xref: /linux-6.15/include/linux/sunrpc/sched.h (revision 0d5c06aa)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * linux/include/linux/sunrpc/sched.h
4  *
5  * Scheduling primitives for kernel Sun RPC.
6  *
7  * Copyright (C) 1996, Olaf Kirch <[email protected]>
8  */
9 
10 #ifndef _LINUX_SUNRPC_SCHED_H_
11 #define _LINUX_SUNRPC_SCHED_H_
12 
13 #include <linux/timer.h>
14 #include <linux/ktime.h>
15 #include <linux/sunrpc/types.h>
16 #include <linux/spinlock.h>
17 #include <linux/wait_bit.h>
18 #include <linux/workqueue.h>
19 #include <linux/sunrpc/xdr.h>
20 
21 /*
22  * This is the actual RPC procedure call info.
23  */
24 struct rpc_procinfo;
25 struct rpc_message {
26 	const struct rpc_procinfo *rpc_proc;	/* Procedure information */
27 	void *			rpc_argp;	/* Arguments */
28 	void *			rpc_resp;	/* Result */
29 	struct rpc_cred *	rpc_cred;	/* Credentials */
30 };
31 
32 struct rpc_call_ops;
33 struct rpc_wait_queue;
34 struct rpc_wait {
35 	struct list_head	list;		/* wait queue links */
36 	struct list_head	links;		/* Links to related tasks */
37 	struct list_head	timer_list;	/* Timer list */
38 	unsigned long		expires;
39 };
40 
41 /*
42  * This is the RPC task struct
43  */
44 struct rpc_task {
45 	atomic_t		tk_count;	/* Reference count */
46 	int			tk_status;	/* result of last operation */
47 	struct list_head	tk_task;	/* global list of tasks */
48 
49 	/*
50 	 * callback	to be executed after waking up
51 	 * action	next procedure for async tasks
52 	 */
53 	void			(*tk_callback)(struct rpc_task *);
54 	void			(*tk_action)(struct rpc_task *);
55 
56 	unsigned long		tk_timeout;	/* timeout for rpc_sleep() */
57 	unsigned long		tk_runstate;	/* Task run status */
58 
59 	struct rpc_wait_queue 	*tk_waitqueue;	/* RPC wait queue we're on */
60 	union {
61 		struct work_struct	tk_work;	/* Async task work queue */
62 		struct rpc_wait		tk_wait;	/* RPC wait */
63 	} u;
64 
65 	/*
66 	 * RPC call state
67 	 */
68 	struct rpc_message	tk_msg;		/* RPC call info */
69 	void *			tk_calldata;	/* Caller private data */
70 	const struct rpc_call_ops *tk_ops;	/* Caller callbacks */
71 
72 	struct rpc_clnt *	tk_client;	/* RPC client */
73 	struct rpc_xprt *	tk_xprt;	/* Transport */
74 
75 	struct rpc_rqst *	tk_rqstp;	/* RPC request */
76 
77 	struct workqueue_struct	*tk_workqueue;	/* Normally rpciod, but could
78 						 * be any workqueue
79 						 */
80 	ktime_t			tk_start;	/* RPC task init timestamp */
81 
82 	pid_t			tk_owner;	/* Process id for batching tasks */
83 	unsigned short		tk_flags;	/* misc flags */
84 	unsigned short		tk_timeouts;	/* maj timeouts */
85 
86 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
87 	unsigned short		tk_pid;		/* debugging aid */
88 #endif
89 	unsigned char		tk_priority : 2,/* Task priority */
90 				tk_garb_retry : 2,
91 				tk_cred_retry : 2,
92 				tk_rebind_retry : 2;
93 };
94 
95 typedef void			(*rpc_action)(struct rpc_task *);
96 
97 struct rpc_call_ops {
98 	void (*rpc_call_prepare)(struct rpc_task *, void *);
99 	void (*rpc_call_done)(struct rpc_task *, void *);
100 	void (*rpc_count_stats)(struct rpc_task *, void *);
101 	void (*rpc_release)(void *);
102 };
103 
104 struct rpc_task_setup {
105 	struct rpc_task *task;
106 	struct rpc_clnt *rpc_client;
107 	struct rpc_xprt *rpc_xprt;
108 	const struct rpc_message *rpc_message;
109 	const struct rpc_call_ops *callback_ops;
110 	void *callback_data;
111 	struct workqueue_struct *workqueue;
112 	unsigned short flags;
113 	signed char priority;
114 };
115 
116 /*
117  * RPC task flags
118  */
119 #define RPC_TASK_ASYNC		0x0001		/* is an async task */
120 #define RPC_TASK_SWAPPER	0x0002		/* is swapping in/out */
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_SOFTCONN	0x0400		/* Fail if can't connect */
127 #define RPC_TASK_SENT		0x0800		/* message was sent */
128 #define RPC_TASK_TIMEOUT	0x1000		/* fail with ETIMEDOUT on timeout */
129 #define RPC_TASK_NOCONNECT	0x2000		/* return ENOTCONN if not connected */
130 #define RPC_TASK_NO_RETRANS_TIMEOUT	0x4000		/* wait forever for a reply */
131 
132 #define RPC_IS_ASYNC(t)		((t)->tk_flags & RPC_TASK_ASYNC)
133 #define RPC_IS_SWAPPER(t)	((t)->tk_flags & RPC_TASK_SWAPPER)
134 #define RPC_DO_ROOTOVERRIDE(t)	((t)->tk_flags & RPC_TASK_ROOTCREDS)
135 #define RPC_ASSASSINATED(t)	((t)->tk_flags & RPC_TASK_KILLED)
136 #define RPC_IS_SOFT(t)		((t)->tk_flags & (RPC_TASK_SOFT|RPC_TASK_TIMEOUT))
137 #define RPC_IS_SOFTCONN(t)	((t)->tk_flags & RPC_TASK_SOFTCONN)
138 #define RPC_WAS_SENT(t)		((t)->tk_flags & RPC_TASK_SENT)
139 
140 #define RPC_TASK_RUNNING	0
141 #define RPC_TASK_QUEUED		1
142 #define RPC_TASK_ACTIVE		2
143 #define RPC_TASK_NEED_XMIT	3
144 #define RPC_TASK_NEED_RECV	4
145 #define RPC_TASK_MSG_PIN_WAIT	5
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_atomic(); \
154 		clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
155 		smp_mb__after_atomic(); \
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_atomic(); \
163 		clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
164 		smp_mb__after_atomic(); \
165 	} while (0)
166 
167 #define RPC_IS_ACTIVATED(t)	test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)
168 
169 /*
170  * Task priorities.
171  * Note: if you change these, you must also change
172  * the task initialization definitions below.
173  */
174 #define RPC_PRIORITY_LOW	(-1)
175 #define RPC_PRIORITY_NORMAL	(0)
176 #define RPC_PRIORITY_HIGH	(1)
177 #define RPC_PRIORITY_PRIVILEGED	(2)
178 #define RPC_NR_PRIORITY		(1 + RPC_PRIORITY_PRIVILEGED - RPC_PRIORITY_LOW)
179 
180 struct rpc_timer {
181 	struct timer_list timer;
182 	struct list_head list;
183 	unsigned long expires;
184 };
185 
186 /*
187  * RPC synchronization objects
188  */
189 struct rpc_wait_queue {
190 	spinlock_t		lock;
191 	struct list_head	tasks[RPC_NR_PRIORITY];	/* task queue for each priority level */
192 	unsigned char		maxpriority;		/* maximum priority (0 if queue is not a priority queue) */
193 	unsigned char		priority;		/* current priority */
194 	unsigned char		nr;			/* # tasks remaining for cookie */
195 	unsigned short		qlen;			/* total # tasks waiting in queue */
196 	struct rpc_timer	timer_list;
197 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
198 	const char *		name;
199 #endif
200 };
201 
202 /*
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.
206  */
207 #define RPC_IS_PRIORITY(q)		((q)->maxpriority > 0)
208 
209 /*
210  * Function prototypes
211  */
212 struct rpc_task *rpc_new_task(const struct rpc_task_setup *);
213 struct rpc_task *rpc_run_task(const struct rpc_task_setup *);
214 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req);
215 void		rpc_put_task(struct rpc_task *);
216 void		rpc_put_task_async(struct rpc_task *);
217 void		rpc_exit_task(struct rpc_task *);
218 void		rpc_exit(struct rpc_task *, int);
219 void		rpc_release_calldata(const struct rpc_call_ops *, void *);
220 void		rpc_killall_tasks(struct rpc_clnt *);
221 void		rpc_execute(struct rpc_task *);
222 void		rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
223 void		rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
224 void		rpc_destroy_wait_queue(struct rpc_wait_queue *);
225 void		rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
226 					rpc_action action);
227 void		rpc_sleep_on_priority(struct rpc_wait_queue *,
228 					struct rpc_task *,
229 					rpc_action action,
230 					int priority);
231 void rpc_wake_up_queued_task_on_wq(struct workqueue_struct *wq,
232 		struct rpc_wait_queue *queue,
233 		struct rpc_task *task);
234 void		rpc_wake_up_queued_task(struct rpc_wait_queue *,
235 					struct rpc_task *);
236 void		rpc_wake_up_queued_task_set_status(struct rpc_wait_queue *,
237 						   struct rpc_task *,
238 						   int);
239 void		rpc_wake_up(struct rpc_wait_queue *);
240 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
241 struct rpc_task *rpc_wake_up_first_on_wq(struct workqueue_struct *wq,
242 					struct rpc_wait_queue *,
243 					bool (*)(struct rpc_task *, void *),
244 					void *);
245 struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *,
246 					bool (*)(struct rpc_task *, void *),
247 					void *);
248 void		rpc_wake_up_status(struct rpc_wait_queue *, int);
249 void		rpc_delay(struct rpc_task *, unsigned long);
250 int		rpc_malloc(struct rpc_task *);
251 void		rpc_free(struct rpc_task *);
252 int		rpciod_up(void);
253 void		rpciod_down(void);
254 int		__rpc_wait_for_completion_task(struct rpc_task *task, wait_bit_action_f *);
255 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
256 struct net;
257 void		rpc_show_tasks(struct net *);
258 #endif
259 int		rpc_init_mempool(void);
260 void		rpc_destroy_mempool(void);
261 extern struct workqueue_struct *rpciod_workqueue;
262 extern struct workqueue_struct *xprtiod_workqueue;
263 void		rpc_prepare_task(struct rpc_task *task);
264 
265 static inline int rpc_wait_for_completion_task(struct rpc_task *task)
266 {
267 	return __rpc_wait_for_completion_task(task, NULL);
268 }
269 
270 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
271 static inline const char * rpc_qname(const struct rpc_wait_queue *q)
272 {
273 	return ((q && q->name) ? q->name : "unknown");
274 }
275 
276 static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
277 		const char *name)
278 {
279 	q->name = name;
280 }
281 #else
282 static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
283 		const char *name)
284 {
285 }
286 #endif
287 
288 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
289 int rpc_clnt_swap_activate(struct rpc_clnt *clnt);
290 void rpc_clnt_swap_deactivate(struct rpc_clnt *clnt);
291 #else
292 static inline int
293 rpc_clnt_swap_activate(struct rpc_clnt *clnt)
294 {
295 	return -EINVAL;
296 }
297 
298 static inline void
299 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
300 {
301 }
302 #endif /* CONFIG_SUNRPC_SWAP */
303 
304 #endif /* _LINUX_SUNRPC_SCHED_H_ */
305