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_default_timer(struct rpc_task
*task
);
42 static void rpc_async_schedule(struct work_struct
*);
43 static void rpc_release_task(struct rpc_task
*task
);
46 * RPC tasks sit here while waiting for conditions to improve.
48 static RPC_WAITQ(delay_queue
, "delayq");
51 * rpciod-related stuff
53 struct workqueue_struct
*rpciod_workqueue
;
56 * Disable the timer for a given RPC task. Should be called with
57 * queue->lock and bh_disabled in order to avoid races within
61 __rpc_disable_timer(struct rpc_task
*task
)
63 dprintk("RPC: %5u disabling timer\n", task
->tk_pid
);
64 task
->tk_timeout_fn
= NULL
;
69 * Run a timeout function.
70 * We use the callback in order to allow __rpc_wake_up_task()
71 * and friends to disable the timer synchronously on SMP systems
72 * without calling del_timer_sync(). The latter could cause a
73 * deadlock if called while we're holding spinlocks...
75 static void rpc_run_timer(struct rpc_task
*task
)
77 void (*callback
)(struct rpc_task
*);
79 callback
= task
->tk_timeout_fn
;
80 task
->tk_timeout_fn
= NULL
;
81 if (callback
&& RPC_IS_QUEUED(task
)) {
82 dprintk("RPC: %5u running timer\n", task
->tk_pid
);
85 smp_mb__before_clear_bit();
86 clear_bit(RPC_TASK_HAS_TIMER
, &task
->tk_runstate
);
87 smp_mb__after_clear_bit();
91 * Set up a timer for the current task.
94 __rpc_add_timer(struct rpc_task
*task
, rpc_action timer
)
96 if (!task
->tk_timeout
)
99 dprintk("RPC: %5u setting alarm for %lu ms\n",
100 task
->tk_pid
, task
->tk_timeout
* 1000 / HZ
);
103 task
->tk_timeout_fn
= timer
;
105 task
->tk_timeout_fn
= __rpc_default_timer
;
106 set_bit(RPC_TASK_HAS_TIMER
, &task
->tk_runstate
);
107 mod_timer(&task
->tk_timer
, jiffies
+ task
->tk_timeout
);
111 * Delete any timer for the current task. Because we use del_timer_sync(),
112 * this function should never be called while holding queue->lock.
115 rpc_delete_timer(struct rpc_task
*task
)
117 if (RPC_IS_QUEUED(task
))
119 if (test_and_clear_bit(RPC_TASK_HAS_TIMER
, &task
->tk_runstate
)) {
120 del_singleshot_timer_sync(&task
->tk_timer
);
121 dprintk("RPC: %5u deleting timer\n", task
->tk_pid
);
126 * Add new request to a priority queue.
128 static void __rpc_add_wait_queue_priority(struct rpc_wait_queue
*queue
, struct rpc_task
*task
)
133 INIT_LIST_HEAD(&task
->u
.tk_wait
.links
);
134 q
= &queue
->tasks
[task
->tk_priority
];
135 if (unlikely(task
->tk_priority
> queue
->maxpriority
))
136 q
= &queue
->tasks
[queue
->maxpriority
];
137 list_for_each_entry(t
, q
, u
.tk_wait
.list
) {
138 if (t
->tk_cookie
== task
->tk_cookie
) {
139 list_add_tail(&task
->u
.tk_wait
.list
, &t
->u
.tk_wait
.links
);
143 list_add_tail(&task
->u
.tk_wait
.list
, q
);
147 * Add new request to wait queue.
149 * Swapper tasks always get inserted at the head of the queue.
150 * This should avoid many nasty memory deadlocks and hopefully
151 * improve overall performance.
152 * Everyone else gets appended to the queue to ensure proper FIFO behavior.
154 static void __rpc_add_wait_queue(struct rpc_wait_queue
*queue
, struct rpc_task
*task
)
156 BUG_ON (RPC_IS_QUEUED(task
));
158 if (RPC_IS_PRIORITY(queue
))
159 __rpc_add_wait_queue_priority(queue
, task
);
160 else if (RPC_IS_SWAPPER(task
))
161 list_add(&task
->u
.tk_wait
.list
, &queue
->tasks
[0]);
163 list_add_tail(&task
->u
.tk_wait
.list
, &queue
->tasks
[0]);
164 task
->u
.tk_wait
.rpc_waitq
= queue
;
166 rpc_set_queued(task
);
168 dprintk("RPC: %5u added to queue %p \"%s\"\n",
169 task
->tk_pid
, queue
, rpc_qname(queue
));
173 * Remove request from a priority queue.
175 static void __rpc_remove_wait_queue_priority(struct rpc_task
*task
)
179 if (!list_empty(&task
->u
.tk_wait
.links
)) {
180 t
= list_entry(task
->u
.tk_wait
.links
.next
, struct rpc_task
, u
.tk_wait
.list
);
181 list_move(&t
->u
.tk_wait
.list
, &task
->u
.tk_wait
.list
);
182 list_splice_init(&task
->u
.tk_wait
.links
, &t
->u
.tk_wait
.links
);
184 list_del(&task
->u
.tk_wait
.list
);
188 * Remove request from queue.
189 * Note: must be called with spin lock held.
191 static void __rpc_remove_wait_queue(struct rpc_task
*task
)
193 struct rpc_wait_queue
*queue
;
194 queue
= task
->u
.tk_wait
.rpc_waitq
;
196 if (RPC_IS_PRIORITY(queue
))
197 __rpc_remove_wait_queue_priority(task
);
199 list_del(&task
->u
.tk_wait
.list
);
201 dprintk("RPC: %5u removed from queue %p \"%s\"\n",
202 task
->tk_pid
, queue
, rpc_qname(queue
));
205 static inline void rpc_set_waitqueue_priority(struct rpc_wait_queue
*queue
, int priority
)
207 queue
->priority
= priority
;
208 queue
->count
= 1 << (priority
* 2);
211 static inline void rpc_set_waitqueue_cookie(struct rpc_wait_queue
*queue
, unsigned long cookie
)
213 queue
->cookie
= cookie
;
214 queue
->nr
= RPC_BATCH_COUNT
;
217 static inline void rpc_reset_waitqueue_priority(struct rpc_wait_queue
*queue
)
219 rpc_set_waitqueue_priority(queue
, queue
->maxpriority
);
220 rpc_set_waitqueue_cookie(queue
, 0);
223 static void __rpc_init_priority_wait_queue(struct rpc_wait_queue
*queue
, const char *qname
, int maxprio
)
227 spin_lock_init(&queue
->lock
);
228 for (i
= 0; i
< ARRAY_SIZE(queue
->tasks
); i
++)
229 INIT_LIST_HEAD(&queue
->tasks
[i
]);
230 queue
->maxpriority
= maxprio
;
231 rpc_reset_waitqueue_priority(queue
);
237 void rpc_init_priority_wait_queue(struct rpc_wait_queue
*queue
, const char *qname
)
239 __rpc_init_priority_wait_queue(queue
, qname
, RPC_PRIORITY_HIGH
);
242 void rpc_init_wait_queue(struct rpc_wait_queue
*queue
, const char *qname
)
244 __rpc_init_priority_wait_queue(queue
, qname
, 0);
246 EXPORT_SYMBOL(rpc_init_wait_queue
);
248 static int rpc_wait_bit_interruptible(void *word
)
250 if (signal_pending(current
))
257 static void rpc_task_set_debuginfo(struct rpc_task
*task
)
259 static atomic_t rpc_pid
;
261 task
->tk_magic
= RPC_TASK_MAGIC_ID
;
262 task
->tk_pid
= atomic_inc_return(&rpc_pid
);
265 static inline void rpc_task_set_debuginfo(struct rpc_task
*task
)
270 static void rpc_set_active(struct rpc_task
*task
)
272 struct rpc_clnt
*clnt
;
273 if (test_and_set_bit(RPC_TASK_ACTIVE
, &task
->tk_runstate
) != 0)
275 rpc_task_set_debuginfo(task
);
276 /* Add to global list of all tasks */
277 clnt
= task
->tk_client
;
279 spin_lock(&clnt
->cl_lock
);
280 list_add_tail(&task
->tk_task
, &clnt
->cl_tasks
);
281 spin_unlock(&clnt
->cl_lock
);
286 * Mark an RPC call as having completed by clearing the 'active' bit
288 static void rpc_mark_complete_task(struct rpc_task
*task
)
290 smp_mb__before_clear_bit();
291 clear_bit(RPC_TASK_ACTIVE
, &task
->tk_runstate
);
292 smp_mb__after_clear_bit();
293 wake_up_bit(&task
->tk_runstate
, RPC_TASK_ACTIVE
);
297 * Allow callers to wait for completion of an RPC call
299 int __rpc_wait_for_completion_task(struct rpc_task
*task
, int (*action
)(void *))
302 action
= rpc_wait_bit_interruptible
;
303 return wait_on_bit(&task
->tk_runstate
, RPC_TASK_ACTIVE
,
304 action
, TASK_INTERRUPTIBLE
);
306 EXPORT_SYMBOL(__rpc_wait_for_completion_task
);
309 * Make an RPC task runnable.
311 * Note: If the task is ASYNC, this must be called with
312 * the spinlock held to protect the wait queue operation.
314 static void rpc_make_runnable(struct rpc_task
*task
)
316 BUG_ON(task
->tk_timeout_fn
);
317 rpc_clear_queued(task
);
318 if (rpc_test_and_set_running(task
))
320 /* We might have raced */
321 if (RPC_IS_QUEUED(task
)) {
322 rpc_clear_running(task
);
325 if (RPC_IS_ASYNC(task
)) {
328 INIT_WORK(&task
->u
.tk_work
, rpc_async_schedule
);
329 status
= queue_work(task
->tk_workqueue
, &task
->u
.tk_work
);
331 printk(KERN_WARNING
"RPC: failed to add task to queue: error: %d!\n", status
);
332 task
->tk_status
= status
;
336 wake_up_bit(&task
->tk_runstate
, RPC_TASK_QUEUED
);
340 * Prepare for sleeping on a wait queue.
341 * By always appending tasks to the list we ensure FIFO behavior.
342 * NB: An RPC task will only receive interrupt-driven events as long
343 * as it's on a wait queue.
345 static void __rpc_sleep_on(struct rpc_wait_queue
*q
, struct rpc_task
*task
,
346 rpc_action action
, rpc_action timer
)
348 dprintk("RPC: %5u sleep_on(queue \"%s\" time %lu)\n",
349 task
->tk_pid
, rpc_qname(q
), jiffies
);
351 if (!RPC_IS_ASYNC(task
) && !RPC_IS_ACTIVATED(task
)) {
352 printk(KERN_ERR
"RPC: Inactive synchronous task put to sleep!\n");
356 __rpc_add_wait_queue(q
, task
);
358 BUG_ON(task
->tk_callback
!= NULL
);
359 task
->tk_callback
= action
;
360 __rpc_add_timer(task
, timer
);
363 void rpc_sleep_on(struct rpc_wait_queue
*q
, struct rpc_task
*task
,
364 rpc_action action
, rpc_action timer
)
366 /* Mark the task as being activated if so needed */
367 rpc_set_active(task
);
370 * Protect the queue operations.
372 spin_lock_bh(&q
->lock
);
373 __rpc_sleep_on(q
, task
, action
, timer
);
374 spin_unlock_bh(&q
->lock
);
378 * __rpc_do_wake_up_task - wake up a single rpc_task
379 * @task: task to be woken up
381 * Caller must hold queue->lock, and have cleared the task queued flag.
383 static void __rpc_do_wake_up_task(struct rpc_task
*task
)
385 dprintk("RPC: %5u __rpc_wake_up_task (now %lu)\n",
386 task
->tk_pid
, jiffies
);
389 BUG_ON(task
->tk_magic
!= RPC_TASK_MAGIC_ID
);
391 /* Has the task been executed yet? If not, we cannot wake it up! */
392 if (!RPC_IS_ACTIVATED(task
)) {
393 printk(KERN_ERR
"RPC: Inactive task (%p) being woken up!\n", task
);
397 __rpc_disable_timer(task
);
398 __rpc_remove_wait_queue(task
);
400 rpc_make_runnable(task
);
402 dprintk("RPC: __rpc_wake_up_task done\n");
406 * Wake up the specified task
408 static void __rpc_wake_up_task(struct rpc_task
*task
)
410 if (rpc_start_wakeup(task
)) {
411 if (RPC_IS_QUEUED(task
))
412 __rpc_do_wake_up_task(task
);
413 rpc_finish_wakeup(task
);
418 * Default timeout handler if none specified by user
421 __rpc_default_timer(struct rpc_task
*task
)
423 dprintk("RPC: %5u timeout (default timer)\n", task
->tk_pid
);
424 task
->tk_status
= -ETIMEDOUT
;
425 rpc_wake_up_task(task
);
429 * Wake up the specified task
431 void rpc_wake_up_task(struct rpc_task
*task
)
434 if (rpc_start_wakeup(task
)) {
435 if (RPC_IS_QUEUED(task
)) {
436 struct rpc_wait_queue
*queue
= task
->u
.tk_wait
.rpc_waitq
;
438 /* Note: we're already in a bh-safe context */
439 spin_lock(&queue
->lock
);
440 __rpc_do_wake_up_task(task
);
441 spin_unlock(&queue
->lock
);
443 rpc_finish_wakeup(task
);
445 rcu_read_unlock_bh();
449 * Wake up the next task on a priority queue.
451 static struct rpc_task
* __rpc_wake_up_next_priority(struct rpc_wait_queue
*queue
)
454 struct rpc_task
*task
;
457 * Service a batch of tasks from a single cookie.
459 q
= &queue
->tasks
[queue
->priority
];
460 if (!list_empty(q
)) {
461 task
= list_entry(q
->next
, struct rpc_task
, u
.tk_wait
.list
);
462 if (queue
->cookie
== task
->tk_cookie
) {
465 list_move_tail(&task
->u
.tk_wait
.list
, q
);
468 * Check if we need to switch queues.
475 * Service the next queue.
478 if (q
== &queue
->tasks
[0])
479 q
= &queue
->tasks
[queue
->maxpriority
];
482 if (!list_empty(q
)) {
483 task
= list_entry(q
->next
, struct rpc_task
, u
.tk_wait
.list
);
486 } while (q
!= &queue
->tasks
[queue
->priority
]);
488 rpc_reset_waitqueue_priority(queue
);
492 rpc_set_waitqueue_priority(queue
, (unsigned int)(q
- &queue
->tasks
[0]));
494 rpc_set_waitqueue_cookie(queue
, task
->tk_cookie
);
496 __rpc_wake_up_task(task
);
501 * Wake up the next task on the wait queue.
503 struct rpc_task
* rpc_wake_up_next(struct rpc_wait_queue
*queue
)
505 struct rpc_task
*task
= NULL
;
507 dprintk("RPC: wake_up_next(%p \"%s\")\n",
508 queue
, rpc_qname(queue
));
510 spin_lock(&queue
->lock
);
511 if (RPC_IS_PRIORITY(queue
))
512 task
= __rpc_wake_up_next_priority(queue
);
514 task_for_first(task
, &queue
->tasks
[0])
515 __rpc_wake_up_task(task
);
517 spin_unlock(&queue
->lock
);
518 rcu_read_unlock_bh();
524 * rpc_wake_up - wake up all rpc_tasks
525 * @queue: rpc_wait_queue on which the tasks are sleeping
529 void rpc_wake_up(struct rpc_wait_queue
*queue
)
531 struct rpc_task
*task
, *next
;
532 struct list_head
*head
;
535 spin_lock(&queue
->lock
);
536 head
= &queue
->tasks
[queue
->maxpriority
];
538 list_for_each_entry_safe(task
, next
, head
, u
.tk_wait
.list
)
539 __rpc_wake_up_task(task
);
540 if (head
== &queue
->tasks
[0])
544 spin_unlock(&queue
->lock
);
545 rcu_read_unlock_bh();
549 * rpc_wake_up_status - wake up all rpc_tasks and set their status value.
550 * @queue: rpc_wait_queue on which the tasks are sleeping
551 * @status: status value to set
555 void rpc_wake_up_status(struct rpc_wait_queue
*queue
, int status
)
557 struct rpc_task
*task
, *next
;
558 struct list_head
*head
;
561 spin_lock(&queue
->lock
);
562 head
= &queue
->tasks
[queue
->maxpriority
];
564 list_for_each_entry_safe(task
, next
, head
, u
.tk_wait
.list
) {
565 task
->tk_status
= status
;
566 __rpc_wake_up_task(task
);
568 if (head
== &queue
->tasks
[0])
572 spin_unlock(&queue
->lock
);
573 rcu_read_unlock_bh();
576 static void __rpc_atrun(struct rpc_task
*task
)
578 rpc_wake_up_task(task
);
582 * Run a task at a later time
584 void rpc_delay(struct rpc_task
*task
, unsigned long delay
)
586 task
->tk_timeout
= delay
;
587 rpc_sleep_on(&delay_queue
, task
, NULL
, __rpc_atrun
);
591 * Helper to call task->tk_ops->rpc_call_prepare
593 static void rpc_prepare_task(struct rpc_task
*task
)
596 task
->tk_ops
->rpc_call_prepare(task
, task
->tk_calldata
);
601 * Helper that calls task->tk_ops->rpc_call_done if it exists
603 void rpc_exit_task(struct rpc_task
*task
)
605 task
->tk_action
= NULL
;
606 if (task
->tk_ops
->rpc_call_done
!= NULL
) {
608 task
->tk_ops
->rpc_call_done(task
, task
->tk_calldata
);
610 if (task
->tk_action
!= NULL
) {
611 WARN_ON(RPC_ASSASSINATED(task
));
612 /* Always release the RPC slot and buffer memory */
617 EXPORT_SYMBOL(rpc_exit_task
);
619 void rpc_release_calldata(const struct rpc_call_ops
*ops
, void *calldata
)
621 if (ops
->rpc_release
!= NULL
) {
623 ops
->rpc_release(calldata
);
629 * This is the RPC `scheduler' (or rather, the finite state machine).
631 static void __rpc_execute(struct rpc_task
*task
)
635 dprintk("RPC: %5u __rpc_execute flags=0x%x\n",
636 task
->tk_pid
, task
->tk_flags
);
638 BUG_ON(RPC_IS_QUEUED(task
));
642 * Garbage collection of pending timers...
644 rpc_delete_timer(task
);
647 * Execute any pending callback.
649 if (RPC_DO_CALLBACK(task
)) {
650 /* Define a callback save pointer */
651 void (*save_callback
)(struct rpc_task
*);
654 * If a callback exists, save it, reset it,
656 * The save is needed to stop from resetting
657 * another callback set within the callback handler
660 save_callback
=task
->tk_callback
;
661 task
->tk_callback
=NULL
;
666 * Perform the next FSM step.
667 * tk_action may be NULL when the task has been killed
670 if (!RPC_IS_QUEUED(task
)) {
671 if (task
->tk_action
== NULL
)
673 task
->tk_action(task
);
677 * Lockless check for whether task is sleeping or not.
679 if (!RPC_IS_QUEUED(task
))
681 rpc_clear_running(task
);
682 if (RPC_IS_ASYNC(task
)) {
683 /* Careful! we may have raced... */
684 if (RPC_IS_QUEUED(task
))
686 if (rpc_test_and_set_running(task
))
691 /* sync task: sleep here */
692 dprintk("RPC: %5u sync task going to sleep\n", task
->tk_pid
);
693 /* Note: Caller should be using rpc_clnt_sigmask() */
694 status
= out_of_line_wait_on_bit(&task
->tk_runstate
,
695 RPC_TASK_QUEUED
, rpc_wait_bit_interruptible
,
697 if (status
== -ERESTARTSYS
) {
699 * When a sync task receives a signal, it exits with
700 * -ERESTARTSYS. In order to catch any callbacks that
701 * clean up after sleeping on some queue, we don't
702 * break the loop here, but go around once more.
704 dprintk("RPC: %5u got signal\n", task
->tk_pid
);
705 task
->tk_flags
|= RPC_TASK_KILLED
;
706 rpc_exit(task
, -ERESTARTSYS
);
707 rpc_wake_up_task(task
);
709 rpc_set_running(task
);
710 dprintk("RPC: %5u sync task resuming\n", task
->tk_pid
);
713 dprintk("RPC: %5u return %d, status %d\n", task
->tk_pid
, status
,
715 /* Release all resources associated with the task */
716 rpc_release_task(task
);
720 * User-visible entry point to the scheduler.
722 * This may be called recursively if e.g. an async NFS task updates
723 * the attributes and finds that dirty pages must be flushed.
724 * NOTE: Upon exit of this function the task is guaranteed to be
725 * released. In particular note that tk_release() will have
726 * been called, so your task memory may have been freed.
728 void rpc_execute(struct rpc_task
*task
)
730 rpc_set_active(task
);
731 rpc_set_running(task
);
735 static void rpc_async_schedule(struct work_struct
*work
)
737 __rpc_execute(container_of(work
, struct rpc_task
, u
.tk_work
));
746 * rpc_malloc - allocate an RPC buffer
747 * @task: RPC task that will use this buffer
748 * @size: requested byte size
750 * To prevent rpciod from hanging, this allocator never sleeps,
751 * returning NULL if the request cannot be serviced immediately.
752 * The caller can arrange to sleep in a way that is safe for rpciod.
754 * Most requests are 'small' (under 2KiB) and can be serviced from a
755 * mempool, ensuring that NFS reads and writes can always proceed,
756 * and that there is good locality of reference for these buffers.
758 * In order to avoid memory starvation triggering more writebacks of
759 * NFS requests, we avoid using GFP_KERNEL.
761 void *rpc_malloc(struct rpc_task
*task
, size_t size
)
763 struct rpc_buffer
*buf
;
764 gfp_t gfp
= RPC_IS_SWAPPER(task
) ? GFP_ATOMIC
: GFP_NOWAIT
;
766 size
+= sizeof(struct rpc_buffer
);
767 if (size
<= RPC_BUFFER_MAXSIZE
)
768 buf
= mempool_alloc(rpc_buffer_mempool
, gfp
);
770 buf
= kmalloc(size
, gfp
);
776 dprintk("RPC: %5u allocated buffer of size %zu at %p\n",
777 task
->tk_pid
, size
, buf
);
780 EXPORT_SYMBOL_GPL(rpc_malloc
);
783 * rpc_free - free buffer allocated via rpc_malloc
784 * @buffer: buffer to free
787 void rpc_free(void *buffer
)
790 struct rpc_buffer
*buf
;
795 buf
= container_of(buffer
, struct rpc_buffer
, data
);
798 dprintk("RPC: freeing buffer of size %zu at %p\n",
801 if (size
<= RPC_BUFFER_MAXSIZE
)
802 mempool_free(buf
, rpc_buffer_mempool
);
806 EXPORT_SYMBOL_GPL(rpc_free
);
809 * Creation and deletion of RPC task structures
811 void rpc_init_task(struct rpc_task
*task
, struct rpc_clnt
*clnt
, int flags
, const struct rpc_call_ops
*tk_ops
, void *calldata
)
813 memset(task
, 0, sizeof(*task
));
814 setup_timer(&task
->tk_timer
, (void (*)(unsigned long))rpc_run_timer
,
815 (unsigned long)task
);
816 atomic_set(&task
->tk_count
, 1);
817 task
->tk_client
= clnt
;
818 task
->tk_flags
= flags
;
819 task
->tk_ops
= tk_ops
;
820 if (tk_ops
->rpc_call_prepare
!= NULL
)
821 task
->tk_action
= rpc_prepare_task
;
822 task
->tk_calldata
= calldata
;
823 INIT_LIST_HEAD(&task
->tk_task
);
825 /* Initialize retry counters */
826 task
->tk_garb_retry
= 2;
827 task
->tk_cred_retry
= 2;
829 task
->tk_priority
= RPC_PRIORITY_NORMAL
;
830 task
->tk_cookie
= (unsigned long)current
;
832 /* Initialize workqueue for async tasks */
833 task
->tk_workqueue
= rpciod_workqueue
;
836 kref_get(&clnt
->cl_kref
);
837 if (clnt
->cl_softrtry
)
838 task
->tk_flags
|= RPC_TASK_SOFT
;
840 task
->tk_flags
|= RPC_TASK_NOINTR
;
843 BUG_ON(task
->tk_ops
== NULL
);
845 /* starting timestamp */
846 task
->tk_start
= jiffies
;
848 dprintk("RPC: new task initialized, procpid %u\n",
849 task_pid_nr(current
));
852 static struct rpc_task
*
855 return (struct rpc_task
*)mempool_alloc(rpc_task_mempool
, GFP_NOFS
);
858 static void rpc_free_task(struct rcu_head
*rcu
)
860 struct rpc_task
*task
= container_of(rcu
, struct rpc_task
, u
.tk_rcu
);
861 dprintk("RPC: %5u freeing task\n", task
->tk_pid
);
862 mempool_free(task
, rpc_task_mempool
);
866 * Create a new task for the specified client.
868 struct rpc_task
*rpc_new_task(struct rpc_clnt
*clnt
, int flags
, const struct rpc_call_ops
*tk_ops
, void *calldata
)
870 struct rpc_task
*task
;
872 task
= rpc_alloc_task();
876 rpc_init_task(task
, clnt
, flags
, tk_ops
, calldata
);
878 dprintk("RPC: allocated task %p\n", task
);
879 task
->tk_flags
|= RPC_TASK_DYNAMIC
;
885 void rpc_put_task(struct rpc_task
*task
)
887 const struct rpc_call_ops
*tk_ops
= task
->tk_ops
;
888 void *calldata
= task
->tk_calldata
;
890 if (!atomic_dec_and_test(&task
->tk_count
))
892 /* Release resources */
895 if (task
->tk_msg
.rpc_cred
)
896 rpcauth_unbindcred(task
);
897 if (task
->tk_client
) {
898 rpc_release_client(task
->tk_client
);
899 task
->tk_client
= NULL
;
901 if (task
->tk_flags
& RPC_TASK_DYNAMIC
)
902 call_rcu_bh(&task
->u
.tk_rcu
, rpc_free_task
);
903 rpc_release_calldata(tk_ops
, calldata
);
905 EXPORT_SYMBOL(rpc_put_task
);
907 static void rpc_release_task(struct rpc_task
*task
)
910 BUG_ON(task
->tk_magic
!= RPC_TASK_MAGIC_ID
);
912 dprintk("RPC: %5u release task\n", task
->tk_pid
);
914 if (!list_empty(&task
->tk_task
)) {
915 struct rpc_clnt
*clnt
= task
->tk_client
;
916 /* Remove from client task list */
917 spin_lock(&clnt
->cl_lock
);
918 list_del(&task
->tk_task
);
919 spin_unlock(&clnt
->cl_lock
);
921 BUG_ON (RPC_IS_QUEUED(task
));
923 /* Synchronously delete any running timer */
924 rpc_delete_timer(task
);
929 /* Wake up anyone who is waiting for task completion */
930 rpc_mark_complete_task(task
);
936 * Kill all tasks for the given client.
937 * XXX: kill their descendants as well?
939 void rpc_killall_tasks(struct rpc_clnt
*clnt
)
941 struct rpc_task
*rovr
;
944 if (list_empty(&clnt
->cl_tasks
))
946 dprintk("RPC: killing all tasks for client %p\n", clnt
);
948 * Spin lock all_tasks to prevent changes...
950 spin_lock(&clnt
->cl_lock
);
951 list_for_each_entry(rovr
, &clnt
->cl_tasks
, tk_task
) {
952 if (! RPC_IS_ACTIVATED(rovr
))
954 if (!(rovr
->tk_flags
& RPC_TASK_KILLED
)) {
955 rovr
->tk_flags
|= RPC_TASK_KILLED
;
956 rpc_exit(rovr
, -EIO
);
957 rpc_wake_up_task(rovr
);
960 spin_unlock(&clnt
->cl_lock
);
965 return try_module_get(THIS_MODULE
) ? 0 : -EINVAL
;
968 void rpciod_down(void)
970 module_put(THIS_MODULE
);
974 * Start up the rpciod workqueue.
976 static int rpciod_start(void)
978 struct workqueue_struct
*wq
;
981 * Create the rpciod thread and wait for it to start.
983 dprintk("RPC: creating workqueue rpciod\n");
984 wq
= create_workqueue("rpciod");
985 rpciod_workqueue
= wq
;
986 return rpciod_workqueue
!= NULL
;
989 static void rpciod_stop(void)
991 struct workqueue_struct
*wq
= NULL
;
993 if (rpciod_workqueue
== NULL
)
995 dprintk("RPC: destroying workqueue rpciod\n");
997 wq
= rpciod_workqueue
;
998 rpciod_workqueue
= NULL
;
999 destroy_workqueue(wq
);
1003 rpc_destroy_mempool(void)
1006 if (rpc_buffer_mempool
)
1007 mempool_destroy(rpc_buffer_mempool
);
1008 if (rpc_task_mempool
)
1009 mempool_destroy(rpc_task_mempool
);
1011 kmem_cache_destroy(rpc_task_slabp
);
1012 if (rpc_buffer_slabp
)
1013 kmem_cache_destroy(rpc_buffer_slabp
);
1017 rpc_init_mempool(void)
1019 rpc_task_slabp
= kmem_cache_create("rpc_tasks",
1020 sizeof(struct rpc_task
),
1021 0, SLAB_HWCACHE_ALIGN
,
1023 if (!rpc_task_slabp
)
1025 rpc_buffer_slabp
= kmem_cache_create("rpc_buffers",
1027 0, SLAB_HWCACHE_ALIGN
,
1029 if (!rpc_buffer_slabp
)
1031 rpc_task_mempool
= mempool_create_slab_pool(RPC_TASK_POOLSIZE
,
1033 if (!rpc_task_mempool
)
1035 rpc_buffer_mempool
= mempool_create_slab_pool(RPC_BUFFER_POOLSIZE
,
1037 if (!rpc_buffer_mempool
)
1039 if (!rpciod_start())
1043 rpc_destroy_mempool();