rcu: Make expedited RCU CPU stall warnings respond to controls

The expedited RCU CPU stall warnings currently responds to neither the
panic_on_rcu_stall sysctl setting nor the rcupdate.rcu_cpu_stall_suppress
kernel boot parameter.  This commit therefore updates the expedited code
to respond to these two controls.

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

1 files changed, 3 insertions, 0 deletions

diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h
index 3a647eb96f23..f316683b18f1 100644
--- a/kernel/rcu/tree_exp.h
+++ b/kernel/rcu/tree_exp.h
@@ -428,6 +428,9 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
                 if (ret > 0 || sync_rcu_preempt_exp_done(rnp_root))
                         return;
                 WARN_ON(ret < 0);  /* workqueues should not be signaled. */
+                if (rcu_cpu_stall_suppress)
+                        continue;
+                panic_on_rcu_stall();
                 pr_err("INFO: %s detected expedited stalls on CPUs/tasks: {",
                        rsp->name);
                 ndetected = 0;