From: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Date: Sun, 10 Mar 2013 22:44:52 +0000 (-0700)
Subject: rcu: Tone down debugging during boot-up and shutdown.
X-Git-Tag: v3.10-rc1~175^2^2^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=81e59494a56cb14f559886c345c4a93fb576bbab;p=thirdparty%2Flinux.git

rcu: Tone down debugging during boot-up and shutdown.

In some situations, randomly delaying RCU grace-period initialization
can cause more trouble than help.  This commit therefore restricts this
type of RCU self-torture to runtime, giving it a rest during boot and
shutdown.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---

diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 71df6f9f5ce6a..0e522504ae37c 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -1319,7 +1319,8 @@ static int rcu_gp_init(struct rcu_state *rsp)
 					    rnp->grphi, rnp->qsmask);
 		raw_spin_unlock_irq(&rnp->lock);
 #ifdef CONFIG_PROVE_RCU_DELAY
-		if ((random32() % (rcu_num_nodes * 8)) == 0)
+		if ((random32() % (rcu_num_nodes * 8)) == 0 &&
+		    system_state == SYSTEM_RUNNING)
 			schedule_timeout_uninterruptible(2);
 #endif /* #ifdef CONFIG_PROVE_RCU_DELAY */
 		cond_resched();