From 1831b77dd44a8f638d78e23d9a6f2dcfe14d9ca5 Mon Sep 17 00:00:00 2001
From: Frederic Weisbecker <frederic@kernel.org>
Date: Mon, 6 Nov 2017 16:01:30 +0100
Subject: [PATCH] rcu: Use lockdep to assert IRQs are disabled/enabled

References: bnc#1068202 Avoid irqs_disabled debugging checks in fast paths
Patch-mainline: v4.15-rc1
Git-commit: b04db8e19fc2e9131524dec43057c1b96d5ba3ba

Backport note: This is a very limited backport. The upstream patches
	that added most of the assertions that this commit fixes were
	not backported.

Lockdep now has an integrated IRQs disabled/enabled sanity check. Just
use it instead of the ad-hoc RCU version.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-15-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
 kernel/rcu/tree.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 6354641c2f8f..41b052849555 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -899,7 +899,7 @@ void rcu_irq_exit(void)
 {
 	struct rcu_dynticks *rdtp;
 
-	RCU_LOCKDEP_WARN(!irqs_disabled(), "rcu_irq_exit() invoked with irqs enabled!!!");
+	lockdep_assert_irqs_disabled();
 	rdtp = this_cpu_ptr(&rcu_dynticks);
 
 	/* Page faults can happen in NMI handlers, so check... */
@@ -1031,7 +1031,7 @@ void rcu_irq_enter(void)
 	struct rcu_dynticks *rdtp;
 	long long oldval;
 
-	RCU_LOCKDEP_WARN(!irqs_disabled(), "rcu_irq_enter() invoked with irqs enabled!!!");
+	lockdep_assert_irqs_disabled();
 	rdtp = this_cpu_ptr(&rcu_dynticks);
 
 	/* Page faults can happen in NMI handlers, so check... */