[tip:locking/core] irq/softirqs: Use lockdep to assert IRQs are disabled/enabled

tip-bot for Frederic Weisbecker
2017-11-08T10:57:00Z

Commit-ID: f71b74bca637fca7de78f1d44eaefde5bc900f9f
Gitweb: https://git.kernel.org/tip/f71b74bca637fca7de78f1d44eaefde5bc900f9f
Author: Frederic Weisbecker <frederic@kernel.org>
AuthorDate: Mon, 6 Nov 2017 16:01:18 +0100
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Wed, 8 Nov 2017 11:13:48 +0100

irq/softirqs: Use lockdep to assert IRQs are disabled/enabled

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>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-3-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
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);