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>
22 #include <linux/sunrpc/clnt.h>
23 #include <linux/sunrpc/xprt.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 kmem_cache_t *rpc_task_slabp __read_mostly;
38 static kmem_cache_t *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_free(struct rpc_task *task);
46 static void rpc_async_schedule(void *);
49 * RPC tasks that create another task (e.g. for contacting the portmapper)
50 * will wait on this queue for their child's completion
52 static RPC_WAITQ(childq, "childq");
55 * RPC tasks sit here while waiting for conditions to improve.
57 static RPC_WAITQ(delay_queue, "delayq");
60 * All RPC tasks are linked into this list
62 static LIST_HEAD(all_tasks);
65 * rpciod-related stuff
67 static DECLARE_MUTEX(rpciod_sema);
68 static unsigned int rpciod_users;
69 static struct workqueue_struct *rpciod_workqueue;
72 * Spinlock for other critical sections of code.
74 static DEFINE_SPINLOCK(rpc_sched_lock);
77 * Disable the timer for a given RPC task. Should be called with
78 * queue->lock and bh_disabled in order to avoid races within
82 __rpc_disable_timer(struct rpc_task *task)
84 dprintk("RPC: %4d disabling timer\n", task->tk_pid);
85 task->tk_timeout_fn = NULL;
90 * Run a timeout function.
91 * We use the callback in order to allow __rpc_wake_up_task()
92 * and friends to disable the timer synchronously on SMP systems
93 * without calling del_timer_sync(). The latter could cause a
94 * deadlock if called while we're holding spinlocks...
96 static void rpc_run_timer(struct rpc_task *task)
98 void (*callback)(struct rpc_task *);
100 callback = task->tk_timeout_fn;
101 task->tk_timeout_fn = NULL;
102 if (callback && RPC_IS_QUEUED(task)) {
103 dprintk("RPC: %4d running timer\n", task->tk_pid);
106 smp_mb__before_clear_bit();
107 clear_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate);
108 smp_mb__after_clear_bit();
112 * Set up a timer for the current task.
115 __rpc_add_timer(struct rpc_task *task, rpc_action timer)
117 if (!task->tk_timeout)
120 dprintk("RPC: %4d setting alarm for %lu ms\n",
121 task->tk_pid, task->tk_timeout * 1000 / HZ);
124 task->tk_timeout_fn = timer;
126 task->tk_timeout_fn = __rpc_default_timer;
127 set_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate);
128 mod_timer(&task->tk_timer, jiffies + task->tk_timeout);
132 * Delete any timer for the current task. Because we use del_timer_sync(),
133 * this function should never be called while holding queue->lock.
136 rpc_delete_timer(struct rpc_task *task)
138 if (RPC_IS_QUEUED(task))
140 if (test_and_clear_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate)) {
141 del_singleshot_timer_sync(&task->tk_timer);
142 dprintk("RPC: %4d deleting timer\n", task->tk_pid);
147 * Add new request to a priority queue.
149 static void __rpc_add_wait_queue_priority(struct rpc_wait_queue *queue, struct rpc_task *task)
154 INIT_LIST_HEAD(&task->u.tk_wait.links);
155 q = &queue->tasks[task->tk_priority];
156 if (unlikely(task->tk_priority > queue->maxpriority))
157 q = &queue->tasks[queue->maxpriority];
158 list_for_each_entry(t, q, u.tk_wait.list) {
159 if (t->tk_cookie == task->tk_cookie) {
160 list_add_tail(&task->u.tk_wait.list, &t->u.tk_wait.links);
164 list_add_tail(&task->u.tk_wait.list, q);
168 * Add new request to wait queue.
170 * Swapper tasks always get inserted at the head of the queue.
171 * This should avoid many nasty memory deadlocks and hopefully
172 * improve overall performance.
173 * Everyone else gets appended to the queue to ensure proper FIFO behavior.
175 static void __rpc_add_wait_queue(struct rpc_wait_queue *queue, struct rpc_task *task)
177 BUG_ON (RPC_IS_QUEUED(task));
179 if (RPC_IS_PRIORITY(queue))
180 __rpc_add_wait_queue_priority(queue, task);
181 else if (RPC_IS_SWAPPER(task))
182 list_add(&task->u.tk_wait.list, &queue->tasks[0]);
184 list_add_tail(&task->u.tk_wait.list, &queue->tasks[0]);
185 task->u.tk_wait.rpc_waitq = queue;
186 rpc_set_queued(task);
188 dprintk("RPC: %4d added to queue %p \"%s\"\n",
189 task->tk_pid, queue, rpc_qname(queue));
193 * Remove request from a priority queue.
195 static void __rpc_remove_wait_queue_priority(struct rpc_task *task)
199 if (!list_empty(&task->u.tk_wait.links)) {
200 t = list_entry(task->u.tk_wait.links.next, struct rpc_task, u.tk_wait.list);
201 list_move(&t->u.tk_wait.list, &task->u.tk_wait.list);
202 list_splice_init(&task->u.tk_wait.links, &t->u.tk_wait.links);
204 list_del(&task->u.tk_wait.list);
208 * Remove request from queue.
209 * Note: must be called with spin lock held.
211 static void __rpc_remove_wait_queue(struct rpc_task *task)
213 struct rpc_wait_queue *queue;
214 queue = task->u.tk_wait.rpc_waitq;
216 if (RPC_IS_PRIORITY(queue))
217 __rpc_remove_wait_queue_priority(task);
219 list_del(&task->u.tk_wait.list);
220 dprintk("RPC: %4d removed from queue %p \"%s\"\n",
221 task->tk_pid, queue, rpc_qname(queue));
224 static inline void rpc_set_waitqueue_priority(struct rpc_wait_queue *queue, int priority)
226 queue->priority = priority;
227 queue->count = 1 << (priority * 2);
230 static inline void rpc_set_waitqueue_cookie(struct rpc_wait_queue *queue, unsigned long cookie)
232 queue->cookie = cookie;
233 queue->nr = RPC_BATCH_COUNT;
236 static inline void rpc_reset_waitqueue_priority(struct rpc_wait_queue *queue)
238 rpc_set_waitqueue_priority(queue, queue->maxpriority);
239 rpc_set_waitqueue_cookie(queue, 0);
242 static void __rpc_init_priority_wait_queue(struct rpc_wait_queue *queue, const char *qname, int maxprio)
246 spin_lock_init(&queue->lock);
247 for (i = 0; i < ARRAY_SIZE(queue->tasks); i++)
248 INIT_LIST_HEAD(&queue->tasks[i]);
249 queue->maxpriority = maxprio;
250 rpc_reset_waitqueue_priority(queue);
256 void rpc_init_priority_wait_queue(struct rpc_wait_queue *queue, const char *qname)
258 __rpc_init_priority_wait_queue(queue, qname, RPC_PRIORITY_HIGH);
261 void rpc_init_wait_queue(struct rpc_wait_queue *queue, const char *qname)
263 __rpc_init_priority_wait_queue(queue, qname, 0);
265 EXPORT_SYMBOL(rpc_init_wait_queue);
268 * Make an RPC task runnable.
270 * Note: If the task is ASYNC, this must be called with
271 * the spinlock held to protect the wait queue operation.
273 static void rpc_make_runnable(struct rpc_task *task)
277 BUG_ON(task->tk_timeout_fn);
278 do_ret = rpc_test_and_set_running(task);
279 rpc_clear_queued(task);
282 if (RPC_IS_ASYNC(task)) {
285 INIT_WORK(&task->u.tk_work, rpc_async_schedule, (void *)task);
286 status = queue_work(task->tk_workqueue, &task->u.tk_work);
288 printk(KERN_WARNING "RPC: failed to add task to queue: error: %d!\n", status);
289 task->tk_status = status;
293 wake_up_bit(&task->tk_runstate, RPC_TASK_QUEUED);
297 * Place a newly initialized task on the workqueue.
300 rpc_schedule_run(struct rpc_task *task)
302 /* Don't run a child twice! */
303 if (RPC_IS_ACTIVATED(task))
306 rpc_make_runnable(task);
310 * Prepare for sleeping on a wait queue.
311 * By always appending tasks to the list we ensure FIFO behavior.
312 * NB: An RPC task will only receive interrupt-driven events as long
313 * as it's on a wait queue.
315 static void __rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
316 rpc_action action, rpc_action timer)
318 dprintk("RPC: %4d sleep_on(queue \"%s\" time %ld)\n", task->tk_pid,
319 rpc_qname(q), jiffies);
321 if (!RPC_IS_ASYNC(task) && !RPC_IS_ACTIVATED(task)) {
322 printk(KERN_ERR "RPC: Inactive synchronous task put to sleep!\n");
326 /* Mark the task as being activated if so needed */
327 if (!RPC_IS_ACTIVATED(task))
330 __rpc_add_wait_queue(q, task);
332 BUG_ON(task->tk_callback != NULL);
333 task->tk_callback = action;
334 __rpc_add_timer(task, timer);
337 void rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
338 rpc_action action, rpc_action timer)
341 * Protect the queue operations.
343 spin_lock_bh(&q->lock);
344 __rpc_sleep_on(q, task, action, timer);
345 spin_unlock_bh(&q->lock);
349 * __rpc_do_wake_up_task - wake up a single rpc_task
350 * @task: task to be woken up
352 * Caller must hold queue->lock, and have cleared the task queued flag.
354 static void __rpc_do_wake_up_task(struct rpc_task *task)
356 dprintk("RPC: %4d __rpc_wake_up_task (now %ld)\n", task->tk_pid, jiffies);
359 BUG_ON(task->tk_magic != RPC_TASK_MAGIC_ID);
361 /* Has the task been executed yet? If not, we cannot wake it up! */
362 if (!RPC_IS_ACTIVATED(task)) {
363 printk(KERN_ERR "RPC: Inactive task (%p) being woken up!\n", task);
367 __rpc_disable_timer(task);
368 __rpc_remove_wait_queue(task);
370 rpc_make_runnable(task);
372 dprintk("RPC: __rpc_wake_up_task done\n");
376 * Wake up the specified task
378 static void __rpc_wake_up_task(struct rpc_task *task)
380 if (rpc_start_wakeup(task)) {
381 if (RPC_IS_QUEUED(task))
382 __rpc_do_wake_up_task(task);
383 rpc_finish_wakeup(task);
388 * Default timeout handler if none specified by user
391 __rpc_default_timer(struct rpc_task *task)
393 dprintk("RPC: %d timeout (default timer)\n", task->tk_pid);
394 task->tk_status = -ETIMEDOUT;
395 rpc_wake_up_task(task);
399 * Wake up the specified task
401 void rpc_wake_up_task(struct rpc_task *task)
403 if (rpc_start_wakeup(task)) {
404 if (RPC_IS_QUEUED(task)) {
405 struct rpc_wait_queue *queue = task->u.tk_wait.rpc_waitq;
407 spin_lock_bh(&queue->lock);
408 __rpc_do_wake_up_task(task);
409 spin_unlock_bh(&queue->lock);
411 rpc_finish_wakeup(task);
416 * Wake up the next task on a priority queue.
418 static struct rpc_task * __rpc_wake_up_next_priority(struct rpc_wait_queue *queue)
421 struct rpc_task *task;
424 * Service a batch of tasks from a single cookie.
426 q = &queue->tasks[queue->priority];
427 if (!list_empty(q)) {
428 task = list_entry(q->next, struct rpc_task, u.tk_wait.list);
429 if (queue->cookie == task->tk_cookie) {
432 list_move_tail(&task->u.tk_wait.list, q);
435 * Check if we need to switch queues.
442 * Service the next queue.
445 if (q == &queue->tasks[0])
446 q = &queue->tasks[queue->maxpriority];
449 if (!list_empty(q)) {
450 task = list_entry(q->next, struct rpc_task, u.tk_wait.list);
453 } while (q != &queue->tasks[queue->priority]);
455 rpc_reset_waitqueue_priority(queue);
459 rpc_set_waitqueue_priority(queue, (unsigned int)(q - &queue->tasks[0]));
461 rpc_set_waitqueue_cookie(queue, task->tk_cookie);
463 __rpc_wake_up_task(task);
468 * Wake up the next task on the wait queue.
470 struct rpc_task * rpc_wake_up_next(struct rpc_wait_queue *queue)
472 struct rpc_task *task = NULL;
474 dprintk("RPC: wake_up_next(%p \"%s\")\n", queue, rpc_qname(queue));
475 spin_lock_bh(&queue->lock);
476 if (RPC_IS_PRIORITY(queue))
477 task = __rpc_wake_up_next_priority(queue);
479 task_for_first(task, &queue->tasks[0])
480 __rpc_wake_up_task(task);
482 spin_unlock_bh(&queue->lock);
488 * rpc_wake_up - wake up all rpc_tasks
489 * @queue: rpc_wait_queue on which the tasks are sleeping
493 void rpc_wake_up(struct rpc_wait_queue *queue)
495 struct rpc_task *task;
497 struct list_head *head;
498 spin_lock_bh(&queue->lock);
499 head = &queue->tasks[queue->maxpriority];
501 while (!list_empty(head)) {
502 task = list_entry(head->next, struct rpc_task, u.tk_wait.list);
503 __rpc_wake_up_task(task);
505 if (head == &queue->tasks[0])
509 spin_unlock_bh(&queue->lock);
513 * rpc_wake_up_status - wake up all rpc_tasks and set their status value.
514 * @queue: rpc_wait_queue on which the tasks are sleeping
515 * @status: status value to set
519 void rpc_wake_up_status(struct rpc_wait_queue *queue, int status)
521 struct list_head *head;
522 struct rpc_task *task;
524 spin_lock_bh(&queue->lock);
525 head = &queue->tasks[queue->maxpriority];
527 while (!list_empty(head)) {
528 task = list_entry(head->next, struct rpc_task, u.tk_wait.list);
529 task->tk_status = status;
530 __rpc_wake_up_task(task);
532 if (head == &queue->tasks[0])
536 spin_unlock_bh(&queue->lock);
540 * Run a task at a later time
542 static void __rpc_atrun(struct rpc_task *);
544 rpc_delay(struct rpc_task *task, unsigned long delay)
546 task->tk_timeout = delay;
547 rpc_sleep_on(&delay_queue, task, NULL, __rpc_atrun);
551 __rpc_atrun(struct rpc_task *task)
554 rpc_wake_up_task(task);
558 * Helper that calls task->tk_ops->rpc_call_done if it exists
560 void rpc_exit_task(struct rpc_task *task)
562 task->tk_action = NULL;
563 if (task->tk_ops->rpc_call_done != NULL) {
564 task->tk_ops->rpc_call_done(task, task->tk_calldata);
565 if (task->tk_action != NULL) {
566 WARN_ON(RPC_ASSASSINATED(task));
567 /* Always release the RPC slot and buffer memory */
573 EXPORT_SYMBOL(rpc_exit_task);
575 static int rpc_wait_bit_interruptible(void *word)
577 if (signal_pending(current))
584 * This is the RPC `scheduler' (or rather, the finite state machine).
586 static int __rpc_execute(struct rpc_task *task)
590 dprintk("RPC: %4d rpc_execute flgs %x\n",
591 task->tk_pid, task->tk_flags);
593 BUG_ON(RPC_IS_QUEUED(task));
597 * Garbage collection of pending timers...
599 rpc_delete_timer(task);
602 * Execute any pending callback.
604 if (RPC_DO_CALLBACK(task)) {
605 /* Define a callback save pointer */
606 void (*save_callback)(struct rpc_task *);
609 * If a callback exists, save it, reset it,
611 * The save is needed to stop from resetting
612 * another callback set within the callback handler
615 save_callback=task->tk_callback;
616 task->tk_callback=NULL;
623 * Perform the next FSM step.
624 * tk_action may be NULL when the task has been killed
627 if (!RPC_IS_QUEUED(task)) {
628 if (task->tk_action == NULL)
631 task->tk_action(task);
636 * Lockless check for whether task is sleeping or not.
638 if (!RPC_IS_QUEUED(task))
640 rpc_clear_running(task);
641 if (RPC_IS_ASYNC(task)) {
642 /* Careful! we may have raced... */
643 if (RPC_IS_QUEUED(task))
645 if (rpc_test_and_set_running(task))
650 /* sync task: sleep here */
651 dprintk("RPC: %4d sync task going to sleep\n", task->tk_pid);
652 /* Note: Caller should be using rpc_clnt_sigmask() */
653 status = out_of_line_wait_on_bit(&task->tk_runstate,
654 RPC_TASK_QUEUED, rpc_wait_bit_interruptible,
656 if (status == -ERESTARTSYS) {
658 * When a sync task receives a signal, it exits with
659 * -ERESTARTSYS. In order to catch any callbacks that
660 * clean up after sleeping on some queue, we don't
661 * break the loop here, but go around once more.
663 dprintk("RPC: %4d got signal\n", task->tk_pid);
664 task->tk_flags |= RPC_TASK_KILLED;
665 rpc_exit(task, -ERESTARTSYS);
666 rpc_wake_up_task(task);
668 rpc_set_running(task);
669 dprintk("RPC: %4d sync task resuming\n", task->tk_pid);
672 dprintk("RPC: %4d exit() = %d\n", task->tk_pid, task->tk_status);
673 status = task->tk_status;
675 /* Release all resources associated with the task */
676 rpc_release_task(task);
681 * User-visible entry point to the scheduler.
683 * This may be called recursively if e.g. an async NFS task updates
684 * the attributes and finds that dirty pages must be flushed.
685 * NOTE: Upon exit of this function the task is guaranteed to be
686 * released. In particular note that tk_release() will have
687 * been called, so your task memory may have been freed.
690 rpc_execute(struct rpc_task *task)
692 BUG_ON(task->tk_active);
695 rpc_set_running(task);
696 return __rpc_execute(task);
699 static void rpc_async_schedule(void *arg)
701 __rpc_execute((struct rpc_task *)arg);
705 * Allocate memory for RPC purposes.
707 * We try to ensure that some NFS reads and writes can always proceed
708 * by using a mempool when allocating 'small' buffers.
709 * In order to avoid memory starvation triggering more writebacks of
710 * NFS requests, we use GFP_NOFS rather than GFP_KERNEL.
713 rpc_malloc(struct rpc_task *task, size_t size)
717 if (task->tk_flags & RPC_TASK_SWAPPER)
722 if (size > RPC_BUFFER_MAXSIZE) {
723 task->tk_buffer = kmalloc(size, gfp);
725 task->tk_bufsize = size;
727 task->tk_buffer = mempool_alloc(rpc_buffer_mempool, gfp);
729 task->tk_bufsize = RPC_BUFFER_MAXSIZE;
731 return task->tk_buffer;
735 rpc_free(struct rpc_task *task)
737 if (task->tk_buffer) {
738 if (task->tk_bufsize == RPC_BUFFER_MAXSIZE)
739 mempool_free(task->tk_buffer, rpc_buffer_mempool);
741 kfree(task->tk_buffer);
742 task->tk_buffer = NULL;
743 task->tk_bufsize = 0;
748 * Creation and deletion of RPC task structures
750 void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt, int flags, const struct rpc_call_ops *tk_ops, void *calldata)
752 memset(task, 0, sizeof(*task));
753 init_timer(&task->tk_timer);
754 task->tk_timer.data = (unsigned long) task;
755 task->tk_timer.function = (void (*)(unsigned long)) rpc_run_timer;
756 task->tk_client = clnt;
757 task->tk_flags = flags;
758 task->tk_ops = tk_ops;
759 task->tk_calldata = calldata;
761 /* Initialize retry counters */
762 task->tk_garb_retry = 2;
763 task->tk_cred_retry = 2;
765 task->tk_priority = RPC_PRIORITY_NORMAL;
766 task->tk_cookie = (unsigned long)current;
768 /* Initialize workqueue for async tasks */
769 task->tk_workqueue = rpciod_workqueue;
772 atomic_inc(&clnt->cl_users);
773 if (clnt->cl_softrtry)
774 task->tk_flags |= RPC_TASK_SOFT;
776 task->tk_flags |= RPC_TASK_NOINTR;
780 task->tk_magic = RPC_TASK_MAGIC_ID;
781 task->tk_pid = rpc_task_id++;
783 /* Add to global list of all tasks */
784 spin_lock(&rpc_sched_lock);
785 list_add_tail(&task->tk_task, &all_tasks);
786 spin_unlock(&rpc_sched_lock);
788 BUG_ON(task->tk_ops == NULL);
790 dprintk("RPC: %4d new task procpid %d\n", task->tk_pid,
794 static struct rpc_task *
797 return (struct rpc_task *)mempool_alloc(rpc_task_mempool, GFP_NOFS);
800 static void rpc_free_task(struct rpc_task *task)
802 dprintk("RPC: %4d freeing task\n", task->tk_pid);
803 mempool_free(task, rpc_task_mempool);
807 * Create a new task for the specified client. We have to
808 * clean up after an allocation failure, as the client may
809 * have specified "oneshot".
811 struct rpc_task *rpc_new_task(struct rpc_clnt *clnt, int flags, const struct rpc_call_ops *tk_ops, void *calldata)
813 struct rpc_task *task;
815 task = rpc_alloc_task();
819 rpc_init_task(task, clnt, flags, tk_ops, calldata);
821 dprintk("RPC: %4d allocated task\n", task->tk_pid);
822 task->tk_flags |= RPC_TASK_DYNAMIC;
827 /* Check whether to release the client */
829 printk("rpc_new_task: failed, users=%d, oneshot=%d\n",
830 atomic_read(&clnt->cl_users), clnt->cl_oneshot);
831 atomic_inc(&clnt->cl_users); /* pretend we were used ... */
832 rpc_release_client(clnt);
837 void rpc_release_task(struct rpc_task *task)
839 const struct rpc_call_ops *tk_ops = task->tk_ops;
840 void *calldata = task->tk_calldata;
841 dprintk("RPC: %4d release task\n", task->tk_pid);
844 BUG_ON(task->tk_magic != RPC_TASK_MAGIC_ID);
847 /* Remove from global task list */
848 spin_lock(&rpc_sched_lock);
849 list_del(&task->tk_task);
850 spin_unlock(&rpc_sched_lock);
852 BUG_ON (RPC_IS_QUEUED(task));
855 /* Synchronously delete any running timer */
856 rpc_delete_timer(task);
858 /* Release resources */
861 if (task->tk_msg.rpc_cred)
862 rpcauth_unbindcred(task);
864 if (task->tk_client) {
865 rpc_release_client(task->tk_client);
866 task->tk_client = NULL;
872 if (task->tk_flags & RPC_TASK_DYNAMIC)
874 if (tk_ops->rpc_release)
875 tk_ops->rpc_release(calldata);
879 * rpc_find_parent - find the parent of a child task.
882 * Checks that the parent task is still sleeping on the
883 * queue 'childq'. If so returns a pointer to the parent.
884 * Upon failure returns NULL.
886 * Caller must hold childq.lock
888 static inline struct rpc_task *rpc_find_parent(struct rpc_task *child, struct rpc_task *parent)
890 struct rpc_task *task;
891 struct list_head *le;
893 task_for_each(task, le, &childq.tasks[0])
900 static void rpc_child_exit(struct rpc_task *child, void *calldata)
902 struct rpc_task *parent;
904 spin_lock_bh(&childq.lock);
905 if ((parent = rpc_find_parent(child, calldata)) != NULL) {
906 parent->tk_status = child->tk_status;
907 __rpc_wake_up_task(parent);
909 spin_unlock_bh(&childq.lock);
912 static const struct rpc_call_ops rpc_child_ops = {
913 .rpc_call_done = rpc_child_exit,
917 * Note: rpc_new_task releases the client after a failure.
920 rpc_new_child(struct rpc_clnt *clnt, struct rpc_task *parent)
922 struct rpc_task *task;
924 task = rpc_new_task(clnt, RPC_TASK_ASYNC | RPC_TASK_CHILD, &rpc_child_ops, parent);
930 parent->tk_status = -ENOMEM;
934 void rpc_run_child(struct rpc_task *task, struct rpc_task *child, rpc_action func)
936 spin_lock_bh(&childq.lock);
937 /* N.B. Is it possible for the child to have already finished? */
938 __rpc_sleep_on(&childq, task, func, NULL);
939 rpc_schedule_run(child);
940 spin_unlock_bh(&childq.lock);
944 * Kill all tasks for the given client.
945 * XXX: kill their descendants as well?
947 void rpc_killall_tasks(struct rpc_clnt *clnt)
949 struct rpc_task *rovr;
950 struct list_head *le;
952 dprintk("RPC: killing all tasks for client %p\n", clnt);
955 * Spin lock all_tasks to prevent changes...
957 spin_lock(&rpc_sched_lock);
958 alltask_for_each(rovr, le, &all_tasks) {
959 if (! RPC_IS_ACTIVATED(rovr))
961 if (!clnt || rovr->tk_client == clnt) {
962 rovr->tk_flags |= RPC_TASK_KILLED;
963 rpc_exit(rovr, -EIO);
964 rpc_wake_up_task(rovr);
967 spin_unlock(&rpc_sched_lock);
970 static DECLARE_MUTEX_LOCKED(rpciod_running);
972 static void rpciod_killall(void)
976 while (!list_empty(&all_tasks)) {
977 clear_thread_flag(TIF_SIGPENDING);
978 rpc_killall_tasks(NULL);
979 flush_workqueue(rpciod_workqueue);
980 if (!list_empty(&all_tasks)) {
981 dprintk("rpciod_killall: waiting for tasks to exit\n");
986 spin_lock_irqsave(¤t->sighand->siglock, flags);
988 spin_unlock_irqrestore(¤t->sighand->siglock, flags);
992 * Start up the rpciod process if it's not already running.
997 struct workqueue_struct *wq;
1001 dprintk("rpciod_up: users %d\n", rpciod_users);
1003 if (rpciod_workqueue)
1006 * If there's no pid, we should be the first user.
1008 if (rpciod_users > 1)
1009 printk(KERN_WARNING "rpciod_up: no workqueue, %d users??\n", rpciod_users);
1011 * Create the rpciod thread and wait for it to start.
1014 wq = create_workqueue("rpciod");
1016 printk(KERN_WARNING "rpciod_up: create workqueue failed, error=%d\n", error);
1020 rpciod_workqueue = wq;
1031 dprintk("rpciod_down sema %d\n", rpciod_users);
1036 printk(KERN_WARNING "rpciod_down: no users??\n");
1038 if (!rpciod_workqueue) {
1039 dprintk("rpciod_down: Nothing to do!\n");
1044 destroy_workqueue(rpciod_workqueue);
1045 rpciod_workqueue = NULL;
1051 void rpc_show_tasks(void)
1053 struct list_head *le;
1056 spin_lock(&rpc_sched_lock);
1057 if (list_empty(&all_tasks)) {
1058 spin_unlock(&rpc_sched_lock);
1061 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
1062 "-rpcwait -action- ---ops--\n");
1063 alltask_for_each(t, le, &all_tasks) {
1064 const char *rpc_waitq = "none";
1066 if (RPC_IS_QUEUED(t))
1067 rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
1069 printk("%05d %04d %04x %06d %8p %6d %8p %08ld %8s %8p %8p\n",
1071 (t->tk_msg.rpc_proc ? t->tk_msg.rpc_proc->p_proc : -1),
1072 t->tk_flags, t->tk_status,
1074 (t->tk_client ? t->tk_client->cl_prog : 0),
1075 t->tk_rqstp, t->tk_timeout,
1077 t->tk_action, t->tk_ops);
1079 spin_unlock(&rpc_sched_lock);
1084 rpc_destroy_mempool(void)
1086 if (rpc_buffer_mempool)
1087 mempool_destroy(rpc_buffer_mempool);
1088 if (rpc_task_mempool)
1089 mempool_destroy(rpc_task_mempool);
1090 if (rpc_task_slabp && kmem_cache_destroy(rpc_task_slabp))
1091 printk(KERN_INFO "rpc_task: not all structures were freed\n");
1092 if (rpc_buffer_slabp && kmem_cache_destroy(rpc_buffer_slabp))
1093 printk(KERN_INFO "rpc_buffers: not all structures were freed\n");
1097 rpc_init_mempool(void)
1099 rpc_task_slabp = kmem_cache_create("rpc_tasks",
1100 sizeof(struct rpc_task),
1101 0, SLAB_HWCACHE_ALIGN,
1103 if (!rpc_task_slabp)
1105 rpc_buffer_slabp = kmem_cache_create("rpc_buffers",
1107 0, SLAB_HWCACHE_ALIGN,
1109 if (!rpc_buffer_slabp)
1111 rpc_task_mempool = mempool_create(RPC_TASK_POOLSIZE,
1115 if (!rpc_task_mempool)
1117 rpc_buffer_mempool = mempool_create(RPC_BUFFER_POOLSIZE,
1121 if (!rpc_buffer_mempool)
1125 rpc_destroy_mempool();