From: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Date: Mon, 9 Feb 2015 13:37:47 +0000 (-0800)
Subject: rcu: Add diagnostics to grace-period cleanup
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=5c60d25fa1b22fdcf141f8006d31c32b08db7311;p=linux-beck.git

rcu: Add diagnostics to grace-period cleanup

At grace-period initialization time, RCU checks that all quiescent
states were really reported for the previous grace period.  Now that
grace-period cleanup has been split out of grace-period initialization,
this commit also performs those checks at grace-period cleanup time.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index d5247ed44004..17b5abf999ca 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -1920,6 +1920,8 @@ static void rcu_gp_cleanup(struct rcu_state *rsp)
 	rcu_for_each_node_breadth_first(rsp, rnp) {
 		raw_spin_lock_irq(&rnp->lock);
 		smp_mb__after_unlock_lock();
+		WARN_ON_ONCE(rcu_preempt_blocked_readers_cgp(rnp));
+		WARN_ON_ONCE(rnp->qsmask);
 		ACCESS_ONCE(rnp->completed) = rsp->gpnum;
 		rdp = this_cpu_ptr(rsp->rda);
 		if (rnp == rdp->mynode)