SUNRPC: Fix transport accounting when caller specifies an rpc_xprt

Ensure that we do the required accounting for the round robin queue
when the caller to rpc_init_task() has passed in a transport to be
used.

Reported-by: Olga Kornievskaia <aglo@umich.edu>
Reported-by: Neil Brown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

3 files changed, 24 insertions, 23 deletions

diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index 4619098affa3..4e070e00c143 100644
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -164,6 +164,8 @@ void		rpc_shutdown_client(struct rpc_clnt *);
 void            rpc_release_client(struct rpc_clnt *);
 void            rpc_task_release_transport(struct rpc_task *);
 void            rpc_task_release_client(struct rpc_task *);
+struct rpc_xprt *rpc_task_get_xprt(struct rpc_clnt *clnt,
+                struct rpc_xprt *xprt);
 
 int             rpcb_create_local(struct net *);
 void            rpcb_put_local(struct net *);
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index d599fab8adcb..383555d2b522 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -978,11 +978,10 @@ out:
 }
 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
 
-static struct rpc_xprt *
-rpc_task_get_xprt(struct rpc_clnt *clnt)
+struct rpc_xprt *
+rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
 {
         struct rpc_xprt_switch *xps;
-        struct rpc_xprt *xprt= xprt_iter_get_next(&clnt->cl_xpi);
 
         if (!xprt)
                 return NULL;
@@ -995,24 +994,6 @@ rpc_task_get_xprt(struct rpc_clnt *clnt)
         return xprt;
 }
 
-static struct rpc_xprt *
-rpc_task_get_first_xprt(struct rpc_clnt *clnt)
-{
-        struct rpc_xprt_switch *xps;
-        struct rpc_xprt *xprt;
-
-        rcu_read_lock();
-        xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
-        if (xprt) {
-                atomic_long_inc(&xprt->queuelen);
-                xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
-                atomic_long_inc(&xps->xps_queuelen);
-        }
-        rcu_read_unlock();
-
-        return xprt;
-}
-
 static void
 rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
 {
@@ -1057,6 +1038,23 @@ void rpc_task_release_client(struct rpc_task *task)
         }
 }
 
+static struct rpc_xprt *
+rpc_task_get_first_xprt(struct rpc_clnt *clnt)
+{
+        struct rpc_xprt *xprt;
+
+        rcu_read_lock();
+        xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
+        rcu_read_unlock();
+        return rpc_task_get_xprt(clnt, xprt);
+}
+
+static struct rpc_xprt *
+rpc_task_get_next_xprt(struct rpc_clnt *clnt)
+{
+        return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi));
+}
+
 static
 void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
 {
@@ -1065,7 +1063,7 @@ void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
         if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
                 task->tk_xprt = rpc_task_get_first_xprt(clnt);
         else
-                task->tk_xprt = rpc_task_get_xprt(clnt);
+                task->tk_xprt = rpc_task_get_next_xprt(clnt);
 }
 
 static
diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index 8a0779e963f9..1f275aba786f 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -1092,7 +1092,8 @@ static void rpc_init_task(struct rpc_task *task, const struct rpc_task_setup *ta
         /* Initialize workqueue for async tasks */
         task->tk_workqueue = task_setup_data->workqueue;
 
-        task->tk_xprt = xprt_get(task_setup_data->rpc_xprt);
+        task->tk_xprt = rpc_task_get_xprt(task_setup_data->rpc_client,
+                        xprt_get(task_setup_data->rpc_xprt));
 
         task->tk_op_cred = get_rpccred(task_setup_data->rpc_op_cred);