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);
+/*
+ * 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.
+ */
+#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_reserve_xprt - serialize write access to transports
return 0;
}
+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
+ schedule_work(&xprt->task_cleanup);
+}
+
/*
* xprt_reserve_xprt_cong - serialize write access to transports
* @task: task that is requesting access to the transport
}
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);
task->tk_timeout = 0;
return;
out_unlock:
- smp_mb__before_clear_bit();
- clear_bit(XPRT_LOCKED, &xprt->state);
- smp_mb__after_clear_bit();
+ xprt_clear_locked(xprt);
}
static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt)
return;
}
out_unlock:
- smp_mb__before_clear_bit();
- clear_bit(XPRT_LOCKED, &xprt->state);
- smp_mb__after_clear_bit();
+ xprt_clear_locked(xprt);
}
/**
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);
}
}
void xprt_release_xprt_cong(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_cong(xprt);
}
}
__xprt_lock_write_next_cong(xprt);
}
+/**
+ * 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);
+}
+
/**
* xprt_adjust_cwnd - adjust transport congestion window
* @task: recently completed RPC request used to adjust window
dprintk("RPC: %4d 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;
return;
if (task->tk_rqstp)
task->tk_rqstp->rq_bytes_sent = 0;
- task->tk_timeout = RPC_CONNECT_TIMEOUT;
+ task->tk_timeout = xprt->connect_timeout;
rpc_sleep_on(&xprt->pending, task, xprt_connect_status, NULL);
xprt->ops->connect(task);
}
dprintk("RPC: %4d xprt_prepare_transmit\n", task->tk_pid);
- if (xprt->shutdown)
- return -EIO;
-
spin_lock_bh(&xprt->transport_lock);
if (req->rq_received && !req->rq_bytes_sent) {
err = req->rq_received;
return err;
}
+void
+xprt_abort_transmit(struct rpc_task *task)
+{
+ struct rpc_xprt *xprt = task->tk_xprt;
+
+ xprt_release_write(xprt, task);
+}
+
/**
* xprt_transmit - send an RPC request on a transport
* @task: controlling RPC task
switch (status) {
case -ECONNREFUSED:
- task->tk_timeout = RPC_REESTABLISH_TIMEOUT;
rpc_sleep_on(&xprt->sending, task, NULL, NULL);
case -EAGAIN:
case -ENOTCONN:
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);
+ do_xprt_reserve(task);
+ spin_unlock(&xprt->reserve_lock);
}
static inline u32 xprt_alloc_xid(struct rpc_xprt *xprt)
req->rq_timeout = xprt->timeout.to_initval;
req->rq_task = task;
req->rq_xprt = xprt;
+ req->rq_buffer = NULL;
+ req->rq_bufsize = 0;
req->rq_xid = xprt_alloc_xid(xprt);
+ req->rq_release_snd_buf = NULL;
dprintk("RPC: %4d reserved req %p xid %08x\n", task->tk_pid,
req, ntohl(req->rq_xid));
}
return;
spin_lock_bh(&xprt->transport_lock);
xprt->ops->release_xprt(xprt, task);
- __xprt_put_cong(xprt, req);
+ 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))
mod_timer(&xprt->timer,
- xprt->last_used + RPC_IDLE_DISCONNECT_TIMEOUT);
+ xprt->last_used + xprt->idle_timeout);
spin_unlock_bh(&xprt->transport_lock);
+ xprt->ops->buf_free(task);
task->tk_rqstp = NULL;
+ if (req->rq_release_snd_buf)
+ req->rq_release_snd_buf(req);
memset(req, 0, sizeof(*req)); /* mark unused */
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);
+ rpc_wake_up_next(&xprt->backlog);
spin_unlock(&xprt->reserve_lock);
}
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);
xprt->timer.function = xprt_init_autodisconnect;
xprt->timer.data = (unsigned long) xprt;
xprt->last_used = jiffies;
+ xprt->cwnd = RPC_INITCWND;
rpc_init_wait_queue(&xprt->pending, "xprt_pending");
rpc_init_wait_queue(&xprt->sending, "xprt_sending");
return xprt;
}
-static void xprt_shutdown(struct rpc_xprt *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;
-}
-
/**
* xprt_destroy - destroy an RPC transport, killing off all requests.
* @xprt: transport to destroy
int xprt_destroy(struct rpc_xprt *xprt)
{
dprintk("RPC: destroying transport %p\n", xprt);
- xprt_shutdown(xprt);
+ xprt->shutdown = 1;
+ del_timer_sync(&xprt->timer);
xprt->ops->destroy(xprt);
kfree(xprt);
projects / linux-2.6 / blobdiff