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Diffstat (limited to 'net/sunrpc/sched.c')
-rw-r--r--net/sunrpc/sched.c137
1 files changed, 85 insertions, 52 deletions
diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index 225e6510b523..79bc4cdf5d48 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -266,12 +266,28 @@ static int rpc_wait_bit_interruptible(void *word)
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);
}
@@ -295,13 +311,15 @@ EXPORT_SYMBOL(__rpc_wait_for_completion_task);
*/
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;
@@ -333,9 +351,6 @@ static void __rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
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);
@@ -346,6 +361,9 @@ static void __rpc_sleep_on(struct rpc_wait_queue *q, struct rpc_task *task,
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.
*/
@@ -409,16 +427,19 @@ __rpc_default_timer(struct rpc_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();
}
/*
@@ -481,14 +502,16 @@ 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);
+ 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;
}
@@ -504,7 +527,8 @@ void rpc_wake_up(struct rpc_wait_queue *queue)
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)
@@ -513,7 +537,8 @@ void rpc_wake_up(struct rpc_wait_queue *queue)
break;
head--;
}
- spin_unlock_bh(&queue->lock);
+ spin_unlock(&queue->lock);
+ rcu_read_unlock_bh();
}
/**
@@ -528,7 +553,8 @@ void rpc_wake_up_status(struct rpc_wait_queue *queue, int status)
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) {
@@ -539,7 +565,8 @@ void rpc_wake_up_status(struct rpc_wait_queue *queue, int status)
break;
head--;
}
- spin_unlock_bh(&queue->lock);
+ spin_unlock(&queue->lock);
+ rcu_read_unlock_bh();
}
static void __rpc_atrun(struct rpc_task *task)
@@ -561,7 +588,9 @@ void rpc_delay(struct rpc_task *task, unsigned long delay)
*/
static void rpc_prepare_task(struct rpc_task *task)
{
+ lock_kernel();
task->tk_ops->rpc_call_prepare(task, task->tk_calldata);
+ unlock_kernel();
}
/*
@@ -571,7 +600,9 @@ void rpc_exit_task(struct rpc_task *task)
{
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 */
@@ -581,6 +612,15 @@ void rpc_exit_task(struct rpc_task *task)
}
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).
*/
@@ -615,9 +655,7 @@ static int __rpc_execute(struct rpc_task *task)
*/
save_callback=task->tk_callback;
task->tk_callback=NULL;
- lock_kernel();
save_callback(task);
- unlock_kernel();
}
/*
@@ -628,9 +666,7 @@ static int __rpc_execute(struct rpc_task *task)
if (!RPC_IS_QUEUED(task)) {
if (task->tk_action == NULL)
break;
- lock_kernel();
task->tk_action(task);
- unlock_kernel();
}
/*
@@ -671,8 +707,6 @@ static int __rpc_execute(struct rpc_task *task)
}
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);
/* Release all resources associated with the task */
rpc_release_task(task);
return status;
@@ -786,15 +820,6 @@ void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt, int flags, cons
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 */
@@ -810,8 +835,9 @@ rpc_alloc_task(void)
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)
{
+ struct rpc_task *task = container_of(rcu, struct rpc_task, u.tk_rcu);
dprintk("RPC: %4d freeing task\n", task->tk_pid);
mempool_free(task, rpc_task_mempool);
}
@@ -847,16 +873,34 @@ cleanup:
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);
+
+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);
/* Remove from global task list */
@@ -869,23 +913,13 @@ void rpc_release_task(struct rpc_task *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
- 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);
}
/**
@@ -902,8 +936,7 @@ struct rpc_task *rpc_run_task(struct rpc_clnt *clnt, int flags,
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);