From 7034764a1e4a6edbb60914e89aad8384e3fe5d17 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Mon, 23 Jan 2017 10:11:46 +0530 Subject: [PATCH] PM / OPP: Add 'struct kref' to struct dev_pm_opp Add kref to struct dev_pm_opp for easier accounting of the OPPs. Note that the OPPs are freed under the opp_table->lock mutex only. Signed-off-by: Viresh Kumar Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp/core.c | 27 ++++++++++++--------------- drivers/base/power/opp/opp.h | 3 +++ include/linux/pm_opp.h | 3 +++ 3 files changed, 18 insertions(+), 15 deletions(-) diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index ab9499e3ba02..9870ee54d708 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -949,20 +949,10 @@ static void _kfree_opp_rcu(struct rcu_head *head) kfree_rcu(opp, rcu_head); } -/** - * _opp_remove() - Remove an OPP from a table definition - * @opp_table: points back to the opp_table struct this opp belongs to - * @opp: pointer to the OPP to remove - * - * This function removes an opp definition from the opp table. - * - * Locking: The internal opp_table and opp structures are RCU protected. - * It is assumed that the caller holds required mutex for an RCU updater - * strategy. - */ -static void _opp_remove(struct opp_table *opp_table, struct dev_pm_opp *opp) +static void _opp_kref_release(struct kref *kref) { - mutex_lock(&opp_table->lock); + struct dev_pm_opp *opp = container_of(kref, struct dev_pm_opp, kref); + struct opp_table *opp_table = opp->opp_table; /* * Notify the changes in the availability of the operable @@ -977,6 +967,12 @@ static void _opp_remove(struct opp_table *opp_table, struct dev_pm_opp *opp) dev_pm_opp_put_opp_table(opp_table); } +void dev_pm_opp_put(struct dev_pm_opp *opp) +{ + kref_put_mutex(&opp->kref, _opp_kref_release, &opp->opp_table->lock); +} +EXPORT_SYMBOL_GPL(dev_pm_opp_put); + /** * dev_pm_opp_remove() - Remove an OPP from OPP table * @dev: device for which we do this operation @@ -1020,7 +1016,7 @@ void dev_pm_opp_remove(struct device *dev, unsigned long freq) goto unlock; } - _opp_remove(opp_table, opp); + dev_pm_opp_put(opp); unlock: mutex_unlock(&opp_table_lock); } @@ -1124,6 +1120,7 @@ int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, mutex_unlock(&opp_table->lock); new_opp->opp_table = opp_table; + kref_init(&new_opp->kref); /* Get a reference to the OPP table */ _get_opp_table_kref(opp_table); @@ -1819,7 +1816,7 @@ void _dev_pm_opp_remove_table(struct opp_table *opp_table, struct device *dev, /* Free static OPPs */ list_for_each_entry_safe(opp, tmp, &opp_table->opp_list, node) { if (remove_all || !opp->dynamic) - _opp_remove(opp_table, opp); + dev_pm_opp_put(opp); } } else { _remove_opp_dev(_find_opp_dev(dev, opp_table), opp_table); diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h index a01724363347..586f36f94e28 100644 --- a/drivers/base/power/opp/opp.h +++ b/drivers/base/power/opp/opp.h @@ -16,6 +16,7 @@ #include #include +#include #include #include #include @@ -56,6 +57,7 @@ extern struct list_head opp_tables; * are protected by the opp_table_lock for integrity. * IMPORTANT: the opp nodes should be maintained in increasing * order. + * @kref: for reference count of the OPP. * @available: true/false - marks if this OPP as available or not * @dynamic: not-created from static DT entries. * @turbo: true if turbo (boost) OPP @@ -73,6 +75,7 @@ extern struct list_head opp_tables; */ struct dev_pm_opp { struct list_head node; + struct kref kref; bool available; bool dynamic; diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index 99787cbcaab2..731d548657aa 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -102,6 +102,7 @@ struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev, struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev, unsigned long *freq); +void dev_pm_opp_put(struct dev_pm_opp *opp); int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt); @@ -193,6 +194,8 @@ static inline struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev, return ERR_PTR(-ENOTSUPP); } +static inline void dev_pm_opp_put(struct dev_pm_opp *opp) {} + static inline int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) { -- 2.30.2