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>

1 files changed, 14 insertions, 12 deletions

diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index a74cb67f15bf..dd61cd02461f 100644
--- 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);