nfsd4: centralize more calls to svc_xprt_received

Follow up on b48fa6b99100dc7772af3cd276035fcec9719ceb by moving all the
svc_xprt_received() calls for the main xprt to one place.  The clearing
of XPT_BUSY here is critical to the correctness of the server, so I'd
prefer it to be obvious where we do it.

The only substantive result is moving svc_xprt_received() after
svc_receive_deferred().  Other than a (likely insignificant) delay
waking up the next thread, that should be harmless.

Also reshuffle the exit code a little to skip a few other steps that we
don't care about the in the svc_delete_xprt() case.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index a74cb67f15bf63884d06af8e1d4a0f30dbb466a0..dd61cd02461fb210ce085ca42d33249ccc97ca30 100644 (file)
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -716,7 +716,10 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
        if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) {
                dprintk("svc_recv: found XPT_CLOSE\n");
                svc_delete_xprt(xprt);
-       } else if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
+               /* Leave XPT_BUSY set on the dead xprt: */
+               goto out;
+       }
+       if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
                struct svc_xprt *newxpt;
                newxpt = xprt->xpt_ops->xpo_accept(xprt);
                if (newxpt) {
@@ -741,28 +744,23 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
                        spin_unlock_bh(&serv->sv_lock);
                        svc_xprt_received(newxpt);
                }
-               svc_xprt_received(xprt);
        } else {
                dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n",
                        rqstp, pool->sp_id, xprt,
                        atomic_read(&xprt->xpt_ref.refcount));
                rqstp->rq_deferred = svc_deferred_dequeue(xprt);
-               if (rqstp->rq_deferred) {
-                       svc_xprt_received(xprt);
+               if (rqstp->rq_deferred)
                        len = svc_deferred_recv(rqstp);
-               } else {
+               else
                        len = xprt->xpt_ops->xpo_recvfrom(rqstp);
-                       svc_xprt_received(xprt);
-               }
                dprintk("svc: got len=%d\n", len);
        }
+       svc_xprt_received(xprt);
 
        /* No data, incomplete (TCP) read, or accept() */
-       if (len == 0 || len == -EAGAIN) {
-               rqstp->rq_res.len = 0;
-               svc_xprt_release(rqstp);
-               return -EAGAIN;
-       }
+       if (len == 0 || len == -EAGAIN)
+               goto out;
+
        clear_bit(XPT_OLD, &xprt->xpt_flags);
 
        rqstp->rq_secure = svc_port_is_privileged(svc_addr(rqstp));
@@ -771,6 +769,10 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
        if (serv->sv_stats)
                serv->sv_stats->netcnt++;
        return len;
+out:
+       rqstp->rq_res.len = 0;
+       svc_xprt_release(rqstp);
+       return -EAGAIN;
 }
 EXPORT_SYMBOL_GPL(svc_recv);