* - Next, the caller puts together the RPC message, stuffs it into
* the request struct, and calls xprt_transmit().
* - xprt_transmit sends the message and installs the caller on the
- * transport's wait list. At the same time, it installs a timer that
- * is run after the packet's timeout has expired.
+ * transport's wait list. At the same time, if a reply is expected,
+ * it installs a timer that is run after the packet's timeout has
+ * expired.
* - When a packet arrives, the data_ready handler walks the list of
* pending requests for that transport. If a matching XID is found, the
* caller is woken up, and the timer removed.
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
-#include <linux/random.h>
+#include <linux/net.h>
+#include <linux/ktime.h>
#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/metrics.h>
+#include <linux/sunrpc/bc_xprt.h>
+
+#include "sunrpc.h"
/*
* Local variables
*/
#ifdef RPC_DEBUG
-# undef RPC_DEBUG_DATA
# define RPCDBG_FACILITY RPCDBG_XPRT
#endif
* Local functions
*/
static void xprt_request_init(struct rpc_task *, struct rpc_xprt *);
-static inline void do_xprt_reserve(struct rpc_task *);
static void xprt_connect_status(struct rpc_task *task);
static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *);
-static int xprt_clear_backlog(struct rpc_xprt *xprt);
+static DEFINE_SPINLOCK(xprt_list_lock);
+static LIST_HEAD(xprt_list);
/*
- * Serialize write access to transports, in order to prevent different
- * requests from interfering with each other.
- * Also prevents transport connects from colliding with writes.
+ * The transport code maintains an estimate on the maximum number of out-
+ * standing RPC requests, using a smoothed version of the congestion
+ * avoidance implemented in 44BSD. This is basically the Van Jacobson
+ * congestion algorithm: If a retransmit occurs, the congestion window is
+ * halved; otherwise, it is incremented by 1/cwnd when
+ *
+ * - a reply is received and
+ * - a full number of requests are outstanding and
+ * - the congestion window hasn't been updated recently.
*/
-static int
-__xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task)
+#define RPC_CWNDSHIFT (8U)
+#define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT)
+#define RPC_INITCWND RPC_CWNDSCALE
+#define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT)
+
+#define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd)
+
+/**
+ * xprt_register_transport - register a transport implementation
+ * @transport: transport to register
+ *
+ * If a transport implementation is loaded as a kernel module, it can
+ * call this interface to make itself known to the RPC client.
+ *
+ * Returns:
+ * 0: transport successfully registered
+ * -EEXIST: transport already registered
+ * -EINVAL: transport module being unloaded
+ */
+int xprt_register_transport(struct xprt_class *transport)
{
+ struct xprt_class *t;
+ int result;
+
+ result = -EEXIST;
+ spin_lock(&xprt_list_lock);
+ list_for_each_entry(t, &xprt_list, list) {
+ /* don't register the same transport class twice */
+ if (t->ident == transport->ident)
+ goto out;
+ }
+
+ list_add_tail(&transport->list, &xprt_list);
+ printk(KERN_INFO "RPC: Registered %s transport module.\n",
+ transport->name);
+ result = 0;
+
+out:
+ spin_unlock(&xprt_list_lock);
+ return result;
+}
+EXPORT_SYMBOL_GPL(xprt_register_transport);
+
+/**
+ * xprt_unregister_transport - unregister a transport implementation
+ * @transport: transport to unregister
+ *
+ * Returns:
+ * 0: transport successfully unregistered
+ * -ENOENT: transport never registered
+ */
+int xprt_unregister_transport(struct xprt_class *transport)
+{
+ struct xprt_class *t;
+ int result;
+
+ result = 0;
+ spin_lock(&xprt_list_lock);
+ list_for_each_entry(t, &xprt_list, list) {
+ if (t == transport) {
+ printk(KERN_INFO
+ "RPC: Unregistered %s transport module.\n",
+ transport->name);
+ list_del_init(&transport->list);
+ goto out;
+ }
+ }
+ result = -ENOENT;
+
+out:
+ spin_unlock(&xprt_list_lock);
+ return result;
+}
+EXPORT_SYMBOL_GPL(xprt_unregister_transport);
+
+/**
+ * xprt_load_transport - load a transport implementation
+ * @transport_name: transport to load
+ *
+ * Returns:
+ * 0: transport successfully loaded
+ * -ENOENT: transport module not available
+ */
+int xprt_load_transport(const char *transport_name)
+{
+ struct xprt_class *t;
+ char module_name[sizeof t->name + 5];
+ int result;
+
+ result = 0;
+ spin_lock(&xprt_list_lock);
+ list_for_each_entry(t, &xprt_list, list) {
+ if (strcmp(t->name, transport_name) == 0) {
+ spin_unlock(&xprt_list_lock);
+ goto out;
+ }
+ }
+ spin_unlock(&xprt_list_lock);
+ strcpy(module_name, "xprt");
+ strncat(module_name, transport_name, sizeof t->name);
+ result = request_module(module_name);
+out:
+ return result;
+}
+EXPORT_SYMBOL_GPL(xprt_load_transport);
+
+/**
+ * xprt_reserve_xprt - serialize write access to transports
+ * @task: task that is requesting access to the transport
+ *
+ * This prevents mixing the payload of separate requests, and prevents
+ * transport connects from colliding with writes. No congestion control
+ * is provided.
+ */
+int xprt_reserve_xprt(struct rpc_task *task)
+{
+ struct rpc_rqst *req = task->tk_rqstp;
+ struct rpc_xprt *xprt = req->rq_xprt;
+
+ if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) {
+ if (task == xprt->snd_task)
+ return 1;
+ if (task == NULL)
+ return 0;
+ goto out_sleep;
+ }
+ xprt->snd_task = task;
+ if (req) {
+ req->rq_bytes_sent = 0;
+ req->rq_ntrans++;
+ }
+ return 1;
+
+out_sleep:
+ dprintk("RPC: %5u failed to lock transport %p\n",
+ task->tk_pid, xprt);
+ task->tk_timeout = 0;
+ task->tk_status = -EAGAIN;
+ if (req && req->rq_ntrans)
+ rpc_sleep_on(&xprt->resend, task, NULL);
+ else
+ rpc_sleep_on(&xprt->sending, task, NULL);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xprt_reserve_xprt);
+
+static void xprt_clear_locked(struct rpc_xprt *xprt)
+{
+ xprt->snd_task = NULL;
+ if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state) || xprt->shutdown) {
+ smp_mb__before_clear_bit();
+ clear_bit(XPRT_LOCKED, &xprt->state);
+ smp_mb__after_clear_bit();
+ } else
+ queue_work(rpciod_workqueue, &xprt->task_cleanup);
+}
+
+/*
+ * xprt_reserve_xprt_cong - serialize write access to transports
+ * @task: task that is requesting access to the transport
+ *
+ * Same as xprt_reserve_xprt, but Van Jacobson congestion control is
+ * integrated into the decision of whether a request is allowed to be
+ * woken up and given access to the transport.
+ */
+int xprt_reserve_xprt_cong(struct rpc_task *task)
+{
+ struct rpc_xprt *xprt = task->tk_xprt;
struct rpc_rqst *req = task->tk_rqstp;
if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) {
return 1;
goto out_sleep;
}
- if (xprt->nocong || __xprt_get_cong(xprt, task)) {
+ if (__xprt_get_cong(xprt, task)) {
xprt->snd_task = task;
if (req) {
req->rq_bytes_sent = 0;
}
return 1;
}
- smp_mb__before_clear_bit();
- clear_bit(XPRT_LOCKED, &xprt->state);
- smp_mb__after_clear_bit();
+ xprt_clear_locked(xprt);
out_sleep:
- dprintk("RPC: %4d failed to lock transport %p\n", task->tk_pid, xprt);
+ dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt);
task->tk_timeout = 0;
task->tk_status = -EAGAIN;
if (req && req->rq_ntrans)
- rpc_sleep_on(&xprt->resend, task, NULL, NULL);
+ rpc_sleep_on(&xprt->resend, task, NULL);
else
- rpc_sleep_on(&xprt->sending, task, NULL, NULL);
+ rpc_sleep_on(&xprt->sending, task, NULL);
return 0;
}
+EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong);
-static inline int
-xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task)
+static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task)
{
int retval;
spin_lock_bh(&xprt->transport_lock);
- retval = __xprt_lock_write(xprt, task);
+ retval = xprt->ops->reserve_xprt(task);
spin_unlock_bh(&xprt->transport_lock);
return retval;
}
+static void __xprt_lock_write_next(struct rpc_xprt *xprt)
+{
+ struct rpc_task *task;
+ struct rpc_rqst *req;
+
+ if (test_and_set_bit(XPRT_LOCKED, &xprt->state))
+ return;
-static void
-__xprt_lock_write_next(struct rpc_xprt *xprt)
+ task = rpc_wake_up_next(&xprt->resend);
+ if (!task) {
+ task = rpc_wake_up_next(&xprt->sending);
+ if (!task)
+ goto out_unlock;
+ }
+
+ req = task->tk_rqstp;
+ xprt->snd_task = task;
+ if (req) {
+ req->rq_bytes_sent = 0;
+ req->rq_ntrans++;
+ }
+ return;
+
+out_unlock:
+ xprt_clear_locked(xprt);
+}
+
+static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt)
{
struct rpc_task *task;
if (test_and_set_bit(XPRT_LOCKED, &xprt->state))
return;
- if (!xprt->nocong && RPCXPRT_CONGESTED(xprt))
+ if (RPCXPRT_CONGESTED(xprt))
goto out_unlock;
task = rpc_wake_up_next(&xprt->resend);
if (!task) {
if (!task)
goto out_unlock;
}
- if (xprt->nocong || __xprt_get_cong(xprt, task)) {
+ if (__xprt_get_cong(xprt, task)) {
struct rpc_rqst *req = task->tk_rqstp;
xprt->snd_task = task;
if (req) {
return;
}
out_unlock:
- smp_mb__before_clear_bit();
- clear_bit(XPRT_LOCKED, &xprt->state);
- smp_mb__after_clear_bit();
+ xprt_clear_locked(xprt);
}
-/*
- * Releases the transport for use by other requests.
+/**
+ * xprt_release_xprt - allow other requests to use a transport
+ * @xprt: transport with other tasks potentially waiting
+ * @task: task that is releasing access to the transport
+ *
+ * Note that "task" can be NULL. No congestion control is provided.
*/
-static void
-__xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)
+void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
{
if (xprt->snd_task == task) {
- xprt->snd_task = NULL;
- smp_mb__before_clear_bit();
- clear_bit(XPRT_LOCKED, &xprt->state);
- smp_mb__after_clear_bit();
+ xprt_clear_locked(xprt);
__xprt_lock_write_next(xprt);
}
}
+EXPORT_SYMBOL_GPL(xprt_release_xprt);
-static inline void
-xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)
+/**
+ * xprt_release_xprt_cong - allow other requests to use a transport
+ * @xprt: transport with other tasks potentially waiting
+ * @task: task that is releasing access to the transport
+ *
+ * Note that "task" can be NULL. Another task is awoken to use the
+ * transport if the transport's congestion window allows it.
+ */
+void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task)
+{
+ if (xprt->snd_task == task) {
+ xprt_clear_locked(xprt);
+ __xprt_lock_write_next_cong(xprt);
+ }
+}
+EXPORT_SYMBOL_GPL(xprt_release_xprt_cong);
+
+static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)
{
spin_lock_bh(&xprt->transport_lock);
- __xprt_release_write(xprt, task);
+ xprt->ops->release_xprt(xprt, task);
spin_unlock_bh(&xprt->transport_lock);
}
if (req->rq_cong)
return 1;
- dprintk("RPC: %4d xprt_cwnd_limited cong = %ld cwnd = %ld\n",
+ dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n",
task->tk_pid, xprt->cong, xprt->cwnd);
if (RPCXPRT_CONGESTED(xprt))
return 0;
return;
req->rq_cong = 0;
xprt->cong -= RPC_CWNDSCALE;
- __xprt_lock_write_next(xprt);
+ __xprt_lock_write_next_cong(xprt);
}
-/*
- * Adjust RPC congestion window
+/**
+ * xprt_release_rqst_cong - housekeeping when request is complete
+ * @task: RPC request that recently completed
+ *
+ * Useful for transports that require congestion control.
+ */
+void xprt_release_rqst_cong(struct rpc_task *task)
+{
+ __xprt_put_cong(task->tk_xprt, task->tk_rqstp);
+}
+EXPORT_SYMBOL_GPL(xprt_release_rqst_cong);
+
+/**
+ * xprt_adjust_cwnd - adjust transport congestion window
+ * @task: recently completed RPC request used to adjust window
+ * @result: result code of completed RPC request
+ *
* We use a time-smoothed congestion estimator to avoid heavy oscillation.
*/
-static void
-xprt_adjust_cwnd(struct rpc_xprt *xprt, int result)
+void xprt_adjust_cwnd(struct rpc_task *task, int result)
{
- unsigned long cwnd;
+ struct rpc_rqst *req = task->tk_rqstp;
+ struct rpc_xprt *xprt = task->tk_xprt;
+ unsigned long cwnd = xprt->cwnd;
- cwnd = xprt->cwnd;
if (result >= 0 && cwnd <= xprt->cong) {
/* The (cwnd >> 1) term makes sure
* the result gets rounded properly. */
cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd;
if (cwnd > RPC_MAXCWND(xprt))
cwnd = RPC_MAXCWND(xprt);
- __xprt_lock_write_next(xprt);
+ __xprt_lock_write_next_cong(xprt);
} else if (result == -ETIMEDOUT) {
cwnd >>= 1;
if (cwnd < RPC_CWNDSCALE)
cwnd = RPC_CWNDSCALE;
}
- dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n",
+ dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n",
xprt->cong, xprt->cwnd, cwnd);
xprt->cwnd = cwnd;
+ __xprt_put_cong(xprt, req);
}
+EXPORT_SYMBOL_GPL(xprt_adjust_cwnd);
/**
* xprt_wake_pending_tasks - wake all tasks on a transport's pending queue
else
rpc_wake_up(&xprt->pending);
}
+EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks);
+
+/**
+ * xprt_wait_for_buffer_space - wait for transport output buffer to clear
+ * @task: task to be put to sleep
+ * @action: function pointer to be executed after wait
+ */
+void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action)
+{
+ struct rpc_rqst *req = task->tk_rqstp;
+ struct rpc_xprt *xprt = req->rq_xprt;
+
+ task->tk_timeout = req->rq_timeout;
+ rpc_sleep_on(&xprt->pending, task, action);
+}
+EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space);
+
+/**
+ * xprt_write_space - wake the task waiting for transport output buffer space
+ * @xprt: transport with waiting tasks
+ *
+ * Can be called in a soft IRQ context, so xprt_write_space never sleeps.
+ */
+void xprt_write_space(struct rpc_xprt *xprt)
+{
+ if (unlikely(xprt->shutdown))
+ return;
+
+ spin_lock_bh(&xprt->transport_lock);
+ if (xprt->snd_task) {
+ dprintk("RPC: write space: waking waiting task on "
+ "xprt %p\n", xprt);
+ rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task);
+ }
+ spin_unlock_bh(&xprt->transport_lock);
+}
+EXPORT_SYMBOL_GPL(xprt_write_space);
+
+/**
+ * xprt_set_retrans_timeout_def - set a request's retransmit timeout
+ * @task: task whose timeout is to be set
+ *
+ * Set a request's retransmit timeout based on the transport's
+ * default timeout parameters. Used by transports that don't adjust
+ * the retransmit timeout based on round-trip time estimation.
+ */
+void xprt_set_retrans_timeout_def(struct rpc_task *task)
+{
+ task->tk_timeout = task->tk_rqstp->rq_timeout;
+}
+EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def);
+
+/*
+ * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout
+ * @task: task whose timeout is to be set
+ *
+ * Set a request's retransmit timeout using the RTT estimator.
+ */
+void xprt_set_retrans_timeout_rtt(struct rpc_task *task)
+{
+ int timer = task->tk_msg.rpc_proc->p_timer;
+ struct rpc_clnt *clnt = task->tk_client;
+ struct rpc_rtt *rtt = clnt->cl_rtt;
+ struct rpc_rqst *req = task->tk_rqstp;
+ unsigned long max_timeout = clnt->cl_timeout->to_maxval;
+
+ task->tk_timeout = rpc_calc_rto(rtt, timer);
+ task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries;
+ if (task->tk_timeout > max_timeout || task->tk_timeout == 0)
+ task->tk_timeout = max_timeout;
+}
+EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt);
static void xprt_reset_majortimeo(struct rpc_rqst *req)
{
- struct rpc_timeout *to = &req->rq_xprt->timeout;
+ const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout;
req->rq_majortimeo = req->rq_timeout;
if (to->to_exponential)
int xprt_adjust_timeout(struct rpc_rqst *req)
{
struct rpc_xprt *xprt = req->rq_xprt;
- struct rpc_timeout *to = &xprt->timeout;
+ const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout;
int status = 0;
if (time_before(jiffies, req->rq_majortimeo)) {
if (to->to_maxval && req->rq_timeout >= to->to_maxval)
req->rq_timeout = to->to_maxval;
req->rq_retries++;
- pprintk("RPC: %lu retrans\n", jiffies);
} else {
req->rq_timeout = to->to_initval;
req->rq_retries = 0;
spin_lock_bh(&xprt->transport_lock);
rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval);
spin_unlock_bh(&xprt->transport_lock);
- pprintk("RPC: %lu timeout\n", jiffies);
status = -ETIMEDOUT;
}
return status;
}
-static void xprt_autoclose(void *args)
+static void xprt_autoclose(struct work_struct *work)
{
- struct rpc_xprt *xprt = (struct rpc_xprt *)args;
+ struct rpc_xprt *xprt =
+ container_of(work, struct rpc_xprt, task_cleanup);
- xprt_disconnect(xprt);
xprt->ops->close(xprt);
+ clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
xprt_release_write(xprt, NULL);
}
/**
- * xprt_disconnect - mark a transport as disconnected
+ * xprt_disconnect_done - mark a transport as disconnected
* @xprt: transport to flag for disconnect
*
*/
-void xprt_disconnect(struct rpc_xprt *xprt)
+void xprt_disconnect_done(struct rpc_xprt *xprt)
{
- dprintk("RPC: disconnected transport %p\n", xprt);
+ dprintk("RPC: disconnected transport %p\n", xprt);
spin_lock_bh(&xprt->transport_lock);
xprt_clear_connected(xprt);
- xprt_wake_pending_tasks(xprt, -ENOTCONN);
+ xprt_wake_pending_tasks(xprt, -EAGAIN);
+ spin_unlock_bh(&xprt->transport_lock);
+}
+EXPORT_SYMBOL_GPL(xprt_disconnect_done);
+
+/**
+ * xprt_force_disconnect - force a transport to disconnect
+ * @xprt: transport to disconnect
+ *
+ */
+void xprt_force_disconnect(struct rpc_xprt *xprt)
+{
+ /* Don't race with the test_bit() in xprt_clear_locked() */
+ spin_lock_bh(&xprt->transport_lock);
+ set_bit(XPRT_CLOSE_WAIT, &xprt->state);
+ /* Try to schedule an autoclose RPC call */
+ if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0)
+ queue_work(rpciod_workqueue, &xprt->task_cleanup);
+ xprt_wake_pending_tasks(xprt, -EAGAIN);
+ spin_unlock_bh(&xprt->transport_lock);
+}
+
+/**
+ * xprt_conditional_disconnect - force a transport to disconnect
+ * @xprt: transport to disconnect
+ * @cookie: 'connection cookie'
+ *
+ * This attempts to break the connection if and only if 'cookie' matches
+ * the current transport 'connection cookie'. It ensures that we don't
+ * try to break the connection more than once when we need to retransmit
+ * a batch of RPC requests.
+ *
+ */
+void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie)
+{
+ /* Don't race with the test_bit() in xprt_clear_locked() */
+ spin_lock_bh(&xprt->transport_lock);
+ if (cookie != xprt->connect_cookie)
+ goto out;
+ if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt))
+ goto out;
+ set_bit(XPRT_CLOSE_WAIT, &xprt->state);
+ /* Try to schedule an autoclose RPC call */
+ if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0)
+ queue_work(rpciod_workqueue, &xprt->task_cleanup);
+ xprt_wake_pending_tasks(xprt, -EAGAIN);
+out:
spin_unlock_bh(&xprt->transport_lock);
}
if (test_and_set_bit(XPRT_LOCKED, &xprt->state))
goto out_abort;
spin_unlock(&xprt->transport_lock);
- if (xprt_connecting(xprt))
- xprt_release_write(xprt, NULL);
- else
- schedule_work(&xprt->task_cleanup);
+ set_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
+ queue_work(rpciod_workqueue, &xprt->task_cleanup);
return;
out_abort:
spin_unlock(&xprt->transport_lock);
{
struct rpc_xprt *xprt = task->tk_xprt;
- dprintk("RPC: %4d xprt_connect xprt %p %s connected\n", task->tk_pid,
+ dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid,
xprt, (xprt_connected(xprt) ? "is" : "is not"));
- if (xprt->shutdown) {
- task->tk_status = -EIO;
- return;
- }
- if (!xprt->addr.sin_port) {
- task->tk_status = -EIO;
+ if (!xprt_bound(xprt)) {
+ task->tk_status = -EAGAIN;
return;
}
if (!xprt_lock_write(xprt, task))
return;
+
+ if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state))
+ xprt->ops->close(xprt);
+
if (xprt_connected(xprt))
xprt_release_write(xprt, task);
else {
if (task->tk_rqstp)
task->tk_rqstp->rq_bytes_sent = 0;
- task->tk_timeout = RPC_CONNECT_TIMEOUT;
- rpc_sleep_on(&xprt->pending, task, xprt_connect_status, NULL);
+ task->tk_timeout = task->tk_rqstp->rq_timeout;
+ rpc_sleep_on(&xprt->pending, task, xprt_connect_status);
+
+ if (test_bit(XPRT_CLOSING, &xprt->state))
+ return;
+ if (xprt_test_and_set_connecting(xprt))
+ return;
+ xprt->stat.connect_start = jiffies;
xprt->ops->connect(task);
}
- return;
}
static void xprt_connect_status(struct rpc_task *task)
{
struct rpc_xprt *xprt = task->tk_xprt;
- if (task->tk_status >= 0) {
- dprintk("RPC: %4d xprt_connect_status: connection established\n",
+ if (task->tk_status == 0) {
+ xprt->stat.connect_count++;
+ xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start;
+ dprintk("RPC: %5u xprt_connect_status: connection established\n",
task->tk_pid);
return;
}
switch (task->tk_status) {
- case -ECONNREFUSED:
- case -ECONNRESET:
- dprintk("RPC: %4d xprt_connect_status: server %s refused connection\n",
- task->tk_pid, task->tk_client->cl_server);
- break;
- case -ENOTCONN:
- dprintk("RPC: %4d xprt_connect_status: connection broken\n",
- task->tk_pid);
+ case -EAGAIN:
+ dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid);
break;
case -ETIMEDOUT:
- dprintk("RPC: %4d xprt_connect_status: connect attempt timed out\n",
- task->tk_pid);
+ dprintk("RPC: %5u xprt_connect_status: connect attempt timed "
+ "out\n", task->tk_pid);
break;
default:
- dprintk("RPC: %4d xprt_connect_status: error %d connecting to server %s\n",
- task->tk_pid, -task->tk_status, task->tk_client->cl_server);
- xprt_release_write(xprt, task);
- task->tk_status = -EIO;
- return;
- }
-
- /* if soft mounted, just cause this RPC to fail */
- if (RPC_IS_SOFT(task)) {
+ dprintk("RPC: %5u xprt_connect_status: error %d connecting to "
+ "server %s\n", task->tk_pid, -task->tk_status,
+ task->tk_client->cl_server);
xprt_release_write(xprt, task);
task->tk_status = -EIO;
}
* @xid: RPC XID of incoming reply
*
*/
-struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid)
+struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid)
{
struct list_head *pos;
- struct rpc_rqst *req = NULL;
list_for_each(pos, &xprt->recv) {
struct rpc_rqst *entry = list_entry(pos, struct rpc_rqst, rq_list);
- if (entry->rq_xid == xid) {
- req = entry;
- break;
- }
+ if (entry->rq_xid == xid)
+ return entry;
+ }
+
+ dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n",
+ ntohl(xid));
+ xprt->stat.bad_xids++;
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(xprt_lookup_rqst);
+
+static void xprt_update_rtt(struct rpc_task *task)
+{
+ struct rpc_rqst *req = task->tk_rqstp;
+ struct rpc_rtt *rtt = task->tk_client->cl_rtt;
+ unsigned timer = task->tk_msg.rpc_proc->p_timer;
+ long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt));
+
+ if (timer) {
+ if (req->rq_ntrans == 1)
+ rpc_update_rtt(rtt, timer, m);
+ rpc_set_timeo(rtt, timer, req->rq_ntrans - 1);
}
- return req;
}
/**
* xprt_complete_rqst - called when reply processing is complete
- * @xprt: controlling transport
- * @req: RPC request that just completed
+ * @task: RPC request that recently completed
* @copied: actual number of bytes received from the transport
*
+ * Caller holds transport lock.
*/
-void xprt_complete_rqst(struct rpc_xprt *xprt, struct rpc_rqst *req, int copied)
+void xprt_complete_rqst(struct rpc_task *task, int copied)
{
- struct rpc_task *task = req->rq_task;
- struct rpc_clnt *clnt = task->tk_client;
+ struct rpc_rqst *req = task->tk_rqstp;
+ struct rpc_xprt *xprt = req->rq_xprt;
- /* Adjust congestion window */
- if (!xprt->nocong) {
- unsigned timer = task->tk_msg.rpc_proc->p_timer;
- xprt_adjust_cwnd(xprt, copied);
- __xprt_put_cong(xprt, req);
- if (timer) {
- if (req->rq_ntrans == 1)
- rpc_update_rtt(clnt->cl_rtt, timer,
- (long)jiffies - req->rq_xtime);
- rpc_set_timeo(clnt->cl_rtt, timer, req->rq_ntrans - 1);
- }
- }
+ dprintk("RPC: %5u xid %08x complete (%d bytes received)\n",
+ task->tk_pid, ntohl(req->rq_xid), copied);
-#ifdef RPC_PROFILE
- /* Profile only reads for now */
- if (copied > 1024) {
- static unsigned long nextstat;
- static unsigned long pkt_rtt, pkt_len, pkt_cnt;
-
- pkt_cnt++;
- pkt_len += req->rq_slen + copied;
- pkt_rtt += jiffies - req->rq_xtime;
- if (time_before(nextstat, jiffies)) {
- printk("RPC: %lu %ld cwnd\n", jiffies, xprt->cwnd);
- printk("RPC: %ld %ld %ld %ld stat\n",
- jiffies, pkt_cnt, pkt_len, pkt_rtt);
- pkt_rtt = pkt_len = pkt_cnt = 0;
- nextstat = jiffies + 5 * HZ;
- }
- }
-#endif
+ xprt->stat.recvs++;
+ req->rq_rtt = ktime_sub(ktime_get(), req->rq_xtime);
+ if (xprt->ops->timer != NULL)
+ xprt_update_rtt(task);
- dprintk("RPC: %4d has input (%d bytes)\n", task->tk_pid, copied);
list_del_init(&req->rq_list);
- req->rq_received = req->rq_private_buf.len = copied;
-
- /* ... and wake up the process. */
- rpc_wake_up_task(task);
- return;
+ req->rq_private_buf.len = copied;
+ /* Ensure all writes are done before we update */
+ /* req->rq_reply_bytes_recvd */
+ smp_wmb();
+ req->rq_reply_bytes_recvd = copied;
+ rpc_wake_up_queued_task(&xprt->pending, task);
}
+EXPORT_SYMBOL_GPL(xprt_complete_rqst);
-/*
- * RPC receive timeout handler.
- */
-static void
-xprt_timer(struct rpc_task *task)
+static void xprt_timer(struct rpc_task *task)
{
- struct rpc_rqst *req = task->tk_rqstp;
+ struct rpc_rqst *req = task->tk_rqstp;
struct rpc_xprt *xprt = req->rq_xprt;
- spin_lock(&xprt->transport_lock);
- if (req->rq_received)
- goto out;
-
- xprt_adjust_cwnd(req->rq_xprt, -ETIMEDOUT);
- __xprt_put_cong(xprt, req);
+ if (task->tk_status != -ETIMEDOUT)
+ return;
+ dprintk("RPC: %5u xprt_timer\n", task->tk_pid);
- dprintk("RPC: %4d xprt_timer (%s request)\n",
- task->tk_pid, req ? "pending" : "backlogged");
+ spin_lock_bh(&xprt->transport_lock);
+ if (!req->rq_reply_bytes_recvd) {
+ if (xprt->ops->timer)
+ xprt->ops->timer(task);
+ } else
+ task->tk_status = 0;
+ spin_unlock_bh(&xprt->transport_lock);
+}
- task->tk_status = -ETIMEDOUT;
-out:
- task->tk_timeout = 0;
- rpc_wake_up_task(task);
- spin_unlock(&xprt->transport_lock);
+static inline int xprt_has_timer(struct rpc_xprt *xprt)
+{
+ return xprt->idle_timeout != 0;
}
/**
struct rpc_xprt *xprt = req->rq_xprt;
int err = 0;
- dprintk("RPC: %4d xprt_prepare_transmit\n", task->tk_pid);
-
- if (xprt->shutdown)
- return -EIO;
+ dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid);
spin_lock_bh(&xprt->transport_lock);
- if (req->rq_received && !req->rq_bytes_sent) {
- err = req->rq_received;
+ if (req->rq_reply_bytes_recvd && !req->rq_bytes_sent) {
+ err = req->rq_reply_bytes_recvd;
goto out_unlock;
}
- if (!__xprt_lock_write(xprt, task)) {
+ if (!xprt->ops->reserve_xprt(task))
err = -EAGAIN;
- goto out_unlock;
- }
-
- if (!xprt_connected(xprt)) {
- err = -ENOTCONN;
- goto out_unlock;
- }
out_unlock:
spin_unlock_bh(&xprt->transport_lock);
return err;
}
+void xprt_end_transmit(struct rpc_task *task)
+{
+ xprt_release_write(task->tk_rqstp->rq_xprt, task);
+}
+
/**
* xprt_transmit - send an RPC request on a transport
* @task: controlling RPC task
*/
void xprt_transmit(struct rpc_task *task)
{
- struct rpc_clnt *clnt = task->tk_client;
struct rpc_rqst *req = task->tk_rqstp;
struct rpc_xprt *xprt = req->rq_xprt;
int status;
- dprintk("RPC: %4d xprt_transmit(%u)\n", task->tk_pid, req->rq_slen);
+ dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen);
- smp_rmb();
- if (!req->rq_received) {
- if (list_empty(&req->rq_list)) {
+ if (!req->rq_reply_bytes_recvd) {
+ if (list_empty(&req->rq_list) && rpc_reply_expected(task)) {
+ /*
+ * Add to the list only if we're expecting a reply
+ */
spin_lock_bh(&xprt->transport_lock);
/* Update the softirq receive buffer */
memcpy(&req->rq_private_buf, &req->rq_rcv_buf,
} else if (!req->rq_bytes_sent)
return;
+ req->rq_connect_cookie = xprt->connect_cookie;
+ req->rq_xtime = ktime_get();
status = xprt->ops->send_request(task);
- if (!status)
- goto out_receive;
-
- /* Note: at this point, task->tk_sleeping has not yet been set,
- * hence there is no danger of the waking up task being put on
- * schedq, and being picked up by a parallel run of rpciod().
- */
- task->tk_status = status;
-
- switch (status) {
- case -ECONNREFUSED:
- task->tk_timeout = RPC_REESTABLISH_TIMEOUT;
- rpc_sleep_on(&xprt->sending, task, NULL, NULL);
- case -EAGAIN:
- case -ENOTCONN:
+ if (status != 0) {
+ task->tk_status = status;
return;
- default:
- if (xprt->stream)
- xprt_disconnect(xprt);
}
- xprt_release_write(xprt, task);
- return;
- out_receive:
- dprintk("RPC: %4d xmit complete\n", task->tk_pid);
- /* Set the task's receive timeout value */
+
+ dprintk("RPC: %5u xmit complete\n", task->tk_pid);
spin_lock_bh(&xprt->transport_lock);
- if (!xprt->nocong) {
- int timer = task->tk_msg.rpc_proc->p_timer;
- task->tk_timeout = rpc_calc_rto(clnt->cl_rtt, timer);
- task->tk_timeout <<= rpc_ntimeo(clnt->cl_rtt, timer) + req->rq_retries;
- if (task->tk_timeout > xprt->timeout.to_maxval || task->tk_timeout == 0)
- task->tk_timeout = xprt->timeout.to_maxval;
- } else
- task->tk_timeout = req->rq_timeout;
+
+ xprt->ops->set_retrans_timeout(task);
+
+ xprt->stat.sends++;
+ xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs;
+ xprt->stat.bklog_u += xprt->backlog.qlen;
+
/* Don't race with disconnect */
if (!xprt_connected(xprt))
task->tk_status = -ENOTCONN;
- else if (!req->rq_received)
- rpc_sleep_on(&xprt->pending, task, NULL, xprt_timer);
- __xprt_release_write(xprt, task);
+ else if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) {
+ /*
+ * Sleep on the pending queue since
+ * we're expecting a reply.
+ */
+ rpc_sleep_on(&xprt->pending, task, xprt_timer);
+ }
spin_unlock_bh(&xprt->transport_lock);
}
-static inline void do_xprt_reserve(struct rpc_task *task)
+static void xprt_alloc_slot(struct rpc_task *task)
{
struct rpc_xprt *xprt = task->tk_xprt;
xprt_request_init(task, xprt);
return;
}
- dprintk("RPC: waiting for request slot\n");
+ dprintk("RPC: waiting for request slot\n");
task->tk_status = -EAGAIN;
task->tk_timeout = 0;
- rpc_sleep_on(&xprt->backlog, task, NULL, NULL);
+ rpc_sleep_on(&xprt->backlog, task, NULL);
+}
+
+static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req)
+{
+ memset(req, 0, sizeof(*req)); /* mark unused */
+
+ spin_lock(&xprt->reserve_lock);
+ list_add(&req->rq_list, &xprt->free);
+ rpc_wake_up_next(&xprt->backlog);
+ spin_unlock(&xprt->reserve_lock);
}
/**
struct rpc_xprt *xprt = task->tk_xprt;
task->tk_status = -EIO;
- if (!xprt->shutdown) {
- spin_lock(&xprt->reserve_lock);
- do_xprt_reserve(task);
- spin_unlock(&xprt->reserve_lock);
- }
+ spin_lock(&xprt->reserve_lock);
+ xprt_alloc_slot(task);
+ spin_unlock(&xprt->reserve_lock);
}
-static inline u32 xprt_alloc_xid(struct rpc_xprt *xprt)
+static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt)
{
- return xprt->xid++;
+ return (__force __be32)xprt->xid++;
}
static inline void xprt_init_xid(struct rpc_xprt *xprt)
{
- get_random_bytes(&xprt->xid, sizeof(xprt->xid));
+ xprt->xid = net_random();
}
static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt)
{
struct rpc_rqst *req = task->tk_rqstp;
- req->rq_timeout = xprt->timeout.to_initval;
+ req->rq_timeout = task->tk_client->cl_timeout->to_initval;
req->rq_task = task;
req->rq_xprt = xprt;
+ req->rq_buffer = NULL;
req->rq_xid = xprt_alloc_xid(xprt);
- dprintk("RPC: %4d reserved req %p xid %08x\n", task->tk_pid,
+ req->rq_release_snd_buf = NULL;
+ xprt_reset_majortimeo(req);
+ dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid,
req, ntohl(req->rq_xid));
}
*/
void xprt_release(struct rpc_task *task)
{
- struct rpc_xprt *xprt = task->tk_xprt;
+ struct rpc_xprt *xprt;
struct rpc_rqst *req;
if (!(req = task->tk_rqstp))
return;
+
+ xprt = req->rq_xprt;
+ rpc_count_iostats(task);
spin_lock_bh(&xprt->transport_lock);
- __xprt_release_write(xprt, task);
- __xprt_put_cong(xprt, req);
+ xprt->ops->release_xprt(xprt, task);
+ if (xprt->ops->release_request)
+ xprt->ops->release_request(task);
if (!list_empty(&req->rq_list))
list_del(&req->rq_list);
xprt->last_used = jiffies;
- if (list_empty(&xprt->recv) && !xprt->shutdown)
+ if (list_empty(&xprt->recv) && xprt_has_timer(xprt))
mod_timer(&xprt->timer,
- xprt->last_used + RPC_IDLE_DISCONNECT_TIMEOUT);
+ xprt->last_used + xprt->idle_timeout);
spin_unlock_bh(&xprt->transport_lock);
+ if (req->rq_buffer)
+ xprt->ops->buf_free(req->rq_buffer);
task->tk_rqstp = NULL;
- memset(req, 0, sizeof(*req)); /* mark unused */
+ if (req->rq_release_snd_buf)
+ req->rq_release_snd_buf(req);
- dprintk("RPC: %4d release request %p\n", task->tk_pid, req);
-
- spin_lock(&xprt->reserve_lock);
- list_add(&req->rq_list, &xprt->free);
- xprt_clear_backlog(xprt);
- spin_unlock(&xprt->reserve_lock);
+ dprintk("RPC: %5u release request %p\n", task->tk_pid, req);
+ if (likely(!bc_prealloc(req)))
+ xprt_free_slot(xprt, req);
+ else
+ xprt_free_bc_request(req);
}
/**
- * xprt_set_timeout - set constant RPC timeout
- * @to: RPC timeout parameters to set up
- * @retr: number of retries
- * @incr: amount of increase after each retry
+ * xprt_create_transport - create an RPC transport
+ * @args: rpc transport creation arguments
*
*/
-void xprt_set_timeout(struct rpc_timeout *to, unsigned int retr, unsigned long incr)
+struct rpc_xprt *xprt_create_transport(struct xprt_create *args)
{
- to->to_initval =
- to->to_increment = incr;
- to->to_maxval = to->to_initval + (incr * retr);
- to->to_retries = retr;
- to->to_exponential = 0;
-}
-
-static struct rpc_xprt *xprt_setup(int proto, struct sockaddr_in *ap, struct rpc_timeout *to)
-{
- int result;
struct rpc_xprt *xprt;
struct rpc_rqst *req;
+ struct xprt_class *t;
- if ((xprt = kmalloc(sizeof(struct rpc_xprt), GFP_KERNEL)) == NULL)
- return ERR_PTR(-ENOMEM);
- memset(xprt, 0, sizeof(*xprt)); /* Nnnngh! */
-
- xprt->addr = *ap;
-
- switch (proto) {
- case IPPROTO_UDP:
- result = xs_setup_udp(xprt, to);
- break;
- case IPPROTO_TCP:
- result = xs_setup_tcp(xprt, to);
- break;
- default:
- printk(KERN_ERR "RPC: unrecognized transport protocol: %d\n",
- proto);
- result = -EIO;
- break;
+ spin_lock(&xprt_list_lock);
+ list_for_each_entry(t, &xprt_list, list) {
+ if (t->ident == args->ident) {
+ spin_unlock(&xprt_list_lock);
+ goto found;
+ }
}
- if (result) {
- kfree(xprt);
- return ERR_PTR(result);
+ spin_unlock(&xprt_list_lock);
+ printk(KERN_ERR "RPC: transport (%d) not supported\n", args->ident);
+ return ERR_PTR(-EIO);
+
+found:
+ xprt = t->setup(args);
+ if (IS_ERR(xprt)) {
+ dprintk("RPC: xprt_create_transport: failed, %ld\n",
+ -PTR_ERR(xprt));
+ return xprt;
}
+ kref_init(&xprt->kref);
spin_lock_init(&xprt->transport_lock);
spin_lock_init(&xprt->reserve_lock);
- init_waitqueue_head(&xprt->cong_wait);
INIT_LIST_HEAD(&xprt->free);
INIT_LIST_HEAD(&xprt->recv);
- INIT_WORK(&xprt->task_cleanup, xprt_autoclose, xprt);
- init_timer(&xprt->timer);
- xprt->timer.function = xprt_init_autodisconnect;
- xprt->timer.data = (unsigned long) xprt;
+#if defined(CONFIG_NFS_V4_1)
+ spin_lock_init(&xprt->bc_pa_lock);
+ INIT_LIST_HEAD(&xprt->bc_pa_list);
+#endif /* CONFIG_NFS_V4_1 */
+
+ INIT_WORK(&xprt->task_cleanup, xprt_autoclose);
+ if (xprt_has_timer(xprt))
+ setup_timer(&xprt->timer, xprt_init_autodisconnect,
+ (unsigned long)xprt);
+ else
+ init_timer(&xprt->timer);
xprt->last_used = jiffies;
+ xprt->cwnd = RPC_INITCWND;
+ xprt->bind_index = 0;
+ rpc_init_wait_queue(&xprt->binding, "xprt_binding");
rpc_init_wait_queue(&xprt->pending, "xprt_pending");
rpc_init_wait_queue(&xprt->sending, "xprt_sending");
rpc_init_wait_queue(&xprt->resend, "xprt_resend");
xprt_init_xid(xprt);
- dprintk("RPC: created transport %p with %u slots\n", xprt,
+ dprintk("RPC: created transport %p with %u slots\n", xprt,
xprt->max_reqs);
-
return xprt;
}
/**
- * xprt_create_proto - create an RPC client transport
- * @proto: requested transport protocol
- * @sap: remote peer's address
- * @to: timeout parameters for new transport
+ * xprt_destroy - destroy an RPC transport, killing off all requests.
+ * @kref: kref for the transport to destroy
*
*/
-struct rpc_xprt *xprt_create_proto(int proto, struct sockaddr_in *sap, struct rpc_timeout *to)
+static void xprt_destroy(struct kref *kref)
{
- struct rpc_xprt *xprt;
+ struct rpc_xprt *xprt = container_of(kref, struct rpc_xprt, kref);
- xprt = xprt_setup(proto, sap, to);
- if (IS_ERR(xprt))
- dprintk("RPC: xprt_create_proto failed\n");
- else
- dprintk("RPC: xprt_create_proto created xprt %p\n", xprt);
- return xprt;
-}
-
-static void xprt_shutdown(struct rpc_xprt *xprt)
-{
+ dprintk("RPC: destroying transport %p\n", xprt);
xprt->shutdown = 1;
- rpc_wake_up(&xprt->sending);
- rpc_wake_up(&xprt->resend);
- xprt_wake_pending_tasks(xprt, -EIO);
- rpc_wake_up(&xprt->backlog);
- wake_up(&xprt->cong_wait);
del_timer_sync(&xprt->timer);
-}
-static int xprt_clear_backlog(struct rpc_xprt *xprt) {
- rpc_wake_up_next(&xprt->backlog);
- wake_up(&xprt->cong_wait);
- return 1;
+ rpc_destroy_wait_queue(&xprt->binding);
+ rpc_destroy_wait_queue(&xprt->pending);
+ rpc_destroy_wait_queue(&xprt->sending);
+ rpc_destroy_wait_queue(&xprt->resend);
+ rpc_destroy_wait_queue(&xprt->backlog);
+ /*
+ * Tear down transport state and free the rpc_xprt
+ */
+ xprt->ops->destroy(xprt);
}
/**
- * xprt_destroy - destroy an RPC transport, killing off all requests.
- * @xprt: transport to destroy
+ * xprt_put - release a reference to an RPC transport.
+ * @xprt: pointer to the transport
*
*/
-int xprt_destroy(struct rpc_xprt *xprt)
+void xprt_put(struct rpc_xprt *xprt)
{
- dprintk("RPC: destroying transport %p\n", xprt);
- xprt_shutdown(xprt);
- xprt->ops->destroy(xprt);
- kfree(xprt);
+ kref_put(&xprt->kref, xprt_destroy);
+}
- return 0;
+/**
+ * xprt_get - return a reference to an RPC transport.
+ * @xprt: pointer to the transport
+ *
+ */
+struct rpc_xprt *xprt_get(struct rpc_xprt *xprt)
+{
+ kref_get(&xprt->kref);
+ return xprt;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff