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();