Commit da351878 authored by Chuck Lever's avatar Chuck Lever Committed by Trond Myklebust
Browse files

[PATCH] RPC: proper soft timeout behavior for rpcbind 



 Implement a best practice:  for soft mounts, an rpcbind timeout should
 cause an RPC request to fail.

 This also provides an FSM hook for retrying an rpcbind with a different
 rpcbind protocol version.  We'll use this later to try multiple rpcbind
 protocol versions when binding.  To enable this, expose the RPC error
 code returned during a portmap request to the FSM so it can make some
 decision about how to report, retry, or fail the request.

 Test-plan:
 Hundreds of passes with connectathon NFSv3 locking suite, on the client
 and server.

 Version: Thu, 11 Aug 2005 16:01:53 -0400

 Signed-off-by: default avatarChuck Lever <cel@netapp.com>
 Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent 23475d66

net/sunrpc/clnt.c

+77 −20
Original line number Diff line number Diff line
@@ -53,6 +53,7 @@ static void call_allocate(struct rpc_task *task); 
static void	call_encode(struct rpc_task *task);

static void	call_decode(struct rpc_task *task);

static void	call_bind(struct rpc_task *task);

static void	call_bind_status(struct rpc_task *task);

static void	call_transmit(struct rpc_task *task);

static void	call_status(struct rpc_task *task);

static void	call_refresh(struct rpc_task *task);
@@ -734,43 +735,94 @@ static void 
call_bind(struct rpc_task *task)

{

	struct rpc_clnt	*clnt = task->tk_client;

	struct rpc_xprt *xprt = clnt->cl_xprt;



	dprintk("RPC: %4d call_bind xprt %p %s connected\n", task->tk_pid,

			xprt, (xprt_connected(xprt) ? "is" : "is not"));



	task->tk_action = (xprt_connected(xprt)) ? call_transmit : call_connect;

	dprintk("RPC: %4d call_bind (status %d)\n",

				task->tk_pid, task->tk_status);



	if (!clnt->cl_port) {

	task->tk_action = call_connect;

	if (!clnt->cl_port) {

		task->tk_action = call_bind_status;

		task->tk_timeout = RPC_CONNECT_TIMEOUT;

		rpc_getport(task, clnt);

	}

}



/*

 * 4a.	Connect to the RPC server (TCP case)

 * 4a.	Sort out bind result

 */

static void

call_connect(struct rpc_task *task)

call_bind_status(struct rpc_task *task)

{

	struct rpc_clnt *clnt = task->tk_client;

	int status = -EACCES;



	dprintk("RPC: %4d call_connect status %d\n",

	if (task->tk_status >= 0) {

		dprintk("RPC: %4d call_bind_status (status %d)\n",

					task->tk_pid, task->tk_status);

		task->tk_status = 0;

		task->tk_action = call_connect;

		return;

	}



	if (xprt_connected(clnt->cl_xprt)) {

		task->tk_action = call_transmit;

	switch (task->tk_status) {

	case -EACCES:

		dprintk("RPC: %4d remote rpcbind: RPC program/version unavailable\n",

				task->tk_pid);

		break;

	case -ETIMEDOUT:

		dprintk("RPC: %4d rpcbind request timed out\n",

				task->tk_pid);

		if (RPC_IS_SOFT(task)) {

			status = -EIO;

			break;

		}

		goto retry_bind;

	case -EPFNOSUPPORT:

		dprintk("RPC: %4d remote rpcbind service unavailable\n",

				task->tk_pid);

		break;

	case -EPROTONOSUPPORT:

		dprintk("RPC: %4d remote rpcbind version 2 unavailable\n",

				task->tk_pid);

		break;

	default:

		dprintk("RPC: %4d unrecognized rpcbind error (%d)\n",

				task->tk_pid, -task->tk_status);

		status = -EIO;

		break;

	}



	rpc_exit(task, status);

	return;



retry_bind:

	task->tk_status = 0;

	task->tk_action = call_bind;

	return;

}



/*

 * 4b.	Connect to the RPC server

 */

static void

call_connect(struct rpc_task *task)

{

	struct rpc_xprt *xprt = task->tk_xprt;



	dprintk("RPC: %4d call_connect xprt %p %s connected\n",

			task->tk_pid, xprt,

			(xprt_connected(xprt) ? "is" : "is not"));



	task->tk_action = call_transmit;

	if (!xprt_connected(xprt)) {

		task->tk_action = call_connect_status;

		if (task->tk_status < 0)

			return;

		xprt_connect(task);

	}

}



/*

 * 4b. Sort out connect result

 * 4c.	Sort out connect result

 */

static void

call_connect_status(struct rpc_task *task)
@@ -778,6 +830,9 @@ call_connect_status(struct rpc_task *task) 
	struct rpc_clnt *clnt = task->tk_client;

	int status = task->tk_status;



	dprintk("RPC: %5u call_connect_status (status %d)\n", 

				task->tk_pid, task->tk_status);



	task->tk_status = 0;

	if (status >= 0) {

		clnt->cl_stats->netreconn++;
@@ -785,17 +840,19 @@ call_connect_status(struct rpc_task *task) 
		return;

	}



	/* Something failed: we may have to rebind */

	/* Something failed: remote service port may have changed */

	if (clnt->cl_autobind)

		clnt->cl_port = 0;



	switch (status) {

	case -ENOTCONN:

	case -ETIMEDOUT:

	case -EAGAIN:

		task->tk_action = (clnt->cl_port == 0) ? call_bind : call_connect;

		task->tk_action = call_bind;

		break;

	default:

		rpc_exit(task, -EIO);

		break;

	}

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE