From: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Date: Wed, 12 Jul 2017 16:03:35 +0000 (-0700)
Subject: rcu: Add warning to rcu_idle_enter() for irqs enabled
X-Git-Tag: v4.14-rc1~174^2^2^2~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d4db30af51eb94ccfd0037e114c1c12cc299a3f8;p=thirdparty%2Fkernel%2Flinux.git

rcu: Add warning to rcu_idle_enter() for irqs enabled

All current callers of rcu_idle_enter() have irqs disabled, and
rcu_idle_enter() relies on this, but doesn't check.  This commit
therefore adds a RCU_LOCKDEP_WARN() to add some verification to the trust.
While we are there, pass "true" rather than "1" to rcu_eqs_enter().

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

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 76f88b65961f9..5f4eccac17010 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -859,7 +859,8 @@ EXPORT_SYMBOL_GPL(rcu_idle_enter);
  */
 void rcu_user_enter(void)
 {
-	rcu_eqs_enter(1);
+	RCU_LOCKDEP_WARN(!irqs_disabled(), "rcu_user_enter() invoked with irqs enabled!!!");
+	rcu_eqs_enter(true);
 }
 #endif /* CONFIG_NO_HZ_FULL */