[PATCH 02/14] irq: Use lockdep to assert IRQs are disabled/enabled

From: Frederic Weisbecker <frederic@kernel.org>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>,
	Tejun Heo <tj@kernel.org>, Peter Zijlstra <peterz@infradead.org>,
	"David S . Miller" <davem@davemloft.net>,
	Lai Jiangshan <jiangshanlai@gmail.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"Paul E . McKenney" <paulmck@linux.vnet.ibm.com>,
	Ingo Molnar <mingo@kernel.org>
Subject: [PATCH 02/14] irq: Use lockdep to assert IRQs are disabled/enabled
Date: Fri, 20 Oct 2017 02:55:59 +0200	[thread overview]
Message-ID: <1508460971-8731-3-git-send-email-frederic@kernel.org> (raw)
In-Reply-To: <1508460971-8731-1-git-send-email-frederic@kernel.org>

Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
 kernel/softirq.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/kernel/softirq.c b/kernel/softirq.c
index 4e09821..662f7b1b 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -137,7 +137,7 @@ EXPORT_SYMBOL(__local_bh_disable_ip);
 
 static void __local_bh_enable(unsigned int cnt)
 {
-	WARN_ON_ONCE(!irqs_disabled());
+	lockdep_assert_irqs_disabled();
 
 	if (softirq_count() == (cnt & SOFTIRQ_MASK))
 		trace_softirqs_on(_RET_IP_);
@@ -158,7 +158,8 @@ EXPORT_SYMBOL(_local_bh_enable);
 
 void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
 {
-	WARN_ON_ONCE(in_irq() || irqs_disabled());
+	WARN_ON_ONCE(in_irq());
+	lockdep_assert_irqs_enabled();
 #ifdef CONFIG_TRACE_IRQFLAGS
 	local_irq_disable();
 #endif
@@ -396,9 +397,8 @@ void irq_exit(void)
 #ifndef __ARCH_IRQ_EXIT_IRQS_DISABLED
 	local_irq_disable();
 #else
-	WARN_ON_ONCE(!irqs_disabled());
+	lockdep_assert_irqs_disabled();
 #endif
-
 	account_irq_exit_time(current);
 	preempt_count_sub(HARDIRQ_OFFSET);
 	if (!in_interrupt() && local_softirq_pending())
@@ -488,7 +488,7 @@ EXPORT_SYMBOL(__tasklet_hi_schedule);
 
 void __tasklet_hi_schedule_first(struct tasklet_struct *t)
 {
-	BUG_ON(!irqs_disabled());
+	lockdep_assert_irqs_disabled();
 
 	t->next = __this_cpu_read(tasklet_hi_vec.head);
 	__this_cpu_write(tasklet_hi_vec.head, t);
-- 
2.7.4
