From 696a02cc16b182dd78b1f395ae336f449cc90f11 Mon Sep 17 00:00:00 2001
From: "Paul E. McKenney" <paul.mckenney@linaro.org>
Date: Thu, 16 Feb 2012 21:59:33 -0800
Subject: [PATCH] rcu: Hold off RCU_FAST_NO_HZ after timer posted

This commit handles workloads that transition quickly between idle and
non-idle, and where the CPU's callbacks cannot be invoked, but where
RCU does not have anything immediate for the CPU to do.  Without this
patch, the RCU_FAST_NO_HZ code can be invoked repeatedly on each entry
to idle.  The commit sets the per-CPU rcu_dyntick_holdoff variable to
hold off further attempts for a tick.

Reported-by: "Abou Gazala, Neven M" <neven.m.abou.gazala@intel.com>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
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