From c0356db7d1b66840882744cbd9d9c5960b2d88c7 Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Tue, 27 Jan 2015 21:13:42 +0100 Subject: PM / Domains: Eliminate the mutex for the generic_pm_domain_data While adding devices to their PM domains, dev_pm_qos_add_notifier() was invoked while allocating the generic_pm_domain_data for the device. Since the generic_pm_domain_data's device pointer will be assigned after allocation, the ->genpd_dev_pm_qos_notifier() callback could be called prior having a valid pointer to the device. Similar scenario existed while removing a device from a genpd. To cope with these scenarios a mutex was used to protect the pointer to the device. By re-order the sequence for when dev_pm_qos_add|remove_notifier() are invoked, we make sure the ->genpd_dev_pm_qos_notifier() callback are always called with a valid device pointer available. In this way, we eliminate the need for protecting the pointer and thus we can remove the mutex from the struct generic_pm_domain_data. Signed-off-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki --- include/linux/pm_domain.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux/pm_domain.h') diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index e160a0bba28d..080e778118ba 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -113,7 +113,6 @@ struct generic_pm_domain_data { struct pm_domain_data base; struct gpd_timing_data td; struct notifier_block nb; - struct mutex lock; int need_restore; }; -- cgit v1.2.2