Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/net/sunrpc/sched.c | |
3 | * | |
4 | * Scheduling for synchronous and asynchronous RPC requests. | |
5 | * | |
6 | * Copyright (C) 1996 Olaf Kirch, <okir@monad.swb.de> | |
cca5172a | 7 | * |
1da177e4 LT |
8 | * TCP NFS related read + write fixes |
9 | * (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie> | |
10 | */ | |
11 | ||
12 | #include <linux/module.h> | |
13 | ||
14 | #include <linux/sched.h> | |
15 | #include <linux/interrupt.h> | |
16 | #include <linux/slab.h> | |
17 | #include <linux/mempool.h> | |
18 | #include <linux/smp.h> | |
1da177e4 | 19 | #include <linux/spinlock.h> |
4a3e2f71 | 20 | #include <linux/mutex.h> |
d310310c | 21 | #include <linux/freezer.h> |
1da177e4 LT |
22 | |
23 | #include <linux/sunrpc/clnt.h> | |
1da177e4 | 24 | |
6951867b BH |
25 | #include "sunrpc.h" |
26 | ||
1da177e4 LT |
27 | #ifdef RPC_DEBUG |
28 | #define RPCDBG_FACILITY RPCDBG_SCHED | |
1da177e4 LT |
29 | #endif |
30 | ||
82b0a4c3 TM |
31 | #define CREATE_TRACE_POINTS |
32 | #include <trace/events/sunrpc.h> | |
33 | ||
1da177e4 LT |
34 | /* |
35 | * RPC slabs and memory pools | |
36 | */ | |
37 | #define RPC_BUFFER_MAXSIZE (2048) | |
38 | #define RPC_BUFFER_POOLSIZE (8) | |
39 | #define RPC_TASK_POOLSIZE (8) | |
e18b890b CL |
40 | static struct kmem_cache *rpc_task_slabp __read_mostly; |
41 | static struct kmem_cache *rpc_buffer_slabp __read_mostly; | |
ba89966c ED |
42 | static mempool_t *rpc_task_mempool __read_mostly; |
43 | static mempool_t *rpc_buffer_mempool __read_mostly; | |
1da177e4 | 44 | |
65f27f38 | 45 | static void rpc_async_schedule(struct work_struct *); |
bde8f00c | 46 | static void rpc_release_task(struct rpc_task *task); |
36df9aae | 47 | static void __rpc_queue_timer_fn(unsigned long ptr); |
1da177e4 | 48 | |
1da177e4 LT |
49 | /* |
50 | * RPC tasks sit here while waiting for conditions to improve. | |
51 | */ | |
a4a87499 | 52 | static struct rpc_wait_queue delay_queue; |
1da177e4 | 53 | |
1da177e4 LT |
54 | /* |
55 | * rpciod-related stuff | |
56 | */ | |
24c5d9d7 | 57 | struct workqueue_struct *rpciod_workqueue; |
1da177e4 | 58 | |
1da177e4 LT |
59 | /* |
60 | * Disable the timer for a given RPC task. Should be called with | |
61 | * queue->lock and bh_disabled in order to avoid races within | |
62 | * rpc_run_timer(). | |
63 | */ | |
5d00837b | 64 | static void |
eb276c0e | 65 | __rpc_disable_timer(struct rpc_wait_queue *queue, struct rpc_task *task) |
1da177e4 | 66 | { |
36df9aae TM |
67 | if (task->tk_timeout == 0) |
68 | return; | |
46121cf7 | 69 | dprintk("RPC: %5u disabling timer\n", task->tk_pid); |
1da177e4 | 70 | task->tk_timeout = 0; |
36df9aae | 71 | list_del(&task->u.tk_wait.timer_list); |
eb276c0e TM |
72 | if (list_empty(&queue->timer_list.list)) |
73 | del_timer(&queue->timer_list.timer); | |
36df9aae TM |
74 | } |
75 | ||
76 | static void | |
77 | rpc_set_queue_timer(struct rpc_wait_queue *queue, unsigned long expires) | |
78 | { | |
79 | queue->timer_list.expires = expires; | |
80 | mod_timer(&queue->timer_list.timer, expires); | |
1da177e4 LT |
81 | } |
82 | ||
1da177e4 LT |
83 | /* |
84 | * Set up a timer for the current task. | |
85 | */ | |
5d00837b | 86 | static void |
eb276c0e | 87 | __rpc_add_timer(struct rpc_wait_queue *queue, struct rpc_task *task) |
1da177e4 LT |
88 | { |
89 | if (!task->tk_timeout) | |
90 | return; | |
91 | ||
46121cf7 | 92 | dprintk("RPC: %5u setting alarm for %lu ms\n", |
1da177e4 LT |
93 | task->tk_pid, task->tk_timeout * 1000 / HZ); |
94 | ||
eb276c0e TM |
95 | task->u.tk_wait.expires = jiffies + task->tk_timeout; |
96 | if (list_empty(&queue->timer_list.list) || time_before(task->u.tk_wait.expires, queue->timer_list.expires)) | |
97 | rpc_set_queue_timer(queue, task->u.tk_wait.expires); | |
98 | list_add(&task->u.tk_wait.timer_list, &queue->timer_list.list); | |
1da177e4 LT |
99 | } |
100 | ||
101 | /* | |
102 | * Add new request to a priority queue. | |
103 | */ | |
3b27bad7 TM |
104 | static void __rpc_add_wait_queue_priority(struct rpc_wait_queue *queue, |
105 | struct rpc_task *task, | |
106 | unsigned char queue_priority) | |
1da177e4 LT |
107 | { |
108 | struct list_head *q; | |
109 | struct rpc_task *t; | |
110 | ||
111 | INIT_LIST_HEAD(&task->u.tk_wait.links); | |
3b27bad7 TM |
112 | q = &queue->tasks[queue_priority]; |
113 | if (unlikely(queue_priority > queue->maxpriority)) | |
1da177e4 LT |
114 | q = &queue->tasks[queue->maxpriority]; |
115 | list_for_each_entry(t, q, u.tk_wait.list) { | |
3ff7576d | 116 | if (t->tk_owner == task->tk_owner) { |
1da177e4 LT |
117 | list_add_tail(&task->u.tk_wait.list, &t->u.tk_wait.links); |
118 | return; | |
119 | } | |
120 | } | |
121 | list_add_tail(&task->u.tk_wait.list, q); | |
122 | } | |
123 | ||
124 | /* | |
125 | * Add new request to wait queue. | |
126 | * | |
127 | * Swapper tasks always get inserted at the head of the queue. | |
128 | * This should avoid many nasty memory deadlocks and hopefully | |
129 | * improve overall performance. | |
130 | * Everyone else gets appended to the queue to ensure proper FIFO behavior. | |
131 | */ | |
3b27bad7 TM |
132 | static void __rpc_add_wait_queue(struct rpc_wait_queue *queue, |
133 | struct rpc_task *task, | |
134 | unsigned char queue_priority) | |
1da177e4 | 135 | { |
2bd4eef8 WAA |
136 | WARN_ON_ONCE(RPC_IS_QUEUED(task)); |
137 | if (RPC_IS_QUEUED(task)) | |
138 | return; | |
1da177e4 LT |
139 | |
140 | if (RPC_IS_PRIORITY(queue)) | |
3b27bad7 | 141 | __rpc_add_wait_queue_priority(queue, task, queue_priority); |
1da177e4 LT |
142 | else if (RPC_IS_SWAPPER(task)) |
143 | list_add(&task->u.tk_wait.list, &queue->tasks[0]); | |
144 | else | |
145 | list_add_tail(&task->u.tk_wait.list, &queue->tasks[0]); | |
96ef13b2 | 146 | task->tk_waitqueue = queue; |
e19b63da | 147 | queue->qlen++; |
1da177e4 LT |
148 | rpc_set_queued(task); |
149 | ||
46121cf7 CL |
150 | dprintk("RPC: %5u added to queue %p \"%s\"\n", |
151 | task->tk_pid, queue, rpc_qname(queue)); | |
1da177e4 LT |
152 | } |
153 | ||
154 | /* | |
155 | * Remove request from a priority queue. | |
156 | */ | |
157 | static void __rpc_remove_wait_queue_priority(struct rpc_task *task) | |
158 | { | |
159 | struct rpc_task *t; | |
160 | ||
161 | if (!list_empty(&task->u.tk_wait.links)) { | |
162 | t = list_entry(task->u.tk_wait.links.next, struct rpc_task, u.tk_wait.list); | |
163 | list_move(&t->u.tk_wait.list, &task->u.tk_wait.list); | |
164 | list_splice_init(&task->u.tk_wait.links, &t->u.tk_wait.links); | |
165 | } | |
1da177e4 LT |
166 | } |
167 | ||
168 | /* | |
169 | * Remove request from queue. | |
170 | * Note: must be called with spin lock held. | |
171 | */ | |
96ef13b2 | 172 | static void __rpc_remove_wait_queue(struct rpc_wait_queue *queue, struct rpc_task *task) |
1da177e4 | 173 | { |
eb276c0e | 174 | __rpc_disable_timer(queue, task); |
1da177e4 LT |
175 | if (RPC_IS_PRIORITY(queue)) |
176 | __rpc_remove_wait_queue_priority(task); | |
36df9aae | 177 | list_del(&task->u.tk_wait.list); |
e19b63da | 178 | queue->qlen--; |
46121cf7 CL |
179 | dprintk("RPC: %5u removed from queue %p \"%s\"\n", |
180 | task->tk_pid, queue, rpc_qname(queue)); | |
1da177e4 LT |
181 | } |
182 | ||
183 | static inline void rpc_set_waitqueue_priority(struct rpc_wait_queue *queue, int priority) | |
184 | { | |
185 | queue->priority = priority; | |
186 | queue->count = 1 << (priority * 2); | |
187 | } | |
188 | ||
3ff7576d | 189 | static inline void rpc_set_waitqueue_owner(struct rpc_wait_queue *queue, pid_t pid) |
1da177e4 | 190 | { |
3ff7576d | 191 | queue->owner = pid; |
1da177e4 LT |
192 | queue->nr = RPC_BATCH_COUNT; |
193 | } | |
194 | ||
195 | static inline void rpc_reset_waitqueue_priority(struct rpc_wait_queue *queue) | |
196 | { | |
197 | rpc_set_waitqueue_priority(queue, queue->maxpriority); | |
3ff7576d | 198 | rpc_set_waitqueue_owner(queue, 0); |
1da177e4 LT |
199 | } |
200 | ||
3ff7576d | 201 | static void __rpc_init_priority_wait_queue(struct rpc_wait_queue *queue, const char *qname, unsigned char nr_queues) |
1da177e4 LT |
202 | { |
203 | int i; | |
204 | ||
205 | spin_lock_init(&queue->lock); | |
206 | for (i = 0; i < ARRAY_SIZE(queue->tasks); i++) | |
207 | INIT_LIST_HEAD(&queue->tasks[i]); | |
3ff7576d | 208 | queue->maxpriority = nr_queues - 1; |
1da177e4 | 209 | rpc_reset_waitqueue_priority(queue); |
36df9aae TM |
210 | queue->qlen = 0; |
211 | setup_timer(&queue->timer_list.timer, __rpc_queue_timer_fn, (unsigned long)queue); | |
212 | INIT_LIST_HEAD(&queue->timer_list.list); | |
2f09c242 | 213 | rpc_assign_waitqueue_name(queue, qname); |
1da177e4 LT |
214 | } |
215 | ||
216 | void rpc_init_priority_wait_queue(struct rpc_wait_queue *queue, const char *qname) | |
217 | { | |
3ff7576d | 218 | __rpc_init_priority_wait_queue(queue, qname, RPC_NR_PRIORITY); |
1da177e4 | 219 | } |
689cf5c1 | 220 | EXPORT_SYMBOL_GPL(rpc_init_priority_wait_queue); |
1da177e4 LT |
221 | |
222 | void rpc_init_wait_queue(struct rpc_wait_queue *queue, const char *qname) | |
223 | { | |
3ff7576d | 224 | __rpc_init_priority_wait_queue(queue, qname, 1); |
1da177e4 | 225 | } |
e8914c65 | 226 | EXPORT_SYMBOL_GPL(rpc_init_wait_queue); |
1da177e4 | 227 | |
f6a1cc89 TM |
228 | void rpc_destroy_wait_queue(struct rpc_wait_queue *queue) |
229 | { | |
36df9aae | 230 | del_timer_sync(&queue->timer_list.timer); |
f6a1cc89 TM |
231 | } |
232 | EXPORT_SYMBOL_GPL(rpc_destroy_wait_queue); | |
233 | ||
150030b7 | 234 | static int rpc_wait_bit_killable(void *word) |
44c28873 | 235 | { |
150030b7 | 236 | if (fatal_signal_pending(current)) |
44c28873 | 237 | return -ERESTARTSYS; |
d310310c | 238 | freezable_schedule(); |
44c28873 TM |
239 | return 0; |
240 | } | |
241 | ||
c44fe705 TM |
242 | #ifdef RPC_DEBUG |
243 | static void rpc_task_set_debuginfo(struct rpc_task *task) | |
244 | { | |
245 | static atomic_t rpc_pid; | |
246 | ||
c44fe705 TM |
247 | task->tk_pid = atomic_inc_return(&rpc_pid); |
248 | } | |
249 | #else | |
250 | static inline void rpc_task_set_debuginfo(struct rpc_task *task) | |
251 | { | |
252 | } | |
253 | #endif | |
254 | ||
e6b3c4db TM |
255 | static void rpc_set_active(struct rpc_task *task) |
256 | { | |
82b0a4c3 TM |
257 | trace_rpc_task_begin(task->tk_client, task, NULL); |
258 | ||
c44fe705 | 259 | rpc_task_set_debuginfo(task); |
58f9612c | 260 | set_bit(RPC_TASK_ACTIVE, &task->tk_runstate); |
e6b3c4db TM |
261 | } |
262 | ||
44c28873 TM |
263 | /* |
264 | * Mark an RPC call as having completed by clearing the 'active' bit | |
bf294b41 | 265 | * and then waking up all tasks that were sleeping. |
44c28873 | 266 | */ |
bf294b41 | 267 | static int rpc_complete_task(struct rpc_task *task) |
44c28873 | 268 | { |
bf294b41 TM |
269 | void *m = &task->tk_runstate; |
270 | wait_queue_head_t *wq = bit_waitqueue(m, RPC_TASK_ACTIVE); | |
271 | struct wait_bit_key k = __WAIT_BIT_KEY_INITIALIZER(m, RPC_TASK_ACTIVE); | |
272 | unsigned long flags; | |
273 | int ret; | |
274 | ||
82b0a4c3 TM |
275 | trace_rpc_task_complete(task->tk_client, task, NULL); |
276 | ||
bf294b41 | 277 | spin_lock_irqsave(&wq->lock, flags); |
e6b3c4db | 278 | clear_bit(RPC_TASK_ACTIVE, &task->tk_runstate); |
bf294b41 TM |
279 | ret = atomic_dec_and_test(&task->tk_count); |
280 | if (waitqueue_active(wq)) | |
281 | __wake_up_locked_key(wq, TASK_NORMAL, &k); | |
282 | spin_unlock_irqrestore(&wq->lock, flags); | |
283 | return ret; | |
44c28873 TM |
284 | } |
285 | ||
286 | /* | |
287 | * Allow callers to wait for completion of an RPC call | |
bf294b41 TM |
288 | * |
289 | * Note the use of out_of_line_wait_on_bit() rather than wait_on_bit() | |
290 | * to enforce taking of the wq->lock and hence avoid races with | |
291 | * rpc_complete_task(). | |
44c28873 TM |
292 | */ |
293 | int __rpc_wait_for_completion_task(struct rpc_task *task, int (*action)(void *)) | |
294 | { | |
295 | if (action == NULL) | |
150030b7 | 296 | action = rpc_wait_bit_killable; |
bf294b41 | 297 | return out_of_line_wait_on_bit(&task->tk_runstate, RPC_TASK_ACTIVE, |
150030b7 | 298 | action, TASK_KILLABLE); |
44c28873 | 299 | } |
e8914c65 | 300 | EXPORT_SYMBOL_GPL(__rpc_wait_for_completion_task); |
44c28873 | 301 | |
1da177e4 LT |
302 | /* |
303 | * Make an RPC task runnable. | |
304 | * | |
506026c3 JL |
305 | * Note: If the task is ASYNC, and is being made runnable after sitting on an |
306 | * rpc_wait_queue, this must be called with the queue spinlock held to protect | |
307 | * the wait queue operation. | |
1da177e4 LT |
308 | */ |
309 | static void rpc_make_runnable(struct rpc_task *task) | |
310 | { | |
1da177e4 | 311 | rpc_clear_queued(task); |
cc4dc59e CS |
312 | if (rpc_test_and_set_running(task)) |
313 | return; | |
1da177e4 | 314 | if (RPC_IS_ASYNC(task)) { |
65f27f38 | 315 | INIT_WORK(&task->u.tk_work, rpc_async_schedule); |
cee6a537 | 316 | queue_work(rpciod_workqueue, &task->u.tk_work); |
1da177e4 | 317 | } else |
96651ab3 | 318 | wake_up_bit(&task->tk_runstate, RPC_TASK_QUEUED); |
1da177e4 LT |
319 | } |
320 | ||
1da177e4 LT |
321 | /* |
322 | * Prepare for sleeping on a wait queue. | |
323 | * By always appending tasks to the list we ensure FIFO behavior. | |
324 | * NB: An RPC task will only receive interrupt-driven events as long | |
325 | * as it's on a wait queue. | |
326 | */ | |
3b27bad7 TM |
327 | static void __rpc_sleep_on_priority(struct rpc_wait_queue *q, |
328 | struct rpc_task *task, | |
329 | rpc_action action, | |
330 | unsigned char queue_priority) | |
1da177e4 | 331 | { |
46121cf7 CL |
332 | dprintk("RPC: %5u sleep_on(queue \"%s\" time %lu)\n", |
333 | task->tk_pid, rpc_qname(q), jiffies); | |
1da177e4 | 334 | |
82b0a4c3 TM |
335 | trace_rpc_task_sleep(task->tk_client, task, q); |
336 | ||
3b27bad7 | 337 | __rpc_add_wait_queue(q, task, queue_priority); |
1da177e4 | 338 | |
f50ad428 | 339 | WARN_ON_ONCE(task->tk_callback != NULL); |
1da177e4 | 340 | task->tk_callback = action; |
eb276c0e | 341 | __rpc_add_timer(q, task); |
1da177e4 LT |
342 | } |
343 | ||
344 | void rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task, | |
5d00837b | 345 | rpc_action action) |
1da177e4 | 346 | { |
58f9612c | 347 | /* We shouldn't ever put an inactive task to sleep */ |
e454a7a8 WAA |
348 | WARN_ON_ONCE(!RPC_IS_ACTIVATED(task)); |
349 | if (!RPC_IS_ACTIVATED(task)) { | |
350 | task->tk_status = -EIO; | |
351 | rpc_put_task_async(task); | |
352 | return; | |
353 | } | |
e6b3c4db | 354 | |
1da177e4 LT |
355 | /* |
356 | * Protect the queue operations. | |
357 | */ | |
358 | spin_lock_bh(&q->lock); | |
3b27bad7 | 359 | __rpc_sleep_on_priority(q, task, action, task->tk_priority); |
1da177e4 LT |
360 | spin_unlock_bh(&q->lock); |
361 | } | |
e8914c65 | 362 | EXPORT_SYMBOL_GPL(rpc_sleep_on); |
1da177e4 | 363 | |
3b27bad7 TM |
364 | void rpc_sleep_on_priority(struct rpc_wait_queue *q, struct rpc_task *task, |
365 | rpc_action action, int priority) | |
366 | { | |
367 | /* We shouldn't ever put an inactive task to sleep */ | |
e454a7a8 WAA |
368 | WARN_ON_ONCE(!RPC_IS_ACTIVATED(task)); |
369 | if (!RPC_IS_ACTIVATED(task)) { | |
370 | task->tk_status = -EIO; | |
371 | rpc_put_task_async(task); | |
372 | return; | |
373 | } | |
3b27bad7 TM |
374 | |
375 | /* | |
376 | * Protect the queue operations. | |
377 | */ | |
378 | spin_lock_bh(&q->lock); | |
379 | __rpc_sleep_on_priority(q, task, action, priority - RPC_PRIORITY_LOW); | |
380 | spin_unlock_bh(&q->lock); | |
381 | } | |
1e1093c7 | 382 | EXPORT_SYMBOL_GPL(rpc_sleep_on_priority); |
3b27bad7 | 383 | |
1da177e4 LT |
384 | /** |
385 | * __rpc_do_wake_up_task - wake up a single rpc_task | |
96ef13b2 | 386 | * @queue: wait queue |
1da177e4 LT |
387 | * @task: task to be woken up |
388 | * | |
389 | * Caller must hold queue->lock, and have cleared the task queued flag. | |
390 | */ | |
96ef13b2 | 391 | static void __rpc_do_wake_up_task(struct rpc_wait_queue *queue, struct rpc_task *task) |
1da177e4 | 392 | { |
46121cf7 CL |
393 | dprintk("RPC: %5u __rpc_wake_up_task (now %lu)\n", |
394 | task->tk_pid, jiffies); | |
1da177e4 | 395 | |
1da177e4 LT |
396 | /* Has the task been executed yet? If not, we cannot wake it up! */ |
397 | if (!RPC_IS_ACTIVATED(task)) { | |
398 | printk(KERN_ERR "RPC: Inactive task (%p) being woken up!\n", task); | |
399 | return; | |
400 | } | |
401 | ||
82b0a4c3 TM |
402 | trace_rpc_task_wakeup(task->tk_client, task, queue); |
403 | ||
96ef13b2 | 404 | __rpc_remove_wait_queue(queue, task); |
1da177e4 LT |
405 | |
406 | rpc_make_runnable(task); | |
407 | ||
46121cf7 | 408 | dprintk("RPC: __rpc_wake_up_task done\n"); |
1da177e4 LT |
409 | } |
410 | ||
411 | /* | |
96ef13b2 | 412 | * Wake up a queued task while the queue lock is being held |
1da177e4 | 413 | */ |
96ef13b2 | 414 | static void rpc_wake_up_task_queue_locked(struct rpc_wait_queue *queue, struct rpc_task *task) |
1da177e4 | 415 | { |
f5fb7b06 TM |
416 | if (RPC_IS_QUEUED(task) && task->tk_waitqueue == queue) |
417 | __rpc_do_wake_up_task(queue, task); | |
1da177e4 LT |
418 | } |
419 | ||
48f18612 AB |
420 | /* |
421 | * Tests whether rpc queue is empty | |
422 | */ | |
423 | int rpc_queue_empty(struct rpc_wait_queue *queue) | |
424 | { | |
425 | int res; | |
426 | ||
427 | spin_lock_bh(&queue->lock); | |
428 | res = queue->qlen; | |
429 | spin_unlock_bh(&queue->lock); | |
a02cec21 | 430 | return res == 0; |
48f18612 AB |
431 | } |
432 | EXPORT_SYMBOL_GPL(rpc_queue_empty); | |
433 | ||
1da177e4 | 434 | /* |
96ef13b2 | 435 | * Wake up a task on a specific queue |
1da177e4 | 436 | */ |
96ef13b2 | 437 | void rpc_wake_up_queued_task(struct rpc_wait_queue *queue, struct rpc_task *task) |
1da177e4 | 438 | { |
5e4424af | 439 | spin_lock_bh(&queue->lock); |
96ef13b2 | 440 | rpc_wake_up_task_queue_locked(queue, task); |
5e4424af | 441 | spin_unlock_bh(&queue->lock); |
1da177e4 | 442 | } |
96ef13b2 TM |
443 | EXPORT_SYMBOL_GPL(rpc_wake_up_queued_task); |
444 | ||
1da177e4 LT |
445 | /* |
446 | * Wake up the next task on a priority queue. | |
447 | */ | |
961a828d | 448 | static struct rpc_task *__rpc_find_next_queued_priority(struct rpc_wait_queue *queue) |
1da177e4 LT |
449 | { |
450 | struct list_head *q; | |
451 | struct rpc_task *task; | |
452 | ||
453 | /* | |
3ff7576d | 454 | * Service a batch of tasks from a single owner. |
1da177e4 LT |
455 | */ |
456 | q = &queue->tasks[queue->priority]; | |
457 | if (!list_empty(q)) { | |
458 | task = list_entry(q->next, struct rpc_task, u.tk_wait.list); | |
3ff7576d | 459 | if (queue->owner == task->tk_owner) { |
1da177e4 LT |
460 | if (--queue->nr) |
461 | goto out; | |
462 | list_move_tail(&task->u.tk_wait.list, q); | |
463 | } | |
464 | /* | |
465 | * Check if we need to switch queues. | |
466 | */ | |
467 | if (--queue->count) | |
3ff7576d | 468 | goto new_owner; |
1da177e4 LT |
469 | } |
470 | ||
471 | /* | |
472 | * Service the next queue. | |
473 | */ | |
474 | do { | |
475 | if (q == &queue->tasks[0]) | |
476 | q = &queue->tasks[queue->maxpriority]; | |
477 | else | |
478 | q = q - 1; | |
479 | if (!list_empty(q)) { | |
480 | task = list_entry(q->next, struct rpc_task, u.tk_wait.list); | |
481 | goto new_queue; | |
482 | } | |
483 | } while (q != &queue->tasks[queue->priority]); | |
484 | ||
485 | rpc_reset_waitqueue_priority(queue); | |
486 | return NULL; | |
487 | ||
488 | new_queue: | |
489 | rpc_set_waitqueue_priority(queue, (unsigned int)(q - &queue->tasks[0])); | |
3ff7576d TM |
490 | new_owner: |
491 | rpc_set_waitqueue_owner(queue, task->tk_owner); | |
1da177e4 | 492 | out: |
1da177e4 LT |
493 | return task; |
494 | } | |
495 | ||
961a828d TM |
496 | static struct rpc_task *__rpc_find_next_queued(struct rpc_wait_queue *queue) |
497 | { | |
498 | if (RPC_IS_PRIORITY(queue)) | |
499 | return __rpc_find_next_queued_priority(queue); | |
500 | if (!list_empty(&queue->tasks[0])) | |
501 | return list_first_entry(&queue->tasks[0], struct rpc_task, u.tk_wait.list); | |
502 | return NULL; | |
503 | } | |
504 | ||
1da177e4 | 505 | /* |
961a828d | 506 | * Wake up the first task on the wait queue. |
1da177e4 | 507 | */ |
961a828d TM |
508 | struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *queue, |
509 | bool (*func)(struct rpc_task *, void *), void *data) | |
1da177e4 LT |
510 | { |
511 | struct rpc_task *task = NULL; | |
512 | ||
961a828d | 513 | dprintk("RPC: wake_up_first(%p \"%s\")\n", |
46121cf7 | 514 | queue, rpc_qname(queue)); |
5e4424af | 515 | spin_lock_bh(&queue->lock); |
961a828d TM |
516 | task = __rpc_find_next_queued(queue); |
517 | if (task != NULL) { | |
518 | if (func(task, data)) | |
96ef13b2 | 519 | rpc_wake_up_task_queue_locked(queue, task); |
961a828d TM |
520 | else |
521 | task = NULL; | |
1da177e4 | 522 | } |
5e4424af | 523 | spin_unlock_bh(&queue->lock); |
1da177e4 LT |
524 | |
525 | return task; | |
526 | } | |
961a828d TM |
527 | EXPORT_SYMBOL_GPL(rpc_wake_up_first); |
528 | ||
529 | static bool rpc_wake_up_next_func(struct rpc_task *task, void *data) | |
530 | { | |
531 | return true; | |
532 | } | |
533 | ||
534 | /* | |
535 | * Wake up the next task on the wait queue. | |
536 | */ | |
537 | struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *queue) | |
538 | { | |
539 | return rpc_wake_up_first(queue, rpc_wake_up_next_func, NULL); | |
540 | } | |
e8914c65 | 541 | EXPORT_SYMBOL_GPL(rpc_wake_up_next); |
1da177e4 LT |
542 | |
543 | /** | |
544 | * rpc_wake_up - wake up all rpc_tasks | |
545 | * @queue: rpc_wait_queue on which the tasks are sleeping | |
546 | * | |
547 | * Grabs queue->lock | |
548 | */ | |
549 | void rpc_wake_up(struct rpc_wait_queue *queue) | |
550 | { | |
1da177e4 | 551 | struct list_head *head; |
e6d83d55 | 552 | |
5e4424af | 553 | spin_lock_bh(&queue->lock); |
1da177e4 LT |
554 | head = &queue->tasks[queue->maxpriority]; |
555 | for (;;) { | |
540a0f75 TM |
556 | while (!list_empty(head)) { |
557 | struct rpc_task *task; | |
558 | task = list_first_entry(head, | |
559 | struct rpc_task, | |
560 | u.tk_wait.list); | |
96ef13b2 | 561 | rpc_wake_up_task_queue_locked(queue, task); |
540a0f75 | 562 | } |
1da177e4 LT |
563 | if (head == &queue->tasks[0]) |
564 | break; | |
565 | head--; | |
566 | } | |
5e4424af | 567 | spin_unlock_bh(&queue->lock); |
1da177e4 | 568 | } |
e8914c65 | 569 | EXPORT_SYMBOL_GPL(rpc_wake_up); |
1da177e4 LT |
570 | |
571 | /** | |
572 | * rpc_wake_up_status - wake up all rpc_tasks and set their status value. | |
573 | * @queue: rpc_wait_queue on which the tasks are sleeping | |
574 | * @status: status value to set | |
575 | * | |
576 | * Grabs queue->lock | |
577 | */ | |
578 | void rpc_wake_up_status(struct rpc_wait_queue *queue, int status) | |
579 | { | |
580 | struct list_head *head; | |
1da177e4 | 581 | |
5e4424af | 582 | spin_lock_bh(&queue->lock); |
1da177e4 LT |
583 | head = &queue->tasks[queue->maxpriority]; |
584 | for (;;) { | |
540a0f75 TM |
585 | while (!list_empty(head)) { |
586 | struct rpc_task *task; | |
587 | task = list_first_entry(head, | |
588 | struct rpc_task, | |
589 | u.tk_wait.list); | |
1da177e4 | 590 | task->tk_status = status; |
96ef13b2 | 591 | rpc_wake_up_task_queue_locked(queue, task); |
1da177e4 LT |
592 | } |
593 | if (head == &queue->tasks[0]) | |
594 | break; | |
595 | head--; | |
596 | } | |
5e4424af | 597 | spin_unlock_bh(&queue->lock); |
1da177e4 | 598 | } |
e8914c65 | 599 | EXPORT_SYMBOL_GPL(rpc_wake_up_status); |
1da177e4 | 600 | |
36df9aae TM |
601 | static void __rpc_queue_timer_fn(unsigned long ptr) |
602 | { | |
603 | struct rpc_wait_queue *queue = (struct rpc_wait_queue *)ptr; | |
604 | struct rpc_task *task, *n; | |
605 | unsigned long expires, now, timeo; | |
606 | ||
607 | spin_lock(&queue->lock); | |
608 | expires = now = jiffies; | |
609 | list_for_each_entry_safe(task, n, &queue->timer_list.list, u.tk_wait.timer_list) { | |
610 | timeo = task->u.tk_wait.expires; | |
611 | if (time_after_eq(now, timeo)) { | |
36df9aae TM |
612 | dprintk("RPC: %5u timeout\n", task->tk_pid); |
613 | task->tk_status = -ETIMEDOUT; | |
614 | rpc_wake_up_task_queue_locked(queue, task); | |
615 | continue; | |
616 | } | |
617 | if (expires == now || time_after(expires, timeo)) | |
618 | expires = timeo; | |
619 | } | |
620 | if (!list_empty(&queue->timer_list.list)) | |
621 | rpc_set_queue_timer(queue, expires); | |
622 | spin_unlock(&queue->lock); | |
623 | } | |
624 | ||
8014793b TM |
625 | static void __rpc_atrun(struct rpc_task *task) |
626 | { | |
5d00837b | 627 | task->tk_status = 0; |
8014793b TM |
628 | } |
629 | ||
1da177e4 LT |
630 | /* |
631 | * Run a task at a later time | |
632 | */ | |
8014793b | 633 | void rpc_delay(struct rpc_task *task, unsigned long delay) |
1da177e4 LT |
634 | { |
635 | task->tk_timeout = delay; | |
5d00837b | 636 | rpc_sleep_on(&delay_queue, task, __rpc_atrun); |
1da177e4 | 637 | } |
e8914c65 | 638 | EXPORT_SYMBOL_GPL(rpc_delay); |
1da177e4 | 639 | |
4ce70ada TM |
640 | /* |
641 | * Helper to call task->tk_ops->rpc_call_prepare | |
642 | */ | |
aae2006e | 643 | void rpc_prepare_task(struct rpc_task *task) |
4ce70ada TM |
644 | { |
645 | task->tk_ops->rpc_call_prepare(task, task->tk_calldata); | |
646 | } | |
647 | ||
7fdcf13b TM |
648 | static void |
649 | rpc_init_task_statistics(struct rpc_task *task) | |
650 | { | |
651 | /* Initialize retry counters */ | |
652 | task->tk_garb_retry = 2; | |
653 | task->tk_cred_retry = 2; | |
654 | task->tk_rebind_retry = 2; | |
655 | ||
656 | /* starting timestamp */ | |
657 | task->tk_start = ktime_get(); | |
658 | } | |
659 | ||
660 | static void | |
661 | rpc_reset_task_statistics(struct rpc_task *task) | |
662 | { | |
663 | task->tk_timeouts = 0; | |
664 | task->tk_flags &= ~(RPC_CALL_MAJORSEEN|RPC_TASK_KILLED|RPC_TASK_SENT); | |
665 | ||
666 | rpc_init_task_statistics(task); | |
667 | } | |
668 | ||
d05fdb0c | 669 | /* |
963d8fe5 | 670 | * Helper that calls task->tk_ops->rpc_call_done if it exists |
d05fdb0c | 671 | */ |
abbcf28f | 672 | void rpc_exit_task(struct rpc_task *task) |
d05fdb0c | 673 | { |
abbcf28f | 674 | task->tk_action = NULL; |
963d8fe5 TM |
675 | if (task->tk_ops->rpc_call_done != NULL) { |
676 | task->tk_ops->rpc_call_done(task, task->tk_calldata); | |
d05fdb0c | 677 | if (task->tk_action != NULL) { |
abbcf28f TM |
678 | WARN_ON(RPC_ASSASSINATED(task)); |
679 | /* Always release the RPC slot and buffer memory */ | |
680 | xprt_release(task); | |
7fdcf13b | 681 | rpc_reset_task_statistics(task); |
d05fdb0c TM |
682 | } |
683 | } | |
d05fdb0c | 684 | } |
d9b6cd94 TM |
685 | |
686 | void rpc_exit(struct rpc_task *task, int status) | |
687 | { | |
688 | task->tk_status = status; | |
689 | task->tk_action = rpc_exit_task; | |
690 | if (RPC_IS_QUEUED(task)) | |
691 | rpc_wake_up_queued_task(task->tk_waitqueue, task); | |
692 | } | |
693 | EXPORT_SYMBOL_GPL(rpc_exit); | |
d05fdb0c | 694 | |
bbd5a1f9 TM |
695 | void rpc_release_calldata(const struct rpc_call_ops *ops, void *calldata) |
696 | { | |
a86dc496 | 697 | if (ops->rpc_release != NULL) |
bbd5a1f9 | 698 | ops->rpc_release(calldata); |
bbd5a1f9 TM |
699 | } |
700 | ||
1da177e4 LT |
701 | /* |
702 | * This is the RPC `scheduler' (or rather, the finite state machine). | |
703 | */ | |
2efef837 | 704 | static void __rpc_execute(struct rpc_task *task) |
1da177e4 | 705 | { |
eb9b55ab TM |
706 | struct rpc_wait_queue *queue; |
707 | int task_is_async = RPC_IS_ASYNC(task); | |
708 | int status = 0; | |
1da177e4 | 709 | |
46121cf7 CL |
710 | dprintk("RPC: %5u __rpc_execute flags=0x%x\n", |
711 | task->tk_pid, task->tk_flags); | |
1da177e4 | 712 | |
2bd4eef8 WAA |
713 | WARN_ON_ONCE(RPC_IS_QUEUED(task)); |
714 | if (RPC_IS_QUEUED(task)) | |
715 | return; | |
1da177e4 | 716 | |
d05fdb0c | 717 | for (;;) { |
b55c5989 | 718 | void (*do_action)(struct rpc_task *); |
1da177e4 LT |
719 | |
720 | /* | |
b55c5989 | 721 | * Execute any pending callback first. |
1da177e4 | 722 | */ |
b55c5989 TM |
723 | do_action = task->tk_callback; |
724 | task->tk_callback = NULL; | |
725 | if (do_action == NULL) { | |
e020c680 TM |
726 | /* |
727 | * Perform the next FSM step. | |
b55c5989 TM |
728 | * tk_action may be NULL if the task has been killed. |
729 | * In particular, note that rpc_killall_tasks may | |
730 | * do this at any time, so beware when dereferencing. | |
e020c680 | 731 | */ |
b55c5989 TM |
732 | do_action = task->tk_action; |
733 | if (do_action == NULL) | |
1da177e4 | 734 | break; |
1da177e4 | 735 | } |
82b0a4c3 | 736 | trace_rpc_task_run_action(task->tk_client, task, task->tk_action); |
b55c5989 | 737 | do_action(task); |
1da177e4 LT |
738 | |
739 | /* | |
740 | * Lockless check for whether task is sleeping or not. | |
741 | */ | |
742 | if (!RPC_IS_QUEUED(task)) | |
743 | continue; | |
eb9b55ab TM |
744 | /* |
745 | * The queue->lock protects against races with | |
746 | * rpc_make_runnable(). | |
747 | * | |
748 | * Note that once we clear RPC_TASK_RUNNING on an asynchronous | |
749 | * rpc_task, rpc_make_runnable() can assign it to a | |
750 | * different workqueue. We therefore cannot assume that the | |
751 | * rpc_task pointer may still be dereferenced. | |
752 | */ | |
753 | queue = task->tk_waitqueue; | |
754 | spin_lock_bh(&queue->lock); | |
755 | if (!RPC_IS_QUEUED(task)) { | |
756 | spin_unlock_bh(&queue->lock); | |
1da177e4 LT |
757 | continue; |
758 | } | |
eb9b55ab TM |
759 | rpc_clear_running(task); |
760 | spin_unlock_bh(&queue->lock); | |
761 | if (task_is_async) | |
762 | return; | |
1da177e4 LT |
763 | |
764 | /* sync task: sleep here */ | |
46121cf7 | 765 | dprintk("RPC: %5u sync task going to sleep\n", task->tk_pid); |
96651ab3 | 766 | status = out_of_line_wait_on_bit(&task->tk_runstate, |
150030b7 MW |
767 | RPC_TASK_QUEUED, rpc_wait_bit_killable, |
768 | TASK_KILLABLE); | |
96651ab3 | 769 | if (status == -ERESTARTSYS) { |
1da177e4 LT |
770 | /* |
771 | * When a sync task receives a signal, it exits with | |
772 | * -ERESTARTSYS. In order to catch any callbacks that | |
773 | * clean up after sleeping on some queue, we don't | |
774 | * break the loop here, but go around once more. | |
775 | */ | |
46121cf7 | 776 | dprintk("RPC: %5u got signal\n", task->tk_pid); |
96651ab3 TM |
777 | task->tk_flags |= RPC_TASK_KILLED; |
778 | rpc_exit(task, -ERESTARTSYS); | |
1da177e4 LT |
779 | } |
780 | rpc_set_running(task); | |
46121cf7 | 781 | dprintk("RPC: %5u sync task resuming\n", task->tk_pid); |
1da177e4 LT |
782 | } |
783 | ||
46121cf7 CL |
784 | dprintk("RPC: %5u return %d, status %d\n", task->tk_pid, status, |
785 | task->tk_status); | |
1da177e4 LT |
786 | /* Release all resources associated with the task */ |
787 | rpc_release_task(task); | |
1da177e4 LT |
788 | } |
789 | ||
790 | /* | |
791 | * User-visible entry point to the scheduler. | |
792 | * | |
793 | * This may be called recursively if e.g. an async NFS task updates | |
794 | * the attributes and finds that dirty pages must be flushed. | |
795 | * NOTE: Upon exit of this function the task is guaranteed to be | |
796 | * released. In particular note that tk_release() will have | |
797 | * been called, so your task memory may have been freed. | |
798 | */ | |
2efef837 | 799 | void rpc_execute(struct rpc_task *task) |
1da177e4 | 800 | { |
44c28873 | 801 | rpc_set_active(task); |
d6a1ed08 TM |
802 | rpc_make_runnable(task); |
803 | if (!RPC_IS_ASYNC(task)) | |
804 | __rpc_execute(task); | |
1da177e4 LT |
805 | } |
806 | ||
65f27f38 | 807 | static void rpc_async_schedule(struct work_struct *work) |
1da177e4 | 808 | { |
5cf02d09 | 809 | current->flags |= PF_FSTRANS; |
65f27f38 | 810 | __rpc_execute(container_of(work, struct rpc_task, u.tk_work)); |
5cf02d09 | 811 | current->flags &= ~PF_FSTRANS; |
1da177e4 LT |
812 | } |
813 | ||
02107148 CL |
814 | /** |
815 | * rpc_malloc - allocate an RPC buffer | |
816 | * @task: RPC task that will use this buffer | |
817 | * @size: requested byte size | |
1da177e4 | 818 | * |
c5a4dd8b CL |
819 | * To prevent rpciod from hanging, this allocator never sleeps, |
820 | * returning NULL if the request cannot be serviced immediately. | |
821 | * The caller can arrange to sleep in a way that is safe for rpciod. | |
822 | * | |
823 | * Most requests are 'small' (under 2KiB) and can be serviced from a | |
824 | * mempool, ensuring that NFS reads and writes can always proceed, | |
825 | * and that there is good locality of reference for these buffers. | |
826 | * | |
1da177e4 | 827 | * In order to avoid memory starvation triggering more writebacks of |
c5a4dd8b | 828 | * NFS requests, we avoid using GFP_KERNEL. |
1da177e4 | 829 | */ |
c5a4dd8b | 830 | void *rpc_malloc(struct rpc_task *task, size_t size) |
1da177e4 | 831 | { |
aa3d1fae | 832 | struct rpc_buffer *buf; |
a564b8f0 MG |
833 | gfp_t gfp = GFP_NOWAIT; |
834 | ||
835 | if (RPC_IS_SWAPPER(task)) | |
836 | gfp |= __GFP_MEMALLOC; | |
1da177e4 | 837 | |
aa3d1fae | 838 | size += sizeof(struct rpc_buffer); |
c5a4dd8b CL |
839 | if (size <= RPC_BUFFER_MAXSIZE) |
840 | buf = mempool_alloc(rpc_buffer_mempool, gfp); | |
1da177e4 | 841 | else |
c5a4dd8b | 842 | buf = kmalloc(size, gfp); |
ddce40df PZ |
843 | |
844 | if (!buf) | |
845 | return NULL; | |
846 | ||
aa3d1fae | 847 | buf->len = size; |
215d0678 | 848 | dprintk("RPC: %5u allocated buffer of size %zu at %p\n", |
c5a4dd8b | 849 | task->tk_pid, size, buf); |
aa3d1fae | 850 | return &buf->data; |
1da177e4 | 851 | } |
12444809 | 852 | EXPORT_SYMBOL_GPL(rpc_malloc); |
1da177e4 | 853 | |
02107148 CL |
854 | /** |
855 | * rpc_free - free buffer allocated via rpc_malloc | |
c5a4dd8b | 856 | * @buffer: buffer to free |
02107148 CL |
857 | * |
858 | */ | |
c5a4dd8b | 859 | void rpc_free(void *buffer) |
1da177e4 | 860 | { |
aa3d1fae CL |
861 | size_t size; |
862 | struct rpc_buffer *buf; | |
02107148 | 863 | |
c5a4dd8b CL |
864 | if (!buffer) |
865 | return; | |
aa3d1fae CL |
866 | |
867 | buf = container_of(buffer, struct rpc_buffer, data); | |
868 | size = buf->len; | |
c5a4dd8b | 869 | |
215d0678 | 870 | dprintk("RPC: freeing buffer of size %zu at %p\n", |
c5a4dd8b | 871 | size, buf); |
aa3d1fae | 872 | |
c5a4dd8b CL |
873 | if (size <= RPC_BUFFER_MAXSIZE) |
874 | mempool_free(buf, rpc_buffer_mempool); | |
875 | else | |
876 | kfree(buf); | |
1da177e4 | 877 | } |
12444809 | 878 | EXPORT_SYMBOL_GPL(rpc_free); |
1da177e4 LT |
879 | |
880 | /* | |
881 | * Creation and deletion of RPC task structures | |
882 | */ | |
47fe0648 | 883 | static void rpc_init_task(struct rpc_task *task, const struct rpc_task_setup *task_setup_data) |
1da177e4 LT |
884 | { |
885 | memset(task, 0, sizeof(*task)); | |
44c28873 | 886 | atomic_set(&task->tk_count, 1); |
84115e1c TM |
887 | task->tk_flags = task_setup_data->flags; |
888 | task->tk_ops = task_setup_data->callback_ops; | |
889 | task->tk_calldata = task_setup_data->callback_data; | |
6529eba0 | 890 | INIT_LIST_HEAD(&task->tk_task); |
1da177e4 | 891 | |
3ff7576d TM |
892 | task->tk_priority = task_setup_data->priority - RPC_PRIORITY_LOW; |
893 | task->tk_owner = current->tgid; | |
1da177e4 LT |
894 | |
895 | /* Initialize workqueue for async tasks */ | |
32bfb5c0 | 896 | task->tk_workqueue = task_setup_data->workqueue; |
1da177e4 | 897 | |
84115e1c TM |
898 | if (task->tk_ops->rpc_call_prepare != NULL) |
899 | task->tk_action = rpc_prepare_task; | |
963d8fe5 | 900 | |
7fdcf13b | 901 | rpc_init_task_statistics(task); |
ef759a2e | 902 | |
46121cf7 | 903 | dprintk("RPC: new task initialized, procpid %u\n", |
ba25f9dc | 904 | task_pid_nr(current)); |
1da177e4 LT |
905 | } |
906 | ||
907 | static struct rpc_task * | |
908 | rpc_alloc_task(void) | |
909 | { | |
a564b8f0 | 910 | return (struct rpc_task *)mempool_alloc(rpc_task_mempool, GFP_NOIO); |
1da177e4 LT |
911 | } |
912 | ||
1da177e4 | 913 | /* |
90c5755f | 914 | * Create a new task for the specified client. |
1da177e4 | 915 | */ |
84115e1c | 916 | struct rpc_task *rpc_new_task(const struct rpc_task_setup *setup_data) |
1da177e4 | 917 | { |
e8f5d77c TM |
918 | struct rpc_task *task = setup_data->task; |
919 | unsigned short flags = 0; | |
920 | ||
921 | if (task == NULL) { | |
922 | task = rpc_alloc_task(); | |
19445b99 TM |
923 | if (task == NULL) { |
924 | rpc_release_calldata(setup_data->callback_ops, | |
925 | setup_data->callback_data); | |
926 | return ERR_PTR(-ENOMEM); | |
927 | } | |
e8f5d77c TM |
928 | flags = RPC_TASK_DYNAMIC; |
929 | } | |
1da177e4 | 930 | |
84115e1c | 931 | rpc_init_task(task, setup_data); |
e8f5d77c | 932 | task->tk_flags |= flags; |
46121cf7 | 933 | dprintk("RPC: allocated task %p\n", task); |
1da177e4 | 934 | return task; |
1da177e4 LT |
935 | } |
936 | ||
32bfb5c0 | 937 | static void rpc_free_task(struct rpc_task *task) |
1da177e4 | 938 | { |
963d8fe5 TM |
939 | const struct rpc_call_ops *tk_ops = task->tk_ops; |
940 | void *calldata = task->tk_calldata; | |
1da177e4 | 941 | |
5e4424af TM |
942 | if (task->tk_flags & RPC_TASK_DYNAMIC) { |
943 | dprintk("RPC: %5u freeing task\n", task->tk_pid); | |
944 | mempool_free(task, rpc_task_mempool); | |
945 | } | |
32bfb5c0 TM |
946 | rpc_release_calldata(tk_ops, calldata); |
947 | } | |
948 | ||
949 | static void rpc_async_release(struct work_struct *work) | |
950 | { | |
951 | rpc_free_task(container_of(work, struct rpc_task, u.tk_work)); | |
952 | } | |
953 | ||
bf294b41 | 954 | static void rpc_release_resources_task(struct rpc_task *task) |
32bfb5c0 | 955 | { |
e6b3c4db TM |
956 | if (task->tk_rqstp) |
957 | xprt_release(task); | |
a271c5a0 | 958 | if (task->tk_msg.rpc_cred) { |
a17c2153 | 959 | put_rpccred(task->tk_msg.rpc_cred); |
a271c5a0 OH |
960 | task->tk_msg.rpc_cred = NULL; |
961 | } | |
58f9612c | 962 | rpc_task_release_client(task); |
bf294b41 TM |
963 | } |
964 | ||
965 | static void rpc_final_put_task(struct rpc_task *task, | |
966 | struct workqueue_struct *q) | |
967 | { | |
968 | if (q != NULL) { | |
32bfb5c0 | 969 | INIT_WORK(&task->u.tk_work, rpc_async_release); |
bf294b41 | 970 | queue_work(q, &task->u.tk_work); |
32bfb5c0 TM |
971 | } else |
972 | rpc_free_task(task); | |
e6b3c4db | 973 | } |
bf294b41 TM |
974 | |
975 | static void rpc_do_put_task(struct rpc_task *task, struct workqueue_struct *q) | |
976 | { | |
977 | if (atomic_dec_and_test(&task->tk_count)) { | |
978 | rpc_release_resources_task(task); | |
979 | rpc_final_put_task(task, q); | |
980 | } | |
981 | } | |
982 | ||
983 | void rpc_put_task(struct rpc_task *task) | |
984 | { | |
985 | rpc_do_put_task(task, NULL); | |
986 | } | |
e8914c65 | 987 | EXPORT_SYMBOL_GPL(rpc_put_task); |
e6b3c4db | 988 | |
bf294b41 TM |
989 | void rpc_put_task_async(struct rpc_task *task) |
990 | { | |
991 | rpc_do_put_task(task, task->tk_workqueue); | |
992 | } | |
993 | EXPORT_SYMBOL_GPL(rpc_put_task_async); | |
994 | ||
bde8f00c | 995 | static void rpc_release_task(struct rpc_task *task) |
e6b3c4db | 996 | { |
46121cf7 | 997 | dprintk("RPC: %5u release task\n", task->tk_pid); |
1da177e4 | 998 | |
0a0c2a57 | 999 | WARN_ON_ONCE(RPC_IS_QUEUED(task)); |
1da177e4 | 1000 | |
bf294b41 | 1001 | rpc_release_resources_task(task); |
e6b3c4db | 1002 | |
bf294b41 TM |
1003 | /* |
1004 | * Note: at this point we have been removed from rpc_clnt->cl_tasks, | |
1005 | * so it should be safe to use task->tk_count as a test for whether | |
1006 | * or not any other processes still hold references to our rpc_task. | |
1007 | */ | |
1008 | if (atomic_read(&task->tk_count) != 1 + !RPC_IS_ASYNC(task)) { | |
1009 | /* Wake up anyone who may be waiting for task completion */ | |
1010 | if (!rpc_complete_task(task)) | |
1011 | return; | |
1012 | } else { | |
1013 | if (!atomic_dec_and_test(&task->tk_count)) | |
1014 | return; | |
1015 | } | |
1016 | rpc_final_put_task(task, task->tk_workqueue); | |
1da177e4 LT |
1017 | } |
1018 | ||
b247bbf1 TM |
1019 | int rpciod_up(void) |
1020 | { | |
1021 | return try_module_get(THIS_MODULE) ? 0 : -EINVAL; | |
1022 | } | |
1023 | ||
1024 | void rpciod_down(void) | |
1025 | { | |
1026 | module_put(THIS_MODULE); | |
1027 | } | |
1028 | ||
1da177e4 | 1029 | /* |
b247bbf1 | 1030 | * Start up the rpciod workqueue. |
1da177e4 | 1031 | */ |
b247bbf1 | 1032 | static int rpciod_start(void) |
1da177e4 LT |
1033 | { |
1034 | struct workqueue_struct *wq; | |
ab418d70 | 1035 | |
1da177e4 LT |
1036 | /* |
1037 | * Create the rpciod thread and wait for it to start. | |
1038 | */ | |
ab418d70 | 1039 | dprintk("RPC: creating workqueue rpciod\n"); |
9b96ce71 | 1040 | wq = alloc_workqueue("rpciod", WQ_MEM_RECLAIM, 1); |
1da177e4 | 1041 | rpciod_workqueue = wq; |
b247bbf1 | 1042 | return rpciod_workqueue != NULL; |
1da177e4 LT |
1043 | } |
1044 | ||
b247bbf1 | 1045 | static void rpciod_stop(void) |
1da177e4 | 1046 | { |
b247bbf1 | 1047 | struct workqueue_struct *wq = NULL; |
ab418d70 | 1048 | |
b247bbf1 TM |
1049 | if (rpciod_workqueue == NULL) |
1050 | return; | |
ab418d70 | 1051 | dprintk("RPC: destroying workqueue rpciod\n"); |
1da177e4 | 1052 | |
b247bbf1 TM |
1053 | wq = rpciod_workqueue; |
1054 | rpciod_workqueue = NULL; | |
1055 | destroy_workqueue(wq); | |
1da177e4 LT |
1056 | } |
1057 | ||
1da177e4 LT |
1058 | void |
1059 | rpc_destroy_mempool(void) | |
1060 | { | |
b247bbf1 | 1061 | rpciod_stop(); |
1da177e4 LT |
1062 | if (rpc_buffer_mempool) |
1063 | mempool_destroy(rpc_buffer_mempool); | |
1064 | if (rpc_task_mempool) | |
1065 | mempool_destroy(rpc_task_mempool); | |
1a1d92c1 AD |
1066 | if (rpc_task_slabp) |
1067 | kmem_cache_destroy(rpc_task_slabp); | |
1068 | if (rpc_buffer_slabp) | |
1069 | kmem_cache_destroy(rpc_buffer_slabp); | |
f6a1cc89 | 1070 | rpc_destroy_wait_queue(&delay_queue); |
1da177e4 LT |
1071 | } |
1072 | ||
1073 | int | |
1074 | rpc_init_mempool(void) | |
1075 | { | |
f6a1cc89 TM |
1076 | /* |
1077 | * The following is not strictly a mempool initialisation, | |
1078 | * but there is no harm in doing it here | |
1079 | */ | |
1080 | rpc_init_wait_queue(&delay_queue, "delayq"); | |
1081 | if (!rpciod_start()) | |
1082 | goto err_nomem; | |
1083 | ||
1da177e4 LT |
1084 | rpc_task_slabp = kmem_cache_create("rpc_tasks", |
1085 | sizeof(struct rpc_task), | |
1086 | 0, SLAB_HWCACHE_ALIGN, | |
20c2df83 | 1087 | NULL); |
1da177e4 LT |
1088 | if (!rpc_task_slabp) |
1089 | goto err_nomem; | |
1090 | rpc_buffer_slabp = kmem_cache_create("rpc_buffers", | |
1091 | RPC_BUFFER_MAXSIZE, | |
1092 | 0, SLAB_HWCACHE_ALIGN, | |
20c2df83 | 1093 | NULL); |
1da177e4 LT |
1094 | if (!rpc_buffer_slabp) |
1095 | goto err_nomem; | |
93d2341c MD |
1096 | rpc_task_mempool = mempool_create_slab_pool(RPC_TASK_POOLSIZE, |
1097 | rpc_task_slabp); | |
1da177e4 LT |
1098 | if (!rpc_task_mempool) |
1099 | goto err_nomem; | |
93d2341c MD |
1100 | rpc_buffer_mempool = mempool_create_slab_pool(RPC_BUFFER_POOLSIZE, |
1101 | rpc_buffer_slabp); | |
1da177e4 LT |
1102 | if (!rpc_buffer_mempool) |
1103 | goto err_nomem; | |
1104 | return 0; | |
1105 | err_nomem: | |
1106 | rpc_destroy_mempool(); | |
1107 | return -ENOMEM; | |
1108 | } |