[PATCH] RCU: Adjust comments for force_qs_rnp

[Zhouyi Zhou <zhouzhouyi@gmail.com>]

Previously, threads blocked on offlining CPUS are migrated to root
rcu_node, so there is a need to initiate RCU priority boosting on root
rcu_node,

Current RCU does not migrate blocked tasks even if all corresponding CPUs
offline. 
commit d19fb8d1f3f6 ("rcu: Don't migrate blocked tasks even if all corresponding CPUs offline")'

Consequently, rcu does not initiate RCU priority boosting on root rcu_node.
commit 1be0085b515e ("rcu: Don't initiate RCU priority boosting on root rcu_node")'

So I think the comments for force_qs_rnp should be adjusted.

Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
---
 kernel/rcu/tree.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index acd6ccf..efddffb 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -2548,9 +2548,9 @@ void rcu_sched_clock_irq(int user)
 }
 
 /*
- * Scan the leaf rcu_node structures, processing dyntick state for any that
- * have not yet encountered a quiescent state, using the function specified.
- * Also initiate boosting for any threads blocked on the root rcu_node.
+ * Scan the leaf rcu_node structures, initiating boost for any threads blocked
+ * on them, processing dyntick state for any that have not yet encountered a
+ * quiescent state, using the function specified.
  *
  * The caller must have suppressed start of new grace periods.
  */
-- 
2.1.4