2 * linux/include/linux/sunrpc/sched.h
4 * Scheduling primitives for kernel Sun RPC.
6 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
9 #ifndef _LINUX_SUNRPC_SCHED_H_
10 #define _LINUX_SUNRPC_SCHED_H_
12 #include <linux/timer.h>
13 #include <linux/sunrpc/types.h>
14 #include <linux/rcupdate.h>
15 #include <linux/spinlock.h>
16 #include <linux/wait.h>
17 #include <linux/workqueue.h>
18 #include <linux/sunrpc/xdr.h>
21 * This is the actual RPC procedure call info.
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 */
32 struct rpc_wait_queue;
34 struct list_head list; /* wait queue links */
35 struct list_head links; /* Links to related tasks */
39 * This is the RPC task struct
43 unsigned long tk_magic; /* 0xf00baa */
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 */
54 struct rpc_message tk_msg; /* RPC call info */
59 * callback to be executed after waking up
60 * action next procedure for async tasks
61 * tk_ops caller callbacks
63 void (*tk_callback)(struct rpc_task *);
64 void (*tk_action)(struct rpc_task *);
65 const struct rpc_call_ops *tk_ops;
69 * tk_timer is used for async processing by the RPC scheduling
70 * primitives. You should not access this directly unless
71 * you have a pathological interest in kernel oopses.
73 struct timer_list tk_timer; /* kernel timer */
74 unsigned long tk_timeout; /* timeout for rpc_sleep() */
75 unsigned short tk_flags; /* misc flags */
76 unsigned long tk_runstate; /* Task run status */
77 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could
80 struct rpc_wait_queue *tk_waitqueue; /* RPC wait queue we're on */
82 struct work_struct tk_work; /* Async task work queue */
83 struct rpc_wait tk_wait; /* RPC wait */
84 struct rcu_head tk_rcu; /* for task deletion */
87 unsigned short tk_timeouts; /* maj timeouts */
88 size_t tk_bytes_sent; /* total bytes sent */
89 unsigned long tk_start; /* RPC task init timestamp */
90 long tk_rtt; /* round-trip time (jiffies) */
92 pid_t tk_owner; /* Process id for batching tasks */
93 unsigned char tk_priority : 2;/* Task priority */
96 unsigned short tk_pid; /* debugging aid */
99 #define tk_xprt tk_client->cl_xprt
101 /* support walking a list of tasks on a wait queue */
102 #define task_for_each(task, pos, head) \
103 list_for_each(pos, head) \
104 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1)
106 #define task_for_first(task, head) \
107 if (!list_empty(head) && \
108 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1))
110 typedef void (*rpc_action)(struct rpc_task *);
112 struct rpc_call_ops {
113 void (*rpc_call_prepare)(struct rpc_task *, void *);
114 void (*rpc_call_done)(struct rpc_task *, void *);
115 void (*rpc_release)(void *);
118 struct rpc_task_setup {
119 struct rpc_task *task;
120 struct rpc_clnt *rpc_client;
121 const struct rpc_message *rpc_message;
122 const struct rpc_call_ops *callback_ops;
124 struct workqueue_struct *workqueue;
125 unsigned short flags;
126 signed char priority;
132 #define RPC_TASK_ASYNC 0x0001 /* is an async task */
133 #define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */
134 #define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */
135 #define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */
136 #define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */
137 #define RPC_TASK_KILLED 0x0100 /* task was killed */
138 #define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */
140 #define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC)
141 #define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER)
142 #define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS)
143 #define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED)
144 #define RPC_DO_CALLBACK(t) ((t)->tk_callback != NULL)
145 #define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT)
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
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) \
159 smp_mb__before_clear_bit(); \
160 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
161 smp_mb__after_clear_bit(); \
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) \
168 smp_mb__before_clear_bit(); \
169 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
170 smp_mb__after_clear_bit(); \
173 #define rpc_start_wakeup(t) \
174 (test_and_set_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate) == 0)
175 #define rpc_finish_wakeup(t) \
177 smp_mb__before_clear_bit(); \
178 clear_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate); \
179 smp_mb__after_clear_bit(); \
182 #define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)
186 * Note: if you change these, you must also change
187 * the task initialization definitions below.
189 #define RPC_PRIORITY_LOW (-1)
190 #define RPC_PRIORITY_NORMAL (0)
191 #define RPC_PRIORITY_HIGH (1)
192 #define RPC_NR_PRIORITY (1 + RPC_PRIORITY_HIGH - RPC_PRIORITY_LOW)
195 * RPC synchronization objects
197 struct rpc_wait_queue {
199 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
200 pid_t owner; /* process id of last task serviced */
201 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */
202 unsigned char priority; /* current priority */
203 unsigned char count; /* # task groups remaining serviced so far */
204 unsigned char nr; /* # tasks remaining for cookie */
205 unsigned short qlen; /* total # tasks waiting in queue */
212 * This is the # requests to send consecutively
213 * from a single cookie. The aim is to improve
214 * performance of NFS operations such as read/write.
216 #define RPC_BATCH_COUNT 16
217 #define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
220 * Function prototypes
222 struct rpc_task *rpc_new_task(const struct rpc_task_setup *);
223 struct rpc_task *rpc_run_task(const struct rpc_task_setup *);
224 void rpc_put_task(struct rpc_task *);
225 void rpc_exit_task(struct rpc_task *);
226 void rpc_release_calldata(const struct rpc_call_ops *, void *);
227 void rpc_killall_tasks(struct rpc_clnt *);
228 void rpc_execute(struct rpc_task *);
229 void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
230 void rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
231 void rpc_destroy_wait_queue(struct rpc_wait_queue *);
232 void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
234 void rpc_wake_up_queued_task(struct rpc_wait_queue *,
236 void rpc_wake_up(struct rpc_wait_queue *);
237 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
238 void rpc_wake_up_status(struct rpc_wait_queue *, int);
239 void rpc_delay(struct rpc_task *, unsigned long);
240 void * rpc_malloc(struct rpc_task *, size_t);
241 void rpc_free(void *);
243 void rpciod_down(void);
244 int __rpc_wait_for_completion_task(struct rpc_task *task, int (*)(void *));
246 void rpc_show_tasks(void);
248 int rpc_init_mempool(void);
249 void rpc_destroy_mempool(void);
250 extern struct workqueue_struct *rpciod_workqueue;
252 static inline void rpc_exit(struct rpc_task *task, int status)
254 task->tk_status = status;
255 task->tk_action = rpc_exit_task;
258 static inline int rpc_wait_for_completion_task(struct rpc_task *task)
260 return __rpc_wait_for_completion_task(task, NULL);
264 static inline const char * rpc_qname(struct rpc_wait_queue *q)
266 return ((q && q->name) ? q->name : "unknown");
270 #endif /* _LINUX_SUNRPC_SCHED_H_ */