#include <linux/slab.h>
#include <linux/mempool.h>
#include <linux/smp.h>
-#include <linux/smp_lock.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include <linux/sunrpc/clnt.h>
+#include "sunrpc.h"
+
#ifdef RPC_DEBUG
#define RPCDBG_FACILITY RPCDBG_SCHED
#define RPC_TASK_MAGIC_ID 0xf00baa
static mempool_t *rpc_task_mempool __read_mostly;
static mempool_t *rpc_buffer_mempool __read_mostly;
-static void __rpc_default_timer(struct rpc_task *task);
static void rpc_async_schedule(struct work_struct *);
static void rpc_release_task(struct rpc_task *task);
+static void __rpc_queue_timer_fn(unsigned long ptr);
/*
* RPC tasks sit here while waiting for conditions to improve.
* queue->lock and bh_disabled in order to avoid races within
* rpc_run_timer().
*/
-static inline void
-__rpc_disable_timer(struct rpc_task *task)
+static void
+__rpc_disable_timer(struct rpc_wait_queue *queue, struct rpc_task *task)
{
+ if (task->tk_timeout == 0)
+ return;
dprintk("RPC: %5u disabling timer\n", task->tk_pid);
- task->tk_timeout_fn = NULL;
task->tk_timeout = 0;
+ list_del(&task->u.tk_wait.timer_list);
+ if (list_empty(&queue->timer_list.list))
+ del_timer(&queue->timer_list.timer);
}
-/*
- * Run a timeout function.
- * We use the callback in order to allow __rpc_wake_up_task()
- * and friends to disable the timer synchronously on SMP systems
- * without calling del_timer_sync(). The latter could cause a
- * deadlock if called while we're holding spinlocks...
- */
-static void rpc_run_timer(struct rpc_task *task)
+static void
+rpc_set_queue_timer(struct rpc_wait_queue *queue, unsigned long expires)
{
- void (*callback)(struct rpc_task *);
-
- callback = task->tk_timeout_fn;
- task->tk_timeout_fn = NULL;
- if (callback && RPC_IS_QUEUED(task)) {
- dprintk("RPC: %5u running timer\n", task->tk_pid);
- callback(task);
- }
- smp_mb__before_clear_bit();
- clear_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate);
- smp_mb__after_clear_bit();
+ queue->timer_list.expires = expires;
+ mod_timer(&queue->timer_list.timer, expires);
}
/*
* Set up a timer for the current task.
*/
-static inline void
-__rpc_add_timer(struct rpc_task *task, rpc_action timer)
+static void
+__rpc_add_timer(struct rpc_wait_queue *queue, struct rpc_task *task)
{
if (!task->tk_timeout)
return;
dprintk("RPC: %5u setting alarm for %lu ms\n",
task->tk_pid, task->tk_timeout * 1000 / HZ);
- if (timer)
- task->tk_timeout_fn = timer;
- else
- task->tk_timeout_fn = __rpc_default_timer;
- set_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate);
- mod_timer(&task->tk_timer, jiffies + task->tk_timeout);
-}
-
-/*
- * Delete any timer for the current task. Because we use del_timer_sync(),
- * this function should never be called while holding queue->lock.
- */
-static void
-rpc_delete_timer(struct rpc_task *task)
-{
- if (RPC_IS_QUEUED(task))
- return;
- if (test_and_clear_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate)) {
- del_singleshot_timer_sync(&task->tk_timer);
- dprintk("RPC: %5u deleting timer\n", task->tk_pid);
- }
+ task->u.tk_wait.expires = jiffies + task->tk_timeout;
+ if (list_empty(&queue->timer_list.list) || time_before(task->u.tk_wait.expires, queue->timer_list.expires))
+ rpc_set_queue_timer(queue, task->u.tk_wait.expires);
+ list_add(&task->u.tk_wait.timer_list, &queue->timer_list.list);
}
/*
list_add(&task->u.tk_wait.list, &queue->tasks[0]);
else
list_add_tail(&task->u.tk_wait.list, &queue->tasks[0]);
- task->u.tk_wait.rpc_waitq = queue;
+ task->tk_waitqueue = queue;
queue->qlen++;
rpc_set_queued(task);
list_move(&t->u.tk_wait.list, &task->u.tk_wait.list);
list_splice_init(&task->u.tk_wait.links, &t->u.tk_wait.links);
}
- list_del(&task->u.tk_wait.list);
}
/*
* Remove request from queue.
* Note: must be called with spin lock held.
*/
-static void __rpc_remove_wait_queue(struct rpc_task *task)
+static void __rpc_remove_wait_queue(struct rpc_wait_queue *queue, struct rpc_task *task)
{
- struct rpc_wait_queue *queue;
- queue = task->u.tk_wait.rpc_waitq;
-
+ __rpc_disable_timer(queue, task);
if (RPC_IS_PRIORITY(queue))
__rpc_remove_wait_queue_priority(task);
- else
- list_del(&task->u.tk_wait.list);
+ list_del(&task->u.tk_wait.list);
queue->qlen--;
dprintk("RPC: %5u removed from queue %p \"%s\"\n",
task->tk_pid, queue, rpc_qname(queue));
INIT_LIST_HEAD(&queue->tasks[i]);
queue->maxpriority = nr_queues - 1;
rpc_reset_waitqueue_priority(queue);
+ queue->qlen = 0;
+ setup_timer(&queue->timer_list.timer, __rpc_queue_timer_fn, (unsigned long)queue);
+ INIT_LIST_HEAD(&queue->timer_list.list);
#ifdef RPC_DEBUG
queue->name = qname;
#endif
{
__rpc_init_priority_wait_queue(queue, qname, RPC_NR_PRIORITY);
}
+EXPORT_SYMBOL_GPL(rpc_init_priority_wait_queue);
void rpc_init_wait_queue(struct rpc_wait_queue *queue, const char *qname)
{
}
EXPORT_SYMBOL_GPL(rpc_init_wait_queue);
+void rpc_destroy_wait_queue(struct rpc_wait_queue *queue)
+{
+ del_timer_sync(&queue->timer_list.timer);
+}
+EXPORT_SYMBOL_GPL(rpc_destroy_wait_queue);
+
static int rpc_wait_bit_killable(void *word)
{
if (fatal_signal_pending(current))
*/
static void rpc_make_runnable(struct rpc_task *task)
{
- BUG_ON(task->tk_timeout_fn);
rpc_clear_queued(task);
if (rpc_test_and_set_running(task))
return;
- /* We might have raced */
- if (RPC_IS_QUEUED(task)) {
- rpc_clear_running(task);
- return;
- }
if (RPC_IS_ASYNC(task)) {
int status;
* as it's on a wait queue.
*/
static void __rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
- rpc_action action, rpc_action timer)
+ rpc_action action)
{
dprintk("RPC: %5u sleep_on(queue \"%s\" time %lu)\n",
task->tk_pid, rpc_qname(q), jiffies);
BUG_ON(task->tk_callback != NULL);
task->tk_callback = action;
- __rpc_add_timer(task, timer);
+ __rpc_add_timer(q, task);
}
void rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
- rpc_action action, rpc_action timer)
+ rpc_action action)
{
/* Mark the task as being activated if so needed */
rpc_set_active(task);
* Protect the queue operations.
*/
spin_lock_bh(&q->lock);
- __rpc_sleep_on(q, task, action, timer);
+ __rpc_sleep_on(q, task, action);
spin_unlock_bh(&q->lock);
}
EXPORT_SYMBOL_GPL(rpc_sleep_on);
/**
* __rpc_do_wake_up_task - wake up a single rpc_task
+ * @queue: wait queue
* @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)
+static void __rpc_do_wake_up_task(struct rpc_wait_queue *queue, struct rpc_task *task)
{
dprintk("RPC: %5u __rpc_wake_up_task (now %lu)\n",
task->tk_pid, jiffies);
return;
}
- __rpc_disable_timer(task);
- __rpc_remove_wait_queue(task);
+ __rpc_remove_wait_queue(queue, task);
rpc_make_runnable(task);
}
/*
- * Wake up the specified task
+ * Wake up a queued task while the queue lock is being held
*/
-static void __rpc_wake_up_task(struct rpc_task *task)
+static void rpc_wake_up_task_queue_locked(struct rpc_wait_queue *queue, struct rpc_task *task)
{
- if (rpc_start_wakeup(task)) {
- if (RPC_IS_QUEUED(task))
- __rpc_do_wake_up_task(task);
- rpc_finish_wakeup(task);
- }
+ if (RPC_IS_QUEUED(task) && task->tk_waitqueue == queue)
+ __rpc_do_wake_up_task(queue, task);
}
/*
- * Default timeout handler if none specified by user
+ * Tests whether rpc queue is empty
*/
-static void
-__rpc_default_timer(struct rpc_task *task)
+int rpc_queue_empty(struct rpc_wait_queue *queue)
{
- dprintk("RPC: %5u timeout (default timer)\n", task->tk_pid);
- task->tk_status = -ETIMEDOUT;
- rpc_wake_up_task(task);
+ int res;
+
+ spin_lock_bh(&queue->lock);
+ res = queue->qlen;
+ spin_unlock_bh(&queue->lock);
+ return (res == 0);
+}
+EXPORT_SYMBOL_GPL(rpc_queue_empty);
+
+/*
+ * Wake up a task on a specific queue
+ */
+void rpc_wake_up_queued_task(struct rpc_wait_queue *queue, struct rpc_task *task)
+{
+ spin_lock_bh(&queue->lock);
+ rpc_wake_up_task_queue_locked(queue, task);
+ spin_unlock_bh(&queue->lock);
}
+EXPORT_SYMBOL_GPL(rpc_wake_up_queued_task);
/*
* Wake up the specified task
*/
-void rpc_wake_up_task(struct rpc_task *task)
+static void rpc_wake_up_task(struct rpc_task *task)
{
- rcu_read_lock_bh();
- if (rpc_start_wakeup(task)) {
- if (RPC_IS_QUEUED(task)) {
- struct rpc_wait_queue *queue = task->u.tk_wait.rpc_waitq;
-
- /* Note: we're already in a bh-safe context */
- spin_lock(&queue->lock);
- __rpc_do_wake_up_task(task);
- spin_unlock(&queue->lock);
- }
- rpc_finish_wakeup(task);
- }
- rcu_read_unlock_bh();
+ rpc_wake_up_queued_task(task->tk_waitqueue, task);
}
-EXPORT_SYMBOL_GPL(rpc_wake_up_task);
/*
* Wake up the next task on a priority queue.
new_owner:
rpc_set_waitqueue_owner(queue, task->tk_owner);
out:
- __rpc_wake_up_task(task);
+ rpc_wake_up_task_queue_locked(queue, task);
return task;
}
dprintk("RPC: wake_up_next(%p \"%s\")\n",
queue, rpc_qname(queue));
- rcu_read_lock_bh();
- spin_lock(&queue->lock);
+ 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);
+ rpc_wake_up_task_queue_locked(queue, task);
}
- spin_unlock(&queue->lock);
- rcu_read_unlock_bh();
+ spin_unlock_bh(&queue->lock);
return task;
}
struct rpc_task *task, *next;
struct list_head *head;
- rcu_read_lock_bh();
- spin_lock(&queue->lock);
+ spin_lock_bh(&queue->lock);
head = &queue->tasks[queue->maxpriority];
for (;;) {
list_for_each_entry_safe(task, next, head, u.tk_wait.list)
- __rpc_wake_up_task(task);
+ rpc_wake_up_task_queue_locked(queue, task);
if (head == &queue->tasks[0])
break;
head--;
}
- spin_unlock(&queue->lock);
- rcu_read_unlock_bh();
+ spin_unlock_bh(&queue->lock);
}
EXPORT_SYMBOL_GPL(rpc_wake_up);
struct rpc_task *task, *next;
struct list_head *head;
- rcu_read_lock_bh();
- spin_lock(&queue->lock);
+ spin_lock_bh(&queue->lock);
head = &queue->tasks[queue->maxpriority];
for (;;) {
list_for_each_entry_safe(task, next, head, u.tk_wait.list) {
task->tk_status = status;
- __rpc_wake_up_task(task);
+ rpc_wake_up_task_queue_locked(queue, task);
}
if (head == &queue->tasks[0])
break;
head--;
}
- spin_unlock(&queue->lock);
- rcu_read_unlock_bh();
+ spin_unlock_bh(&queue->lock);
}
EXPORT_SYMBOL_GPL(rpc_wake_up_status);
+static void __rpc_queue_timer_fn(unsigned long ptr)
+{
+ struct rpc_wait_queue *queue = (struct rpc_wait_queue *)ptr;
+ struct rpc_task *task, *n;
+ unsigned long expires, now, timeo;
+
+ spin_lock(&queue->lock);
+ expires = now = jiffies;
+ list_for_each_entry_safe(task, n, &queue->timer_list.list, u.tk_wait.timer_list) {
+ timeo = task->u.tk_wait.expires;
+ if (time_after_eq(now, timeo)) {
+ dprintk("RPC: %5u timeout\n", task->tk_pid);
+ task->tk_status = -ETIMEDOUT;
+ rpc_wake_up_task_queue_locked(queue, task);
+ continue;
+ }
+ if (expires == now || time_after(expires, timeo))
+ expires = timeo;
+ }
+ if (!list_empty(&queue->timer_list.list))
+ rpc_set_queue_timer(queue, expires);
+ spin_unlock(&queue->lock);
+}
+
static void __rpc_atrun(struct rpc_task *task)
{
- rpc_wake_up_task(task);
+ task->tk_status = 0;
}
/*
void rpc_delay(struct rpc_task *task, unsigned long delay)
{
task->tk_timeout = delay;
- rpc_sleep_on(&delay_queue, task, NULL, __rpc_atrun);
+ rpc_sleep_on(&delay_queue, task, __rpc_atrun);
}
EXPORT_SYMBOL_GPL(rpc_delay);
/*
* Helper to call task->tk_ops->rpc_call_prepare
*/
-static void rpc_prepare_task(struct rpc_task *task)
+void rpc_prepare_task(struct rpc_task *task)
{
- lock_kernel();
task->tk_ops->rpc_call_prepare(task, task->tk_calldata);
- unlock_kernel();
}
/*
{
task->tk_action = NULL;
if (task->tk_ops->rpc_call_done != NULL) {
- lock_kernel();
task->tk_ops->rpc_call_done(task, task->tk_calldata);
- unlock_kernel();
if (task->tk_action != NULL) {
WARN_ON(RPC_ASSASSINATED(task));
/* Always release the RPC slot and buffer memory */
void rpc_release_calldata(const struct rpc_call_ops *ops, void *calldata)
{
- if (ops->rpc_release != NULL) {
- lock_kernel();
+ if (ops->rpc_release != NULL)
ops->rpc_release(calldata);
- unlock_kernel();
- }
}
/*
*/
static void __rpc_execute(struct rpc_task *task)
{
- int status = 0;
+ struct rpc_wait_queue *queue;
+ int task_is_async = RPC_IS_ASYNC(task);
+ int status = 0;
dprintk("RPC: %5u __rpc_execute flags=0x%x\n",
task->tk_pid, task->tk_flags);
BUG_ON(RPC_IS_QUEUED(task));
for (;;) {
- /*
- * Garbage collection of pending timers...
- */
- rpc_delete_timer(task);
/*
* Execute any pending callback.
*/
- if (RPC_DO_CALLBACK(task)) {
- /* Define a callback save pointer */
+ if (task->tk_callback) {
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
+ * We set tk_callback to NULL before calling it,
+ * in case it sets the tk_callback field itself:
*/
- save_callback=task->tk_callback;
- task->tk_callback=NULL;
+ save_callback = task->tk_callback;
+ task->tk_callback = NULL;
save_callback(task);
}
*/
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;
- if (rpc_test_and_set_running(task))
- return;
+ /*
+ * The queue->lock protects against races with
+ * rpc_make_runnable().
+ *
+ * Note that once we clear RPC_TASK_RUNNING on an asynchronous
+ * rpc_task, rpc_make_runnable() can assign it to a
+ * different workqueue. We therefore cannot assume that the
+ * rpc_task pointer may still be dereferenced.
+ */
+ queue = task->tk_waitqueue;
+ spin_lock_bh(&queue->lock);
+ if (!RPC_IS_QUEUED(task)) {
+ spin_unlock_bh(&queue->lock);
continue;
}
+ rpc_clear_running(task);
+ spin_unlock_bh(&queue->lock);
+ if (task_is_async)
+ return;
/* sync task: sleep here */
dprintk("RPC: %5u sync task going to sleep\n", task->tk_pid);
__rpc_execute(container_of(work, struct rpc_task, u.tk_work));
}
-struct rpc_buffer {
- size_t len;
- char data[];
-};
-
/**
* rpc_malloc - allocate an RPC buffer
* @task: RPC task that will use this buffer
static void rpc_init_task(struct rpc_task *task, const struct rpc_task_setup *task_setup_data)
{
memset(task, 0, sizeof(*task));
- setup_timer(&task->tk_timer, (void (*)(unsigned long))rpc_run_timer,
- (unsigned long)task);
atomic_set(&task->tk_count, 1);
task->tk_flags = task_setup_data->flags;
task->tk_ops = task_setup_data->callback_ops;
task->tk_action = rpc_prepare_task;
if (task_setup_data->rpc_message != NULL) {
- memcpy(&task->tk_msg, task_setup_data->rpc_message, sizeof(task->tk_msg));
+ task->tk_msg.rpc_proc = task_setup_data->rpc_message->rpc_proc;
+ task->tk_msg.rpc_argp = task_setup_data->rpc_message->rpc_argp;
+ task->tk_msg.rpc_resp = task_setup_data->rpc_message->rpc_resp;
/* Bind the user cred */
- if (task->tk_msg.rpc_cred != NULL)
- rpcauth_holdcred(task);
- else
- rpcauth_bindcred(task);
+ rpcauth_bindcred(task, task_setup_data->rpc_message->rpc_cred, task_setup_data->flags);
if (task->tk_action == NULL)
rpc_call_start(task);
}
return (struct rpc_task *)mempool_alloc(rpc_task_mempool, GFP_NOFS);
}
-static void rpc_free_task_rcu(struct rcu_head *rcu)
-{
- struct rpc_task *task = container_of(rcu, struct rpc_task, u.tk_rcu);
- dprintk("RPC: %5u freeing task\n", task->tk_pid);
- mempool_free(task, rpc_task_mempool);
-}
-
/*
* Create a new task for the specified client.
*/
const struct rpc_call_ops *tk_ops = task->tk_ops;
void *calldata = task->tk_calldata;
- if (task->tk_flags & RPC_TASK_DYNAMIC)
- call_rcu_bh(&task->u.tk_rcu, rpc_free_task_rcu);
+ if (task->tk_flags & RPC_TASK_DYNAMIC) {
+ dprintk("RPC: %5u freeing task\n", task->tk_pid);
+ mempool_free(task, rpc_task_mempool);
+ }
rpc_release_calldata(tk_ops, calldata);
}
}
BUG_ON (RPC_IS_QUEUED(task));
- /* Synchronously delete any running timer */
- rpc_delete_timer(task);
-
#ifdef RPC_DEBUG
task->tk_magic = 0;
#endif
kmem_cache_destroy(rpc_task_slabp);
if (rpc_buffer_slabp)
kmem_cache_destroy(rpc_buffer_slabp);
+ rpc_destroy_wait_queue(&delay_queue);
}
int
rpc_init_mempool(void)
{
+ /*
+ * The following is not strictly a mempool initialisation,
+ * but there is no harm in doing it here
+ */
+ rpc_init_wait_queue(&delay_queue, "delayq");
+ if (!rpciod_start())
+ goto err_nomem;
+
rpc_task_slabp = kmem_cache_create("rpc_tasks",
sizeof(struct rpc_task),
0, SLAB_HWCACHE_ALIGN,
rpc_buffer_slabp);
if (!rpc_buffer_mempool)
goto err_nomem;
- if (!rpciod_start())
- goto err_nomem;
- /*
- * The following is not strictly a mempool initialisation,
- * but there is no harm in doing it here
- */
- rpc_init_wait_queue(&delay_queue, "delayq");
return 0;
err_nomem:
rpc_destroy_mempool();
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff