rcu: Rename struct rcu_data .exp_dynticks_snap into .exp_watching_snap

The context_tracking.state RCU_DYNTICKS subvariable has been renamed to
RCU_WATCHING, and the snapshot helpers are now prefix by
"rcu_watching". Reflect that change into the storage variables for these
snapshots.
Signed-off-by: Valentin Schneider <vschneid@redhat.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>

kernel/rcu/tree.h

@@ -215,7 +215,7 @@ struct rcu_data {
 	/* 4) rcu_barrier(), OOM callbacks, and expediting. */
 	unsigned long barrier_seq_snap;	/* Snap of rcu_state.barrier_sequence. */
 	struct rcu_head barrier_head;
-	int exp_dynticks_snap;		/* Double-check need for IPI. */
+	int exp_watching_snap;		/* Double-check need for IPI. */
 
 	/* 5) Callback offloading. */
 #ifdef CONFIG_RCU_NOCB_CPU

kernel/rcu/tree_exp.h

@@ -380,7 +380,7 @@ static void __sync_rcu_exp_select_node_cpus(struct rcu_exp_work *rewp)
 			if (rcu_watching_snap_in_eqs(snap))
 				mask_ofl_test |= mask;
 			else
-				rdp->exp_dynticks_snap = snap;
+				rdp->exp_watching_snap = snap;
 		}
 	}
 	mask_ofl_ipi = rnp->expmask & ~mask_ofl_test;
@@ -400,7 +400,7 @@ static void __sync_rcu_exp_select_node_cpus(struct rcu_exp_work *rewp)
 		unsigned long mask = rdp->grpmask;
 
 retry_ipi:
-		if (rcu_watching_snap_stopped_since(rdp, rdp->exp_dynticks_snap)) {
+		if (rcu_watching_snap_stopped_since(rdp, rdp->exp_watching_snap)) {
 			mask_ofl_test |= mask;
 			continue;
 		}