[RFC PATCH 05/19] cpufreq: assert locking when accessing cpufreq_policy_list

From: Juri Lelli
Date: Mon Jan 11 2016 - 12:41:41 EST


cpufreq_policy_list is guarded by cpufreq_driver_lock. Add appropriate
locking assertions to check that we always access the list while holding
the associated lock.

Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Signed-off-by: Juri Lelli <juri.lelli@xxxxxxx>
---
drivers/cpufreq/cpufreq.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 00a00cd..63d6efb 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -65,6 +65,7 @@ static bool suitable_policy(struct cpufreq_policy *policy, bool active)
static struct cpufreq_policy *next_policy(struct cpufreq_policy *policy,
bool active)
{
+ lockdep_assert_held(&cpufreq_driver_lock);
do {
policy = list_next_entry(policy, policy_list);

@@ -80,6 +81,7 @@ static struct cpufreq_policy *first_policy(bool active)
{
struct cpufreq_policy *policy;

+ lockdep_assert_held(&cpufreq_driver_lock);
/* No policies in the list */
if (list_empty(&cpufreq_policy_list))
return NULL;
@@ -2430,6 +2432,7 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
if (ret)
goto err_boost_unreg;

+ lockdep_assert_held(&cpufreq_driver_lock);
if (!(cpufreq_driver->flags & CPUFREQ_STICKY) &&
list_empty(&cpufreq_policy_list)) {
/* if all ->init() calls failed, unregister */
--
2.2.2