From: Lai Jiangshan <laijs@cn.fujitsu.com>

When callbacks are moved from offline cpu to this cpu, the qlen field of
this rdp should be updated.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/rcuclassic.c |    4 ++++
 1 file changed, 4 insertions(+)

diff -puN kernel/rcuclassic.c~rcu-classic-update-qlen-when-cpu-offline kernel/rcuclassic.c
--- a/kernel/rcuclassic.c~rcu-classic-update-qlen-when-cpu-offline
+++ a/kernel/rcuclassic.c
@@ -373,6 +373,10 @@ static void __rcu_offline_cpu(struct rcu
 	rcu_move_batch(this_rdp, rdp->donelist, rdp->donetail);
 	rcu_move_batch(this_rdp, rdp->curlist, rdp->curtail);
 	rcu_move_batch(this_rdp, rdp->nxtlist, rdp->nxttail);
+
+	local_irq_disable();
+	this_rdp->qlen += rdp->qlen;
+	local_irq_enable();
 }
 
 static void rcu_offline_cpu(int cpu)
_