[deliverable/linux.git] / include / linux / sunrpc / sched.h

/*
 * linux/include/linux/sunrpc/sched.h
 *
 * Scheduling primitives for kernel Sun RPC.
 *
 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
 */

#ifndef _LINUX_SUNRPC_SCHED_H_
#define _LINUX_SUNRPC_SCHED_H_

#include <linux/timer.h>
#include <linux/sunrpc/types.h>
#include <linux/rcupdate.h>
#include <linux/spinlock.h>
#include <linux/wait.h>
#include <linux/workqueue.h>
#include <linux/sunrpc/xdr.h>

/*
 * This is the actual RPC procedure call info.
 */
struct rpc_procinfo;
struct rpc_message {
	struct rpc_procinfo *	rpc_proc;	/* Procedure information */
	void *			rpc_argp;	/* Arguments */
	void *			rpc_resp;	/* Result */
	struct rpc_cred *	rpc_cred;	/* Credentials */
};

struct rpc_call_ops;
struct rpc_wait_queue;
struct rpc_wait {
	struct list_head	list;		/* wait queue links */
	struct list_head	links;		/* Links to related tasks */
	struct list_head	timer_list;	/* Timer list */
	unsigned long		expires;
};

/*
 * This is the RPC task struct
 */
struct rpc_task {
#ifdef RPC_DEBUG
	unsigned long		tk_magic;	/* 0xf00baa */
#endif
	atomic_t		tk_count;	/* Reference count */
	struct list_head	tk_task;	/* global list of tasks */
	struct rpc_clnt *	tk_client;	/* RPC client */
	struct rpc_rqst *	tk_rqstp;	/* RPC request */
	int			tk_status;	/* result of last operation */

	/*
	 * RPC call state
	 */
	struct rpc_message	tk_msg;		/* RPC call info */
	__u8			tk_garb_retry;
	__u8			tk_cred_retry;

	/*
	 * callback	to be executed after waking up
	 * action	next procedure for async tasks
	 * tk_ops	caller callbacks
	 */
	void			(*tk_callback)(struct rpc_task *);
	void			(*tk_action)(struct rpc_task *);
	const struct rpc_call_ops *tk_ops;
	void *			tk_calldata;

	unsigned long		tk_timeout;	/* timeout for rpc_sleep() */
	unsigned short		tk_flags;	/* misc flags */
	unsigned long		tk_runstate;	/* Task run status */
	struct workqueue_struct	*tk_workqueue;	/* Normally rpciod, but could
						 * be any workqueue
						 */
	struct rpc_wait_queue 	*tk_waitqueue;	/* RPC wait queue we're on */
	union {
		struct work_struct	tk_work;	/* Async task work queue */
		struct rpc_wait		tk_wait;	/* RPC wait */
		struct rcu_head		tk_rcu;		/* for task deletion */
	} u;

	unsigned short		tk_timeouts;	/* maj timeouts */
	size_t			tk_bytes_sent;	/* total bytes sent */
	unsigned long		tk_start;	/* RPC task init timestamp */
	long			tk_rtt;		/* round-trip time (jiffies) */

	pid_t			tk_owner;	/* Process id for batching tasks */
	unsigned char		tk_priority : 2;/* Task priority */

#ifdef RPC_DEBUG
	unsigned short		tk_pid;		/* debugging aid */
#endif
};
#define tk_xprt			tk_client->cl_xprt

/* support walking a list of tasks on a wait queue */
#define	task_for_each(task, pos, head) \
	list_for_each(pos, head) \
		if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1)

#define	task_for_first(task, head) \
	if (!list_empty(head) &&  \
	    ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1))

typedef void			(*rpc_action)(struct rpc_task *);

struct rpc_call_ops {
	void (*rpc_call_prepare)(struct rpc_task *, void *);
	void (*rpc_call_done)(struct rpc_task *, void *);
	void (*rpc_release)(void *);
};

struct rpc_task_setup {
	struct rpc_task *task;
	struct rpc_clnt *rpc_client;
	const struct rpc_message *rpc_message;
	const struct rpc_call_ops *callback_ops;
	void *callback_data;
	struct workqueue_struct *workqueue;
	unsigned short flags;
	signed char priority;
};

/*
 * RPC task flags
 */
#define RPC_TASK_ASYNC		0x0001		/* is an async task */
#define RPC_TASK_SWAPPER	0x0002		/* is swapping in/out */
#define RPC_CALL_MAJORSEEN	0x0020		/* major timeout seen */
#define RPC_TASK_ROOTCREDS	0x0040		/* force root creds */
#define RPC_TASK_DYNAMIC	0x0080		/* task was kmalloc'ed */
#define RPC_TASK_KILLED		0x0100		/* task was killed */
#define RPC_TASK_SOFT		0x0200		/* Use soft timeouts */

#define RPC_IS_ASYNC(t)		((t)->tk_flags & RPC_TASK_ASYNC)
#define RPC_IS_SWAPPER(t)	((t)->tk_flags & RPC_TASK_SWAPPER)
#define RPC_DO_ROOTOVERRIDE(t)	((t)->tk_flags & RPC_TASK_ROOTCREDS)
#define RPC_ASSASSINATED(t)	((t)->tk_flags & RPC_TASK_KILLED)
#define RPC_DO_CALLBACK(t)	((t)->tk_callback != NULL)
#define RPC_IS_SOFT(t)		((t)->tk_flags & RPC_TASK_SOFT)

#define RPC_TASK_RUNNING	0
#define RPC_TASK_QUEUED		1
#define RPC_TASK_WAKEUP		2
#define RPC_TASK_ACTIVE		3

#define RPC_IS_RUNNING(t)	test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
#define rpc_set_running(t)	set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
#define rpc_test_and_set_running(t) \
				test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
#define rpc_clear_running(t)	\
	do { \
		smp_mb__before_clear_bit(); \
		clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
		smp_mb__after_clear_bit(); \
	} while (0)

#define RPC_IS_QUEUED(t)	test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
#define rpc_set_queued(t)	set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
#define rpc_clear_queued(t)	\
	do { \
		smp_mb__before_clear_bit(); \
		clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
		smp_mb__after_clear_bit(); \
	} while (0)

#define rpc_start_wakeup(t) \
	(test_and_set_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate) == 0)
#define rpc_finish_wakeup(t) \
	do { \
		smp_mb__before_clear_bit(); \
		clear_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate); \
		smp_mb__after_clear_bit(); \
	} while (0)

#define RPC_IS_ACTIVATED(t)	test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)

/*
 * Task priorities.
 * Note: if you change these, you must also change
 * the task initialization definitions below.
 */
#define RPC_PRIORITY_LOW	(-1)
#define RPC_PRIORITY_NORMAL	(0)
#define RPC_PRIORITY_HIGH	(1)
#define RPC_NR_PRIORITY		(1 + RPC_PRIORITY_HIGH - RPC_PRIORITY_LOW)

struct rpc_timer {
	struct timer_list timer;
	struct list_head list;
	unsigned long expires;
};

/*
 * RPC synchronization objects
 */
struct rpc_wait_queue {
	spinlock_t		lock;
	struct list_head	tasks[RPC_NR_PRIORITY];	/* task queue for each priority level */
	pid_t			owner;			/* process id of last task serviced */
	unsigned char		maxpriority;		/* maximum priority (0 if queue is not a priority queue) */
	unsigned char		priority;		/* current priority */
	unsigned char		count;			/* # task groups remaining serviced so far */
	unsigned char		nr;			/* # tasks remaining for cookie */
	unsigned short		qlen;			/* total # tasks waiting in queue */
	struct rpc_timer	timer_list;
#ifdef RPC_DEBUG
	const char *		name;
#endif
};

/*
 * This is the # requests to send consecutively
 * from a single cookie.  The aim is to improve
 * performance of NFS operations such as read/write.
 */
#define RPC_BATCH_COUNT			16
#define RPC_IS_PRIORITY(q)		((q)->maxpriority > 0)

/*
 * Function prototypes
 */
struct rpc_task *rpc_new_task(const struct rpc_task_setup *);
struct rpc_task *rpc_run_task(const struct rpc_task_setup *);
void		rpc_put_task(struct rpc_task *);
void		rpc_exit_task(struct rpc_task *);
void		rpc_release_calldata(const struct rpc_call_ops *, void *);
void		rpc_killall_tasks(struct rpc_clnt *);
void		rpc_execute(struct rpc_task *);
void		rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
void		rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
void		rpc_destroy_wait_queue(struct rpc_wait_queue *);
void		rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
					rpc_action action);
void		rpc_wake_up_queued_task(struct rpc_wait_queue *,
					struct rpc_task *);
void		rpc_wake_up(struct rpc_wait_queue *);
struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
void		rpc_wake_up_status(struct rpc_wait_queue *, int);
void		rpc_delay(struct rpc_task *, unsigned long);
void *		rpc_malloc(struct rpc_task *, size_t);
void		rpc_free(void *);
int		rpciod_up(void);
void		rpciod_down(void);
int		__rpc_wait_for_completion_task(struct rpc_task *task, int (*)(void *));
#ifdef RPC_DEBUG
void		rpc_show_tasks(void);
#endif
int		rpc_init_mempool(void);
void		rpc_destroy_mempool(void);
extern struct workqueue_struct *rpciod_workqueue;

static inline void rpc_exit(struct rpc_task *task, int status)
{
	task->tk_status = status;
	task->tk_action = rpc_exit_task;
}

static inline int rpc_wait_for_completion_task(struct rpc_task *task)
{
	return __rpc_wait_for_completion_task(task, NULL);
}

#ifdef RPC_DEBUG
static inline const char * rpc_qname(struct rpc_wait_queue *q)
{
	return ((q && q->name) ? q->name : "unknown");
}
#endif

#endif /* _LINUX_SUNRPC_SCHED_H_ */
Commit	Line	Data
1da177e4 LT	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>
8aca67f0	14	#include <linux/rcupdate.h>
1da177e4 LT	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	*/
	23	struct rpc_procinfo;
	24	struct 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
963d8fe5	31	struct rpc_call_ops;
1da177e4 LT	32	struct rpc_wait_queue;
	33	struct rpc_wait {
	34	struct list_head list; /* wait queue links */
	35	struct list_head links; /* Links to related tasks */
36df9aae TM	36	struct list_head timer_list; /* Timer list */
36df9aae TM	37	unsigned long expires;
1da177e4 LT	38	};
	39
	40	/*
	41	* This is the RPC task struct
	42	*/
	43	struct rpc_task {
	44	#ifdef RPC_DEBUG
	45	unsigned long tk_magic; /* 0xf00baa */
	46	#endif
44c28873	47	atomic_t tk_count; /* Reference count */
1da177e4 LT	48	struct list_head tk_task; /* global list of tasks */
	49	struct rpc_clnt * tk_client; /* RPC client */
	50	struct rpc_rqst * tk_rqstp; /* RPC request */
	51	int tk_status; /* result of last operation */
	52
	53	/*
	54	* RPC call state
	55	*/
	56	struct rpc_message tk_msg; /* RPC call info */
1da177e4 LT	57	__u8 tk_garb_retry;
	58	__u8 tk_cred_retry;
	59
1da177e4	60	/*
1da177e4 LT	61	* callback to be executed after waking up
1da177e4 LT	62	* action next procedure for async tasks
963d8fe5	63	* tk_ops caller callbacks
1da177e4	64	*/
1da177e4 LT	65	void (tk_callback)(struct rpc_task );
1da177e4 LT	66	void (tk_action)(struct rpc_task );
963d8fe5	67	const struct rpc_call_ops *tk_ops;
1da177e4 LT	68	void * tk_calldata;
1da177e4 LT	69
1da177e4 LT	70	unsigned long tk_timeout; /* timeout for rpc_sleep() */
1da177e4 LT	71	unsigned short tk_flags; /* misc flags */
1da177e4 LT	72	unsigned long tk_runstate; /* Task run status */
	73	struct workqueue_struct tk_workqueue; / Normally rpciod, but could
	74	* be any workqueue
	75	*/
96ef13b2	76	struct rpc_wait_queue tk_waitqueue; / RPC wait queue we're on */
1da177e4 LT	77	union {
	78	struct work_struct tk_work; /* Async task work queue */
	79	struct rpc_wait tk_wait; /* RPC wait */
8aca67f0	80	struct rcu_head tk_rcu; /* for task deletion */
1da177e4	81	} u;
ef759a2e CL	82
	83	unsigned short tk_timeouts; /* maj timeouts */
	84	size_t tk_bytes_sent; /* total bytes sent */
	85	unsigned long tk_start; /* RPC task init timestamp */
	86	long tk_rtt; /* round-trip time (jiffies) */
	87
3ff7576d TM	88	pid_t tk_owner; /* Process id for batching tasks */
	89	unsigned char tk_priority : 2;/* Task priority */
	90
1da177e4 LT	91	#ifdef RPC_DEBUG
	92	unsigned short tk_pid; /* debugging aid */
	93	#endif
	94	};
1da177e4 LT	95	#define tk_xprt tk_client->cl_xprt
	96
	97	/* support walking a list of tasks on a wait queue */
	98	#define task_for_each(task, pos, head) \
	99	list_for_each(pos, head) \
	100	if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1)
	101
	102	#define task_for_first(task, head) \
	103	if (!list_empty(head) && \
	104	((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1))
	105
1da177e4 LT	106	typedef void (rpc_action)(struct rpc_task );
1da177e4 LT	107
963d8fe5	108	struct rpc_call_ops {
4ce70ada	109	void (rpc_call_prepare)(struct rpc_task , void *);
963d8fe5 TM	110	void (rpc_call_done)(struct rpc_task , void *);
	111	void (rpc_release)(void );
	112	};
	113
84115e1c	114	struct rpc_task_setup {
e8f5d77c	115	struct rpc_task *task;
84115e1c TM	116	struct rpc_clnt *rpc_client;
	117	const struct rpc_message *rpc_message;
	118	const struct rpc_call_ops *callback_ops;
	119	void *callback_data;
32bfb5c0	120	struct workqueue_struct *workqueue;
84115e1c	121	unsigned short flags;
3ff7576d	122	signed char priority;
84115e1c	123	};
963d8fe5	124
1da177e4 LT	125	/*
	126	* RPC task flags
	127	*/
	128	#define RPC_TASK_ASYNC 0x0001 /* is an async task */
	129	#define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */
1da177e4 LT	130	#define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */
	131	#define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */
	132	#define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */
	133	#define RPC_TASK_KILLED 0x0100 /* task was killed */
	134	#define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */
1da177e4 LT	135
1da177e4 LT	136	#define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC)
1da177e4 LT	137	#define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER)
	138	#define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS)
	139	#define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED)
1da177e4 LT	140	#define RPC_DO_CALLBACK(t) ((t)->tk_callback != NULL)
1da177e4 LT	141	#define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT)
1da177e4 LT	142
	143	#define RPC_TASK_RUNNING 0
	144	#define RPC_TASK_QUEUED 1
	145	#define RPC_TASK_WAKEUP 2
eb276c0e	146	#define RPC_TASK_ACTIVE 3
1da177e4	147
7b8f850b RB	148	#define RPC_IS_RUNNING(t) test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
7b8f850b RB	149	#define rpc_set_running(t) set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
1da177e4	150	#define rpc_test_and_set_running(t) \
7b8f850b	151	test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
1da177e4 LT	152	#define rpc_clear_running(t) \
	153	do { \
	154	smp_mb__before_clear_bit(); \
	155	clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
	156	smp_mb__after_clear_bit(); \
	157	} while (0)
	158
7b8f850b RB	159	#define RPC_IS_QUEUED(t) test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
7b8f850b RB	160	#define rpc_set_queued(t) set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
1da177e4 LT	161	#define rpc_clear_queued(t) \
	162	do { \
	163	smp_mb__before_clear_bit(); \
	164	clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
	165	smp_mb__after_clear_bit(); \
	166	} while (0)
	167
	168	#define rpc_start_wakeup(t) \
	169	(test_and_set_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate) == 0)
	170	#define rpc_finish_wakeup(t) \
	171	do { \
	172	smp_mb__before_clear_bit(); \
	173	clear_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate); \
	174	smp_mb__after_clear_bit(); \
	175	} while (0)
	176
7b8f850b	177	#define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)
44c28873	178
1da177e4 LT	179	/*
	180	* Task priorities.
	181	* Note: if you change these, you must also change
	182	* the task initialization definitions below.
	183	*/
3ff7576d TM	184	#define RPC_PRIORITY_LOW (-1)
	185	#define RPC_PRIORITY_NORMAL (0)
	186	#define RPC_PRIORITY_HIGH (1)
	187	#define RPC_NR_PRIORITY (1 + RPC_PRIORITY_HIGH - RPC_PRIORITY_LOW)
1da177e4	188
36df9aae TM	189	struct rpc_timer {
	190	struct timer_list timer;
	191	struct list_head list;
	192	unsigned long expires;
	193	};
	194
1da177e4 LT	195	/*
	196	* RPC synchronization objects
	197	*/
	198	struct rpc_wait_queue {
	199	spinlock_t lock;
	200	struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
3ff7576d	201	pid_t owner; /* process id of last task serviced */
1da177e4 LT	202	unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */
	203	unsigned char priority; /* current priority */
	204	unsigned char count; /* # task groups remaining serviced so far */
	205	unsigned char nr; /* # tasks remaining for cookie */
e19b63da	206	unsigned short qlen; /* total # tasks waiting in queue */
36df9aae	207	struct rpc_timer timer_list;
1da177e4 LT	208	#ifdef RPC_DEBUG
	209	const char * name;
	210	#endif
	211	};
	212
	213	/*
	214	* This is the # requests to send consecutively
	215	* from a single cookie. The aim is to improve
	216	* performance of NFS operations such as read/write.
	217	*/
	218	#define RPC_BATCH_COUNT 16
1da177e4 LT	219	#define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
	220
	221	/*
	222	* Function prototypes
	223	*/
84115e1c	224	struct rpc_task rpc_new_task(const struct rpc_task_setup );
c970aa85	225	struct rpc_task rpc_run_task(const struct rpc_task_setup );
e6b3c4db	226	void rpc_put_task(struct rpc_task *);
abbcf28f	227	void rpc_exit_task(struct rpc_task *);
bbd5a1f9	228	void rpc_release_calldata(const struct rpc_call_ops , void );
1da177e4	229	void rpc_killall_tasks(struct rpc_clnt *);
2efef837	230	void rpc_execute(struct rpc_task *);
1da177e4 LT	231	void rpc_init_priority_wait_queue(struct rpc_wait_queue , const char );
1da177e4 LT	232	void rpc_init_wait_queue(struct rpc_wait_queue , const char );
f6a1cc89	233	void rpc_destroy_wait_queue(struct rpc_wait_queue *);
1da177e4	234	void rpc_sleep_on(struct rpc_wait_queue , struct rpc_task ,
5d00837b	235	rpc_action action);
96ef13b2 TM	236	void rpc_wake_up_queued_task(struct rpc_wait_queue *,
96ef13b2 TM	237	struct rpc_task *);
1da177e4 LT	238	void rpc_wake_up(struct rpc_wait_queue *);
	239	struct rpc_task rpc_wake_up_next(struct rpc_wait_queue );
	240	void rpc_wake_up_status(struct rpc_wait_queue *, int);
	241	void rpc_delay(struct rpc_task *, unsigned long);
	242	void * rpc_malloc(struct rpc_task *, size_t);
c5a4dd8b	243	void rpc_free(void *);
1da177e4 LT	244	int rpciod_up(void);
1da177e4 LT	245	void rpciod_down(void);
44c28873	246	int __rpc_wait_for_completion_task(struct rpc_task task, int ()(void *));
1da177e4 LT	247	#ifdef RPC_DEBUG
	248	void rpc_show_tasks(void);
	249	#endif
	250	int rpc_init_mempool(void);
	251	void rpc_destroy_mempool(void);
24c5d9d7	252	extern struct workqueue_struct *rpciod_workqueue;
1da177e4 LT	253
	254	static inline void rpc_exit(struct rpc_task *task, int status)
	255	{
	256	task->tk_status = status;
abbcf28f	257	task->tk_action = rpc_exit_task;
1da177e4 LT	258	}
1da177e4 LT	259
44c28873 TM	260	static inline int rpc_wait_for_completion_task(struct rpc_task *task)
	261	{
	262	return __rpc_wait_for_completion_task(task, NULL);
	263	}
	264
1da177e4 LT	265	#ifdef RPC_DEBUG
	266	static 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_ */