Certain OPP APIs need to be called under RCU lock; let's add a few rcu_lockdep_assert() calls to warn about potential misuse.
Signed-off-by: Dmitry Torokhov <[email protected]> --- drivers/base/power/opp.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index d24dd614a..b78c14d 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -108,6 +108,14 @@ static LIST_HEAD(dev_opp_list); /* Lock to allow exclusive modification to the device and opp lists */ static DEFINE_MUTEX(dev_opp_list_lock); +#define opp_rcu_lockdep_assert() \ +do { \ + rcu_lockdep_assert(rcu_read_lock_held() || \ + lockdep_is_held(&dev_opp_list_lock), \ + "Missing rcu_read_lock() or " \ + "dev_opp_list_lock protection"); \ +} while (0) + /** * find_device_opp() - find device_opp struct using device pointer * @dev: device pointer used to lookup device OPPs @@ -218,6 +226,8 @@ int dev_pm_opp_get_opp_count(struct device *dev) struct dev_pm_opp *temp_opp; int count = 0; + opp_rcu_lockdep_assert(); + dev_opp = find_device_opp(dev); if (IS_ERR(dev_opp)) { int r = PTR_ERR(dev_opp); @@ -267,6 +277,8 @@ struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev, struct device_opp *dev_opp; struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE); + opp_rcu_lockdep_assert(); + dev_opp = find_device_opp(dev); if (IS_ERR(dev_opp)) { int r = PTR_ERR(dev_opp); @@ -313,6 +325,8 @@ struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev, struct device_opp *dev_opp; struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE); + opp_rcu_lockdep_assert(); + if (!dev || !freq) { dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq); return ERR_PTR(-EINVAL); @@ -361,6 +375,8 @@ struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev, struct device_opp *dev_opp; struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE); + opp_rcu_lockdep_assert(); + if (!dev || !freq) { dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq); return ERR_PTR(-EINVAL); -- 2.2.0.rc0.207.ga3a616c -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
