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
28 static int rpc_task_id;
32 * RPC slabs and memory pools
34 #define RPC_BUFFER_MAXSIZE (2048)
35 #define RPC_BUFFER_POOLSIZE (8)
36 #define RPC_TASK_POOLSIZE (8)
37 static struct kmem_cache *rpc_task_slabp __read_mostly;
38 static struct kmem_cache *rpc_buffer_slabp __read_mostly;
39 static mempool_t *rpc_task_mempool __read_mostly;
40 static mempool_t *rpc_buffer_mempool __read_mostly;
42 static void __rpc_default_timer(struct rpc_task *task);
43 static void rpciod_killall(void);
44 static void rpc_async_schedule(struct work_struct *);
45 static void rpc_release_task(struct rpc_task *task);
48 * RPC tasks sit here while waiting for conditions to improve.
50 static RPC_WAITQ(delay_queue, "delayq");
53 * All RPC clients are linked into this list
55 static LIST_HEAD(all_clients);
56 static DECLARE_WAIT_QUEUE_HEAD(client_kill_wait);
59 * rpciod-related stuff
61 static DEFINE_MUTEX(rpciod_mutex);
62 static unsigned int rpciod_users;
63 struct workqueue_struct *rpciod_workqueue;
66 * Spinlock for other critical sections of code.
68 static DEFINE_SPINLOCK(rpc_sched_lock);
71 * Disable the timer for a given RPC task. Should be called with
72 * queue->lock and bh_disabled in order to avoid races within
76 __rpc_disable_timer(struct rpc_task *task)
78 dprintk("RPC: %5u disabling timer\n", task->tk_pid);
79 task->tk_timeout_fn = NULL;
84 * Run a timeout function.
85 * We use the callback in order to allow __rpc_wake_up_task()
86 * and friends to disable the timer synchronously on SMP systems
87 * without calling del_timer_sync(). The latter could cause a
88 * deadlock if called while we're holding spinlocks...
90 static void rpc_run_timer(struct rpc_task *task)
92 void (*callback)(struct rpc_task *);
94 callback = task->tk_timeout_fn;
95 task->tk_timeout_fn = NULL;
96 if (callback && RPC_IS_QUEUED(task)) {
97 dprintk("RPC: %5u running timer\n", task->tk_pid);
100 smp_mb__before_clear_bit();
101 clear_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate);
102 smp_mb__after_clear_bit();
106 * Set up a timer for the current task.
109 __rpc_add_timer(struct rpc_task *task, rpc_action timer)
111 if (!task->tk_timeout)
114 dprintk("RPC: %5u setting alarm for %lu ms\n",
115 task->tk_pid, task->tk_timeout * 1000 / HZ);
118 task->tk_timeout_fn = timer;
120 task->tk_timeout_fn = __rpc_default_timer;
121 set_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate);
122 mod_timer(&task->tk_timer, jiffies + task->tk_timeout);
126 * Delete any timer for the current task. Because we use del_timer_sync(),
127 * this function should never be called while holding queue->lock.
130 rpc_delete_timer(struct rpc_task *task)
132 if (RPC_IS_QUEUED(task))
134 if (test_and_clear_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate)) {
135 del_singleshot_timer_sync(&task->tk_timer);
136 dprintk("RPC: %5u deleting timer\n", task->tk_pid);
141 * Add new request to a priority queue.
143 static void __rpc_add_wait_queue_priority(struct rpc_wait_queue *queue, struct rpc_task *task)
148 INIT_LIST_HEAD(&task->u.tk_wait.links);
149 q = &queue->tasks[task->tk_priority];
150 if (unlikely(task->tk_priority > queue->maxpriority))
151 q = &queue->tasks[queue->maxpriority];
152 list_for_each_entry(t, q, u.tk_wait.list) {
153 if (t->tk_cookie == task->tk_cookie) {
154 list_add_tail(&task->u.tk_wait.list, &t->u.tk_wait.links);
158 list_add_tail(&task->u.tk_wait.list, q);
162 * Add new request to wait queue.
164 * Swapper tasks always get inserted at the head of the queue.
165 * This should avoid many nasty memory deadlocks and hopefully
166 * improve overall performance.
167 * Everyone else gets appended to the queue to ensure proper FIFO behavior.
169 static void __rpc_add_wait_queue(struct rpc_wait_queue *queue, struct rpc_task *task)
171 BUG_ON (RPC_IS_QUEUED(task));
173 if (RPC_IS_PRIORITY(queue))
174 __rpc_add_wait_queue_priority(queue, task);
175 else if (RPC_IS_SWAPPER(task))
176 list_add(&task->u.tk_wait.list, &queue->tasks[0]);
178 list_add_tail(&task->u.tk_wait.list, &queue->tasks[0]);
179 task->u.tk_wait.rpc_waitq = queue;
181 rpc_set_queued(task);
183 dprintk("RPC: %5u added to queue %p \"%s\"\n",
184 task->tk_pid, queue, rpc_qname(queue));
188 * Remove request from a priority queue.
190 static void __rpc_remove_wait_queue_priority(struct rpc_task *task)
194 if (!list_empty(&task->u.tk_wait.links)) {
195 t = list_entry(task->u.tk_wait.links.next, struct rpc_task, u.tk_wait.list);
196 list_move(&t->u.tk_wait.list, &task->u.tk_wait.list);
197 list_splice_init(&task->u.tk_wait.links, &t->u.tk_wait.links);
199 list_del(&task->u.tk_wait.list);
203 * Remove request from queue.
204 * Note: must be called with spin lock held.
206 static void __rpc_remove_wait_queue(struct rpc_task *task)
208 struct rpc_wait_queue *queue;
209 queue = task->u.tk_wait.rpc_waitq;
211 if (RPC_IS_PRIORITY(queue))
212 __rpc_remove_wait_queue_priority(task);
214 list_del(&task->u.tk_wait.list);
216 dprintk("RPC: %5u removed from queue %p \"%s\"\n",
217 task->tk_pid, queue, rpc_qname(queue));
220 static inline void rpc_set_waitqueue_priority(struct rpc_wait_queue *queue, int priority)
222 queue->priority = priority;
223 queue->count = 1 << (priority * 2);
226 static inline void rpc_set_waitqueue_cookie(struct rpc_wait_queue *queue, unsigned long cookie)
228 queue->cookie = cookie;
229 queue->nr = RPC_BATCH_COUNT;
232 static inline void rpc_reset_waitqueue_priority(struct rpc_wait_queue *queue)
234 rpc_set_waitqueue_priority(queue, queue->maxpriority);
235 rpc_set_waitqueue_cookie(queue, 0);
238 static void __rpc_init_priority_wait_queue(struct rpc_wait_queue *queue, const char *qname, int maxprio)
242 spin_lock_init(&queue->lock);
243 for (i = 0; i < ARRAY_SIZE(queue->tasks); i++)
244 INIT_LIST_HEAD(&queue->tasks[i]);
245 queue->maxpriority = maxprio;
246 rpc_reset_waitqueue_priority(queue);
252 void rpc_init_priority_wait_queue(struct rpc_wait_queue *queue, const char *qname)
254 __rpc_init_priority_wait_queue(queue, qname, RPC_PRIORITY_HIGH);
257 void rpc_init_wait_queue(struct rpc_wait_queue *queue, const char *qname)
259 __rpc_init_priority_wait_queue(queue, qname, 0);
261 EXPORT_SYMBOL(rpc_init_wait_queue);
263 static int rpc_wait_bit_interruptible(void *word)
265 if (signal_pending(current))
271 static void rpc_set_active(struct rpc_task *task)
273 struct rpc_clnt *clnt;
274 if (test_and_set_bit(RPC_TASK_ACTIVE, &task->tk_runstate) != 0)
277 task->tk_magic = RPC_TASK_MAGIC_ID;
278 spin_lock(&rpc_sched_lock);
279 task->tk_pid = rpc_task_id++;
280 spin_unlock(&rpc_sched_lock);
282 /* Add to global list of all tasks */
283 clnt = task->tk_client;
285 spin_lock(&clnt->cl_lock);
286 list_add_tail(&task->tk_task, &clnt->cl_tasks);
287 spin_unlock(&clnt->cl_lock);
292 * Mark an RPC call as having completed by clearing the 'active' bit
294 static void rpc_mark_complete_task(struct rpc_task *task)
296 smp_mb__before_clear_bit();
297 clear_bit(RPC_TASK_ACTIVE, &task->tk_runstate);
298 smp_mb__after_clear_bit();
299 wake_up_bit(&task->tk_runstate, RPC_TASK_ACTIVE);
303 * Allow callers to wait for completion of an RPC call
305 int __rpc_wait_for_completion_task(struct rpc_task *task, int (*action)(void *))
308 action = rpc_wait_bit_interruptible;
309 return wait_on_bit(&task->tk_runstate, RPC_TASK_ACTIVE,
310 action, TASK_INTERRUPTIBLE);
312 EXPORT_SYMBOL(__rpc_wait_for_completion_task);
315 * Make an RPC task runnable.
317 * Note: If the task is ASYNC, this must be called with
318 * the spinlock held to protect the wait queue operation.
320 static void rpc_make_runnable(struct rpc_task *task)
322 BUG_ON(task->tk_timeout_fn);
323 rpc_clear_queued(task);
324 if (rpc_test_and_set_running(task))
326 /* We might have raced */
327 if (RPC_IS_QUEUED(task)) {
328 rpc_clear_running(task);
331 if (RPC_IS_ASYNC(task)) {
334 INIT_WORK(&task->u.tk_work, rpc_async_schedule);
335 status = queue_work(task->tk_workqueue, &task->u.tk_work);
337 printk(KERN_WARNING "RPC: failed to add task to queue: error: %d!\n", status);
338 task->tk_status = status;
342 wake_up_bit(&task->tk_runstate, RPC_TASK_QUEUED);
346 * Prepare for sleeping on a wait queue.
347 * By always appending tasks to the list we ensure FIFO behavior.
348 * NB: An RPC task will only receive interrupt-driven events as long
349 * as it's on a wait queue.
351 static void __rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
352 rpc_action action, rpc_action timer)
354 dprintk("RPC: %5u sleep_on(queue \"%s\" time %lu)\n",
355 task->tk_pid, rpc_qname(q), jiffies);
357 if (!RPC_IS_ASYNC(task) && !RPC_IS_ACTIVATED(task)) {
358 printk(KERN_ERR "RPC: Inactive synchronous task put to sleep!\n");
362 __rpc_add_wait_queue(q, task);
364 BUG_ON(task->tk_callback != NULL);
365 task->tk_callback = action;
366 __rpc_add_timer(task, timer);
369 void rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
370 rpc_action action, rpc_action timer)
372 /* Mark the task as being activated if so needed */
373 rpc_set_active(task);
376 * Protect the queue operations.
378 spin_lock_bh(&q->lock);
379 __rpc_sleep_on(q, task, action, timer);
380 spin_unlock_bh(&q->lock);
384 * __rpc_do_wake_up_task - wake up a single rpc_task
385 * @task: task to be woken up
387 * Caller must hold queue->lock, and have cleared the task queued flag.
389 static void __rpc_do_wake_up_task(struct rpc_task *task)
391 dprintk("RPC: %5u __rpc_wake_up_task (now %lu)\n",
392 task->tk_pid, jiffies);
395 BUG_ON(task->tk_magic != RPC_TASK_MAGIC_ID);
397 /* Has the task been executed yet? If not, we cannot wake it up! */
398 if (!RPC_IS_ACTIVATED(task)) {
399 printk(KERN_ERR "RPC: Inactive task (%p) being woken up!\n", task);
403 __rpc_disable_timer(task);
404 __rpc_remove_wait_queue(task);
406 rpc_make_runnable(task);
408 dprintk("RPC: __rpc_wake_up_task done\n");
412 * Wake up the specified task
414 static void __rpc_wake_up_task(struct rpc_task *task)
416 if (rpc_start_wakeup(task)) {
417 if (RPC_IS_QUEUED(task))
418 __rpc_do_wake_up_task(task);
419 rpc_finish_wakeup(task);
424 * Default timeout handler if none specified by user
427 __rpc_default_timer(struct rpc_task *task)
429 dprintk("RPC: %5u timeout (default timer)\n", task->tk_pid);
430 task->tk_status = -ETIMEDOUT;
431 rpc_wake_up_task(task);
435 * Wake up the specified task
437 void rpc_wake_up_task(struct rpc_task *task)
440 if (rpc_start_wakeup(task)) {
441 if (RPC_IS_QUEUED(task)) {
442 struct rpc_wait_queue *queue = task->u.tk_wait.rpc_waitq;
444 /* Note: we're already in a bh-safe context */
445 spin_lock(&queue->lock);
446 __rpc_do_wake_up_task(task);
447 spin_unlock(&queue->lock);
449 rpc_finish_wakeup(task);
451 rcu_read_unlock_bh();
455 * Wake up the next task on a priority queue.
457 static struct rpc_task * __rpc_wake_up_next_priority(struct rpc_wait_queue *queue)
460 struct rpc_task *task;
463 * Service a batch of tasks from a single cookie.
465 q = &queue->tasks[queue->priority];
466 if (!list_empty(q)) {
467 task = list_entry(q->next, struct rpc_task, u.tk_wait.list);
468 if (queue->cookie == task->tk_cookie) {
471 list_move_tail(&task->u.tk_wait.list, q);
474 * Check if we need to switch queues.
481 * Service the next queue.
484 if (q == &queue->tasks[0])
485 q = &queue->tasks[queue->maxpriority];
488 if (!list_empty(q)) {
489 task = list_entry(q->next, struct rpc_task, u.tk_wait.list);
492 } while (q != &queue->tasks[queue->priority]);
494 rpc_reset_waitqueue_priority(queue);
498 rpc_set_waitqueue_priority(queue, (unsigned int)(q - &queue->tasks[0]));
500 rpc_set_waitqueue_cookie(queue, task->tk_cookie);
502 __rpc_wake_up_task(task);
507 * Wake up the next task on the wait queue.
509 struct rpc_task * rpc_wake_up_next(struct rpc_wait_queue *queue)
511 struct rpc_task *task = NULL;
513 dprintk("RPC: wake_up_next(%p \"%s\")\n",
514 queue, rpc_qname(queue));
516 spin_lock(&queue->lock);
517 if (RPC_IS_PRIORITY(queue))
518 task = __rpc_wake_up_next_priority(queue);
520 task_for_first(task, &queue->tasks[0])
521 __rpc_wake_up_task(task);
523 spin_unlock(&queue->lock);
524 rcu_read_unlock_bh();
530 * rpc_wake_up - wake up all rpc_tasks
531 * @queue: rpc_wait_queue on which the tasks are sleeping
535 void rpc_wake_up(struct rpc_wait_queue *queue)
537 struct rpc_task *task, *next;
538 struct list_head *head;
541 spin_lock(&queue->lock);
542 head = &queue->tasks[queue->maxpriority];
544 list_for_each_entry_safe(task, next, head, u.tk_wait.list)
545 __rpc_wake_up_task(task);
546 if (head == &queue->tasks[0])
550 spin_unlock(&queue->lock);
551 rcu_read_unlock_bh();
555 * rpc_wake_up_status - wake up all rpc_tasks and set their status value.
556 * @queue: rpc_wait_queue on which the tasks are sleeping
557 * @status: status value to set
561 void rpc_wake_up_status(struct rpc_wait_queue *queue, int status)
563 struct rpc_task *task, *next;
564 struct list_head *head;
567 spin_lock(&queue->lock);
568 head = &queue->tasks[queue->maxpriority];
570 list_for_each_entry_safe(task, next, head, u.tk_wait.list) {
571 task->tk_status = status;
572 __rpc_wake_up_task(task);
574 if (head == &queue->tasks[0])
578 spin_unlock(&queue->lock);
579 rcu_read_unlock_bh();
582 static void __rpc_atrun(struct rpc_task *task)
584 rpc_wake_up_task(task);
588 * Run a task at a later time
590 void rpc_delay(struct rpc_task *task, unsigned long delay)
592 task->tk_timeout = delay;
593 rpc_sleep_on(&delay_queue, task, NULL, __rpc_atrun);
597 * Helper to call task->tk_ops->rpc_call_prepare
599 static void rpc_prepare_task(struct rpc_task *task)
602 task->tk_ops->rpc_call_prepare(task, task->tk_calldata);
607 * Helper that calls task->tk_ops->rpc_call_done if it exists
609 void rpc_exit_task(struct rpc_task *task)
611 task->tk_action = NULL;
612 if (task->tk_ops->rpc_call_done != NULL) {
614 task->tk_ops->rpc_call_done(task, task->tk_calldata);
616 if (task->tk_action != NULL) {
617 WARN_ON(RPC_ASSASSINATED(task));
618 /* Always release the RPC slot and buffer memory */
623 EXPORT_SYMBOL(rpc_exit_task);
625 void rpc_release_calldata(const struct rpc_call_ops *ops, void *calldata)
627 if (ops->rpc_release != NULL) {
629 ops->rpc_release(calldata);
635 * This is the RPC `scheduler' (or rather, the finite state machine).
637 static void __rpc_execute(struct rpc_task *task)
641 dprintk("RPC: %5u __rpc_execute flags=0x%x\n",
642 task->tk_pid, task->tk_flags);
644 BUG_ON(RPC_IS_QUEUED(task));
648 * Garbage collection of pending timers...
650 rpc_delete_timer(task);
653 * Execute any pending callback.
655 if (RPC_DO_CALLBACK(task)) {
656 /* Define a callback save pointer */
657 void (*save_callback)(struct rpc_task *);
660 * If a callback exists, save it, reset it,
662 * The save is needed to stop from resetting
663 * another callback set within the callback handler
666 save_callback=task->tk_callback;
667 task->tk_callback=NULL;
672 * Perform the next FSM step.
673 * tk_action may be NULL when the task has been killed
676 if (!RPC_IS_QUEUED(task)) {
677 if (task->tk_action == NULL)
679 task->tk_action(task);
683 * Lockless check for whether task is sleeping or not.
685 if (!RPC_IS_QUEUED(task))
687 rpc_clear_running(task);
688 if (RPC_IS_ASYNC(task)) {
689 /* Careful! we may have raced... */
690 if (RPC_IS_QUEUED(task))
692 if (rpc_test_and_set_running(task))
697 /* sync task: sleep here */
698 dprintk("RPC: %5u sync task going to sleep\n", task->tk_pid);
699 /* Note: Caller should be using rpc_clnt_sigmask() */
700 status = out_of_line_wait_on_bit(&task->tk_runstate,
701 RPC_TASK_QUEUED, rpc_wait_bit_interruptible,
703 if (status == -ERESTARTSYS) {
705 * When a sync task receives a signal, it exits with
706 * -ERESTARTSYS. In order to catch any callbacks that
707 * clean up after sleeping on some queue, we don't
708 * break the loop here, but go around once more.
710 dprintk("RPC: %5u got signal\n", task->tk_pid);
711 task->tk_flags |= RPC_TASK_KILLED;
712 rpc_exit(task, -ERESTARTSYS);
713 rpc_wake_up_task(task);
715 rpc_set_running(task);
716 dprintk("RPC: %5u sync task resuming\n", task->tk_pid);
719 dprintk("RPC: %5u return %d, status %d\n", task->tk_pid, status,
721 /* Release all resources associated with the task */
722 rpc_release_task(task);
726 * User-visible entry point to the scheduler.
728 * This may be called recursively if e.g. an async NFS task updates
729 * the attributes and finds that dirty pages must be flushed.
730 * NOTE: Upon exit of this function the task is guaranteed to be
731 * released. In particular note that tk_release() will have
732 * been called, so your task memory may have been freed.
734 void rpc_execute(struct rpc_task *task)
736 rpc_set_active(task);
737 rpc_set_running(task);
741 static void rpc_async_schedule(struct work_struct *work)
743 __rpc_execute(container_of(work, struct rpc_task, u.tk_work));
752 * rpc_malloc - allocate an RPC buffer
753 * @task: RPC task that will use this buffer
754 * @size: requested byte size
756 * To prevent rpciod from hanging, this allocator never sleeps,
757 * returning NULL if the request cannot be serviced immediately.
758 * The caller can arrange to sleep in a way that is safe for rpciod.
760 * Most requests are 'small' (under 2KiB) and can be serviced from a
761 * mempool, ensuring that NFS reads and writes can always proceed,
762 * and that there is good locality of reference for these buffers.
764 * In order to avoid memory starvation triggering more writebacks of
765 * NFS requests, we avoid using GFP_KERNEL.
767 void *rpc_malloc(struct rpc_task *task, size_t size)
769 struct rpc_buffer *buf;
770 gfp_t gfp = RPC_IS_SWAPPER(task) ? GFP_ATOMIC : GFP_NOWAIT;
772 size += sizeof(struct rpc_buffer);
773 if (size <= RPC_BUFFER_MAXSIZE)
774 buf = mempool_alloc(rpc_buffer_mempool, gfp);
776 buf = kmalloc(size, gfp);
782 dprintk("RPC: %5u allocated buffer of size %zu at %p\n",
783 task->tk_pid, size, buf);
788 * rpc_free - free buffer allocated via rpc_malloc
789 * @buffer: buffer to free
792 void rpc_free(void *buffer)
795 struct rpc_buffer *buf;
800 buf = container_of(buffer, struct rpc_buffer, data);
803 dprintk("RPC: freeing buffer of size %zu at %p\n",
806 if (size <= RPC_BUFFER_MAXSIZE)
807 mempool_free(buf, rpc_buffer_mempool);
813 * Creation and deletion of RPC task structures
815 void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt, int flags, const struct rpc_call_ops *tk_ops, void *calldata)
817 memset(task, 0, sizeof(*task));
818 init_timer(&task->tk_timer);
819 task->tk_timer.data = (unsigned long) task;
820 task->tk_timer.function = (void (*)(unsigned long)) rpc_run_timer;
821 atomic_set(&task->tk_count, 1);
822 task->tk_client = clnt;
823 task->tk_flags = flags;
824 task->tk_ops = tk_ops;
825 if (tk_ops->rpc_call_prepare != NULL)
826 task->tk_action = rpc_prepare_task;
827 task->tk_calldata = calldata;
828 INIT_LIST_HEAD(&task->tk_task);
830 /* Initialize retry counters */
831 task->tk_garb_retry = 2;
832 task->tk_cred_retry = 2;
834 task->tk_priority = RPC_PRIORITY_NORMAL;
835 task->tk_cookie = (unsigned long)current;
837 /* Initialize workqueue for async tasks */
838 task->tk_workqueue = rpciod_workqueue;
841 atomic_inc(&clnt->cl_users);
842 if (clnt->cl_softrtry)
843 task->tk_flags |= RPC_TASK_SOFT;
845 task->tk_flags |= RPC_TASK_NOINTR;
848 BUG_ON(task->tk_ops == NULL);
850 /* starting timestamp */
851 task->tk_start = jiffies;
853 dprintk("RPC: new task initialized, procpid %u\n",
857 static struct rpc_task *
860 return (struct rpc_task *)mempool_alloc(rpc_task_mempool, GFP_NOFS);
863 static void rpc_free_task(struct rcu_head *rcu)
865 struct rpc_task *task = container_of(rcu, struct rpc_task, u.tk_rcu);
866 dprintk("RPC: %5u freeing task\n", task->tk_pid);
867 mempool_free(task, rpc_task_mempool);
871 * Create a new task for the specified client. We have to
872 * clean up after an allocation failure, as the client may
873 * have specified "oneshot".
875 struct rpc_task *rpc_new_task(struct rpc_clnt *clnt, int flags, const struct rpc_call_ops *tk_ops, void *calldata)
877 struct rpc_task *task;
879 task = rpc_alloc_task();
883 rpc_init_task(task, clnt, flags, tk_ops, calldata);
885 dprintk("RPC: allocated task %p\n", task);
886 task->tk_flags |= RPC_TASK_DYNAMIC;
891 /* Check whether to release the client */
893 printk("rpc_new_task: failed, users=%d, oneshot=%d\n",
894 atomic_read(&clnt->cl_users), clnt->cl_oneshot);
895 atomic_inc(&clnt->cl_users); /* pretend we were used ... */
896 rpc_release_client(clnt);
902 void rpc_put_task(struct rpc_task *task)
904 const struct rpc_call_ops *tk_ops = task->tk_ops;
905 void *calldata = task->tk_calldata;
907 if (!atomic_dec_and_test(&task->tk_count))
909 /* Release resources */
912 if (task->tk_msg.rpc_cred)
913 rpcauth_unbindcred(task);
914 if (task->tk_client) {
915 rpc_release_client(task->tk_client);
916 task->tk_client = NULL;
918 if (task->tk_flags & RPC_TASK_DYNAMIC)
919 call_rcu_bh(&task->u.tk_rcu, rpc_free_task);
920 rpc_release_calldata(tk_ops, calldata);
922 EXPORT_SYMBOL(rpc_put_task);
924 static void rpc_release_task(struct rpc_task *task)
927 BUG_ON(task->tk_magic != RPC_TASK_MAGIC_ID);
929 dprintk("RPC: %5u release task\n", task->tk_pid);
931 if (!list_empty(&task->tk_task)) {
932 struct rpc_clnt *clnt = task->tk_client;
933 /* Remove from client task list */
934 spin_lock(&clnt->cl_lock);
935 list_del(&task->tk_task);
936 spin_unlock(&clnt->cl_lock);
938 BUG_ON (RPC_IS_QUEUED(task));
940 /* Synchronously delete any running timer */
941 rpc_delete_timer(task);
946 /* Wake up anyone who is waiting for task completion */
947 rpc_mark_complete_task(task);
953 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
954 * @clnt: pointer to RPC client
957 * @data: user call data
959 struct rpc_task *rpc_run_task(struct rpc_clnt *clnt, int flags,
960 const struct rpc_call_ops *ops,
963 struct rpc_task *task;
964 task = rpc_new_task(clnt, flags, ops, data);
966 rpc_release_calldata(ops, data);
967 return ERR_PTR(-ENOMEM);
969 atomic_inc(&task->tk_count);
973 EXPORT_SYMBOL(rpc_run_task);
976 * Kill all tasks for the given client.
977 * XXX: kill their descendants as well?
979 void rpc_killall_tasks(struct rpc_clnt *clnt)
981 struct rpc_task *rovr;
984 if (list_empty(&clnt->cl_tasks))
986 dprintk("RPC: killing all tasks for client %p\n", clnt);
988 * Spin lock all_tasks to prevent changes...
990 spin_lock(&clnt->cl_lock);
991 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
992 if (! RPC_IS_ACTIVATED(rovr))
994 if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
995 rovr->tk_flags |= RPC_TASK_KILLED;
996 rpc_exit(rovr, -EIO);
997 rpc_wake_up_task(rovr);
1000 spin_unlock(&clnt->cl_lock);
1003 static void rpciod_killall(void)
1005 struct rpc_clnt *clnt;
1006 unsigned long flags;
1009 clear_thread_flag(TIF_SIGPENDING);
1011 spin_lock(&rpc_sched_lock);
1012 list_for_each_entry(clnt, &all_clients, cl_clients)
1013 rpc_killall_tasks(clnt);
1014 spin_unlock(&rpc_sched_lock);
1015 flush_workqueue(rpciod_workqueue);
1016 if (!list_empty(&all_clients))
1018 dprintk("RPC: rpciod_killall: waiting for tasks "
1020 wait_event_timeout(client_kill_wait,
1021 list_empty(&all_clients), 1*HZ);
1024 spin_lock_irqsave(¤t->sighand->siglock, flags);
1025 recalc_sigpending();
1026 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
1029 void rpc_register_client(struct rpc_clnt *clnt)
1031 spin_lock(&rpc_sched_lock);
1032 list_add(&clnt->cl_clients, &all_clients);
1033 spin_unlock(&rpc_sched_lock);
1036 void rpc_unregister_client(struct rpc_clnt *clnt)
1038 spin_lock(&rpc_sched_lock);
1039 list_del(&clnt->cl_clients);
1040 if (list_empty(&all_clients))
1041 wake_up(&client_kill_wait);
1042 spin_unlock(&rpc_sched_lock);
1046 * Start up the rpciod process if it's not already running.
1051 struct workqueue_struct *wq;
1054 mutex_lock(&rpciod_mutex);
1055 dprintk("RPC: rpciod_up: users %u\n", rpciod_users);
1057 if (rpciod_workqueue)
1060 * If there's no pid, we should be the first user.
1062 if (rpciod_users > 1)
1063 printk(KERN_WARNING "rpciod_up: no workqueue, %u users??\n", rpciod_users);
1065 * Create the rpciod thread and wait for it to start.
1068 wq = create_workqueue("rpciod");
1070 printk(KERN_WARNING "rpciod_up: create workqueue failed, error=%d\n", error);
1074 rpciod_workqueue = wq;
1077 mutex_unlock(&rpciod_mutex);
1084 mutex_lock(&rpciod_mutex);
1085 dprintk("RPC: rpciod_down sema %u\n", rpciod_users);
1090 printk(KERN_WARNING "rpciod_down: no users??\n");
1092 if (!rpciod_workqueue) {
1093 dprintk("RPC: rpciod_down: Nothing to do!\n");
1098 destroy_workqueue(rpciod_workqueue);
1099 rpciod_workqueue = NULL;
1101 mutex_unlock(&rpciod_mutex);
1105 void rpc_show_tasks(void)
1107 struct rpc_clnt *clnt;
1110 spin_lock(&rpc_sched_lock);
1111 if (list_empty(&all_clients))
1113 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
1114 "-rpcwait -action- ---ops--\n");
1115 list_for_each_entry(clnt, &all_clients, cl_clients) {
1116 if (list_empty(&clnt->cl_tasks))
1118 spin_lock(&clnt->cl_lock);
1119 list_for_each_entry(t, &clnt->cl_tasks, tk_task) {
1120 const char *rpc_waitq = "none";
1122 if (RPC_IS_QUEUED(t))
1123 rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
1125 printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n",
1127 (t->tk_msg.rpc_proc ? t->tk_msg.rpc_proc->p_proc : -1),
1128 t->tk_flags, t->tk_status,
1130 (t->tk_client ? t->tk_client->cl_prog : 0),
1131 t->tk_rqstp, t->tk_timeout,
1133 t->tk_action, t->tk_ops);
1135 spin_unlock(&clnt->cl_lock);
1138 spin_unlock(&rpc_sched_lock);
1143 rpc_destroy_mempool(void)
1145 if (rpc_buffer_mempool)
1146 mempool_destroy(rpc_buffer_mempool);
1147 if (rpc_task_mempool)
1148 mempool_destroy(rpc_task_mempool);
1150 kmem_cache_destroy(rpc_task_slabp);
1151 if (rpc_buffer_slabp)
1152 kmem_cache_destroy(rpc_buffer_slabp);
1156 rpc_init_mempool(void)
1158 rpc_task_slabp = kmem_cache_create("rpc_tasks",
1159 sizeof(struct rpc_task),
1160 0, SLAB_HWCACHE_ALIGN,
1162 if (!rpc_task_slabp)
1164 rpc_buffer_slabp = kmem_cache_create("rpc_buffers",
1166 0, SLAB_HWCACHE_ALIGN,
1168 if (!rpc_buffer_slabp)
1170 rpc_task_mempool = mempool_create_slab_pool(RPC_TASK_POOLSIZE,
1172 if (!rpc_task_mempool)
1174 rpc_buffer_mempool = mempool_create_slab_pool(RPC_BUFFER_POOLSIZE,
1176 if (!rpc_buffer_mempool)
1180 rpc_destroy_mempool();