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>

1 files changed, 2 insertions, 0 deletions

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)