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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/spinlock.h>
15#include <linux/wait.h>
16#include <linux/workqueue.h>
17#include <linux/sunrpc/xdr.h>
18
19/*
20 * This is the actual RPC procedure call info.
21 */
22struct rpc_procinfo;
23struct rpc_message {
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 */
28};
29
30struct rpc_wait_queue;
31struct rpc_wait {
32 struct list_head list; /* wait queue links */
33 struct list_head links; /* Links to related tasks */
34 struct rpc_wait_queue * rpc_waitq; /* RPC wait queue we're on */
35};
36
37/*
38 * This is the RPC task struct
39 */
40struct rpc_task {
41#ifdef RPC_DEBUG
42 unsigned long tk_magic; /* 0xf00baa */
43#endif
44 struct list_head tk_task; /* global list of tasks */
45 struct rpc_clnt * tk_client; /* RPC client */
46 struct rpc_rqst * tk_rqstp; /* RPC request */
47 int tk_status; /* result of last operation */
48
49 /*
50 * RPC call state
51 */
52 struct rpc_message tk_msg; /* RPC call info */
53 __u32 * tk_buffer; /* XDR buffer */
54 size_t tk_bufsize;
55 __u8 tk_garb_retry;
56 __u8 tk_cred_retry;
57
58 unsigned long tk_cookie; /* Cookie for batching tasks */
59
60 /*
61 * timeout_fn to be executed by timer bottom half
62 * callback to be executed after waking up
63 * action next procedure for async tasks
64 * exit exit async task and report to caller
65 */
66 void (*tk_timeout_fn)(struct rpc_task *);
67 void (*tk_callback)(struct rpc_task *);
68 void (*tk_action)(struct rpc_task *);
69 void (*tk_exit)(struct rpc_task *);
70 void (*tk_release)(struct rpc_task *);
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_active : 1;/* Task has been activated */
82 unsigned char tk_priority : 2;/* Task priority */
83 unsigned long tk_runstate; /* Task run status */
84 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could
85 * be any workqueue
86 */
87 union {
88 struct work_struct tk_work; /* Async task work queue */
89 struct rpc_wait tk_wait; /* RPC wait */
90 } u;
91#ifdef RPC_DEBUG
92 unsigned short tk_pid; /* debugging aid */
93#endif
94};
95#define tk_auth tk_client->cl_auth
96#define tk_xprt tk_client->cl_xprt
97
98/* support walking a list of tasks on a wait queue */
99#define task_for_each(task, pos, head) \
100 list_for_each(pos, head) \
101 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1)
102
103#define task_for_first(task, head) \
104 if (!list_empty(head) && \
105 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1))
106
107/* .. and walking list of all tasks */
108#define alltask_for_each(task, pos, head) \
109 list_for_each(pos, head) \
110 if ((task=list_entry(pos, struct rpc_task, tk_task)),1)
111
112typedef void (*rpc_action)(struct rpc_task *);
113
114/*
115 * RPC task flags
116 */
117#define RPC_TASK_ASYNC 0x0001 /* is an async task */
118#define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */
119#define RPC_TASK_CHILD 0x0008 /* is child of other task */
120#define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */
121#define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */
122#define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */
123#define RPC_TASK_KILLED 0x0100 /* task was killed */
124#define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */
125#define RPC_TASK_NOINTR 0x0400 /* uninterruptible task */
126
127#define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC)
128#define RPC_IS_CHILD(t) ((t)->tk_flags & RPC_TASK_CHILD)
129#define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER)
130#define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS)
131#define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED)
132#define RPC_IS_ACTIVATED(t) ((t)->tk_active)
133#define RPC_DO_CALLBACK(t) ((t)->tk_callback != NULL)
134#define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT)
135#define RPC_TASK_UNINTERRUPTIBLE(t) ((t)->tk_flags & RPC_TASK_NOINTR)
136
137#define RPC_TASK_RUNNING 0
138#define RPC_TASK_QUEUED 1
139#define RPC_TASK_WAKEUP 2
140#define RPC_TASK_HAS_TIMER 3
141
142#define RPC_IS_RUNNING(t) (test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate))
143#define rpc_set_running(t) (set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate))
144#define rpc_test_and_set_running(t) \
145 (test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate))
146#define rpc_clear_running(t) \
147 do { \
148 smp_mb__before_clear_bit(); \
149 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
150 smp_mb__after_clear_bit(); \
151 } while (0)
152
153#define RPC_IS_QUEUED(t) (test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate))
154#define rpc_set_queued(t) (set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate))
155#define rpc_clear_queued(t) \
156 do { \
157 smp_mb__before_clear_bit(); \
158 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
159 smp_mb__after_clear_bit(); \
160 } while (0)
161
162#define rpc_start_wakeup(t) \
163 (test_and_set_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate) == 0)
164#define rpc_finish_wakeup(t) \
165 do { \
166 smp_mb__before_clear_bit(); \
167 clear_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate); \
168 smp_mb__after_clear_bit(); \
169 } while (0)
170
171/*
172 * Task priorities.
173 * Note: if you change these, you must also change
174 * the task initialization definitions below.
175 */
176#define RPC_PRIORITY_LOW 0
177#define RPC_PRIORITY_NORMAL 1
178#define RPC_PRIORITY_HIGH 2
179#define RPC_NR_PRIORITY (RPC_PRIORITY_HIGH+1)
180
181/*
182 * RPC synchronization objects
183 */
184struct rpc_wait_queue {
185 spinlock_t lock;
186 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
187 unsigned long cookie; /* cookie of last task serviced */
188 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */
189 unsigned char priority; /* current priority */
190 unsigned char count; /* # task groups remaining serviced so far */
191 unsigned char nr; /* # tasks remaining for cookie */
192#ifdef RPC_DEBUG
193 const char * name;
194#endif
195};
196
197/*
198 * This is the # requests to send consecutively
199 * from a single cookie. The aim is to improve
200 * performance of NFS operations such as read/write.
201 */
202#define RPC_BATCH_COUNT 16
203
204#ifndef RPC_DEBUG
205# define RPC_WAITQ_INIT(var,qname) { \
206 .lock = SPIN_LOCK_UNLOCKED, \
207 .tasks = { \
208 [0] = LIST_HEAD_INIT(var.tasks[0]), \
209 [1] = LIST_HEAD_INIT(var.tasks[1]), \
210 [2] = LIST_HEAD_INIT(var.tasks[2]), \
211 }, \
212 }
213#else
214# define RPC_WAITQ_INIT(var,qname) { \
215 .lock = SPIN_LOCK_UNLOCKED, \
216 .tasks = { \
217 [0] = LIST_HEAD_INIT(var.tasks[0]), \
218 [1] = LIST_HEAD_INIT(var.tasks[1]), \
219 [2] = LIST_HEAD_INIT(var.tasks[2]), \
220 }, \
221 .name = qname, \
222 }
223#endif
224# define RPC_WAITQ(var,qname) struct rpc_wait_queue var = RPC_WAITQ_INIT(var,qname)
225
226#define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
227
228/*
229 * Function prototypes
230 */
231struct rpc_task *rpc_new_task(struct rpc_clnt *, rpc_action, int flags);
232struct rpc_task *rpc_new_child(struct rpc_clnt *, struct rpc_task *parent);
233void rpc_init_task(struct rpc_task *, struct rpc_clnt *,
234 rpc_action exitfunc, int flags);
235void rpc_release_task(struct rpc_task *);
236void rpc_killall_tasks(struct rpc_clnt *);
237int rpc_execute(struct rpc_task *);
238void rpc_run_child(struct rpc_task *parent, struct rpc_task *child,
239 rpc_action action);
240void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
241void rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
242void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
243 rpc_action action, rpc_action timer);
244void rpc_wake_up_task(struct rpc_task *);
245void rpc_wake_up(struct rpc_wait_queue *);
246struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
247void rpc_wake_up_status(struct rpc_wait_queue *, int);
248void rpc_delay(struct rpc_task *, unsigned long);
249void * rpc_malloc(struct rpc_task *, size_t);
250int rpciod_up(void);
251void rpciod_down(void);
252void rpciod_wake_up(void);
253#ifdef RPC_DEBUG
254void rpc_show_tasks(void);
255#endif
256int rpc_init_mempool(void);
257void rpc_destroy_mempool(void);
258
259static inline void rpc_exit(struct rpc_task *task, int status)
260{
261 task->tk_status = status;
262 task->tk_action = NULL;
263}
264
265#ifdef RPC_DEBUG
266static inline const char * rpc_qname(struct rpc_wait_queue *q)
267{
268 return ((q && q->name) ? q->name : "unknown");
269}
270#endif
271
272#endif /* _LINUX_SUNRPC_SCHED_H_ */