SUNRPC: Add a new error code for retry waiting for another binder

Add new error code processing to the kernel's rpcbind client and to
call_bind_status() to distinguish two cases:

Case 1: the remote has replied that the program/version tuple is not
registered (returns -EACCES)

Case 2: another process is already in the middle of binding on this
transport (now returns -EAGAIN)

This change allows more specific retry processing for each of these two
cases.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 7a7cd3b..e53d718 100644 (file)
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -950,6 +950,12 @@ call_bind_status(struct rpc_task *task)
        }
 
        switch (task->tk_status) {
+       case -EAGAIN:
+               dprintk("RPC: %5u rpcbind waiting for another request "
+                               "to finish\n", task->tk_pid);
+               /* avoid busy-waiting here -- could be a network outage. */
+               rpc_delay(task, 5*HZ);
+               goto retry_timeout;
        case -EACCES:
                dprintk("RPC: %5u remote rpcbind: RPC program/version "
                                "unavailable\n", task->tk_pid);

diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c
index a0c9f69..9b06a21 100644 (file)
--- a/net/sunrpc/rpcb_clnt.c
+++ b/net/sunrpc/rpcb_clnt.c
@@ -341,7 +341,7 @@ void rpcb_getport_async(struct rpc_task *task)
        BUG_ON(clnt->cl_parent != clnt);
 
        if (xprt_test_and_set_binding(xprt)) {
-               status = -EACCES;               /* tell caller to check again */
+               status = -EAGAIN;       /* tell caller to check again */
                dprintk("RPC: %5u %s: waiting for another binder\n",
                        task->tk_pid, __FUNCTION__);
                goto bailout_nowake;