SUNRPC: Return EAGAIN instead of ENOTCONN when waking up xprt->pending

While we should definitely return socket errors to the task that is
currently trying to send data, there is no need to propagate the same error
to all the other tasks on xprt->pending. Doing so actually slows down
recovery, since it causes more than one tasks to attempt socket recovery.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 31 insertions, 27 deletions

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 879af6f27b4..8e58b0b5460 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -1162,7 +1162,7 @@ static void xs_tcp_state_change(struct sock *sk)
                         transport->tcp_flags =
                                 TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
 
-                        xprt_wake_pending_tasks(xprt, 0);
+                        xprt_wake_pending_tasks(xprt, -EAGAIN);
                 }
                 spin_unlock_bh(&xprt->transport_lock);
                 break;
@@ -1721,20 +1721,22 @@ static void xs_tcp_connect_worker4(struct work_struct *work)
         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
                         xprt, -status, xprt_connected(xprt),
                         sock->sk->sk_state);
-        if (status < 0) {
-                switch (status) {
-                        case -EINPROGRESS:
-                        case -EALREADY:
-                                goto out_clear;
-                        case -ECONNREFUSED:
-                        case -ECONNRESET:
-                                /* retry with existing socket, after a delay */
-                                break;
-                        default:
-                                /* get rid of existing socket, and retry */
-                                xs_tcp_shutdown(xprt);
-                }
+        switch (status) {
+        case 0:
+        case -EINPROGRESS:
+        case -EALREADY:
+                goto out_clear;
+        case -ECONNREFUSED:
+        case -ECONNRESET:
+                /* retry with existing socket, after a delay */
+                break;
+        default:
+                /* get rid of existing socket, and retry */
+                xs_tcp_shutdown(xprt);
+                printk("%s: connect returned unhandled error %d\n",
+                                __func__, status);
         }
+        status = -EAGAIN;
 out:
         xprt_wake_pending_tasks(xprt, status);
 out_clear:
@@ -1780,20 +1782,22 @@ static void xs_tcp_connect_worker6(struct work_struct *work)
         status = xs_tcp_finish_connecting(xprt, sock);
         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
                         xprt, -status, xprt_connected(xprt), sock->sk->sk_state);
-        if (status < 0) {
-                switch (status) {
-                        case -EINPROGRESS:
-                        case -EALREADY:
-                                goto out_clear;
-                        case -ECONNREFUSED:
-                        case -ECONNRESET:
-                                /* retry with existing socket, after a delay */
-                                break;
-                        default:
-                                /* get rid of existing socket, and retry */
-                                xs_tcp_shutdown(xprt);
-                }
+        switch (status) {
+        case 0:
+        case -EINPROGRESS:
+        case -EALREADY:
+                goto out_clear;
+        case -ECONNREFUSED:
+        case -ECONNRESET:
+                /* retry with existing socket, after a delay */
+                break;
+        default:
+                /* get rid of existing socket, and retry */
+                xs_tcp_shutdown(xprt);
+                printk("%s: connect returned unhandled error %d\n",
+                                __func__, status);
         }
+        status = -EAGAIN;
 out:
         xprt_wake_pending_tasks(xprt, status);
 out_clear: