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/spinlock.h>
15 #include <linux/wait.h>
16 #include <linux/workqueue.h>
17 #include <linux/sunrpc/xdr.h>
20 * This is the actual RPC procedure call info.
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 */
30 struct rpc_wait_queue;
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 */
39 * This is the RPC task struct
43 unsigned long tk_magic; /* 0xf00baa */
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 */
53 struct rpc_message tk_msg; /* RPC call info */
54 __u32 * tk_buffer; /* XDR buffer */
60 unsigned long tk_cookie; /* Cookie for batching tasks */
63 * timeout_fn to be executed by timer bottom half
64 * callback to be executed after waking up
65 * action next procedure for async tasks
66 * exit exit async task and report to caller
68 void (*tk_timeout_fn)(struct rpc_task *);
69 void (*tk_callback)(struct rpc_task *);
70 void (*tk_action)(struct rpc_task *);
71 void (*tk_exit)(struct rpc_task *);
72 void (*tk_release)(struct rpc_task *);
76 * tk_timer is used for async processing by the RPC scheduling
77 * primitives. You should not access this directly unless
78 * you have a pathological interest in kernel oopses.
80 struct timer_list tk_timer; /* kernel timer */
81 unsigned long tk_timeout; /* timeout for rpc_sleep() */
82 unsigned short tk_flags; /* misc flags */
83 unsigned char tk_active : 1;/* Task has been activated */
84 unsigned char tk_priority : 2;/* Task priority */
85 unsigned long tk_runstate; /* Task run status */
86 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could
90 struct work_struct tk_work; /* Async task work queue */
91 struct rpc_wait tk_wait; /* RPC wait */
94 unsigned short tk_pid; /* debugging aid */
97 #define tk_auth tk_client->cl_auth
98 #define tk_xprt tk_client->cl_xprt
100 /* support walking a list of tasks on a wait queue */
101 #define task_for_each(task, pos, head) \
102 list_for_each(pos, head) \
103 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1)
105 #define task_for_first(task, head) \
106 if (!list_empty(head) && \
107 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1))
109 /* .. and walking list of all tasks */
110 #define alltask_for_each(task, pos, head) \
111 list_for_each(pos, head) \
112 if ((task=list_entry(pos, struct rpc_task, tk_task)),1)
114 typedef void (*rpc_action)(struct rpc_task *);
119 #define RPC_TASK_ASYNC 0x0001 /* is an async task */
120 #define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */
121 #define RPC_TASK_SETUID 0x0004 /* is setuid process */
122 #define RPC_TASK_CHILD 0x0008 /* is child of other task */
123 #define RPC_CALL_REALUID 0x0010 /* try using real uid */
124 #define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */
125 #define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */
126 #define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */
127 #define RPC_TASK_KILLED 0x0100 /* task was killed */
128 #define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */
129 #define RPC_TASK_NOINTR 0x0400 /* uninterruptible task */
131 #define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC)
132 #define RPC_IS_SETUID(t) ((t)->tk_flags & RPC_TASK_SETUID)
133 #define RPC_IS_CHILD(t) ((t)->tk_flags & RPC_TASK_CHILD)
134 #define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER)
135 #define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS)
136 #define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED)
137 #define RPC_IS_ACTIVATED(t) ((t)->tk_active)
138 #define RPC_DO_CALLBACK(t) ((t)->tk_callback != NULL)
139 #define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT)
140 #define RPC_TASK_UNINTERRUPTIBLE(t) ((t)->tk_flags & RPC_TASK_NOINTR)
142 #define RPC_TASK_RUNNING 0
143 #define RPC_TASK_QUEUED 1
144 #define RPC_TASK_WAKEUP 2
145 #define RPC_TASK_HAS_TIMER 3
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) \
153 smp_mb__before_clear_bit(); \
154 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
155 smp_mb__after_clear_bit(); \
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) \
162 smp_mb__before_clear_bit(); \
163 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
164 smp_mb__after_clear_bit(); \
167 #define rpc_start_wakeup(t) \
168 (test_and_set_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate) == 0)
169 #define rpc_finish_wakeup(t) \
171 smp_mb__before_clear_bit(); \
172 clear_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate); \
173 smp_mb__after_clear_bit(); \
178 * Note: if you change these, you must also change
179 * the task initialization definitions below.
181 #define RPC_PRIORITY_LOW 0
182 #define RPC_PRIORITY_NORMAL 1
183 #define RPC_PRIORITY_HIGH 2
184 #define RPC_NR_PRIORITY (RPC_PRIORITY_HIGH+1)
187 * RPC synchronization objects
189 struct rpc_wait_queue {
191 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
192 unsigned long cookie; /* cookie 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 */
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.
207 #define RPC_BATCH_COUNT 16
210 # define RPC_WAITQ_INIT(var,qname) { \
211 .lock = SPIN_LOCK_UNLOCKED, \
213 [0] = LIST_HEAD_INIT(var.tasks[0]), \
214 [1] = LIST_HEAD_INIT(var.tasks[1]), \
215 [2] = LIST_HEAD_INIT(var.tasks[2]), \
219 # define RPC_WAITQ_INIT(var,qname) { \
220 .lock = SPIN_LOCK_UNLOCKED, \
222 [0] = LIST_HEAD_INIT(var.tasks[0]), \
223 [1] = LIST_HEAD_INIT(var.tasks[1]), \
224 [2] = LIST_HEAD_INIT(var.tasks[2]), \
229 # define RPC_WAITQ(var,qname) struct rpc_wait_queue var = RPC_WAITQ_INIT(var,qname)
231 #define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
234 * Function prototypes
236 struct rpc_task *rpc_new_task(struct rpc_clnt *, rpc_action, int flags);
237 struct rpc_task *rpc_new_child(struct rpc_clnt *, struct rpc_task *parent);
238 void rpc_init_task(struct rpc_task *, struct rpc_clnt *,
239 rpc_action exitfunc, int flags);
240 void rpc_release_task(struct rpc_task *);
241 void rpc_killall_tasks(struct rpc_clnt *);
242 int rpc_execute(struct rpc_task *);
243 void rpc_run_child(struct rpc_task *parent, struct rpc_task *child,
245 void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
246 void rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
247 void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
248 rpc_action action, rpc_action timer);
249 void rpc_wake_up_task(struct rpc_task *);
250 void rpc_wake_up(struct rpc_wait_queue *);
251 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
252 void rpc_wake_up_status(struct rpc_wait_queue *, int);
253 void rpc_delay(struct rpc_task *, unsigned long);
254 void * rpc_malloc(struct rpc_task *, size_t);
256 void rpciod_down(void);
257 void rpciod_wake_up(void);
259 void rpc_show_tasks(void);
261 int rpc_init_mempool(void);
262 void rpc_destroy_mempool(void);
264 static inline void rpc_exit(struct rpc_task *task, int status)
266 task->tk_status = status;
267 task->tk_action = NULL;
271 static inline const char * rpc_qname(struct rpc_wait_queue *q)
273 return ((q && q->name) ? q->name : "unknown");
277 #endif /* _LINUX_SUNRPC_SCHED_H_ */