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Linux kernel mirror (for testing)
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linux
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/rcupdate.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 */
23struct rpc_procinfo;
24struct 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
31struct rpc_call_ops;
32struct rpc_wait_queue;
33struct rpc_wait {
34 struct list_head list; /* wait queue links */
35 struct list_head links; /* Links to related tasks */
36 struct rpc_wait_queue * rpc_waitq; /* RPC wait queue we're on */
37};
38
39/*
40 * This is the RPC task struct
41 */
42struct rpc_task {
43#ifdef RPC_DEBUG
44 unsigned long tk_magic; /* 0xf00baa */
45#endif
46 atomic_t tk_count; /* Reference count */
47 struct list_head tk_task; /* global list of tasks */
48 struct rpc_clnt * tk_client; /* RPC client */
49 struct rpc_rqst * tk_rqstp; /* RPC request */
50 int tk_status; /* result of last operation */
51
52 /*
53 * RPC call state
54 */
55 struct rpc_message tk_msg; /* RPC call info */
56 __u8 tk_garb_retry;
57 __u8 tk_cred_retry;
58
59 unsigned long tk_cookie; /* Cookie for batching tasks */
60
61 /*
62 * timeout_fn to be executed by timer bottom half
63 * callback to be executed after waking up
64 * action next procedure for async tasks
65 * tk_ops caller callbacks
66 */
67 void (*tk_timeout_fn)(struct rpc_task *);
68 void (*tk_callback)(struct rpc_task *);
69 void (*tk_action)(struct rpc_task *);
70 const struct rpc_call_ops *tk_ops;
71 void * tk_calldata;
72
73 /*
74 * tk_timer is used for async processing by the RPC scheduling
75 * primitives. You should not access this directly unless
76 * you have a pathological interest in kernel oopses.
77 */
78 struct timer_list tk_timer; /* kernel timer */
79 unsigned long tk_timeout; /* timeout for rpc_sleep() */
80 unsigned short tk_flags; /* misc flags */
81 unsigned char tk_priority : 2;/* Task priority */
82 unsigned long tk_runstate; /* Task run status */
83 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could
84 * be any workqueue
85 */
86 union {
87 struct work_struct tk_work; /* Async task work queue */
88 struct rpc_wait tk_wait; /* RPC wait */
89 struct rcu_head tk_rcu; /* for task deletion */
90 } u;
91
92 unsigned short tk_timeouts; /* maj timeouts */
93 size_t tk_bytes_sent; /* total bytes sent */
94 unsigned long tk_start; /* RPC task init timestamp */
95 long tk_rtt; /* round-trip time (jiffies) */
96
97#ifdef RPC_DEBUG
98 unsigned short tk_pid; /* debugging aid */
99#endif
100};
101#define tk_xprt tk_client->cl_xprt
102
103/* support walking a list of tasks on a wait queue */
104#define task_for_each(task, pos, head) \
105 list_for_each(pos, head) \
106 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1)
107
108#define task_for_first(task, head) \
109 if (!list_empty(head) && \
110 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1))
111
112typedef void (*rpc_action)(struct rpc_task *);
113
114struct rpc_call_ops {
115 void (*rpc_call_prepare)(struct rpc_task *, void *);
116 void (*rpc_call_done)(struct rpc_task *, void *);
117 void (*rpc_release)(void *);
118};
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_NOINTR 0x0400 /* uninterruptible task */
132
133#define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC)
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_DO_CALLBACK(t) ((t)->tk_callback != NULL)
138#define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT)
139#define RPC_TASK_UNINTERRUPTIBLE(t) ((t)->tk_flags & RPC_TASK_NOINTR)
140
141#define RPC_TASK_RUNNING 0
142#define RPC_TASK_QUEUED 1
143#define RPC_TASK_WAKEUP 2
144#define RPC_TASK_HAS_TIMER 3
145#define RPC_TASK_ACTIVE 4
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_start_wakeup(t) \
168 (test_and_set_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate) == 0)
169#define rpc_finish_wakeup(t) \
170 do { \
171 smp_mb__before_clear_bit(); \
172 clear_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate); \
173 smp_mb__after_clear_bit(); \
174 } while (0)
175
176#define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)
177
178/*
179 * Task priorities.
180 * Note: if you change these, you must also change
181 * the task initialization definitions below.
182 */
183#define RPC_PRIORITY_LOW 0
184#define RPC_PRIORITY_NORMAL 1
185#define RPC_PRIORITY_HIGH 2
186#define RPC_NR_PRIORITY (RPC_PRIORITY_HIGH+1)
187
188/*
189 * RPC synchronization objects
190 */
191struct rpc_wait_queue {
192 spinlock_t lock;
193 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
194 unsigned long cookie; /* cookie of last task serviced */
195 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */
196 unsigned char priority; /* current priority */
197 unsigned char count; /* # task groups remaining serviced so far */
198 unsigned char nr; /* # tasks remaining for cookie */
199 unsigned short qlen; /* total # tasks waiting in queue */
200#ifdef RPC_DEBUG
201 const char * name;
202#endif
203};
204
205/*
206 * This is the # requests to send consecutively
207 * from a single cookie. The aim is to improve
208 * performance of NFS operations such as read/write.
209 */
210#define RPC_BATCH_COUNT 16
211
212#ifndef RPC_DEBUG
213# define RPC_WAITQ_INIT(var,qname) { \
214 .lock = __SPIN_LOCK_UNLOCKED(var.lock), \
215 .tasks = { \
216 [0] = LIST_HEAD_INIT(var.tasks[0]), \
217 [1] = LIST_HEAD_INIT(var.tasks[1]), \
218 [2] = LIST_HEAD_INIT(var.tasks[2]), \
219 }, \
220 }
221#else
222# define RPC_WAITQ_INIT(var,qname) { \
223 .lock = __SPIN_LOCK_UNLOCKED(var.lock), \
224 .tasks = { \
225 [0] = LIST_HEAD_INIT(var.tasks[0]), \
226 [1] = LIST_HEAD_INIT(var.tasks[1]), \
227 [2] = LIST_HEAD_INIT(var.tasks[2]), \
228 }, \
229 .name = qname, \
230 }
231#endif
232# define RPC_WAITQ(var,qname) struct rpc_wait_queue var = RPC_WAITQ_INIT(var,qname)
233
234#define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
235
236/*
237 * Function prototypes
238 */
239struct rpc_task *rpc_new_task(struct rpc_clnt *, int flags,
240 const struct rpc_call_ops *ops, void *data);
241struct rpc_task *rpc_run_task(struct rpc_clnt *clnt, int flags,
242 const struct rpc_call_ops *ops, void *data);
243void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt,
244 int flags, const struct rpc_call_ops *ops,
245 void *data);
246void rpc_put_task(struct rpc_task *);
247void rpc_exit_task(struct rpc_task *);
248void rpc_release_calldata(const struct rpc_call_ops *, void *);
249void rpc_killall_tasks(struct rpc_clnt *);
250void rpc_execute(struct rpc_task *);
251void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
252void rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
253void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
254 rpc_action action, rpc_action timer);
255void rpc_wake_up_task(struct rpc_task *);
256void rpc_wake_up(struct rpc_wait_queue *);
257struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
258void rpc_wake_up_status(struct rpc_wait_queue *, int);
259void rpc_delay(struct rpc_task *, unsigned long);
260void * rpc_malloc(struct rpc_task *, size_t);
261void rpc_free(void *);
262int rpciod_up(void);
263void rpciod_down(void);
264int __rpc_wait_for_completion_task(struct rpc_task *task, int (*)(void *));
265#ifdef RPC_DEBUG
266void rpc_show_tasks(void);
267#endif
268int rpc_init_mempool(void);
269void rpc_destroy_mempool(void);
270extern struct workqueue_struct *rpciod_workqueue;
271
272static inline void rpc_exit(struct rpc_task *task, int status)
273{
274 task->tk_status = status;
275 task->tk_action = rpc_exit_task;
276}
277
278static inline int rpc_wait_for_completion_task(struct rpc_task *task)
279{
280 return __rpc_wait_for_completion_task(task, NULL);
281}
282
283#ifdef RPC_DEBUG
284static inline const char * rpc_qname(struct rpc_wait_queue *q)
285{
286 return ((q && q->name) ? q->name : "unknown");
287}
288#endif
289
290#endif /* _LINUX_SUNRPC_SCHED_H_ */