2 * linux/net/sunrpc/sched.c
4 * Scheduling for synchronous and asynchronous RPC requests.
6 * Copyright (C) 1996 Olaf Kirch, <okir@monad.swb.de>
8 * TCP NFS related read + write fixes
9 * (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
12 #include <linux/module.h>
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>
19 #include <linux/smp_lock.h>
20 #include <linux/spinlock.h>
21 #include <linux/mutex.h>
23 #include <linux/sunrpc/clnt.h>
26 #define RPCDBG_FACILITY RPCDBG_SCHED
27 #define RPC_TASK_MAGIC_ID 0xf00baa
31 * RPC slabs and memory pools
33 #define RPC_BUFFER_MAXSIZE (2048)
34 #define RPC_BUFFER_POOLSIZE (8)
35 #define RPC_TASK_POOLSIZE (8)
36 static struct kmem_cache *rpc_task_slabp __read_mostly;
37 static struct kmem_cache *rpc_buffer_slabp __read_mostly;
38 static mempool_t *rpc_task_mempool __read_mostly;
39 static mempool_t *rpc_buffer_mempool __read_mostly;
41 static void rpc_async_schedule(struct work_struct *);
42 static void rpc_release_task(struct rpc_task *task);
45 * RPC tasks sit here while waiting for conditions to improve.
47 static struct rpc_wait_queue delay_queue;
50 * rpciod-related stuff
52 struct workqueue_struct *rpciod_workqueue;
55 * Disable the timer for a given RPC task. Should be called with
56 * queue->lock and bh_disabled in order to avoid races within
60 __rpc_disable_timer(struct rpc_task *task)
62 dprintk("RPC: %5u disabling timer\n", task->tk_pid);
67 * Set up a timer for the current task.
70 __rpc_add_timer(struct rpc_task *task)
72 if (!task->tk_timeout)
75 dprintk("RPC: %5u setting alarm for %lu ms\n",
76 task->tk_pid, task->tk_timeout * 1000 / HZ);
78 set_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate);
79 mod_timer(&task->tk_timer, jiffies + task->tk_timeout);
83 * Delete any timer for the current task. Because we use del_timer_sync(),
84 * this function should never be called while holding queue->lock.
87 rpc_delete_timer(struct rpc_task *task)
89 if (RPC_IS_QUEUED(task))
91 if (test_and_clear_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate)) {
92 del_singleshot_timer_sync(&task->tk_timer);
93 dprintk("RPC: %5u deleting timer\n", task->tk_pid);
98 * Add new request to a priority queue.
100 static void __rpc_add_wait_queue_priority(struct rpc_wait_queue *queue, struct rpc_task *task)
105 INIT_LIST_HEAD(&task->u.tk_wait.links);
106 q = &queue->tasks[task->tk_priority];
107 if (unlikely(task->tk_priority > queue->maxpriority))
108 q = &queue->tasks[queue->maxpriority];
109 list_for_each_entry(t, q, u.tk_wait.list) {
110 if (t->tk_owner == task->tk_owner) {
111 list_add_tail(&task->u.tk_wait.list, &t->u.tk_wait.links);
115 list_add_tail(&task->u.tk_wait.list, q);
119 * Add new request to wait queue.
121 * Swapper tasks always get inserted at the head of the queue.
122 * This should avoid many nasty memory deadlocks and hopefully
123 * improve overall performance.
124 * Everyone else gets appended to the queue to ensure proper FIFO behavior.
126 static void __rpc_add_wait_queue(struct rpc_wait_queue *queue, struct rpc_task *task)
128 BUG_ON (RPC_IS_QUEUED(task));
130 if (RPC_IS_PRIORITY(queue))
131 __rpc_add_wait_queue_priority(queue, task);
132 else if (RPC_IS_SWAPPER(task))
133 list_add(&task->u.tk_wait.list, &queue->tasks[0]);
135 list_add_tail(&task->u.tk_wait.list, &queue->tasks[0]);
136 task->tk_waitqueue = queue;
138 rpc_set_queued(task);
140 dprintk("RPC: %5u added to queue %p \"%s\"\n",
141 task->tk_pid, queue, rpc_qname(queue));
145 * Remove request from a priority queue.
147 static void __rpc_remove_wait_queue_priority(struct rpc_task *task)
151 if (!list_empty(&task->u.tk_wait.links)) {
152 t = list_entry(task->u.tk_wait.links.next, struct rpc_task, u.tk_wait.list);
153 list_move(&t->u.tk_wait.list, &task->u.tk_wait.list);
154 list_splice_init(&task->u.tk_wait.links, &t->u.tk_wait.links);
156 list_del(&task->u.tk_wait.list);
160 * Remove request from queue.
161 * Note: must be called with spin lock held.
163 static void __rpc_remove_wait_queue(struct rpc_wait_queue *queue, struct rpc_task *task)
165 if (RPC_IS_PRIORITY(queue))
166 __rpc_remove_wait_queue_priority(task);
168 list_del(&task->u.tk_wait.list);
170 dprintk("RPC: %5u removed from queue %p \"%s\"\n",
171 task->tk_pid, queue, rpc_qname(queue));
174 static inline void rpc_set_waitqueue_priority(struct rpc_wait_queue *queue, int priority)
176 queue->priority = priority;
177 queue->count = 1 << (priority * 2);
180 static inline void rpc_set_waitqueue_owner(struct rpc_wait_queue *queue, pid_t pid)
183 queue->nr = RPC_BATCH_COUNT;
186 static inline void rpc_reset_waitqueue_priority(struct rpc_wait_queue *queue)
188 rpc_set_waitqueue_priority(queue, queue->maxpriority);
189 rpc_set_waitqueue_owner(queue, 0);
192 static void __rpc_init_priority_wait_queue(struct rpc_wait_queue *queue, const char *qname, unsigned char nr_queues)
196 spin_lock_init(&queue->lock);
197 for (i = 0; i < ARRAY_SIZE(queue->tasks); i++)
198 INIT_LIST_HEAD(&queue->tasks[i]);
199 queue->maxpriority = nr_queues - 1;
200 rpc_reset_waitqueue_priority(queue);
206 void rpc_init_priority_wait_queue(struct rpc_wait_queue *queue, const char *qname)
208 __rpc_init_priority_wait_queue(queue, qname, RPC_NR_PRIORITY);
211 void rpc_init_wait_queue(struct rpc_wait_queue *queue, const char *qname)
213 __rpc_init_priority_wait_queue(queue, qname, 1);
215 EXPORT_SYMBOL_GPL(rpc_init_wait_queue);
217 void rpc_destroy_wait_queue(struct rpc_wait_queue *queue)
220 EXPORT_SYMBOL_GPL(rpc_destroy_wait_queue);
222 static int rpc_wait_bit_killable(void *word)
224 if (fatal_signal_pending(current))
231 static void rpc_task_set_debuginfo(struct rpc_task *task)
233 static atomic_t rpc_pid;
235 task->tk_magic = RPC_TASK_MAGIC_ID;
236 task->tk_pid = atomic_inc_return(&rpc_pid);
239 static inline void rpc_task_set_debuginfo(struct rpc_task *task)
244 static void rpc_set_active(struct rpc_task *task)
246 struct rpc_clnt *clnt;
247 if (test_and_set_bit(RPC_TASK_ACTIVE, &task->tk_runstate) != 0)
249 rpc_task_set_debuginfo(task);
250 /* Add to global list of all tasks */
251 clnt = task->tk_client;
253 spin_lock(&clnt->cl_lock);
254 list_add_tail(&task->tk_task, &clnt->cl_tasks);
255 spin_unlock(&clnt->cl_lock);
260 * Mark an RPC call as having completed by clearing the 'active' bit
262 static void rpc_mark_complete_task(struct rpc_task *task)
264 smp_mb__before_clear_bit();
265 clear_bit(RPC_TASK_ACTIVE, &task->tk_runstate);
266 smp_mb__after_clear_bit();
267 wake_up_bit(&task->tk_runstate, RPC_TASK_ACTIVE);
271 * Allow callers to wait for completion of an RPC call
273 int __rpc_wait_for_completion_task(struct rpc_task *task, int (*action)(void *))
276 action = rpc_wait_bit_killable;
277 return wait_on_bit(&task->tk_runstate, RPC_TASK_ACTIVE,
278 action, TASK_KILLABLE);
280 EXPORT_SYMBOL_GPL(__rpc_wait_for_completion_task);
283 * Make an RPC task runnable.
285 * Note: If the task is ASYNC, this must be called with
286 * the spinlock held to protect the wait queue operation.
288 static void rpc_make_runnable(struct rpc_task *task)
290 rpc_clear_queued(task);
291 if (rpc_test_and_set_running(task))
293 /* We might have raced */
294 if (RPC_IS_QUEUED(task)) {
295 rpc_clear_running(task);
298 if (RPC_IS_ASYNC(task)) {
301 INIT_WORK(&task->u.tk_work, rpc_async_schedule);
302 status = queue_work(rpciod_workqueue, &task->u.tk_work);
304 printk(KERN_WARNING "RPC: failed to add task to queue: error: %d!\n", status);
305 task->tk_status = status;
309 wake_up_bit(&task->tk_runstate, RPC_TASK_QUEUED);
313 * Prepare for sleeping on a wait queue.
314 * By always appending tasks to the list we ensure FIFO behavior.
315 * NB: An RPC task will only receive interrupt-driven events as long
316 * as it's on a wait queue.
318 static void __rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
321 dprintk("RPC: %5u sleep_on(queue \"%s\" time %lu)\n",
322 task->tk_pid, rpc_qname(q), jiffies);
324 if (!RPC_IS_ASYNC(task) && !RPC_IS_ACTIVATED(task)) {
325 printk(KERN_ERR "RPC: Inactive synchronous task put to sleep!\n");
329 __rpc_add_wait_queue(q, task);
331 BUG_ON(task->tk_callback != NULL);
332 task->tk_callback = action;
333 __rpc_add_timer(task);
336 void rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
339 /* Mark the task as being activated if so needed */
340 rpc_set_active(task);
343 * Protect the queue operations.
345 spin_lock_bh(&q->lock);
346 __rpc_sleep_on(q, task, action);
347 spin_unlock_bh(&q->lock);
349 EXPORT_SYMBOL_GPL(rpc_sleep_on);
352 * __rpc_do_wake_up_task - wake up a single rpc_task
354 * @task: task to be woken up
356 * Caller must hold queue->lock, and have cleared the task queued flag.
358 static void __rpc_do_wake_up_task(struct rpc_wait_queue *queue, struct rpc_task *task)
360 dprintk("RPC: %5u __rpc_wake_up_task (now %lu)\n",
361 task->tk_pid, jiffies);
364 BUG_ON(task->tk_magic != RPC_TASK_MAGIC_ID);
366 /* Has the task been executed yet? If not, we cannot wake it up! */
367 if (!RPC_IS_ACTIVATED(task)) {
368 printk(KERN_ERR "RPC: Inactive task (%p) being woken up!\n", task);
372 __rpc_disable_timer(task);
373 __rpc_remove_wait_queue(queue, task);
375 rpc_make_runnable(task);
377 dprintk("RPC: __rpc_wake_up_task done\n");
381 * Wake up a queued task while the queue lock is being held
383 static void rpc_wake_up_task_queue_locked(struct rpc_wait_queue *queue, struct rpc_task *task)
385 if (!RPC_IS_QUEUED(task) || task->tk_waitqueue != queue)
387 if (rpc_start_wakeup(task)) {
388 __rpc_do_wake_up_task(queue, task);
389 rpc_finish_wakeup(task);
394 * Wake up a task on a specific queue
396 void rpc_wake_up_queued_task(struct rpc_wait_queue *queue, struct rpc_task *task)
399 spin_lock(&queue->lock);
400 rpc_wake_up_task_queue_locked(queue, task);
401 spin_unlock(&queue->lock);
402 rcu_read_unlock_bh();
404 EXPORT_SYMBOL_GPL(rpc_wake_up_queued_task);
407 * Wake up the specified task
409 static void rpc_wake_up_task(struct rpc_task *task)
411 rpc_wake_up_queued_task(task->tk_waitqueue, task);
415 * Wake up the next task on a priority queue.
417 static struct rpc_task * __rpc_wake_up_next_priority(struct rpc_wait_queue *queue)
420 struct rpc_task *task;
423 * Service a batch of tasks from a single owner.
425 q = &queue->tasks[queue->priority];
426 if (!list_empty(q)) {
427 task = list_entry(q->next, struct rpc_task, u.tk_wait.list);
428 if (queue->owner == task->tk_owner) {
431 list_move_tail(&task->u.tk_wait.list, q);
434 * Check if we need to switch queues.
441 * Service the next queue.
444 if (q == &queue->tasks[0])
445 q = &queue->tasks[queue->maxpriority];
448 if (!list_empty(q)) {
449 task = list_entry(q->next, struct rpc_task, u.tk_wait.list);
452 } while (q != &queue->tasks[queue->priority]);
454 rpc_reset_waitqueue_priority(queue);
458 rpc_set_waitqueue_priority(queue, (unsigned int)(q - &queue->tasks[0]));
460 rpc_set_waitqueue_owner(queue, task->tk_owner);
462 rpc_wake_up_task_queue_locked(queue, task);
467 * Wake up the next task on the wait queue.
469 struct rpc_task * rpc_wake_up_next(struct rpc_wait_queue *queue)
471 struct rpc_task *task = NULL;
473 dprintk("RPC: wake_up_next(%p \"%s\")\n",
474 queue, rpc_qname(queue));
476 spin_lock(&queue->lock);
477 if (RPC_IS_PRIORITY(queue))
478 task = __rpc_wake_up_next_priority(queue);
480 task_for_first(task, &queue->tasks[0])
481 rpc_wake_up_task_queue_locked(queue, task);
483 spin_unlock(&queue->lock);
484 rcu_read_unlock_bh();
488 EXPORT_SYMBOL_GPL(rpc_wake_up_next);
491 * rpc_wake_up - wake up all rpc_tasks
492 * @queue: rpc_wait_queue on which the tasks are sleeping
496 void rpc_wake_up(struct rpc_wait_queue *queue)
498 struct rpc_task *task, *next;
499 struct list_head *head;
502 spin_lock(&queue->lock);
503 head = &queue->tasks[queue->maxpriority];
505 list_for_each_entry_safe(task, next, head, u.tk_wait.list)
506 rpc_wake_up_task_queue_locked(queue, task);
507 if (head == &queue->tasks[0])
511 spin_unlock(&queue->lock);
512 rcu_read_unlock_bh();
514 EXPORT_SYMBOL_GPL(rpc_wake_up);
517 * rpc_wake_up_status - wake up all rpc_tasks and set their status value.
518 * @queue: rpc_wait_queue on which the tasks are sleeping
519 * @status: status value to set
523 void rpc_wake_up_status(struct rpc_wait_queue *queue, int status)
525 struct rpc_task *task, *next;
526 struct list_head *head;
529 spin_lock(&queue->lock);
530 head = &queue->tasks[queue->maxpriority];
532 list_for_each_entry_safe(task, next, head, u.tk_wait.list) {
533 task->tk_status = status;
534 rpc_wake_up_task_queue_locked(queue, task);
536 if (head == &queue->tasks[0])
540 spin_unlock(&queue->lock);
541 rcu_read_unlock_bh();
543 EXPORT_SYMBOL_GPL(rpc_wake_up_status);
546 * Run a timeout function.
548 static void rpc_run_timer(unsigned long ptr)
550 struct rpc_task *task = (struct rpc_task *)ptr;
551 struct rpc_wait_queue *queue = task->tk_waitqueue;
553 spin_lock(&queue->lock);
554 if (RPC_IS_QUEUED(task) && task->tk_waitqueue == queue) {
555 dprintk("RPC: %5u timeout\n", task->tk_pid);
556 task->tk_status = -ETIMEDOUT;
557 rpc_wake_up_task_queue_locked(queue, task);
559 spin_unlock(&queue->lock);
560 smp_mb__before_clear_bit();
561 clear_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate);
562 smp_mb__after_clear_bit();
565 static void __rpc_atrun(struct rpc_task *task)
571 * Run a task at a later time
573 void rpc_delay(struct rpc_task *task, unsigned long delay)
575 task->tk_timeout = delay;
576 rpc_sleep_on(&delay_queue, task, __rpc_atrun);
578 EXPORT_SYMBOL_GPL(rpc_delay);
581 * Helper to call task->tk_ops->rpc_call_prepare
583 static void rpc_prepare_task(struct rpc_task *task)
586 task->tk_ops->rpc_call_prepare(task, task->tk_calldata);
591 * Helper that calls task->tk_ops->rpc_call_done if it exists
593 void rpc_exit_task(struct rpc_task *task)
595 task->tk_action = NULL;
596 if (task->tk_ops->rpc_call_done != NULL) {
598 task->tk_ops->rpc_call_done(task, task->tk_calldata);
600 if (task->tk_action != NULL) {
601 WARN_ON(RPC_ASSASSINATED(task));
602 /* Always release the RPC slot and buffer memory */
607 EXPORT_SYMBOL_GPL(rpc_exit_task);
609 void rpc_release_calldata(const struct rpc_call_ops *ops, void *calldata)
611 if (ops->rpc_release != NULL) {
613 ops->rpc_release(calldata);
619 * This is the RPC `scheduler' (or rather, the finite state machine).
621 static void __rpc_execute(struct rpc_task *task)
625 dprintk("RPC: %5u __rpc_execute flags=0x%x\n",
626 task->tk_pid, task->tk_flags);
628 BUG_ON(RPC_IS_QUEUED(task));
632 * Garbage collection of pending timers...
634 rpc_delete_timer(task);
637 * Execute any pending callback.
639 if (RPC_DO_CALLBACK(task)) {
640 /* Define a callback save pointer */
641 void (*save_callback)(struct rpc_task *);
644 * If a callback exists, save it, reset it,
646 * The save is needed to stop from resetting
647 * another callback set within the callback handler
650 save_callback=task->tk_callback;
651 task->tk_callback=NULL;
656 * Perform the next FSM step.
657 * tk_action may be NULL when the task has been killed
660 if (!RPC_IS_QUEUED(task)) {
661 if (task->tk_action == NULL)
663 task->tk_action(task);
667 * Lockless check for whether task is sleeping or not.
669 if (!RPC_IS_QUEUED(task))
671 rpc_clear_running(task);
672 if (RPC_IS_ASYNC(task)) {
673 /* Careful! we may have raced... */
674 if (RPC_IS_QUEUED(task))
676 if (rpc_test_and_set_running(task))
681 /* sync task: sleep here */
682 dprintk("RPC: %5u sync task going to sleep\n", task->tk_pid);
683 status = out_of_line_wait_on_bit(&task->tk_runstate,
684 RPC_TASK_QUEUED, rpc_wait_bit_killable,
686 if (status == -ERESTARTSYS) {
688 * When a sync task receives a signal, it exits with
689 * -ERESTARTSYS. In order to catch any callbacks that
690 * clean up after sleeping on some queue, we don't
691 * break the loop here, but go around once more.
693 dprintk("RPC: %5u got signal\n", task->tk_pid);
694 task->tk_flags |= RPC_TASK_KILLED;
695 rpc_exit(task, -ERESTARTSYS);
696 rpc_wake_up_task(task);
698 rpc_set_running(task);
699 dprintk("RPC: %5u sync task resuming\n", task->tk_pid);
702 dprintk("RPC: %5u return %d, status %d\n", task->tk_pid, status,
704 /* Release all resources associated with the task */
705 rpc_release_task(task);
709 * User-visible entry point to the scheduler.
711 * This may be called recursively if e.g. an async NFS task updates
712 * the attributes and finds that dirty pages must be flushed.
713 * NOTE: Upon exit of this function the task is guaranteed to be
714 * released. In particular note that tk_release() will have
715 * been called, so your task memory may have been freed.
717 void rpc_execute(struct rpc_task *task)
719 rpc_set_active(task);
720 rpc_set_running(task);
724 static void rpc_async_schedule(struct work_struct *work)
726 __rpc_execute(container_of(work, struct rpc_task, u.tk_work));
735 * rpc_malloc - allocate an RPC buffer
736 * @task: RPC task that will use this buffer
737 * @size: requested byte size
739 * To prevent rpciod from hanging, this allocator never sleeps,
740 * returning NULL if the request cannot be serviced immediately.
741 * The caller can arrange to sleep in a way that is safe for rpciod.
743 * Most requests are 'small' (under 2KiB) and can be serviced from a
744 * mempool, ensuring that NFS reads and writes can always proceed,
745 * and that there is good locality of reference for these buffers.
747 * In order to avoid memory starvation triggering more writebacks of
748 * NFS requests, we avoid using GFP_KERNEL.
750 void *rpc_malloc(struct rpc_task *task, size_t size)
752 struct rpc_buffer *buf;
753 gfp_t gfp = RPC_IS_SWAPPER(task) ? GFP_ATOMIC : GFP_NOWAIT;
755 size += sizeof(struct rpc_buffer);
756 if (size <= RPC_BUFFER_MAXSIZE)
757 buf = mempool_alloc(rpc_buffer_mempool, gfp);
759 buf = kmalloc(size, gfp);
765 dprintk("RPC: %5u allocated buffer of size %zu at %p\n",
766 task->tk_pid, size, buf);
769 EXPORT_SYMBOL_GPL(rpc_malloc);
772 * rpc_free - free buffer allocated via rpc_malloc
773 * @buffer: buffer to free
776 void rpc_free(void *buffer)
779 struct rpc_buffer *buf;
784 buf = container_of(buffer, struct rpc_buffer, data);
787 dprintk("RPC: freeing buffer of size %zu at %p\n",
790 if (size <= RPC_BUFFER_MAXSIZE)
791 mempool_free(buf, rpc_buffer_mempool);
795 EXPORT_SYMBOL_GPL(rpc_free);
798 * Creation and deletion of RPC task structures
800 static void rpc_init_task(struct rpc_task *task, const struct rpc_task_setup *task_setup_data)
802 memset(task, 0, sizeof(*task));
803 setup_timer(&task->tk_timer, rpc_run_timer, (unsigned long)task);
804 atomic_set(&task->tk_count, 1);
805 task->tk_flags = task_setup_data->flags;
806 task->tk_ops = task_setup_data->callback_ops;
807 task->tk_calldata = task_setup_data->callback_data;
808 INIT_LIST_HEAD(&task->tk_task);
810 /* Initialize retry counters */
811 task->tk_garb_retry = 2;
812 task->tk_cred_retry = 2;
814 task->tk_priority = task_setup_data->priority - RPC_PRIORITY_LOW;
815 task->tk_owner = current->tgid;
817 /* Initialize workqueue for async tasks */
818 task->tk_workqueue = task_setup_data->workqueue;
820 task->tk_client = task_setup_data->rpc_client;
821 if (task->tk_client != NULL) {
822 kref_get(&task->tk_client->cl_kref);
823 if (task->tk_client->cl_softrtry)
824 task->tk_flags |= RPC_TASK_SOFT;
827 if (task->tk_ops->rpc_call_prepare != NULL)
828 task->tk_action = rpc_prepare_task;
830 if (task_setup_data->rpc_message != NULL) {
831 memcpy(&task->tk_msg, task_setup_data->rpc_message, sizeof(task->tk_msg));
832 /* Bind the user cred */
833 if (task->tk_msg.rpc_cred != NULL)
834 rpcauth_holdcred(task);
836 rpcauth_bindcred(task);
837 if (task->tk_action == NULL)
838 rpc_call_start(task);
841 /* starting timestamp */
842 task->tk_start = jiffies;
844 dprintk("RPC: new task initialized, procpid %u\n",
845 task_pid_nr(current));
848 static struct rpc_task *
851 return (struct rpc_task *)mempool_alloc(rpc_task_mempool, GFP_NOFS);
854 static void rpc_free_task_rcu(struct rcu_head *rcu)
856 struct rpc_task *task = container_of(rcu, struct rpc_task, u.tk_rcu);
857 dprintk("RPC: %5u freeing task\n", task->tk_pid);
858 mempool_free(task, rpc_task_mempool);
862 * Create a new task for the specified client.
864 struct rpc_task *rpc_new_task(const struct rpc_task_setup *setup_data)
866 struct rpc_task *task = setup_data->task;
867 unsigned short flags = 0;
870 task = rpc_alloc_task();
873 flags = RPC_TASK_DYNAMIC;
876 rpc_init_task(task, setup_data);
878 task->tk_flags |= flags;
879 dprintk("RPC: allocated task %p\n", task);
884 static void rpc_free_task(struct rpc_task *task)
886 const struct rpc_call_ops *tk_ops = task->tk_ops;
887 void *calldata = task->tk_calldata;
889 if (task->tk_flags & RPC_TASK_DYNAMIC)
890 call_rcu_bh(&task->u.tk_rcu, rpc_free_task_rcu);
891 rpc_release_calldata(tk_ops, calldata);
894 static void rpc_async_release(struct work_struct *work)
896 rpc_free_task(container_of(work, struct rpc_task, u.tk_work));
899 void rpc_put_task(struct rpc_task *task)
901 if (!atomic_dec_and_test(&task->tk_count))
903 /* Release resources */
906 if (task->tk_msg.rpc_cred)
907 rpcauth_unbindcred(task);
908 if (task->tk_client) {
909 rpc_release_client(task->tk_client);
910 task->tk_client = NULL;
912 if (task->tk_workqueue != NULL) {
913 INIT_WORK(&task->u.tk_work, rpc_async_release);
914 queue_work(task->tk_workqueue, &task->u.tk_work);
918 EXPORT_SYMBOL_GPL(rpc_put_task);
920 static void rpc_release_task(struct rpc_task *task)
923 BUG_ON(task->tk_magic != RPC_TASK_MAGIC_ID);
925 dprintk("RPC: %5u release task\n", task->tk_pid);
927 if (!list_empty(&task->tk_task)) {
928 struct rpc_clnt *clnt = task->tk_client;
929 /* Remove from client task list */
930 spin_lock(&clnt->cl_lock);
931 list_del(&task->tk_task);
932 spin_unlock(&clnt->cl_lock);
934 BUG_ON (RPC_IS_QUEUED(task));
936 /* Synchronously delete any running timer */
937 rpc_delete_timer(task);
942 /* Wake up anyone who is waiting for task completion */
943 rpc_mark_complete_task(task);
949 * Kill all tasks for the given client.
950 * XXX: kill their descendants as well?
952 void rpc_killall_tasks(struct rpc_clnt *clnt)
954 struct rpc_task *rovr;
957 if (list_empty(&clnt->cl_tasks))
959 dprintk("RPC: killing all tasks for client %p\n", clnt);
961 * Spin lock all_tasks to prevent changes...
963 spin_lock(&clnt->cl_lock);
964 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
965 if (! RPC_IS_ACTIVATED(rovr))
967 if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
968 rovr->tk_flags |= RPC_TASK_KILLED;
969 rpc_exit(rovr, -EIO);
970 rpc_wake_up_task(rovr);
973 spin_unlock(&clnt->cl_lock);
975 EXPORT_SYMBOL_GPL(rpc_killall_tasks);
979 return try_module_get(THIS_MODULE) ? 0 : -EINVAL;
982 void rpciod_down(void)
984 module_put(THIS_MODULE);
988 * Start up the rpciod workqueue.
990 static int rpciod_start(void)
992 struct workqueue_struct *wq;
995 * Create the rpciod thread and wait for it to start.
997 dprintk("RPC: creating workqueue rpciod\n");
998 wq = create_workqueue("rpciod");
999 rpciod_workqueue = wq;
1000 return rpciod_workqueue != NULL;
1003 static void rpciod_stop(void)
1005 struct workqueue_struct *wq = NULL;
1007 if (rpciod_workqueue == NULL)
1009 dprintk("RPC: destroying workqueue rpciod\n");
1011 wq = rpciod_workqueue;
1012 rpciod_workqueue = NULL;
1013 destroy_workqueue(wq);
1017 rpc_destroy_mempool(void)
1020 if (rpc_buffer_mempool)
1021 mempool_destroy(rpc_buffer_mempool);
1022 if (rpc_task_mempool)
1023 mempool_destroy(rpc_task_mempool);
1025 kmem_cache_destroy(rpc_task_slabp);
1026 if (rpc_buffer_slabp)
1027 kmem_cache_destroy(rpc_buffer_slabp);
1028 rpc_destroy_wait_queue(&delay_queue);
1032 rpc_init_mempool(void)
1035 * The following is not strictly a mempool initialisation,
1036 * but there is no harm in doing it here
1038 rpc_init_wait_queue(&delay_queue, "delayq");
1039 if (!rpciod_start())
1042 rpc_task_slabp = kmem_cache_create("rpc_tasks",
1043 sizeof(struct rpc_task),
1044 0, SLAB_HWCACHE_ALIGN,
1046 if (!rpc_task_slabp)
1048 rpc_buffer_slabp = kmem_cache_create("rpc_buffers",
1050 0, SLAB_HWCACHE_ALIGN,
1052 if (!rpc_buffer_slabp)
1054 rpc_task_mempool = mempool_create_slab_pool(RPC_TASK_POOLSIZE,
1056 if (!rpc_task_mempool)
1058 rpc_buffer_mempool = mempool_create_slab_pool(RPC_BUFFER_POOLSIZE,
1060 if (!rpc_buffer_mempool)
1064 rpc_destroy_mempool();