q,const char * name)284 static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
285 const char *name)
286 {
287 }
288 #endif
289
290 #endif /* _LINUX_SUNRPC_SCHED_H_ */
291