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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 wait_queue_head_t waitq; /* sync: sleep on this q */
35 struct rpc_wait_queue * rpc_waitq; /* RPC wait queue we're on */
36};
37
38/*
39 * This is the RPC task struct
40 */
41struct rpc_task {
42#ifdef RPC_DEBUG
43 unsigned long tk_magic; /* 0xf00baa */
44#endif
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 */
49
50 /*
51 * RPC call state
52 */
53 struct rpc_message tk_msg; /* RPC call info */
54 __u32 * tk_buffer; /* XDR buffer */
55 size_t tk_bufsize;
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 * exit exit async task and report to caller
66 */
67 void (*tk_timeout_fn)(struct rpc_task *);
68 void (*tk_callback)(struct rpc_task *);
69 void (*tk_action)(struct rpc_task *);
70 void (*tk_exit)(struct rpc_task *);
71 void (*tk_release)(struct rpc_task *);
72 void * tk_calldata;
73
74 /*
75 * tk_timer is used for async processing by the RPC scheduling
76 * primitives. You should not access this directly unless
77 * you have a pathological interest in kernel oopses.
78 */
79 struct timer_list tk_timer; /* kernel timer */
80 unsigned long tk_timeout; /* timeout for rpc_sleep() */
81 unsigned short tk_flags; /* misc flags */
82 unsigned char tk_active : 1;/* Task has been activated */
83 unsigned char tk_priority : 2;/* Task priority */
84 unsigned long tk_runstate; /* Task run status */
85 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could
86 * be any workqueue
87 */
88 union {
89 struct work_struct tk_work; /* Async task work queue */
90 struct rpc_wait tk_wait; /* RPC wait */
91 } u;
92#ifdef RPC_DEBUG
93 unsigned short tk_pid; /* debugging aid */
94#endif
95};
96#define tk_auth tk_client->cl_auth
97#define tk_xprt tk_client->cl_xprt
98
99/* support walking a list of tasks on a wait queue */
100#define task_for_each(task, pos, head) \
101 list_for_each(pos, head) \
102 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1)
103
104#define task_for_first(task, head) \
105 if (!list_empty(head) && \
106 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1))
107
108/* .. and walking list of all tasks */
109#define alltask_for_each(task, pos, head) \
110 list_for_each(pos, head) \
111 if ((task=list_entry(pos, struct rpc_task, tk_task)),1)
112
113typedef void (*rpc_action)(struct rpc_task *);
114
115/*
116 * RPC task flags
117 */
118#define RPC_TASK_ASYNC 0x0001 /* is an async task */
119#define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */
120#define RPC_TASK_CHILD 0x0008 /* is child of other task */
121#define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */
122#define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */
123#define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */
124#define RPC_TASK_KILLED 0x0100 /* task was killed */
125#define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */
126#define RPC_TASK_NOINTR 0x0400 /* uninterruptible task */
127
128#define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC)
129#define RPC_IS_CHILD(t) ((t)->tk_flags & RPC_TASK_CHILD)
130#define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER)
131#define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS)
132#define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED)
133#define RPC_IS_ACTIVATED(t) ((t)->tk_active)
134#define RPC_DO_CALLBACK(t) ((t)->tk_callback != NULL)
135#define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT)
136#define RPC_TASK_UNINTERRUPTIBLE(t) ((t)->tk_flags & RPC_TASK_NOINTR)
137
138#define RPC_TASK_RUNNING 0
139#define RPC_TASK_QUEUED 1
140#define RPC_TASK_WAKEUP 2
141#define RPC_TASK_HAS_TIMER 3
142
143#define RPC_IS_RUNNING(t) (test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate))
144#define rpc_set_running(t) (set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate))
145#define rpc_test_and_set_running(t) \
146 (test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate))
147#define rpc_clear_running(t) \
148 do { \
149 smp_mb__before_clear_bit(); \
150 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
151 smp_mb__after_clear_bit(); \
152 } while (0)
153
154#define RPC_IS_QUEUED(t) (test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate))
155#define rpc_set_queued(t) (set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate))
156#define rpc_clear_queued(t) \
157 do { \
158 smp_mb__before_clear_bit(); \
159 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
160 smp_mb__after_clear_bit(); \
161 } while (0)
162
163#define rpc_start_wakeup(t) \
164 (test_and_set_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate) == 0)
165#define rpc_finish_wakeup(t) \
166 do { \
167 smp_mb__before_clear_bit(); \
168 clear_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate); \
169 smp_mb__after_clear_bit(); \
170 } while (0)
171
172/*
173 * Task priorities.
174 * Note: if you change these, you must also change
175 * the task initialization definitions below.
176 */
177#define RPC_PRIORITY_LOW 0
178#define RPC_PRIORITY_NORMAL 1
179#define RPC_PRIORITY_HIGH 2
180#define RPC_NR_PRIORITY (RPC_PRIORITY_HIGH+1)
181
182/*
183 * RPC synchronization objects
184 */
185struct rpc_wait_queue {
186 spinlock_t lock;
187 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
188 unsigned long cookie; /* cookie of last task serviced */
189 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */
190 unsigned char priority; /* current priority */
191 unsigned char count; /* # task groups remaining serviced so far */
192 unsigned char nr; /* # tasks remaining for cookie */
193#ifdef RPC_DEBUG
194 const char * name;
195#endif
196};
197
198/*
199 * This is the # requests to send consecutively
200 * from a single cookie. The aim is to improve
201 * performance of NFS operations such as read/write.
202 */
203#define RPC_BATCH_COUNT 16
204
205#ifndef RPC_DEBUG
206# define RPC_WAITQ_INIT(var,qname) { \
207 .lock = SPIN_LOCK_UNLOCKED, \
208 .tasks = { \
209 [0] = LIST_HEAD_INIT(var.tasks[0]), \
210 [1] = LIST_HEAD_INIT(var.tasks[1]), \
211 [2] = LIST_HEAD_INIT(var.tasks[2]), \
212 }, \
213 }
214#else
215# define RPC_WAITQ_INIT(var,qname) { \
216 .lock = SPIN_LOCK_UNLOCKED, \
217 .tasks = { \
218 [0] = LIST_HEAD_INIT(var.tasks[0]), \
219 [1] = LIST_HEAD_INIT(var.tasks[1]), \
220 [2] = LIST_HEAD_INIT(var.tasks[2]), \
221 }, \
222 .name = qname, \
223 }
224#endif
225# define RPC_WAITQ(var,qname) struct rpc_wait_queue var = RPC_WAITQ_INIT(var,qname)
226
227#define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
228
229/*
230 * Function prototypes
231 */
232struct rpc_task *rpc_new_task(struct rpc_clnt *, rpc_action, int flags);
233struct rpc_task *rpc_new_child(struct rpc_clnt *, struct rpc_task *parent);
234void rpc_init_task(struct rpc_task *, struct rpc_clnt *,
235 rpc_action exitfunc, int flags);
236void rpc_release_task(struct rpc_task *);
237void rpc_killall_tasks(struct rpc_clnt *);
238int rpc_execute(struct rpc_task *);
239void rpc_run_child(struct rpc_task *parent, struct rpc_task *child,
240 rpc_action action);
241void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
242void rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
243void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
244 rpc_action action, rpc_action timer);
245void rpc_wake_up_task(struct rpc_task *);
246void rpc_wake_up(struct rpc_wait_queue *);
247struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
248void rpc_wake_up_status(struct rpc_wait_queue *, int);
249void rpc_delay(struct rpc_task *, unsigned long);
250void * rpc_malloc(struct rpc_task *, size_t);
251int rpciod_up(void);
252void rpciod_down(void);
253void rpciod_wake_up(void);
254#ifdef RPC_DEBUG
255void rpc_show_tasks(void);
256#endif
257int rpc_init_mempool(void);
258void rpc_destroy_mempool(void);
259
260static inline void rpc_exit(struct rpc_task *task, int status)
261{
262 task->tk_status = status;
263 task->tk_action = NULL;
264}
265
266#ifdef RPC_DEBUG
267static inline const char * rpc_qname(struct rpc_wait_queue *q)
268{
269 return ((q && q->name) ? q->name : "unknown");
270}
271#endif
272
273#endif /* _LINUX_SUNRPC_SCHED_H_ */