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

From: Frederic Weisbecker
Date: Mon Nov 06 2017 - 10:02:00 EST


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@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
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