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 <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Viresh Kumar 2017-01-23 10:11:46 +05:30 committed by Rafael J. Wysocki
parent b83c1899a0
commit 7034764a1e
3 changed files with 18 additions and 15 deletions

View File

@ -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);

View File

@ -16,6 +16,7 @@
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/limits.h>
#include <linux/pm_opp.h>
@ -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;

View File

@ -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)
{