2005-04-16 16:20:36 -06:00
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/*
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* linux/net/sunrpc/sched.c
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*
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* Scheduling for synchronous and asynchronous RPC requests.
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*
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* Copyright (C) 1996 Olaf Kirch, <okir@monad.swb.de>
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*
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* TCP NFS related read + write fixes
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* (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
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*/
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/interrupt.h>
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#include <linux/slab.h>
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#include <linux/mempool.h>
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#include <linux/smp.h>
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#include <linux/smp_lock.h>
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#include <linux/spinlock.h>
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#include <linux/sunrpc/clnt.h>
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#include <linux/sunrpc/xprt.h>
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#ifdef RPC_DEBUG
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#define RPCDBG_FACILITY RPCDBG_SCHED
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#define RPC_TASK_MAGIC_ID 0xf00baa
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static int rpc_task_id;
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#endif
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/*
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* RPC slabs and memory pools
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*/
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#define RPC_BUFFER_MAXSIZE (2048)
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#define RPC_BUFFER_POOLSIZE (8)
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#define RPC_TASK_POOLSIZE (8)
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2005-08-26 13:05:31 -06:00
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static kmem_cache_t *rpc_task_slabp __read_mostly;
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static kmem_cache_t *rpc_buffer_slabp __read_mostly;
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static mempool_t *rpc_task_mempool __read_mostly;
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static mempool_t *rpc_buffer_mempool __read_mostly;
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2005-04-16 16:20:36 -06:00
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static void __rpc_default_timer(struct rpc_task *task);
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static void rpciod_killall(void);
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static void rpc_async_schedule(void *);
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/*
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* RPC tasks that create another task (e.g. for contacting the portmapper)
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* will wait on this queue for their child's completion
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*/
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static RPC_WAITQ(childq, "childq");
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/*
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* RPC tasks sit here while waiting for conditions to improve.
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*/
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static RPC_WAITQ(delay_queue, "delayq");
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/*
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* All RPC tasks are linked into this list
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*/
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static LIST_HEAD(all_tasks);
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/*
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* rpciod-related stuff
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*/
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static DECLARE_MUTEX(rpciod_sema);
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static unsigned int rpciod_users;
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2006-03-20 11:44:08 -07:00
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struct workqueue_struct *rpciod_workqueue;
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2005-04-16 16:20:36 -06:00
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/*
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* Spinlock for other critical sections of code.
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*/
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static DEFINE_SPINLOCK(rpc_sched_lock);
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/*
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* Disable the timer for a given RPC task. Should be called with
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* queue->lock and bh_disabled in order to avoid races within
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* rpc_run_timer().
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*/
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static inline void
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__rpc_disable_timer(struct rpc_task *task)
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{
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dprintk("RPC: %4d disabling timer\n", task->tk_pid);
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task->tk_timeout_fn = NULL;
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task->tk_timeout = 0;
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}
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/*
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* Run a timeout function.
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* We use the callback in order to allow __rpc_wake_up_task()
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* and friends to disable the timer synchronously on SMP systems
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* without calling del_timer_sync(). The latter could cause a
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* deadlock if called while we're holding spinlocks...
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*/
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static void rpc_run_timer(struct rpc_task *task)
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{
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void (*callback)(struct rpc_task *);
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callback = task->tk_timeout_fn;
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task->tk_timeout_fn = NULL;
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if (callback && RPC_IS_QUEUED(task)) {
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dprintk("RPC: %4d running timer\n", task->tk_pid);
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callback(task);
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}
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smp_mb__before_clear_bit();
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clear_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate);
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smp_mb__after_clear_bit();
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}
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/*
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* Set up a timer for the current task.
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*/
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static inline void
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__rpc_add_timer(struct rpc_task *task, rpc_action timer)
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{
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if (!task->tk_timeout)
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return;
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dprintk("RPC: %4d setting alarm for %lu ms\n",
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task->tk_pid, task->tk_timeout * 1000 / HZ);
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if (timer)
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task->tk_timeout_fn = timer;
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else
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task->tk_timeout_fn = __rpc_default_timer;
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set_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate);
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mod_timer(&task->tk_timer, jiffies + task->tk_timeout);
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}
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/*
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* Delete any timer for the current task. Because we use del_timer_sync(),
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* this function should never be called while holding queue->lock.
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*/
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static void
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rpc_delete_timer(struct rpc_task *task)
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{
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if (RPC_IS_QUEUED(task))
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return;
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if (test_and_clear_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate)) {
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del_singleshot_timer_sync(&task->tk_timer);
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dprintk("RPC: %4d deleting timer\n", task->tk_pid);
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}
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}
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/*
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* Add new request to a priority queue.
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*/
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static void __rpc_add_wait_queue_priority(struct rpc_wait_queue *queue, struct rpc_task *task)
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{
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struct list_head *q;
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struct rpc_task *t;
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INIT_LIST_HEAD(&task->u.tk_wait.links);
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q = &queue->tasks[task->tk_priority];
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if (unlikely(task->tk_priority > queue->maxpriority))
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q = &queue->tasks[queue->maxpriority];
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list_for_each_entry(t, q, u.tk_wait.list) {
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if (t->tk_cookie == task->tk_cookie) {
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list_add_tail(&task->u.tk_wait.list, &t->u.tk_wait.links);
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return;
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}
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}
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list_add_tail(&task->u.tk_wait.list, q);
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}
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/*
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* Add new request to wait queue.
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*
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* Swapper tasks always get inserted at the head of the queue.
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* This should avoid many nasty memory deadlocks and hopefully
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* improve overall performance.
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* Everyone else gets appended to the queue to ensure proper FIFO behavior.
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*/
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static void __rpc_add_wait_queue(struct rpc_wait_queue *queue, struct rpc_task *task)
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{
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BUG_ON (RPC_IS_QUEUED(task));
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if (RPC_IS_PRIORITY(queue))
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__rpc_add_wait_queue_priority(queue, task);
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else if (RPC_IS_SWAPPER(task))
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list_add(&task->u.tk_wait.list, &queue->tasks[0]);
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else
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list_add_tail(&task->u.tk_wait.list, &queue->tasks[0]);
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task->u.tk_wait.rpc_waitq = queue;
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2006-03-20 11:44:15 -07:00
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queue->qlen++;
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2005-04-16 16:20:36 -06:00
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rpc_set_queued(task);
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dprintk("RPC: %4d added to queue %p \"%s\"\n",
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task->tk_pid, queue, rpc_qname(queue));
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}
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/*
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* Remove request from a priority queue.
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*/
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static void __rpc_remove_wait_queue_priority(struct rpc_task *task)
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{
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struct rpc_task *t;
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if (!list_empty(&task->u.tk_wait.links)) {
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t = list_entry(task->u.tk_wait.links.next, struct rpc_task, u.tk_wait.list);
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list_move(&t->u.tk_wait.list, &task->u.tk_wait.list);
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list_splice_init(&task->u.tk_wait.links, &t->u.tk_wait.links);
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}
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list_del(&task->u.tk_wait.list);
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}
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/*
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* Remove request from queue.
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* Note: must be called with spin lock held.
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*/
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static void __rpc_remove_wait_queue(struct rpc_task *task)
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{
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struct rpc_wait_queue *queue;
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queue = task->u.tk_wait.rpc_waitq;
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if (RPC_IS_PRIORITY(queue))
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__rpc_remove_wait_queue_priority(task);
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else
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list_del(&task->u.tk_wait.list);
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2006-03-20 11:44:15 -07:00
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queue->qlen--;
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2005-04-16 16:20:36 -06:00
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dprintk("RPC: %4d removed from queue %p \"%s\"\n",
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task->tk_pid, queue, rpc_qname(queue));
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}
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static inline void rpc_set_waitqueue_priority(struct rpc_wait_queue *queue, int priority)
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{
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queue->priority = priority;
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queue->count = 1 << (priority * 2);
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}
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static inline void rpc_set_waitqueue_cookie(struct rpc_wait_queue *queue, unsigned long cookie)
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{
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queue->cookie = cookie;
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queue->nr = RPC_BATCH_COUNT;
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}
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static inline void rpc_reset_waitqueue_priority(struct rpc_wait_queue *queue)
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{
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rpc_set_waitqueue_priority(queue, queue->maxpriority);
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rpc_set_waitqueue_cookie(queue, 0);
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}
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static void __rpc_init_priority_wait_queue(struct rpc_wait_queue *queue, const char *qname, int maxprio)
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{
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int i;
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spin_lock_init(&queue->lock);
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for (i = 0; i < ARRAY_SIZE(queue->tasks); i++)
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INIT_LIST_HEAD(&queue->tasks[i]);
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queue->maxpriority = maxprio;
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rpc_reset_waitqueue_priority(queue);
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#ifdef RPC_DEBUG
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queue->name = qname;
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#endif
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}
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void rpc_init_priority_wait_queue(struct rpc_wait_queue *queue, const char *qname)
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{
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__rpc_init_priority_wait_queue(queue, qname, RPC_PRIORITY_HIGH);
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}
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void rpc_init_wait_queue(struct rpc_wait_queue *queue, const char *qname)
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{
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__rpc_init_priority_wait_queue(queue, qname, 0);
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}
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EXPORT_SYMBOL(rpc_init_wait_queue);
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2006-01-03 01:55:06 -07:00
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static int rpc_wait_bit_interruptible(void *word)
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{
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if (signal_pending(current))
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return -ERESTARTSYS;
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schedule();
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return 0;
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}
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/*
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* Mark an RPC call as having completed by clearing the 'active' bit
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*/
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static inline void rpc_mark_complete_task(struct rpc_task *task)
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{
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rpc_clear_active(task);
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wake_up_bit(&task->tk_runstate, RPC_TASK_ACTIVE);
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}
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/*
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* Allow callers to wait for completion of an RPC call
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*/
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int __rpc_wait_for_completion_task(struct rpc_task *task, int (*action)(void *))
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{
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if (action == NULL)
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action = rpc_wait_bit_interruptible;
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return wait_on_bit(&task->tk_runstate, RPC_TASK_ACTIVE,
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action, TASK_INTERRUPTIBLE);
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}
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EXPORT_SYMBOL(__rpc_wait_for_completion_task);
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2005-04-16 16:20:36 -06:00
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/*
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* Make an RPC task runnable.
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*
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* Note: If the task is ASYNC, this must be called with
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* the spinlock held to protect the wait queue operation.
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*/
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static void rpc_make_runnable(struct rpc_task *task)
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{
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int do_ret;
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BUG_ON(task->tk_timeout_fn);
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do_ret = rpc_test_and_set_running(task);
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rpc_clear_queued(task);
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if (do_ret)
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return;
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if (RPC_IS_ASYNC(task)) {
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int status;
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INIT_WORK(&task->u.tk_work, rpc_async_schedule, (void *)task);
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status = queue_work(task->tk_workqueue, &task->u.tk_work);
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if (status < 0) {
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printk(KERN_WARNING "RPC: failed to add task to queue: error: %d!\n", status);
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task->tk_status = status;
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return;
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}
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} else
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2005-06-22 11:16:21 -06:00
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wake_up_bit(&task->tk_runstate, RPC_TASK_QUEUED);
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2005-04-16 16:20:36 -06:00
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}
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/*
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* Place a newly initialized task on the workqueue.
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*/
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static inline void
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rpc_schedule_run(struct rpc_task *task)
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{
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2006-01-03 01:55:06 -07:00
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rpc_set_active(task);
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2005-04-16 16:20:36 -06:00
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rpc_make_runnable(task);
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}
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/*
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* Prepare for sleeping on a wait queue.
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* By always appending tasks to the list we ensure FIFO behavior.
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* NB: An RPC task will only receive interrupt-driven events as long
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* as it's on a wait queue.
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*/
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static void __rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
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rpc_action action, rpc_action timer)
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{
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dprintk("RPC: %4d sleep_on(queue \"%s\" time %ld)\n", task->tk_pid,
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rpc_qname(q), jiffies);
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if (!RPC_IS_ASYNC(task) && !RPC_IS_ACTIVATED(task)) {
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printk(KERN_ERR "RPC: Inactive synchronous task put to sleep!\n");
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return;
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}
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/* Mark the task as being activated if so needed */
|
2006-01-03 01:55:06 -07:00
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rpc_set_active(task);
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2005-04-16 16:20:36 -06:00
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__rpc_add_wait_queue(q, task);
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BUG_ON(task->tk_callback != NULL);
|
|
|
|
task->tk_callback = action;
|
|
|
|
__rpc_add_timer(task, timer);
|
|
|
|
}
|
|
|
|
|
|
|
|
void rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
|
|
|
|
rpc_action action, rpc_action timer)
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* Protect the queue operations.
|
|
|
|
*/
|
|
|
|
spin_lock_bh(&q->lock);
|
|
|
|
__rpc_sleep_on(q, task, action, timer);
|
|
|
|
spin_unlock_bh(&q->lock);
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* __rpc_do_wake_up_task - wake up a single rpc_task
|
|
|
|
* @task: task to be woken up
|
|
|
|
*
|
|
|
|
* Caller must hold queue->lock, and have cleared the task queued flag.
|
|
|
|
*/
|
|
|
|
static void __rpc_do_wake_up_task(struct rpc_task *task)
|
|
|
|
{
|
|
|
|
dprintk("RPC: %4d __rpc_wake_up_task (now %ld)\n", task->tk_pid, jiffies);
|
|
|
|
|
|
|
|
#ifdef RPC_DEBUG
|
|
|
|
BUG_ON(task->tk_magic != RPC_TASK_MAGIC_ID);
|
|
|
|
#endif
|
|
|
|
/* Has the task been executed yet? If not, we cannot wake it up! */
|
|
|
|
if (!RPC_IS_ACTIVATED(task)) {
|
|
|
|
printk(KERN_ERR "RPC: Inactive task (%p) being woken up!\n", task);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
__rpc_disable_timer(task);
|
|
|
|
__rpc_remove_wait_queue(task);
|
|
|
|
|
|
|
|
rpc_make_runnable(task);
|
|
|
|
|
|
|
|
dprintk("RPC: __rpc_wake_up_task done\n");
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Wake up the specified task
|
|
|
|
*/
|
|
|
|
static void __rpc_wake_up_task(struct rpc_task *task)
|
|
|
|
{
|
|
|
|
if (rpc_start_wakeup(task)) {
|
|
|
|
if (RPC_IS_QUEUED(task))
|
|
|
|
__rpc_do_wake_up_task(task);
|
|
|
|
rpc_finish_wakeup(task);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Default timeout handler if none specified by user
|
|
|
|
*/
|
|
|
|
static void
|
|
|
|
__rpc_default_timer(struct rpc_task *task)
|
|
|
|
{
|
|
|
|
dprintk("RPC: %d timeout (default timer)\n", task->tk_pid);
|
|
|
|
task->tk_status = -ETIMEDOUT;
|
|
|
|
rpc_wake_up_task(task);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Wake up the specified task
|
|
|
|
*/
|
|
|
|
void rpc_wake_up_task(struct rpc_task *task)
|
|
|
|
{
|
|
|
|
if (rpc_start_wakeup(task)) {
|
|
|
|
if (RPC_IS_QUEUED(task)) {
|
|
|
|
struct rpc_wait_queue *queue = task->u.tk_wait.rpc_waitq;
|
|
|
|
|
|
|
|
spin_lock_bh(&queue->lock);
|
|
|
|
__rpc_do_wake_up_task(task);
|
|
|
|
spin_unlock_bh(&queue->lock);
|
|
|
|
}
|
|
|
|
rpc_finish_wakeup(task);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Wake up the next task on a priority queue.
|
|
|
|
*/
|
|
|
|
static struct rpc_task * __rpc_wake_up_next_priority(struct rpc_wait_queue *queue)
|
|
|
|
{
|
|
|
|
struct list_head *q;
|
|
|
|
struct rpc_task *task;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Service a batch of tasks from a single cookie.
|
|
|
|
*/
|
|
|
|
q = &queue->tasks[queue->priority];
|
|
|
|
if (!list_empty(q)) {
|
|
|
|
task = list_entry(q->next, struct rpc_task, u.tk_wait.list);
|
|
|
|
if (queue->cookie == task->tk_cookie) {
|
|
|
|
if (--queue->nr)
|
|
|
|
goto out;
|
|
|
|
list_move_tail(&task->u.tk_wait.list, q);
|
|
|
|
}
|
|
|
|
/*
|
|
|
|
* Check if we need to switch queues.
|
|
|
|
*/
|
|
|
|
if (--queue->count)
|
|
|
|
goto new_cookie;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Service the next queue.
|
|
|
|
*/
|
|
|
|
do {
|
|
|
|
if (q == &queue->tasks[0])
|
|
|
|
q = &queue->tasks[queue->maxpriority];
|
|
|
|
else
|
|
|
|
q = q - 1;
|
|
|
|
if (!list_empty(q)) {
|
|
|
|
task = list_entry(q->next, struct rpc_task, u.tk_wait.list);
|
|
|
|
goto new_queue;
|
|
|
|
}
|
|
|
|
} while (q != &queue->tasks[queue->priority]);
|
|
|
|
|
|
|
|
rpc_reset_waitqueue_priority(queue);
|
|
|
|
return NULL;
|
|
|
|
|
|
|
|
new_queue:
|
|
|
|
rpc_set_waitqueue_priority(queue, (unsigned int)(q - &queue->tasks[0]));
|
|
|
|
new_cookie:
|
|
|
|
rpc_set_waitqueue_cookie(queue, task->tk_cookie);
|
|
|
|
out:
|
|
|
|
__rpc_wake_up_task(task);
|
|
|
|
return task;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Wake up the next task on the wait queue.
|
|
|
|
*/
|
|
|
|
struct rpc_task * rpc_wake_up_next(struct rpc_wait_queue *queue)
|
|
|
|
{
|
|
|
|
struct rpc_task *task = NULL;
|
|
|
|
|
|
|
|
dprintk("RPC: wake_up_next(%p \"%s\")\n", queue, rpc_qname(queue));
|
|
|
|
spin_lock_bh(&queue->lock);
|
|
|
|
if (RPC_IS_PRIORITY(queue))
|
|
|
|
task = __rpc_wake_up_next_priority(queue);
|
|
|
|
else {
|
|
|
|
task_for_first(task, &queue->tasks[0])
|
|
|
|
__rpc_wake_up_task(task);
|
|
|
|
}
|
|
|
|
spin_unlock_bh(&queue->lock);
|
|
|
|
|
|
|
|
return task;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* rpc_wake_up - wake up all rpc_tasks
|
|
|
|
* @queue: rpc_wait_queue on which the tasks are sleeping
|
|
|
|
*
|
|
|
|
* Grabs queue->lock
|
|
|
|
*/
|
|
|
|
void rpc_wake_up(struct rpc_wait_queue *queue)
|
|
|
|
{
|
2006-03-13 22:20:48 -07:00
|
|
|
struct rpc_task *task, *next;
|
2005-04-16 16:20:36 -06:00
|
|
|
struct list_head *head;
|
2006-03-13 22:20:48 -07:00
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
spin_lock_bh(&queue->lock);
|
|
|
|
head = &queue->tasks[queue->maxpriority];
|
|
|
|
for (;;) {
|
2006-03-13 22:20:48 -07:00
|
|
|
list_for_each_entry_safe(task, next, head, u.tk_wait.list)
|
2005-04-16 16:20:36 -06:00
|
|
|
__rpc_wake_up_task(task);
|
|
|
|
if (head == &queue->tasks[0])
|
|
|
|
break;
|
|
|
|
head--;
|
|
|
|
}
|
|
|
|
spin_unlock_bh(&queue->lock);
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* rpc_wake_up_status - wake up all rpc_tasks and set their status value.
|
|
|
|
* @queue: rpc_wait_queue on which the tasks are sleeping
|
|
|
|
* @status: status value to set
|
|
|
|
*
|
|
|
|
* Grabs queue->lock
|
|
|
|
*/
|
|
|
|
void rpc_wake_up_status(struct rpc_wait_queue *queue, int status)
|
|
|
|
{
|
2006-03-13 22:20:48 -07:00
|
|
|
struct rpc_task *task, *next;
|
2005-04-16 16:20:36 -06:00
|
|
|
struct list_head *head;
|
|
|
|
|
|
|
|
spin_lock_bh(&queue->lock);
|
|
|
|
head = &queue->tasks[queue->maxpriority];
|
|
|
|
for (;;) {
|
2006-03-13 22:20:48 -07:00
|
|
|
list_for_each_entry_safe(task, next, head, u.tk_wait.list) {
|
2005-04-16 16:20:36 -06:00
|
|
|
task->tk_status = status;
|
|
|
|
__rpc_wake_up_task(task);
|
|
|
|
}
|
|
|
|
if (head == &queue->tasks[0])
|
|
|
|
break;
|
|
|
|
head--;
|
|
|
|
}
|
|
|
|
spin_unlock_bh(&queue->lock);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Run a task at a later time
|
|
|
|
*/
|
|
|
|
static void __rpc_atrun(struct rpc_task *);
|
|
|
|
void
|
|
|
|
rpc_delay(struct rpc_task *task, unsigned long delay)
|
|
|
|
{
|
|
|
|
task->tk_timeout = delay;
|
|
|
|
rpc_sleep_on(&delay_queue, task, NULL, __rpc_atrun);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void
|
|
|
|
__rpc_atrun(struct rpc_task *task)
|
|
|
|
{
|
|
|
|
task->tk_status = 0;
|
|
|
|
rpc_wake_up_task(task);
|
|
|
|
}
|
|
|
|
|
2006-01-03 01:55:05 -07:00
|
|
|
/*
|
|
|
|
* Helper to call task->tk_ops->rpc_call_prepare
|
|
|
|
*/
|
|
|
|
static void rpc_prepare_task(struct rpc_task *task)
|
|
|
|
{
|
|
|
|
task->tk_ops->rpc_call_prepare(task, task->tk_calldata);
|
|
|
|
}
|
|
|
|
|
2005-06-22 11:16:19 -06:00
|
|
|
/*
|
2006-01-03 01:55:04 -07:00
|
|
|
* Helper that calls task->tk_ops->rpc_call_done if it exists
|
2005-06-22 11:16:19 -06:00
|
|
|
*/
|
2006-01-03 01:55:03 -07:00
|
|
|
void rpc_exit_task(struct rpc_task *task)
|
2005-06-22 11:16:19 -06:00
|
|
|
{
|
2006-01-03 01:55:03 -07:00
|
|
|
task->tk_action = NULL;
|
2006-01-03 01:55:04 -07:00
|
|
|
if (task->tk_ops->rpc_call_done != NULL) {
|
|
|
|
task->tk_ops->rpc_call_done(task, task->tk_calldata);
|
2005-06-22 11:16:19 -06:00
|
|
|
if (task->tk_action != NULL) {
|
2006-01-03 01:55:03 -07:00
|
|
|
WARN_ON(RPC_ASSASSINATED(task));
|
|
|
|
/* Always release the RPC slot and buffer memory */
|
|
|
|
xprt_release(task);
|
2005-06-22 11:16:19 -06:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
2006-01-03 01:55:03 -07:00
|
|
|
EXPORT_SYMBOL(rpc_exit_task);
|
2005-06-22 11:16:19 -06:00
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/*
|
|
|
|
* This is the RPC `scheduler' (or rather, the finite state machine).
|
|
|
|
*/
|
|
|
|
static int __rpc_execute(struct rpc_task *task)
|
|
|
|
{
|
|
|
|
int status = 0;
|
|
|
|
|
|
|
|
dprintk("RPC: %4d rpc_execute flgs %x\n",
|
|
|
|
task->tk_pid, task->tk_flags);
|
|
|
|
|
|
|
|
BUG_ON(RPC_IS_QUEUED(task));
|
|
|
|
|
2005-06-22 11:16:19 -06:00
|
|
|
for (;;) {
|
2005-04-16 16:20:36 -06:00
|
|
|
/*
|
|
|
|
* Garbage collection of pending timers...
|
|
|
|
*/
|
|
|
|
rpc_delete_timer(task);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Execute any pending callback.
|
|
|
|
*/
|
|
|
|
if (RPC_DO_CALLBACK(task)) {
|
|
|
|
/* Define a callback save pointer */
|
|
|
|
void (*save_callback)(struct rpc_task *);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If a callback exists, save it, reset it,
|
|
|
|
* call it.
|
|
|
|
* The save is needed to stop from resetting
|
|
|
|
* another callback set within the callback handler
|
|
|
|
* - Dave
|
|
|
|
*/
|
|
|
|
save_callback=task->tk_callback;
|
|
|
|
task->tk_callback=NULL;
|
|
|
|
lock_kernel();
|
|
|
|
save_callback(task);
|
|
|
|
unlock_kernel();
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Perform the next FSM step.
|
|
|
|
* tk_action may be NULL when the task has been killed
|
|
|
|
* by someone else.
|
|
|
|
*/
|
|
|
|
if (!RPC_IS_QUEUED(task)) {
|
2006-01-03 01:55:03 -07:00
|
|
|
if (task->tk_action == NULL)
|
2005-04-16 16:20:36 -06:00
|
|
|
break;
|
2006-01-03 01:55:03 -07:00
|
|
|
lock_kernel();
|
|
|
|
task->tk_action(task);
|
|
|
|
unlock_kernel();
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Lockless check for whether task is sleeping or not.
|
|
|
|
*/
|
|
|
|
if (!RPC_IS_QUEUED(task))
|
|
|
|
continue;
|
|
|
|
rpc_clear_running(task);
|
|
|
|
if (RPC_IS_ASYNC(task)) {
|
|
|
|
/* Careful! we may have raced... */
|
|
|
|
if (RPC_IS_QUEUED(task))
|
|
|
|
return 0;
|
|
|
|
if (rpc_test_and_set_running(task))
|
|
|
|
return 0;
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* sync task: sleep here */
|
|
|
|
dprintk("RPC: %4d sync task going to sleep\n", task->tk_pid);
|
2005-06-22 11:16:21 -06:00
|
|
|
/* Note: Caller should be using rpc_clnt_sigmask() */
|
|
|
|
status = out_of_line_wait_on_bit(&task->tk_runstate,
|
|
|
|
RPC_TASK_QUEUED, rpc_wait_bit_interruptible,
|
|
|
|
TASK_INTERRUPTIBLE);
|
|
|
|
if (status == -ERESTARTSYS) {
|
2005-04-16 16:20:36 -06:00
|
|
|
/*
|
|
|
|
* When a sync task receives a signal, it exits with
|
|
|
|
* -ERESTARTSYS. In order to catch any callbacks that
|
|
|
|
* clean up after sleeping on some queue, we don't
|
|
|
|
* break the loop here, but go around once more.
|
|
|
|
*/
|
2005-06-22 11:16:21 -06:00
|
|
|
dprintk("RPC: %4d got signal\n", task->tk_pid);
|
|
|
|
task->tk_flags |= RPC_TASK_KILLED;
|
|
|
|
rpc_exit(task, -ERESTARTSYS);
|
|
|
|
rpc_wake_up_task(task);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
rpc_set_running(task);
|
|
|
|
dprintk("RPC: %4d sync task resuming\n", task->tk_pid);
|
|
|
|
}
|
|
|
|
|
2006-01-03 01:55:10 -07:00
|
|
|
dprintk("RPC: %4d, return %d, status %d\n", task->tk_pid, status, task->tk_status);
|
2006-01-03 01:55:06 -07:00
|
|
|
/* Wake up anyone who is waiting for task completion */
|
|
|
|
rpc_mark_complete_task(task);
|
2005-04-16 16:20:36 -06:00
|
|
|
/* Release all resources associated with the task */
|
|
|
|
rpc_release_task(task);
|
|
|
|
return status;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* User-visible entry point to the scheduler.
|
|
|
|
*
|
|
|
|
* This may be called recursively if e.g. an async NFS task updates
|
|
|
|
* the attributes and finds that dirty pages must be flushed.
|
|
|
|
* NOTE: Upon exit of this function the task is guaranteed to be
|
|
|
|
* released. In particular note that tk_release() will have
|
|
|
|
* been called, so your task memory may have been freed.
|
|
|
|
*/
|
|
|
|
int
|
|
|
|
rpc_execute(struct rpc_task *task)
|
|
|
|
{
|
2006-01-03 01:55:06 -07:00
|
|
|
rpc_set_active(task);
|
2005-04-16 16:20:36 -06:00
|
|
|
rpc_set_running(task);
|
|
|
|
return __rpc_execute(task);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void rpc_async_schedule(void *arg)
|
|
|
|
{
|
|
|
|
__rpc_execute((struct rpc_task *)arg);
|
|
|
|
}
|
|
|
|
|
2006-01-03 01:55:49 -07:00
|
|
|
/**
|
|
|
|
* rpc_malloc - allocate an RPC buffer
|
|
|
|
* @task: RPC task that will use this buffer
|
|
|
|
* @size: requested byte size
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
|
|
|
* We try to ensure that some NFS reads and writes can always proceed
|
|
|
|
* by using a mempool when allocating 'small' buffers.
|
|
|
|
* In order to avoid memory starvation triggering more writebacks of
|
|
|
|
* NFS requests, we use GFP_NOFS rather than GFP_KERNEL.
|
|
|
|
*/
|
2006-01-03 01:55:49 -07:00
|
|
|
void * rpc_malloc(struct rpc_task *task, size_t size)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2006-01-03 01:55:49 -07:00
|
|
|
struct rpc_rqst *req = task->tk_rqstp;
|
2005-10-07 00:46:04 -06:00
|
|
|
gfp_t gfp;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
if (task->tk_flags & RPC_TASK_SWAPPER)
|
|
|
|
gfp = GFP_ATOMIC;
|
|
|
|
else
|
|
|
|
gfp = GFP_NOFS;
|
|
|
|
|
|
|
|
if (size > RPC_BUFFER_MAXSIZE) {
|
2006-01-03 01:55:49 -07:00
|
|
|
req->rq_buffer = kmalloc(size, gfp);
|
|
|
|
if (req->rq_buffer)
|
|
|
|
req->rq_bufsize = size;
|
2005-04-16 16:20:36 -06:00
|
|
|
} else {
|
2006-01-03 01:55:49 -07:00
|
|
|
req->rq_buffer = mempool_alloc(rpc_buffer_mempool, gfp);
|
|
|
|
if (req->rq_buffer)
|
|
|
|
req->rq_bufsize = RPC_BUFFER_MAXSIZE;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2006-01-03 01:55:49 -07:00
|
|
|
return req->rq_buffer;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
2006-01-03 01:55:49 -07:00
|
|
|
/**
|
|
|
|
* rpc_free - free buffer allocated via rpc_malloc
|
|
|
|
* @task: RPC task with a buffer to be freed
|
|
|
|
*
|
|
|
|
*/
|
|
|
|
void rpc_free(struct rpc_task *task)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2006-01-03 01:55:49 -07:00
|
|
|
struct rpc_rqst *req = task->tk_rqstp;
|
|
|
|
|
|
|
|
if (req->rq_buffer) {
|
|
|
|
if (req->rq_bufsize == RPC_BUFFER_MAXSIZE)
|
|
|
|
mempool_free(req->rq_buffer, rpc_buffer_mempool);
|
2005-04-16 16:20:36 -06:00
|
|
|
else
|
2006-01-03 01:55:49 -07:00
|
|
|
kfree(req->rq_buffer);
|
|
|
|
req->rq_buffer = NULL;
|
|
|
|
req->rq_bufsize = 0;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Creation and deletion of RPC task structures
|
|
|
|
*/
|
2006-01-03 01:55:04 -07:00
|
|
|
void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt, int flags, const struct rpc_call_ops *tk_ops, void *calldata)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
memset(task, 0, sizeof(*task));
|
|
|
|
init_timer(&task->tk_timer);
|
|
|
|
task->tk_timer.data = (unsigned long) task;
|
|
|
|
task->tk_timer.function = (void (*)(unsigned long)) rpc_run_timer;
|
2006-01-03 01:55:06 -07:00
|
|
|
atomic_set(&task->tk_count, 1);
|
2005-04-16 16:20:36 -06:00
|
|
|
task->tk_client = clnt;
|
|
|
|
task->tk_flags = flags;
|
2006-01-03 01:55:04 -07:00
|
|
|
task->tk_ops = tk_ops;
|
2006-01-03 01:55:05 -07:00
|
|
|
if (tk_ops->rpc_call_prepare != NULL)
|
|
|
|
task->tk_action = rpc_prepare_task;
|
2006-01-03 01:55:04 -07:00
|
|
|
task->tk_calldata = calldata;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/* Initialize retry counters */
|
|
|
|
task->tk_garb_retry = 2;
|
|
|
|
task->tk_cred_retry = 2;
|
|
|
|
|
|
|
|
task->tk_priority = RPC_PRIORITY_NORMAL;
|
|
|
|
task->tk_cookie = (unsigned long)current;
|
|
|
|
|
|
|
|
/* Initialize workqueue for async tasks */
|
|
|
|
task->tk_workqueue = rpciod_workqueue;
|
|
|
|
|
|
|
|
if (clnt) {
|
|
|
|
atomic_inc(&clnt->cl_users);
|
|
|
|
if (clnt->cl_softrtry)
|
|
|
|
task->tk_flags |= RPC_TASK_SOFT;
|
|
|
|
if (!clnt->cl_intr)
|
|
|
|
task->tk_flags |= RPC_TASK_NOINTR;
|
|
|
|
}
|
|
|
|
|
|
|
|
#ifdef RPC_DEBUG
|
|
|
|
task->tk_magic = RPC_TASK_MAGIC_ID;
|
|
|
|
task->tk_pid = rpc_task_id++;
|
|
|
|
#endif
|
|
|
|
/* Add to global list of all tasks */
|
|
|
|
spin_lock(&rpc_sched_lock);
|
|
|
|
list_add_tail(&task->tk_task, &all_tasks);
|
|
|
|
spin_unlock(&rpc_sched_lock);
|
|
|
|
|
2006-01-03 01:55:04 -07:00
|
|
|
BUG_ON(task->tk_ops == NULL);
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
dprintk("RPC: %4d new task procpid %d\n", task->tk_pid,
|
|
|
|
current->pid);
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct rpc_task *
|
|
|
|
rpc_alloc_task(void)
|
|
|
|
{
|
|
|
|
return (struct rpc_task *)mempool_alloc(rpc_task_mempool, GFP_NOFS);
|
|
|
|
}
|
|
|
|
|
2006-01-03 01:55:04 -07:00
|
|
|
static void rpc_free_task(struct rpc_task *task)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
dprintk("RPC: %4d freeing task\n", task->tk_pid);
|
|
|
|
mempool_free(task, rpc_task_mempool);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Create a new task for the specified client. We have to
|
|
|
|
* clean up after an allocation failure, as the client may
|
|
|
|
* have specified "oneshot".
|
|
|
|
*/
|
2006-01-03 01:55:04 -07:00
|
|
|
struct rpc_task *rpc_new_task(struct rpc_clnt *clnt, int flags, const struct rpc_call_ops *tk_ops, void *calldata)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
struct rpc_task *task;
|
|
|
|
|
|
|
|
task = rpc_alloc_task();
|
|
|
|
if (!task)
|
|
|
|
goto cleanup;
|
|
|
|
|
2006-01-03 01:55:04 -07:00
|
|
|
rpc_init_task(task, clnt, flags, tk_ops, calldata);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
dprintk("RPC: %4d allocated task\n", task->tk_pid);
|
|
|
|
task->tk_flags |= RPC_TASK_DYNAMIC;
|
|
|
|
out:
|
|
|
|
return task;
|
|
|
|
|
|
|
|
cleanup:
|
|
|
|
/* Check whether to release the client */
|
|
|
|
if (clnt) {
|
|
|
|
printk("rpc_new_task: failed, users=%d, oneshot=%d\n",
|
|
|
|
atomic_read(&clnt->cl_users), clnt->cl_oneshot);
|
|
|
|
atomic_inc(&clnt->cl_users); /* pretend we were used ... */
|
|
|
|
rpc_release_client(clnt);
|
|
|
|
}
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
void rpc_release_task(struct rpc_task *task)
|
|
|
|
{
|
2006-01-03 01:55:04 -07:00
|
|
|
const struct rpc_call_ops *tk_ops = task->tk_ops;
|
|
|
|
void *calldata = task->tk_calldata;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
#ifdef RPC_DEBUG
|
|
|
|
BUG_ON(task->tk_magic != RPC_TASK_MAGIC_ID);
|
|
|
|
#endif
|
2006-01-03 01:55:06 -07:00
|
|
|
if (!atomic_dec_and_test(&task->tk_count))
|
|
|
|
return;
|
|
|
|
dprintk("RPC: %4d release task\n", task->tk_pid);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/* Remove from global task list */
|
|
|
|
spin_lock(&rpc_sched_lock);
|
|
|
|
list_del(&task->tk_task);
|
|
|
|
spin_unlock(&rpc_sched_lock);
|
|
|
|
|
|
|
|
BUG_ON (RPC_IS_QUEUED(task));
|
|
|
|
|
|
|
|
/* Synchronously delete any running timer */
|
|
|
|
rpc_delete_timer(task);
|
|
|
|
|
|
|
|
/* Release resources */
|
|
|
|
if (task->tk_rqstp)
|
|
|
|
xprt_release(task);
|
|
|
|
if (task->tk_msg.rpc_cred)
|
|
|
|
rpcauth_unbindcred(task);
|
|
|
|
if (task->tk_client) {
|
|
|
|
rpc_release_client(task->tk_client);
|
|
|
|
task->tk_client = NULL;
|
|
|
|
}
|
|
|
|
|
|
|
|
#ifdef RPC_DEBUG
|
|
|
|
task->tk_magic = 0;
|
|
|
|
#endif
|
2006-01-03 01:55:04 -07:00
|
|
|
if (task->tk_flags & RPC_TASK_DYNAMIC)
|
|
|
|
rpc_free_task(task);
|
|
|
|
if (tk_ops->rpc_release)
|
|
|
|
tk_ops->rpc_release(calldata);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
2006-01-03 01:55:06 -07:00
|
|
|
/**
|
|
|
|
* rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
|
2006-02-01 04:06:56 -07:00
|
|
|
* @clnt: pointer to RPC client
|
|
|
|
* @flags: RPC flags
|
|
|
|
* @ops: RPC call ops
|
|
|
|
* @data: user call data
|
2006-01-03 01:55:06 -07:00
|
|
|
*/
|
|
|
|
struct rpc_task *rpc_run_task(struct rpc_clnt *clnt, int flags,
|
|
|
|
const struct rpc_call_ops *ops,
|
|
|
|
void *data)
|
|
|
|
{
|
|
|
|
struct rpc_task *task;
|
|
|
|
task = rpc_new_task(clnt, flags, ops, data);
|
|
|
|
if (task == NULL)
|
|
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
atomic_inc(&task->tk_count);
|
|
|
|
rpc_execute(task);
|
|
|
|
return task;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(rpc_run_task);
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
|
|
|
* rpc_find_parent - find the parent of a child task.
|
|
|
|
* @child: child task
|
2006-02-01 04:06:56 -07:00
|
|
|
* @parent: parent task
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
|
|
|
* Checks that the parent task is still sleeping on the
|
|
|
|
* queue 'childq'. If so returns a pointer to the parent.
|
|
|
|
* Upon failure returns NULL.
|
|
|
|
*
|
|
|
|
* Caller must hold childq.lock
|
|
|
|
*/
|
2006-01-03 01:55:04 -07:00
|
|
|
static inline struct rpc_task *rpc_find_parent(struct rpc_task *child, struct rpc_task *parent)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2006-01-03 01:55:04 -07:00
|
|
|
struct rpc_task *task;
|
2005-04-16 16:20:36 -06:00
|
|
|
struct list_head *le;
|
|
|
|
|
|
|
|
task_for_each(task, le, &childq.tasks[0])
|
|
|
|
if (task == parent)
|
|
|
|
return parent;
|
|
|
|
|
|
|
|
return NULL;
|
|
|
|
}
|
|
|
|
|
2006-01-03 01:55:04 -07:00
|
|
|
static void rpc_child_exit(struct rpc_task *child, void *calldata)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
struct rpc_task *parent;
|
|
|
|
|
|
|
|
spin_lock_bh(&childq.lock);
|
2006-01-03 01:55:04 -07:00
|
|
|
if ((parent = rpc_find_parent(child, calldata)) != NULL) {
|
2005-04-16 16:20:36 -06:00
|
|
|
parent->tk_status = child->tk_status;
|
|
|
|
__rpc_wake_up_task(parent);
|
|
|
|
}
|
|
|
|
spin_unlock_bh(&childq.lock);
|
|
|
|
}
|
|
|
|
|
2006-01-03 01:55:04 -07:00
|
|
|
static const struct rpc_call_ops rpc_child_ops = {
|
|
|
|
.rpc_call_done = rpc_child_exit,
|
|
|
|
};
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/*
|
|
|
|
* Note: rpc_new_task releases the client after a failure.
|
|
|
|
*/
|
|
|
|
struct rpc_task *
|
|
|
|
rpc_new_child(struct rpc_clnt *clnt, struct rpc_task *parent)
|
|
|
|
{
|
|
|
|
struct rpc_task *task;
|
|
|
|
|
2006-01-03 01:55:04 -07:00
|
|
|
task = rpc_new_task(clnt, RPC_TASK_ASYNC | RPC_TASK_CHILD, &rpc_child_ops, parent);
|
2005-04-16 16:20:36 -06:00
|
|
|
if (!task)
|
|
|
|
goto fail;
|
|
|
|
return task;
|
|
|
|
|
|
|
|
fail:
|
|
|
|
parent->tk_status = -ENOMEM;
|
|
|
|
return NULL;
|
|
|
|
}
|
|
|
|
|
|
|
|
void rpc_run_child(struct rpc_task *task, struct rpc_task *child, rpc_action func)
|
|
|
|
{
|
|
|
|
spin_lock_bh(&childq.lock);
|
|
|
|
/* N.B. Is it possible for the child to have already finished? */
|
|
|
|
__rpc_sleep_on(&childq, task, func, NULL);
|
|
|
|
rpc_schedule_run(child);
|
|
|
|
spin_unlock_bh(&childq.lock);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Kill all tasks for the given client.
|
|
|
|
* XXX: kill their descendants as well?
|
|
|
|
*/
|
|
|
|
void rpc_killall_tasks(struct rpc_clnt *clnt)
|
|
|
|
{
|
|
|
|
struct rpc_task *rovr;
|
|
|
|
struct list_head *le;
|
|
|
|
|
|
|
|
dprintk("RPC: killing all tasks for client %p\n", clnt);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Spin lock all_tasks to prevent changes...
|
|
|
|
*/
|
|
|
|
spin_lock(&rpc_sched_lock);
|
|
|
|
alltask_for_each(rovr, le, &all_tasks) {
|
|
|
|
if (! RPC_IS_ACTIVATED(rovr))
|
|
|
|
continue;
|
|
|
|
if (!clnt || rovr->tk_client == clnt) {
|
|
|
|
rovr->tk_flags |= RPC_TASK_KILLED;
|
|
|
|
rpc_exit(rovr, -EIO);
|
|
|
|
rpc_wake_up_task(rovr);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
spin_unlock(&rpc_sched_lock);
|
|
|
|
}
|
|
|
|
|
|
|
|
static DECLARE_MUTEX_LOCKED(rpciod_running);
|
|
|
|
|
|
|
|
static void rpciod_killall(void)
|
|
|
|
{
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
while (!list_empty(&all_tasks)) {
|
|
|
|
clear_thread_flag(TIF_SIGPENDING);
|
|
|
|
rpc_killall_tasks(NULL);
|
|
|
|
flush_workqueue(rpciod_workqueue);
|
|
|
|
if (!list_empty(&all_tasks)) {
|
|
|
|
dprintk("rpciod_killall: waiting for tasks to exit\n");
|
|
|
|
yield();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
spin_lock_irqsave(¤t->sighand->siglock, flags);
|
|
|
|
recalc_sigpending();
|
|
|
|
spin_unlock_irqrestore(¤t->sighand->siglock, flags);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Start up the rpciod process if it's not already running.
|
|
|
|
*/
|
|
|
|
int
|
|
|
|
rpciod_up(void)
|
|
|
|
{
|
|
|
|
struct workqueue_struct *wq;
|
|
|
|
int error = 0;
|
|
|
|
|
|
|
|
down(&rpciod_sema);
|
|
|
|
dprintk("rpciod_up: users %d\n", rpciod_users);
|
|
|
|
rpciod_users++;
|
|
|
|
if (rpciod_workqueue)
|
|
|
|
goto out;
|
|
|
|
/*
|
|
|
|
* If there's no pid, we should be the first user.
|
|
|
|
*/
|
|
|
|
if (rpciod_users > 1)
|
|
|
|
printk(KERN_WARNING "rpciod_up: no workqueue, %d users??\n", rpciod_users);
|
|
|
|
/*
|
|
|
|
* Create the rpciod thread and wait for it to start.
|
|
|
|
*/
|
|
|
|
error = -ENOMEM;
|
|
|
|
wq = create_workqueue("rpciod");
|
|
|
|
if (wq == NULL) {
|
|
|
|
printk(KERN_WARNING "rpciod_up: create workqueue failed, error=%d\n", error);
|
|
|
|
rpciod_users--;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
rpciod_workqueue = wq;
|
|
|
|
error = 0;
|
|
|
|
out:
|
|
|
|
up(&rpciod_sema);
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
|
|
|
|
void
|
|
|
|
rpciod_down(void)
|
|
|
|
{
|
|
|
|
down(&rpciod_sema);
|
|
|
|
dprintk("rpciod_down sema %d\n", rpciod_users);
|
|
|
|
if (rpciod_users) {
|
|
|
|
if (--rpciod_users)
|
|
|
|
goto out;
|
|
|
|
} else
|
|
|
|
printk(KERN_WARNING "rpciod_down: no users??\n");
|
|
|
|
|
|
|
|
if (!rpciod_workqueue) {
|
|
|
|
dprintk("rpciod_down: Nothing to do!\n");
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
rpciod_killall();
|
|
|
|
|
|
|
|
destroy_workqueue(rpciod_workqueue);
|
|
|
|
rpciod_workqueue = NULL;
|
|
|
|
out:
|
|
|
|
up(&rpciod_sema);
|
|
|
|
}
|
|
|
|
|
|
|
|
#ifdef RPC_DEBUG
|
|
|
|
void rpc_show_tasks(void)
|
|
|
|
{
|
|
|
|
struct list_head *le;
|
|
|
|
struct rpc_task *t;
|
|
|
|
|
|
|
|
spin_lock(&rpc_sched_lock);
|
|
|
|
if (list_empty(&all_tasks)) {
|
|
|
|
spin_unlock(&rpc_sched_lock);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
|
2006-01-03 01:55:04 -07:00
|
|
|
"-rpcwait -action- ---ops--\n");
|
2005-04-16 16:20:36 -06:00
|
|
|
alltask_for_each(t, le, &all_tasks) {
|
|
|
|
const char *rpc_waitq = "none";
|
|
|
|
|
|
|
|
if (RPC_IS_QUEUED(t))
|
|
|
|
rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
|
|
|
|
|
|
|
|
printk("%05d %04d %04x %06d %8p %6d %8p %08ld %8s %8p %8p\n",
|
|
|
|
t->tk_pid,
|
|
|
|
(t->tk_msg.rpc_proc ? t->tk_msg.rpc_proc->p_proc : -1),
|
|
|
|
t->tk_flags, t->tk_status,
|
|
|
|
t->tk_client,
|
|
|
|
(t->tk_client ? t->tk_client->cl_prog : 0),
|
|
|
|
t->tk_rqstp, t->tk_timeout,
|
|
|
|
rpc_waitq,
|
2006-01-03 01:55:04 -07:00
|
|
|
t->tk_action, t->tk_ops);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
spin_unlock(&rpc_sched_lock);
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
void
|
|
|
|
rpc_destroy_mempool(void)
|
|
|
|
{
|
|
|
|
if (rpc_buffer_mempool)
|
|
|
|
mempool_destroy(rpc_buffer_mempool);
|
|
|
|
if (rpc_task_mempool)
|
|
|
|
mempool_destroy(rpc_task_mempool);
|
|
|
|
if (rpc_task_slabp && kmem_cache_destroy(rpc_task_slabp))
|
|
|
|
printk(KERN_INFO "rpc_task: not all structures were freed\n");
|
|
|
|
if (rpc_buffer_slabp && kmem_cache_destroy(rpc_buffer_slabp))
|
|
|
|
printk(KERN_INFO "rpc_buffers: not all structures were freed\n");
|
|
|
|
}
|
|
|
|
|
|
|
|
int
|
|
|
|
rpc_init_mempool(void)
|
|
|
|
{
|
|
|
|
rpc_task_slabp = kmem_cache_create("rpc_tasks",
|
|
|
|
sizeof(struct rpc_task),
|
|
|
|
0, SLAB_HWCACHE_ALIGN,
|
|
|
|
NULL, NULL);
|
|
|
|
if (!rpc_task_slabp)
|
|
|
|
goto err_nomem;
|
|
|
|
rpc_buffer_slabp = kmem_cache_create("rpc_buffers",
|
|
|
|
RPC_BUFFER_MAXSIZE,
|
|
|
|
0, SLAB_HWCACHE_ALIGN,
|
|
|
|
NULL, NULL);
|
|
|
|
if (!rpc_buffer_slabp)
|
|
|
|
goto err_nomem;
|
|
|
|
rpc_task_mempool = mempool_create(RPC_TASK_POOLSIZE,
|
|
|
|
mempool_alloc_slab,
|
|
|
|
mempool_free_slab,
|
|
|
|
rpc_task_slabp);
|
|
|
|
if (!rpc_task_mempool)
|
|
|
|
goto err_nomem;
|
|
|
|
rpc_buffer_mempool = mempool_create(RPC_BUFFER_POOLSIZE,
|
|
|
|
mempool_alloc_slab,
|
|
|
|
mempool_free_slab,
|
|
|
|
rpc_buffer_slabp);
|
|
|
|
if (!rpc_buffer_mempool)
|
|
|
|
goto err_nomem;
|
|
|
|
return 0;
|
|
|
|
err_nomem:
|
|
|
|
rpc_destroy_mempool();
|
|
|
|
return -ENOMEM;
|
|
|
|
}
|