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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_auth tk_client->cl_auth 102#define tk_xprt tk_client->cl_xprt 103 104/* support walking a list of tasks on a wait queue */ 105#define task_for_each(task, pos, head) \ 106 list_for_each(pos, head) \ 107 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1) 108 109#define task_for_first(task, head) \ 110 if (!list_empty(head) && \ 111 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1)) 112 113/* .. and walking list of all tasks */ 114#define alltask_for_each(task, pos, head) \ 115 list_for_each(pos, head) \ 116 if ((task=list_entry(pos, struct rpc_task, tk_task)),1) 117 118typedef void (*rpc_action)(struct rpc_task *); 119 120struct rpc_call_ops { 121 void (*rpc_call_prepare)(struct rpc_task *, void *); 122 void (*rpc_call_done)(struct rpc_task *, void *); 123 void (*rpc_release)(void *); 124}; 125 126 127/* 128 * RPC task flags 129 */ 130#define RPC_TASK_ASYNC 0x0001 /* is an async task */ 131#define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */ 132#define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */ 133#define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */ 134#define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */ 135#define RPC_TASK_KILLED 0x0100 /* task was killed */ 136#define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */ 137#define RPC_TASK_NOINTR 0x0400 /* uninterruptible task */ 138 139#define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC) 140#define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER) 141#define RPC_DO_ROOTOVERRIDE(t) ((t)->tk_flags & RPC_TASK_ROOTCREDS) 142#define RPC_ASSASSINATED(t) ((t)->tk_flags & RPC_TASK_KILLED) 143#define RPC_DO_CALLBACK(t) ((t)->tk_callback != NULL) 144#define RPC_IS_SOFT(t) ((t)->tk_flags & RPC_TASK_SOFT) 145#define RPC_TASK_UNINTERRUPTIBLE(t) ((t)->tk_flags & RPC_TASK_NOINTR) 146 147#define RPC_TASK_RUNNING 0 148#define RPC_TASK_QUEUED 1 149#define RPC_TASK_WAKEUP 2 150#define RPC_TASK_HAS_TIMER 3 151#define RPC_TASK_ACTIVE 4 152 153#define RPC_IS_RUNNING(t) test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) 154#define rpc_set_running(t) set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) 155#define rpc_test_and_set_running(t) \ 156 test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) 157#define rpc_clear_running(t) \ 158 do { \ 159 smp_mb__before_clear_bit(); \ 160 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \ 161 smp_mb__after_clear_bit(); \ 162 } while (0) 163 164#define RPC_IS_QUEUED(t) test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate) 165#define rpc_set_queued(t) set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate) 166#define rpc_clear_queued(t) \ 167 do { \ 168 smp_mb__before_clear_bit(); \ 169 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \ 170 smp_mb__after_clear_bit(); \ 171 } while (0) 172 173#define rpc_start_wakeup(t) \ 174 (test_and_set_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate) == 0) 175#define rpc_finish_wakeup(t) \ 176 do { \ 177 smp_mb__before_clear_bit(); \ 178 clear_bit(RPC_TASK_WAKEUP, &(t)->tk_runstate); \ 179 smp_mb__after_clear_bit(); \ 180 } while (0) 181 182#define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate) 183 184/* 185 * Task priorities. 186 * Note: if you change these, you must also change 187 * the task initialization definitions below. 188 */ 189#define RPC_PRIORITY_LOW 0 190#define RPC_PRIORITY_NORMAL 1 191#define RPC_PRIORITY_HIGH 2 192#define RPC_NR_PRIORITY (RPC_PRIORITY_HIGH+1) 193 194/* 195 * RPC synchronization objects 196 */ 197struct rpc_wait_queue { 198 spinlock_t lock; 199 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */ 200 unsigned long cookie; /* cookie of last task serviced */ 201 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */ 202 unsigned char priority; /* current priority */ 203 unsigned char count; /* # task groups remaining serviced so far */ 204 unsigned char nr; /* # tasks remaining for cookie */ 205 unsigned short qlen; /* total # tasks waiting in queue */ 206#ifdef RPC_DEBUG 207 const char * name; 208#endif 209}; 210 211/* 212 * This is the # requests to send consecutively 213 * from a single cookie. The aim is to improve 214 * performance of NFS operations such as read/write. 215 */ 216#define RPC_BATCH_COUNT 16 217 218#ifndef RPC_DEBUG 219# define RPC_WAITQ_INIT(var,qname) { \ 220 .lock = __SPIN_LOCK_UNLOCKED(var.lock), \ 221 .tasks = { \ 222 [0] = LIST_HEAD_INIT(var.tasks[0]), \ 223 [1] = LIST_HEAD_INIT(var.tasks[1]), \ 224 [2] = LIST_HEAD_INIT(var.tasks[2]), \ 225 }, \ 226 } 227#else 228# define RPC_WAITQ_INIT(var,qname) { \ 229 .lock = __SPIN_LOCK_UNLOCKED(var.lock), \ 230 .tasks = { \ 231 [0] = LIST_HEAD_INIT(var.tasks[0]), \ 232 [1] = LIST_HEAD_INIT(var.tasks[1]), \ 233 [2] = LIST_HEAD_INIT(var.tasks[2]), \ 234 }, \ 235 .name = qname, \ 236 } 237#endif 238# define RPC_WAITQ(var,qname) struct rpc_wait_queue var = RPC_WAITQ_INIT(var,qname) 239 240#define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0) 241 242/* 243 * Function prototypes 244 */ 245struct rpc_task *rpc_new_task(struct rpc_clnt *, int flags, 246 const struct rpc_call_ops *ops, void *data); 247struct rpc_task *rpc_run_task(struct rpc_clnt *clnt, int flags, 248 const struct rpc_call_ops *ops, void *data); 249void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt, 250 int flags, const struct rpc_call_ops *ops, 251 void *data); 252void rpc_put_task(struct rpc_task *); 253void rpc_exit_task(struct rpc_task *); 254void rpc_release_calldata(const struct rpc_call_ops *, void *); 255void rpc_killall_tasks(struct rpc_clnt *); 256void rpc_execute(struct rpc_task *); 257void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *); 258void rpc_init_wait_queue(struct rpc_wait_queue *, const char *); 259void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *, 260 rpc_action action, rpc_action timer); 261void rpc_wake_up_task(struct rpc_task *); 262void rpc_wake_up(struct rpc_wait_queue *); 263struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *); 264void rpc_wake_up_status(struct rpc_wait_queue *, int); 265void rpc_delay(struct rpc_task *, unsigned long); 266void * rpc_malloc(struct rpc_task *, size_t); 267void rpc_free(struct rpc_task *); 268int rpciod_up(void); 269void rpciod_down(void); 270int __rpc_wait_for_completion_task(struct rpc_task *task, int (*)(void *)); 271#ifdef RPC_DEBUG 272void rpc_show_tasks(void); 273#endif 274int rpc_init_mempool(void); 275void rpc_destroy_mempool(void); 276extern struct workqueue_struct *rpciod_workqueue; 277 278static inline void rpc_exit(struct rpc_task *task, int status) 279{ 280 task->tk_status = status; 281 task->tk_action = rpc_exit_task; 282} 283 284static inline int rpc_wait_for_completion_task(struct rpc_task *task) 285{ 286 return __rpc_wait_for_completion_task(task, NULL); 287} 288 289#ifdef RPC_DEBUG 290static inline const char * rpc_qname(struct rpc_wait_queue *q) 291{ 292 return ((q && q->name) ? q->name : "unknown"); 293} 294#endif 295 296#endif /* _LINUX_SUNRPC_SCHED_H_ */