PM / OPP: Don't allocate OPP table from _opp_allocate()

There is no point in trying to find/allocate the table for every OPP
that is added for a device. It would be far more efficient to allocate
the table only once and pass its pointer to the routines that add the
OPP entry.

Locking is removed from _opp_add_static_v2() and _opp_add_v1() now as
the callers call them with that lock already held.

Call to _remove_opp_table() routine is also removed from _opp_free()
now, as opp_table isn't allocated from within _opp_allocate(). This is
handled by the routines which created the OPP table in the first place.

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>

diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c
index b3a624a..dde7dd0 100644 (file)
--- a/drivers/base/power/opp/core.c
+++ b/drivers/base/power/opp/core.c
@@ -829,7 +829,7 @@ struct opp_device *_add_opp_dev(const struct device *dev,
  *
  * Return: valid opp_table pointer if success, else NULL.
  */
-static struct opp_table *_add_opp_table(struct device *dev)
+struct opp_table *_add_opp_table(struct device *dev)
 {
        struct opp_table *opp_table;
        struct opp_device *opp_dev;
@@ -929,10 +929,9 @@ static void _remove_opp_table(struct opp_table *opp_table)
                  _kfree_device_rcu);
 }
 
-void _opp_free(struct dev_pm_opp *opp, struct opp_table *opp_table)
+void _opp_free(struct dev_pm_opp *opp)
 {
        kfree(opp);
-       _remove_opp_table(opp_table);
 }
 
 /**
@@ -1016,16 +1015,10 @@ unlock:
 }
 EXPORT_SYMBOL_GPL(dev_pm_opp_remove);
 
-struct dev_pm_opp *_opp_allocate(struct device *dev,
-                                struct opp_table **opp_table)
+struct dev_pm_opp *_opp_allocate(struct opp_table *table)
 {
        struct dev_pm_opp *opp;
        int count, supply_size;
-       struct opp_table *table;
-
-       table = _add_opp_table(dev);
-       if (!table)
-               return NULL;
 
        /* Allocate space for at least one supply */
        count = table->regulator_count ? table->regulator_count : 1;
@@ -1033,17 +1026,13 @@ struct dev_pm_opp *_opp_allocate(struct device *dev,
 
        /* allocate new OPP node and supplies structures */
        opp = kzalloc(sizeof(*opp) + supply_size, GFP_KERNEL);
-       if (!opp) {
-               kfree(table);
+       if (!opp)
                return NULL;
-       }
 
        /* Put the supplies at the end of the OPP structure as an empty array */
        opp->supplies = (struct dev_pm_opp_supply *)(opp + 1);
        INIT_LIST_HEAD(&opp->node);
 
-       *opp_table = table;
-
        return opp;
 }
 
@@ -1133,6 +1122,7 @@ int _opp_add(struct device *dev, struct dev_pm_opp *new_opp,
 
 /**
  * _opp_add_v1() - Allocate a OPP based on v1 bindings.
+ * @opp_table: OPP table
  * @dev:       device for which we do this operation
  * @freq:      Frequency in Hz for this OPP
  * @u_volt:    Voltage in uVolts for this OPP
@@ -1158,22 +1148,18 @@ int _opp_add(struct device *dev, struct dev_pm_opp *new_opp,
  *             Duplicate OPPs (both freq and volt are same) and !opp->available
  * -ENOMEM     Memory allocation failure
  */
-int _opp_add_v1(struct device *dev, unsigned long freq, long u_volt,
-               bool dynamic)
+int _opp_add_v1(struct opp_table *opp_table, struct device *dev,
+               unsigned long freq, long u_volt, bool dynamic)
 {
-       struct opp_table *opp_table;
        struct dev_pm_opp *new_opp;
        unsigned long tol;
        int ret;
 
-       /* Hold our table modification lock here */
-       mutex_lock(&opp_table_lock);
+       opp_rcu_lockdep_assert();
 
-       new_opp = _opp_allocate(dev, &opp_table);
-       if (!new_opp) {
-               ret = -ENOMEM;
-               goto unlock;
-       }
+       new_opp = _opp_allocate(opp_table);
+       if (!new_opp)
+               return -ENOMEM;
 
        /* populate the opp table */
        new_opp->rate = freq;
@@ -1192,8 +1178,6 @@ int _opp_add_v1(struct device *dev, unsigned long freq, long u_volt,
                goto free_opp;
        }
 
-       mutex_unlock(&opp_table_lock);
-
        /*
         * Notify the changes in the availability of the operable
         * frequency/voltage list.
@@ -1202,9 +1186,8 @@ int _opp_add_v1(struct device *dev, unsigned long freq, long u_volt,
        return 0;
 
 free_opp:
-       _opp_free(new_opp, opp_table);
-unlock:
-       mutex_unlock(&opp_table_lock);
+       _opp_free(new_opp);
+
        return ret;
 }
 
@@ -1722,7 +1705,25 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_register_put_opp_helper);
  */
 int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt)
 {
-       return _opp_add_v1(dev, freq, u_volt, true);
+       struct opp_table *opp_table;
+       int ret;
+
+       /* Hold our table modification lock here */
+       mutex_lock(&opp_table_lock);
+
+       opp_table = _add_opp_table(dev);
+       if (!opp_table) {
+               ret = -ENOMEM;
+               goto unlock;
+       }
+
+       ret = _opp_add_v1(opp_table, dev, freq, u_volt, true);
+       if (ret)
+               _remove_opp_table(opp_table);
+
+unlock:
+       mutex_unlock(&opp_table_lock);
+       return ret;
 }
 EXPORT_SYMBOL_GPL(dev_pm_opp_add);
 
@@ -1888,8 +1889,8 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_notifier);
  * Free OPPs either created using static entries present in DT or even the
  * dynamically added entries based on remove_all param.
  */
-static void _dev_pm_opp_remove_table(struct opp_table *opp_table,
-                                    struct device *dev, bool remove_all)
+void _dev_pm_opp_remove_table(struct opp_table *opp_table, struct device *dev,
+                             bool remove_all)
 {
        struct dev_pm_opp *opp, *tmp;
 

diff --git a/drivers/base/power/opp/of.c b/drivers/base/power/opp/of.c
index 442fa46..cdbf733 100644 (file)
--- a/drivers/base/power/opp/of.c
+++ b/drivers/base/power/opp/of.c
@@ -255,6 +255,7 @@ static struct device_node *_of_get_opp_desc_node(struct device *dev)
 
 /**
  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
+ * @opp_table: OPP table
  * @dev:       device for which we do this operation
  * @np:                device node
  *
@@ -276,22 +277,17 @@ static struct device_node *_of_get_opp_desc_node(struct device *dev)
  * -ENOMEM     Memory allocation failure
  * -EINVAL     Failed parsing the OPP node
  */
-static int _opp_add_static_v2(struct device *dev, struct device_node *np)
+static int _opp_add_static_v2(struct opp_table *opp_table, struct device *dev,
+                             struct device_node *np)
 {
-       struct opp_table *opp_table;
        struct dev_pm_opp *new_opp;
        u64 rate;
        u32 val;
        int ret;
 
-       /* Hold our table modification lock here */
-       mutex_lock(&opp_table_lock);
-
-       new_opp = _opp_allocate(dev, &opp_table);
-       if (!new_opp) {
-               ret = -ENOMEM;
-               goto unlock;
-       }
+       new_opp = _opp_allocate(opp_table);
+       if (!new_opp)
+               return -ENOMEM;
 
        ret = of_property_read_u64(np, "opp-hz", &rate);
        if (ret < 0) {
@@ -347,8 +343,6 @@ static int _opp_add_static_v2(struct device *dev, struct device_node *np)
        if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
                opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 
-       mutex_unlock(&opp_table_lock);
-
        pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
                 __func__, new_opp->turbo, new_opp->rate,
                 new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
@@ -362,9 +356,8 @@ static int _opp_add_static_v2(struct device *dev, struct device_node *np)
        return 0;
 
 free_opp:
-       _opp_free(new_opp, opp_table);
-unlock:
-       mutex_unlock(&opp_table_lock);
+       _opp_free(new_opp);
+
        return ret;
 }
 
@@ -382,16 +375,20 @@ static int _of_add_opp_table_v2(struct device *dev, struct device_node *opp_np)
                /* OPPs are already managed */
                if (!_add_opp_dev(dev, opp_table))
                        ret = -ENOMEM;
-               mutex_unlock(&opp_table_lock);
-               return ret;
+               goto unlock;
+       }
+
+       opp_table = _add_opp_table(dev);
+       if (!opp_table) {
+               ret = -ENOMEM;
+               goto unlock;
        }
-       mutex_unlock(&opp_table_lock);
 
        /* We have opp-table node now, iterate over it and add OPPs */
        for_each_available_child_of_node(opp_np, np) {
                count++;
 
-               ret = _opp_add_static_v2(dev, np);
+               ret = _opp_add_static_v2(opp_table, dev, np);
                if (ret) {
                        dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
                                ret);
@@ -400,15 +397,8 @@ static int _of_add_opp_table_v2(struct device *dev, struct device_node *opp_np)
        }
 
        /* There should be one of more OPP defined */
-       if (WARN_ON(!count))
-               return -ENOENT;
-
-       mutex_lock(&opp_table_lock);
-
-       opp_table = _find_opp_table(dev);
-       if (WARN_ON(IS_ERR(opp_table))) {
-               ret = PTR_ERR(opp_table);
-               mutex_unlock(&opp_table_lock);
+       if (WARN_ON(!count)) {
+               ret = -ENOENT;
                goto free_table;
        }
 
@@ -418,12 +408,12 @@ static int _of_add_opp_table_v2(struct device *dev, struct device_node *opp_np)
        else
                opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 
-       mutex_unlock(&opp_table_lock);
-
-       return 0;
+       goto unlock;
 
 free_table:
-       dev_pm_opp_of_remove_table(dev);
+       _dev_pm_opp_remove_table(opp_table, dev, false);
+unlock:
+       mutex_unlock(&opp_table_lock);
 
        return ret;
 }
@@ -431,9 +421,10 @@ free_table:
 /* Initializes OPP tables based on old-deprecated bindings */
 static int _of_add_opp_table_v1(struct device *dev)
 {
+       struct opp_table *opp_table;
        const struct property *prop;
        const __be32 *val;
-       int nr, ret;
+       int nr, ret = 0;
 
        prop = of_find_property(dev->of_node, "operating-points", NULL);
        if (!prop)
@@ -451,22 +442,32 @@ static int _of_add_opp_table_v1(struct device *dev)
                return -EINVAL;
        }
 
+       mutex_lock(&opp_table_lock);
+
+       opp_table = _add_opp_table(dev);
+       if (!opp_table) {
+               ret = -ENOMEM;
+               goto unlock;
+       }
+
        val = prop->value;
        while (nr) {
                unsigned long freq = be32_to_cpup(val++) * 1000;
                unsigned long volt = be32_to_cpup(val++);
 
-               ret = _opp_add_v1(dev, freq, volt, false);
+               ret = _opp_add_v1(opp_table, dev, freq, volt, false);
                if (ret) {
                        dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
                                __func__, freq, ret);
-                       dev_pm_opp_of_remove_table(dev);
-                       return ret;
+                       _dev_pm_opp_remove_table(opp_table, dev, false);
+                       break;
                }
                nr -= 2;
        }
 
-       return 0;
+unlock:
+       mutex_unlock(&opp_table_lock);
+       return ret;
 }
 
 /**

diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h
index c4b539a..0a5eb4d 100644 (file)
--- a/drivers/base/power/opp/opp.h
+++ b/drivers/base/power/opp/opp.h
@@ -191,13 +191,16 @@ struct opp_table {
 
 /* Routines internal to opp core */
 struct opp_table *_find_opp_table(struct device *dev);
+struct opp_table *_add_opp_table(struct device *dev);
 struct opp_device *_add_opp_dev(const struct device *dev, struct opp_table *opp_table);
+void _dev_pm_opp_remove_table(struct opp_table *opp_table, struct device *dev, bool remove_all);
 void _dev_pm_opp_find_and_remove_table(struct device *dev, bool remove_all);
-struct dev_pm_opp *_opp_allocate(struct device *dev, struct opp_table **opp_table);
-void _opp_free(struct dev_pm_opp *opp, struct opp_table *opp_table);
+struct dev_pm_opp *_opp_allocate(struct opp_table *opp_table);
+void _opp_free(struct dev_pm_opp *opp);
 int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, struct opp_table *opp_table);
-int _opp_add_v1(struct device *dev, unsigned long freq, long u_volt, bool dynamic);
+int _opp_add_v1(struct opp_table *opp_table, struct device *dev, unsigned long freq, long u_volt, bool dynamic);
 void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask, bool of);
+struct opp_table *_add_opp_table(struct device *dev);
 
 #ifdef CONFIG_OF
 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev);