[tip:locking/core] timers/nohz: Use lockdep to assert IRQs are disabled/enabled

From: tip-bot for Frederic Weisbecker
Date: Wed Nov 08 2017 - 05:57:51 EST


Commit-ID: ebf3adbad012b89c4a51a3beae718a587d988a3a
Gitweb: https://git.kernel.org/tip/ebf3adbad012b89c4a51a3beae718a587d988a3a
Author: Frederic Weisbecker <frederic@xxxxxxxxxx>
AuthorDate: Mon, 6 Nov 2017 16:01:20 +0100
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 8 Nov 2017 11:13:49 +0100

timers/nohz: 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@xxxxxxxxxx>
Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: David S . Miller <davem@xxxxxxxxxxxxx>
Cc: Lai Jiangshan <jiangshanlai@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1509980490-4285-5-git-send-email-frederic@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
kernel/time/tick-sched.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index c7a899c..dd4b7b4 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -198,7 +198,7 @@ static bool check_tick_dependency(atomic_t *dep)

static bool can_stop_full_tick(int cpu, struct tick_sched *ts)
{
- WARN_ON_ONCE(!irqs_disabled());
+ lockdep_assert_irqs_disabled();

if (unlikely(!cpu_online(cpu)))
return false;
@@ -960,8 +960,7 @@ void tick_nohz_idle_enter(void)
{
struct tick_sched *ts;

- WARN_ON_ONCE(irqs_disabled());
-
+ lockdep_assert_irqs_enabled();
/*
* Update the idle state in the scheduler domain hierarchy
* when tick_nohz_stop_sched_tick() is called from the idle loop.