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 #define tk_xprt tk_client->cl_xprt
91
92 /* support walking a list of tasks on a wait queue */
93 #define task_for_each(task, pos, head) \
94 list_for_each(pos, head) \
95 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1)
96
97 #define task_for_first(task, head) \
98 if (!list_empty(head) && \
99 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1))
100
101 typedef void (*rpc_action)(struct rpc_task *);
102
103 struct rpc_call_ops {
104 void (*rpc_call_prepare)(struct rpc_task *, void *);
105 void (*rpc_call_done)(struct rpc_task *, void *);
106 void (*rpc_count_stats)(struct rpc_task *, void *);
107 void (*rpc_release)(void *);
108 };
109
110 struct rpc_task_setup {
111 struct rpc_task *task;
112 struct rpc_clnt *rpc_client;
113 const struct rpc_message *rpc_message;
114 const struct rpc_call_ops *callback_ops;
115 void *callback_data;
116 struct workqueue_struct *workqueue;
117 unsigned short flags;
118 signed char priority;
119 };
120
121 /*
122 * RPC task flags
123 */
124 #define RPC_TASK_ASYNC 0x0001 /* is an async task */
125 #define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */
126 #define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */
127 #define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */
128 #define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */
129 #define RPC_TASK_KILLED 0x0100 /* task was killed */
130 #define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */
131 #define RPC_TASK_SOFTCONN 0x0400 /* Fail if can't connect */
132 #define RPC_TASK_SENT 0x0800 /* message was sent */
133 #define RPC_TASK_TIMEOUT 0x1000 /* fail with ETIMEDOUT on timeout */
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|RPC_TASK_TIMEOUT))
140 #define RPC_IS_SOFTCONN(t) ((t)->tk_flags & RPC_TASK_SOFTCONN)
141 #define RPC_WAS_SENT(t) ((t)->tk_flags & RPC_TASK_SENT)
142
143 #define RPC_TASK_RUNNING 0
144 #define RPC_TASK_QUEUED 1
145 #define RPC_TASK_ACTIVE 2
146
147 #define RPC_IS_RUNNING(t) test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
148 #define rpc_set_running(t) set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
149 #define rpc_test_and_set_running(t) \
150 test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
151 #define rpc_clear_running(t) \
152 do { \
153 smp_mb__before_clear_bit(); \
154 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
155 smp_mb__after_clear_bit(); \
156 } while (0)
157
158 #define RPC_IS_QUEUED(t) test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
159 #define rpc_set_queued(t) set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
160 #define rpc_clear_queued(t) \
161 do { \
162 smp_mb__before_clear_bit(); \
163 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
164 smp_mb__after_clear_bit(); \
165 } while (0)
166
167 #define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)
168
169 /*
170 * Task priorities.
171 * Note: if you change these, you must also change
172 * the task initialization definitions below.
173 */
174 #define RPC_PRIORITY_LOW (-1)
175 #define RPC_PRIORITY_NORMAL (0)
176 #define RPC_PRIORITY_HIGH (1)
177 #define RPC_PRIORITY_PRIVILEGED (2)
178 #define RPC_NR_PRIORITY (1 + RPC_PRIORITY_PRIVILEGED - RPC_PRIORITY_LOW)
179
180 struct rpc_timer {
181 struct timer_list timer;
182 struct list_head list;
183 unsigned long expires;
184 };
185
186 /*
187 * RPC synchronization objects
188 */
189 struct rpc_wait_queue {
190 spinlock_t lock;
191 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
192 pid_t owner; /* process id of last task serviced */
193 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */
194 unsigned char priority; /* current priority */
195 unsigned char count; /* # task groups remaining serviced so far */
196 unsigned char nr; /* # tasks remaining for cookie */
197 unsigned short qlen; /* total # tasks waiting in queue */
198 struct rpc_timer timer_list;
199 #if defined(RPC_DEBUG) || defined(RPC_TRACEPOINTS)
200 const char * name;
201 #endif
202 };
203
204 /*
205 * This is the # requests to send consecutively
206 * from a single cookie. The aim is to improve
207 * performance of NFS operations such as read/write.
208 */
209 #define RPC_BATCH_COUNT 16
210 #define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
211
212 /*
213 * Function prototypes
214 */
215 struct rpc_task *rpc_new_task(const struct rpc_task_setup *);
216 struct rpc_task *rpc_run_task(const struct rpc_task_setup *);
217 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
218 const struct rpc_call_ops *ops);
219 void rpc_put_task(struct rpc_task *);
220 void rpc_put_task_async(struct rpc_task *);
221 void rpc_exit_task(struct rpc_task *);
222 void rpc_exit(struct rpc_task *, int);
223 void rpc_release_calldata(const struct rpc_call_ops *, void *);
224 void rpc_killall_tasks(struct rpc_clnt *);
225 void rpc_execute(struct rpc_task *);
226 void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
227 void rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
228 void rpc_destroy_wait_queue(struct rpc_wait_queue *);
229 void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
230 rpc_action action);
231 void rpc_sleep_on_priority(struct rpc_wait_queue *,
232 struct rpc_task *,
233 rpc_action action,
234 int priority);
235 void rpc_wake_up_queued_task(struct rpc_wait_queue *,
236 struct rpc_task *);
237 void rpc_wake_up(struct rpc_wait_queue *);
238 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
239 struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *,
240 bool (*)(struct rpc_task *, void *),
241 void *);
242 void rpc_wake_up_status(struct rpc_wait_queue *, int);
243 int rpc_queue_empty(struct rpc_wait_queue *);
244 void rpc_delay(struct rpc_task *, unsigned long);
245 void * rpc_malloc(struct rpc_task *, size_t);
246 void rpc_free(void *);
247 int rpciod_up(void);
248 void rpciod_down(void);
249 int __rpc_wait_for_completion_task(struct rpc_task *task, int (*)(void *));
250 #ifdef RPC_DEBUG
251 struct net;
252 void rpc_show_tasks(struct net *);
253 #endif
254 int rpc_init_mempool(void);
255 void rpc_destroy_mempool(void);
256 extern struct workqueue_struct *rpciod_workqueue;
257 void rpc_prepare_task(struct rpc_task *task);
258
rpc_wait_for_completion_task(struct rpc_task * task)259 static inline int rpc_wait_for_completion_task(struct rpc_task *task)
260 {
261 return __rpc_wait_for_completion_task(task, NULL);
262 }
263
rpc_task_set_priority(struct rpc_task * task,unsigned char prio)264 static inline void rpc_task_set_priority(struct rpc_task *task, unsigned char prio)
265 {
266 task->tk_priority = prio - RPC_PRIORITY_LOW;
267 }
268
rpc_task_has_priority(struct rpc_task * task,unsigned char prio)269 static inline int rpc_task_has_priority(struct rpc_task *task, unsigned char prio)
270 {
271 return (task->tk_priority + RPC_PRIORITY_LOW == prio);
272 }
273
274 #if defined(RPC_DEBUG) || defined (RPC_TRACEPOINTS)
rpc_qname(const struct rpc_wait_queue * q)275 static inline const char * rpc_qname(const struct rpc_wait_queue *q)
276 {
277 return ((q && q->name) ? q->name : "unknown");
278 }
279
rpc_assign_waitqueue_name(struct rpc_wait_queue * q,const char * name)280 static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
281 const char *name)
282 {
283 q->name = name;
284 }
285 #else
rpc_assign_waitqueue_name(struct rpc_wait_queue * q,const char * name)286 static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
287 const char *name)
288 {
289 }
290 #endif
291
292 #endif /* _LINUX_SUNRPC_SCHED_H_ */
293