Later commits would add support for new OPP bindings and this would be required then. So, lets do it in a separate patch to make it easily reviewable.
Another change worth noticing is INIT_LIST_HEAD(&opp->node). We weren't doing it earlier as we never tried to delete a list node before it is added to list. But this wouldn't be the case anymore. We might try to delete a node (just to reuse the same code paths), without it being getting added to the list.
Reviewed-by: Bartlomiej Zolnierkiewicz b.zolnierkie@samsung.com Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/base/power/opp.c | 125 ++++++++++++++++++++++++++++------------------- 1 file changed, 76 insertions(+), 49 deletions(-)
diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index 28d70c9f86ed..0d8dbf21c299 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -484,6 +484,7 @@ static void _kfree_opp_rcu(struct rcu_head *head) * _opp_remove() - Remove an OPP from a table definition * @dev_opp: points back to the device_opp struct this opp belongs to * @opp: pointer to the OPP to remove + * @notify: OPP_EVENT_REMOVE notification should be sent or not * * This function removes an opp definition from the opp list. * @@ -492,13 +493,14 @@ static void _kfree_opp_rcu(struct rcu_head *head) * strategy. */ static void _opp_remove(struct device_opp *dev_opp, - struct dev_pm_opp *opp) + struct dev_pm_opp *opp, bool notify) { /* * Notify the changes in the availability of the operable * frequency/voltage list. */ - srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_REMOVE, opp); + if (notify) + srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_REMOVE, opp); list_del_rcu(&opp->node); call_srcu(&dev_opp->srcu_head.srcu, &opp->rcu_head, _kfree_opp_rcu);
@@ -544,12 +546,70 @@ void dev_pm_opp_remove(struct device *dev, unsigned long freq) goto unlock; }
- _opp_remove(dev_opp, opp); + _opp_remove(dev_opp, opp, true); unlock: mutex_unlock(&dev_opp_list_lock); } EXPORT_SYMBOL_GPL(dev_pm_opp_remove);
+static struct dev_pm_opp *_allocate_opp(struct device *dev, + struct device_opp **dev_opp) +{ + struct dev_pm_opp *opp; + + /* allocate new OPP node */ + opp = kzalloc(sizeof(*opp), GFP_KERNEL); + if (!opp) + return NULL; + + INIT_LIST_HEAD(&opp->node); + + *dev_opp = _add_device_opp(dev); + if (!*dev_opp) { + kfree(opp); + return NULL; + } + + return opp; +} + +static int _opp_add(struct dev_pm_opp *new_opp, struct device_opp *dev_opp) +{ + struct dev_pm_opp *opp; + struct list_head *head = &dev_opp->opp_list; + + /* + * Insert new OPP in order of increasing frequency and discard if + * already present. + * + * Need to use &dev_opp->opp_list in the condition part of the 'for' + * loop, don't replace it with head otherwise it will become an infinite + * loop. + */ + list_for_each_entry_rcu(opp, &dev_opp->opp_list, node) { + if (new_opp->rate > opp->rate) { + head = &opp->node; + continue; + } + + if (new_opp->rate < opp->rate) + break; + + /* Duplicate OPPs */ + dev_warn(dev_opp->dev, "%s: duplicate OPPs detected. Existing: freq: %lu, volt: %lu, enabled: %d. New: freq: %lu, volt: %lu, enabled: %d\n", + __func__, opp->rate, opp->u_volt, opp->available, + new_opp->rate, new_opp->u_volt, new_opp->available); + + return opp->available && new_opp->u_volt == opp->u_volt ? + 0 : -EEXIST; + } + + new_opp->dev_opp = dev_opp; + list_add_rcu(&new_opp->node, head); + + return 0; +} + /** * _opp_add_dynamic() - Allocate a dynamic OPP. * @dev: device for which we do this operation @@ -581,62 +641,28 @@ static int _opp_add_dynamic(struct device *dev, unsigned long freq, long u_volt, bool dynamic) { struct device_opp *dev_opp; - struct dev_pm_opp *opp, *new_opp; - struct list_head *head; + struct dev_pm_opp *new_opp; int ret;
- /* allocate new OPP node */ - new_opp = kzalloc(sizeof(*new_opp), GFP_KERNEL); - if (!new_opp) - return -ENOMEM; - /* Hold our list modification lock here */ mutex_lock(&dev_opp_list_lock);
+ new_opp = _allocate_opp(dev, &dev_opp); + if (!new_opp) { + ret = -ENOMEM; + goto unlock; + } + /* populate the opp table */ new_opp->rate = freq; new_opp->u_volt = u_volt; new_opp->available = true; + new_opp->dynamic = dynamic;
- dev_opp = _add_device_opp(dev); - if (!dev_opp) { - ret = -ENOMEM; - goto free_opp; - } - - /* - * Insert new OPP in order of increasing frequency - * and discard if already present - */ - head = &dev_opp->opp_list; - - /* - * Need to use &dev_opp->opp_list in the condition part of the 'for' - * loop, don't replace it with head otherwise it will become an infinite - * loop. - */ - list_for_each_entry_rcu(opp, &dev_opp->opp_list, node) { - if (new_opp->rate > opp->rate) { - head = &opp->node; - continue; - } - - if (new_opp->rate < opp->rate) - break; - - /* Duplicate OPPs */ - ret = opp->available && new_opp->u_volt == opp->u_volt ? - 0 : -EEXIST; - - dev_warn(dev, "%s: duplicate OPPs detected. Existing: freq: %lu, volt: %lu, enabled: %d. New: freq: %lu, volt: %lu, enabled: %d\n", - __func__, opp->rate, opp->u_volt, opp->available, - new_opp->rate, new_opp->u_volt, new_opp->available); + ret = _opp_add(new_opp, dev_opp); + if (ret) goto free_opp; - }
- new_opp->dynamic = dynamic; - new_opp->dev_opp = dev_opp; - list_add_rcu(&new_opp->node, head); mutex_unlock(&dev_opp_list_lock);
/* @@ -647,8 +673,9 @@ static int _opp_add_dynamic(struct device *dev, unsigned long freq, return 0;
free_opp: + _opp_remove(dev_opp, new_opp, false); +unlock: mutex_unlock(&dev_opp_list_lock); - kfree(new_opp); return ret; }
@@ -876,7 +903,7 @@ void of_free_opp_table(struct device *dev) /* Free static OPPs */ list_for_each_entry_safe(opp, tmp, &dev_opp->opp_list, node) { if (!opp->dynamic) - _opp_remove(dev_opp, opp); + _opp_remove(dev_opp, opp, true); }
mutex_unlock(&dev_opp_list_lock);