rpc: add a new priority in RPC task

Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

include/linux/sunrpc/sched.h

@@ -173,7 +173,8 @@ struct rpc_task_setup {
 #define RPC_PRIORITY_LOW	(-1)
 #define RPC_PRIORITY_NORMAL	(0)
 #define RPC_PRIORITY_HIGH	(1)
-#define RPC_NR_PRIORITY		(1 + RPC_PRIORITY_HIGH - RPC_PRIORITY_LOW)
+#define RPC_PRIORITY_PRIVILEGED	(2)
+#define RPC_NR_PRIORITY		(1 + RPC_PRIORITY_PRIVILEGED - RPC_PRIORITY_LOW)
 
 struct rpc_timer {
 	struct timer_list timer;
@@ -255,6 +256,16 @@ static inline int rpc_wait_for_completion_task(struct rpc_task *task)
 	return __rpc_wait_for_completion_task(task, NULL);
 }
 
+static inline void rpc_task_set_priority(struct rpc_task *task, unsigned char prio)
+{
+	task->tk_priority = prio - RPC_PRIORITY_LOW;
+}
+
+static inline int rpc_task_has_priority(struct rpc_task *task, unsigned char prio)
+{
+	return (task->tk_priority + RPC_PRIORITY_LOW == prio);
+}
+
 #ifdef RPC_DEBUG
 static inline const char * rpc_qname(struct rpc_wait_queue *q)
 {