* Scheduling for synchronous and asynchronous RPC requests.
*
* Copyright (C) 1996 Olaf Kirch, <okir@monad.swb.de>
- *
+ *
* TCP NFS related read + write fixes
* (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
*/
static void __rpc_default_timer(struct rpc_task *task);
static void rpciod_killall(void);
static void rpc_async_schedule(struct work_struct *);
+static void rpc_release_task(struct rpc_task *task);
/*
* RPC tasks sit here while waiting for conditions to improve.
static inline void
__rpc_disable_timer(struct rpc_task *task)
{
- dprintk("RPC: %4d disabling timer\n", task->tk_pid);
+ dprintk("RPC: %5u disabling timer\n", task->tk_pid);
task->tk_timeout_fn = NULL;
task->tk_timeout = 0;
}
callback = task->tk_timeout_fn;
task->tk_timeout_fn = NULL;
if (callback && RPC_IS_QUEUED(task)) {
- dprintk("RPC: %4d running timer\n", task->tk_pid);
+ dprintk("RPC: %5u running timer\n", task->tk_pid);
callback(task);
}
smp_mb__before_clear_bit();
if (!task->tk_timeout)
return;
- dprintk("RPC: %4d setting alarm for %lu ms\n",
+ dprintk("RPC: %5u setting alarm for %lu ms\n",
task->tk_pid, task->tk_timeout * 1000 / HZ);
if (timer)
return;
if (test_and_clear_bit(RPC_TASK_HAS_TIMER, &task->tk_runstate)) {
del_singleshot_timer_sync(&task->tk_timer);
- dprintk("RPC: %4d deleting timer\n", task->tk_pid);
+ dprintk("RPC: %5u deleting timer\n", task->tk_pid);
}
}
queue->qlen++;
rpc_set_queued(task);
- dprintk("RPC: %4d added to queue %p \"%s\"\n",
- task->tk_pid, queue, rpc_qname(queue));
+ dprintk("RPC: %5u added to queue %p \"%s\"\n",
+ task->tk_pid, queue, rpc_qname(queue));
}
/*
else
list_del(&task->u.tk_wait.list);
queue->qlen--;
- dprintk("RPC: %4d removed from queue %p \"%s\"\n",
- task->tk_pid, queue, rpc_qname(queue));
+ dprintk("RPC: %5u removed from queue %p \"%s\"\n",
+ task->tk_pid, queue, rpc_qname(queue));
}
static inline void rpc_set_waitqueue_priority(struct rpc_wait_queue *queue, int priority)
return 0;
}
+static void rpc_set_active(struct rpc_task *task)
+{
+ if (test_and_set_bit(RPC_TASK_ACTIVE, &task->tk_runstate) != 0)
+ return;
+ spin_lock(&rpc_sched_lock);
+#ifdef RPC_DEBUG
+ task->tk_magic = RPC_TASK_MAGIC_ID;
+ task->tk_pid = rpc_task_id++;
+#endif
+ /* Add to global list of all tasks */
+ list_add_tail(&task->tk_task, &all_tasks);
+ spin_unlock(&rpc_sched_lock);
+}
+
/*
* Mark an RPC call as having completed by clearing the 'active' bit
*/
-static inline void rpc_mark_complete_task(struct rpc_task *task)
+static void rpc_mark_complete_task(struct rpc_task *task)
{
- rpc_clear_active(task);
+ smp_mb__before_clear_bit();
+ clear_bit(RPC_TASK_ACTIVE, &task->tk_runstate);
+ smp_mb__after_clear_bit();
wake_up_bit(&task->tk_runstate, RPC_TASK_ACTIVE);
}
/*
* Make an RPC task runnable.
*
- * Note: If the task is ASYNC, this must be called with
+ * Note: If the task is ASYNC, this must be called with
* the spinlock held to protect the wait queue operation.
*/
static void rpc_make_runnable(struct rpc_task *task)
{
- int do_ret;
-
BUG_ON(task->tk_timeout_fn);
- do_ret = rpc_test_and_set_running(task);
rpc_clear_queued(task);
- if (do_ret)
+ 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;
static void __rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
rpc_action action, rpc_action timer)
{
- dprintk("RPC: %4d sleep_on(queue \"%s\" time %ld)\n", task->tk_pid,
- rpc_qname(q), jiffies);
+ dprintk("RPC: %5u sleep_on(queue \"%s\" time %lu)\n",
+ task->tk_pid, rpc_qname(q), jiffies);
if (!RPC_IS_ASYNC(task) && !RPC_IS_ACTIVATED(task)) {
printk(KERN_ERR "RPC: Inactive synchronous task put to sleep!\n");
return;
}
- /* Mark the task as being activated if so needed */
- rpc_set_active(task);
-
__rpc_add_wait_queue(q, task);
BUG_ON(task->tk_callback != NULL);
void rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
rpc_action action, rpc_action timer)
{
+ /* Mark the task as being activated if so needed */
+ rpc_set_active(task);
+
/*
* Protect the queue operations.
*/
*/
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);
+ dprintk("RPC: %5u __rpc_wake_up_task (now %lu)\n",
+ task->tk_pid, jiffies);
#ifdef RPC_DEBUG
BUG_ON(task->tk_magic != RPC_TASK_MAGIC_ID);
rpc_make_runnable(task);
- dprintk("RPC: __rpc_wake_up_task done\n");
+ dprintk("RPC: __rpc_wake_up_task done\n");
}
/*
static void
__rpc_default_timer(struct rpc_task *task)
{
- dprintk("RPC: %d timeout (default timer)\n", task->tk_pid);
+ dprintk("RPC: %5u timeout (default timer)\n", task->tk_pid);
task->tk_status = -ETIMEDOUT;
rpc_wake_up_task(task);
}
*/
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;
- spin_lock_bh(&queue->lock);
+ /* Note: we're already in a bh-safe context */
+ spin_lock(&queue->lock);
__rpc_do_wake_up_task(task);
- spin_unlock_bh(&queue->lock);
+ spin_unlock(&queue->lock);
}
rpc_finish_wakeup(task);
}
+ rcu_read_unlock_bh();
}
/*
{
struct rpc_task *task = NULL;
- dprintk("RPC: wake_up_next(%p \"%s\")\n", queue, rpc_qname(queue));
- spin_lock_bh(&queue->lock);
+ dprintk("RPC: wake_up_next(%p \"%s\")\n",
+ queue, rpc_qname(queue));
+ rcu_read_lock_bh();
+ spin_lock(&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);
+ spin_unlock(&queue->lock);
+ rcu_read_unlock_bh();
return task;
}
struct rpc_task *task, *next;
struct list_head *head;
- spin_lock_bh(&queue->lock);
+ rcu_read_lock_bh();
+ spin_lock(&queue->lock);
head = &queue->tasks[queue->maxpriority];
for (;;) {
list_for_each_entry_safe(task, next, head, u.tk_wait.list)
break;
head--;
}
- spin_unlock_bh(&queue->lock);
+ spin_unlock(&queue->lock);
+ rcu_read_unlock_bh();
}
/**
struct rpc_task *task, *next;
struct list_head *head;
- spin_lock_bh(&queue->lock);
+ rcu_read_lock_bh();
+ spin_lock(&queue->lock);
head = &queue->tasks[queue->maxpriority];
for (;;) {
list_for_each_entry_safe(task, next, head, u.tk_wait.list) {
break;
head--;
}
- spin_unlock_bh(&queue->lock);
+ spin_unlock(&queue->lock);
+ rcu_read_unlock_bh();
}
static void __rpc_atrun(struct rpc_task *task)
*/
static 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 */
}
EXPORT_SYMBOL(rpc_exit_task);
+void rpc_release_calldata(const struct rpc_call_ops *ops, void *calldata)
+{
+ if (ops->rpc_release != NULL) {
+ lock_kernel();
+ ops->rpc_release(calldata);
+ unlock_kernel();
+ }
+}
+
/*
* This is the RPC `scheduler' (or rather, the finite state machine).
*/
-static int __rpc_execute(struct rpc_task *task)
+static void __rpc_execute(struct rpc_task *task)
{
int status = 0;
- dprintk("RPC: %4d rpc_execute flgs %x\n",
- task->tk_pid, task->tk_flags);
+ dprintk("RPC: %5u __rpc_execute flags=0x%x\n",
+ task->tk_pid, task->tk_flags);
BUG_ON(RPC_IS_QUEUED(task));
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
*/
save_callback=task->tk_callback;
task->tk_callback=NULL;
- lock_kernel();
save_callback(task);
- unlock_kernel();
}
/*
if (!RPC_IS_QUEUED(task)) {
if (task->tk_action == NULL)
break;
- lock_kernel();
task->tk_action(task);
- unlock_kernel();
}
/*
if (RPC_IS_ASYNC(task)) {
/* Careful! we may have raced... */
if (RPC_IS_QUEUED(task))
- return 0;
+ return;
if (rpc_test_and_set_running(task))
- return 0;
+ return;
continue;
}
/* sync task: sleep here */
- dprintk("RPC: %4d sync task going to sleep\n", task->tk_pid);
+ dprintk("RPC: %5u sync task going to sleep\n", task->tk_pid);
/* 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,
* clean up after sleeping on some queue, we don't
* break the loop here, but go around once more.
*/
- dprintk("RPC: %4d got signal\n", task->tk_pid);
+ dprintk("RPC: %5u got signal\n", task->tk_pid);
task->tk_flags |= RPC_TASK_KILLED;
rpc_exit(task, -ERESTARTSYS);
rpc_wake_up_task(task);
}
rpc_set_running(task);
- dprintk("RPC: %4d sync task resuming\n", task->tk_pid);
+ dprintk("RPC: %5u sync task resuming\n", task->tk_pid);
}
- dprintk("RPC: %4d, return %d, status %d\n", task->tk_pid, status, task->tk_status);
- /* Wake up anyone who is waiting for task completion */
- rpc_mark_complete_task(task);
+ dprintk("RPC: %5u return %d, status %d\n", task->tk_pid, status,
+ task->tk_status);
/* Release all resources associated with the task */
rpc_release_task(task);
- return status;
}
/*
* 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)
+void rpc_execute(struct rpc_task *task)
{
rpc_set_active(task);
rpc_set_running(task);
- return __rpc_execute(task);
+ __rpc_execute(task);
}
static void rpc_async_schedule(struct work_struct *work)
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);
-
BUG_ON(task->tk_ops == NULL);
/* starting timestamp */
task->tk_start = jiffies;
- dprintk("RPC: %4d new task procpid %d\n", task->tk_pid,
+ dprintk("RPC: new task initialized, procpid %u\n",
current->pid);
}
return (struct rpc_task *)mempool_alloc(rpc_task_mempool, GFP_NOFS);
}
-static void rpc_free_task(struct rpc_task *task)
+static void rpc_free_task(struct rcu_head *rcu)
{
- dprintk("RPC: %4d freeing task\n", task->tk_pid);
+ 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);
}
rpc_init_task(task, clnt, flags, tk_ops, calldata);
- dprintk("RPC: %4d allocated task\n", task->tk_pid);
+ dprintk("RPC: allocated task %p\n", task);
task->tk_flags |= RPC_TASK_DYNAMIC;
out:
return task;
goto out;
}
-void rpc_release_task(struct rpc_task *task)
+
+void rpc_put_task(struct rpc_task *task)
{
const struct rpc_call_ops *tk_ops = task->tk_ops;
void *calldata = task->tk_calldata;
+ if (!atomic_dec_and_test(&task->tk_count))
+ return;
+ /* 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;
+ }
+ if (task->tk_flags & RPC_TASK_DYNAMIC)
+ call_rcu_bh(&task->u.tk_rcu, rpc_free_task);
+ rpc_release_calldata(tk_ops, calldata);
+}
+EXPORT_SYMBOL(rpc_put_task);
+
+static void rpc_release_task(struct rpc_task *task)
+{
#ifdef RPC_DEBUG
BUG_ON(task->tk_magic != RPC_TASK_MAGIC_ID);
#endif
- if (!atomic_dec_and_test(&task->tk_count))
- return;
- dprintk("RPC: %4d release task\n", task->tk_pid);
+ dprintk("RPC: %5u release task\n", task->tk_pid);
/* Remove from global task list */
spin_lock(&rpc_sched_lock);
/* 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
- if (task->tk_flags & RPC_TASK_DYNAMIC)
- rpc_free_task(task);
- if (tk_ops->rpc_release)
- tk_ops->rpc_release(calldata);
+ /* Wake up anyone who is waiting for task completion */
+ rpc_mark_complete_task(task);
+
+ rpc_put_task(task);
}
/**
struct rpc_task *task;
task = rpc_new_task(clnt, flags, ops, data);
if (task == NULL) {
- if (ops->rpc_release != NULL)
- ops->rpc_release(data);
+ rpc_release_calldata(ops, data);
return ERR_PTR(-ENOMEM);
}
atomic_inc(&task->tk_count);
struct rpc_task *rovr;
struct list_head *le;
- dprintk("RPC: killing all tasks for client %p\n", clnt);
+ dprintk("RPC: killing all tasks for client %p\n", clnt);
/*
* Spin lock all_tasks to prevent changes...
rpc_killall_tasks(NULL);
flush_workqueue(rpciod_workqueue);
if (!list_empty(&all_tasks)) {
- dprintk("rpciod_killall: waiting for tasks to exit\n");
+ dprintk("RPC: rpciod_killall: waiting for tasks "
+ "to exit\n");
yield();
}
}
int error = 0;
mutex_lock(&rpciod_mutex);
- dprintk("rpciod_up: users %d\n", rpciod_users);
+ dprintk("RPC: rpciod_up: users %u\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);
+ printk(KERN_WARNING "rpciod_up: no workqueue, %u users??\n", rpciod_users);
/*
* Create the rpciod thread and wait for it to start.
*/
rpciod_down(void)
{
mutex_lock(&rpciod_mutex);
- dprintk("rpciod_down sema %d\n", rpciod_users);
+ dprintk("RPC: rpciod_down sema %u\n", rpciod_users);
if (rpciod_users) {
if (--rpciod_users)
goto out;
printk(KERN_WARNING "rpciod_down: no users??\n");
if (!rpciod_workqueue) {
- dprintk("rpciod_down: Nothing to do!\n");
+ dprintk("RPC: rpciod_down: Nothing to do!\n");
goto out;
}
rpciod_killall();
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",
+ printk("%5u %04d %04x %6d %8p %6d %8p %8ld %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,