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_call_ops; 31struct rpc_wait_queue; 32struct rpc_wait { 33 struct list_head list; /* wait queue links */ 34 struct list_head links; /* Links to related tasks */ 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 atomic_t tk_count; /* Reference count */ 46 struct list_head tk_task; /* global list of tasks */ 47 struct rpc_clnt * tk_client; /* RPC client */ 48 struct rpc_rqst * tk_rqstp; /* RPC request */ 49 int tk_status; /* result of last operation */ 50 51 /* 52 * RPC call state 53 */ 54 struct rpc_message tk_msg; /* RPC call info */ 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 * tk_ops caller callbacks 65 */ 66 void (*tk_timeout_fn)(struct rpc_task *); 67 void (*tk_callback)(struct rpc_task *); 68 void (*tk_action)(struct rpc_task *); 69 const struct rpc_call_ops *tk_ops; 70 void * tk_calldata; 71 72 /* 73 * tk_timer is used for async processing by the RPC scheduling 74 * primitives. You should not access this directly unless 75 * you have a pathological interest in kernel oopses. 76 */ 77 struct timer_list tk_timer; /* kernel timer */ 78 unsigned long tk_timeout; /* timeout for rpc_sleep() */ 79 unsigned short tk_flags; /* misc flags */ 80 unsigned char tk_priority : 2;/* Task priority */ 81 unsigned long tk_runstate; /* Task run status */ 82 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could 83 * be any workqueue 84 */ 85 union { 86 struct work_struct tk_work; /* Async task work queue */ 87 struct rpc_wait tk_wait; /* RPC wait */ 88 } u; 89 90 unsigned short tk_timeouts; /* maj timeouts */ 91 size_t tk_bytes_sent; /* total bytes sent */ 92 unsigned long tk_start; /* RPC task init timestamp */ 93 long tk_rtt; /* round-trip time (jiffies) */ 94 95#ifdef RPC_DEBUG 96 unsigned short tk_pid; /* debugging aid */ 97#endif 98}; 99#define tk_auth tk_client->cl_auth 100#define tk_xprt tk_client->cl_xprt 101 102/* support walking a list of tasks on a wait queue */ 103#define task_for_each(task, pos, head) \ 104 list_for_each(pos, head) \ 105 if ((task=list_entry(pos, struct rpc_task, u.tk_wait.list)),1) 106 107#define task_for_first(task, head) \ 108 if (!list_empty(head) && \ 109 ((task=list_entry((head)->next, struct rpc_task, u.tk_wait.list)),1)) 110 111/* .. and walking list of all tasks */ 112#define alltask_for_each(task, pos, head) \ 113 list_for_each(pos, head) \ 114 if ((task=list_entry(pos, struct rpc_task, tk_task)),1) 115 116typedef void (*rpc_action)(struct rpc_task *); 117 118struct rpc_call_ops { 119 void (*rpc_call_prepare)(struct rpc_task *, void *); 120 void (*rpc_call_done)(struct rpc_task *, void *); 121 void (*rpc_release)(void *); 122}; 123 124 125/* 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 */ 130#define RPC_TASK_CHILD 0x0008 /* is child of other task */ 131#define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */ 132#define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */ 133#define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */ 134#define RPC_TASK_KILLED 0x0100 /* task was killed */ 135#define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */ 136#define RPC_TASK_NOINTR 0x0400 /* uninterruptible task */ 137 138#define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC) 139#define RPC_IS_CHILD(t) ((t)->tk_flags & RPC_TASK_CHILD) 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#define rpc_set_active(t) (set_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)) 184#define rpc_clear_active(t) \ 185 do { \ 186 smp_mb__before_clear_bit(); \ 187 clear_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate); \ 188 smp_mb__after_clear_bit(); \ 189 } while(0) 190 191/* 192 * Task priorities. 193 * Note: if you change these, you must also change 194 * the task initialization definitions below. 195 */ 196#define RPC_PRIORITY_LOW 0 197#define RPC_PRIORITY_NORMAL 1 198#define RPC_PRIORITY_HIGH 2 199#define RPC_NR_PRIORITY (RPC_PRIORITY_HIGH+1) 200 201/* 202 * RPC synchronization objects 203 */ 204struct rpc_wait_queue { 205 spinlock_t lock; 206 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */ 207 unsigned long cookie; /* cookie of last task serviced */ 208 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */ 209 unsigned char priority; /* current priority */ 210 unsigned char count; /* # task groups remaining serviced so far */ 211 unsigned char nr; /* # tasks remaining for cookie */ 212 unsigned short qlen; /* total # tasks waiting in queue */ 213#ifdef RPC_DEBUG 214 const char * name; 215#endif 216}; 217 218/* 219 * This is the # requests to send consecutively 220 * from a single cookie. The aim is to improve 221 * performance of NFS operations such as read/write. 222 */ 223#define RPC_BATCH_COUNT 16 224 225#ifndef RPC_DEBUG 226# define RPC_WAITQ_INIT(var,qname) { \ 227 .lock = SPIN_LOCK_UNLOCKED, \ 228 .tasks = { \ 229 [0] = LIST_HEAD_INIT(var.tasks[0]), \ 230 [1] = LIST_HEAD_INIT(var.tasks[1]), \ 231 [2] = LIST_HEAD_INIT(var.tasks[2]), \ 232 }, \ 233 } 234#else 235# define RPC_WAITQ_INIT(var,qname) { \ 236 .lock = SPIN_LOCK_UNLOCKED, \ 237 .tasks = { \ 238 [0] = LIST_HEAD_INIT(var.tasks[0]), \ 239 [1] = LIST_HEAD_INIT(var.tasks[1]), \ 240 [2] = LIST_HEAD_INIT(var.tasks[2]), \ 241 }, \ 242 .name = qname, \ 243 } 244#endif 245# define RPC_WAITQ(var,qname) struct rpc_wait_queue var = RPC_WAITQ_INIT(var,qname) 246 247#define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0) 248 249/* 250 * Function prototypes 251 */ 252struct rpc_task *rpc_new_task(struct rpc_clnt *, int flags, 253 const struct rpc_call_ops *ops, void *data); 254struct rpc_task *rpc_run_task(struct rpc_clnt *clnt, int flags, 255 const struct rpc_call_ops *ops, void *data); 256struct rpc_task *rpc_new_child(struct rpc_clnt *, struct rpc_task *parent); 257void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt, 258 int flags, const struct rpc_call_ops *ops, 259 void *data); 260void rpc_release_task(struct rpc_task *); 261void rpc_exit_task(struct rpc_task *); 262void rpc_killall_tasks(struct rpc_clnt *); 263int rpc_execute(struct rpc_task *); 264void rpc_run_child(struct rpc_task *parent, struct rpc_task *child, 265 rpc_action action); 266void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *); 267void rpc_init_wait_queue(struct rpc_wait_queue *, const char *); 268void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *, 269 rpc_action action, rpc_action timer); 270void rpc_wake_up_task(struct rpc_task *); 271void rpc_wake_up(struct rpc_wait_queue *); 272struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *); 273void rpc_wake_up_status(struct rpc_wait_queue *, int); 274void rpc_delay(struct rpc_task *, unsigned long); 275void * rpc_malloc(struct rpc_task *, size_t); 276void rpc_free(struct rpc_task *); 277int rpciod_up(void); 278void rpciod_down(void); 279int __rpc_wait_for_completion_task(struct rpc_task *task, int (*)(void *)); 280#ifdef RPC_DEBUG 281void rpc_show_tasks(void); 282#endif 283int rpc_init_mempool(void); 284void rpc_destroy_mempool(void); 285extern struct workqueue_struct *rpciod_workqueue; 286 287static inline void rpc_exit(struct rpc_task *task, int status) 288{ 289 task->tk_status = status; 290 task->tk_action = rpc_exit_task; 291} 292 293static inline int rpc_wait_for_completion_task(struct rpc_task *task) 294{ 295 return __rpc_wait_for_completion_task(task, NULL); 296} 297 298#ifdef RPC_DEBUG 299static inline const char * rpc_qname(struct rpc_wait_queue *q) 300{ 301 return ((q && q->name) ? q->name : "unknown"); 302} 303#endif 304 305#endif /* _LINUX_SUNRPC_SCHED_H_ */ 306