[PATCH 04/15] PM QoS: re-organize data structs

[jean.pihet@newoldbits.com]

From: Jean Pihet <j-pihet@ti.com>

In preparation for the per-device constratins support, re-organize
the data strctures:
- add a struct pm_qos_constraints which contains the constraints
related data
- update struct pm_qos_object contents to the PM QoS internal object
data. Add a pointer to struct pm_qos_constraints
- update the internal code to use the new data structs.

Signed-off-by: Jean Pihet <j-pihet@ti.com>
---
 include/linux/pm_qos.h |   19 +++++++++++
 kernel/power/qos.c     |   85 +++++++++++++++++++++++-------------------------
 2 files changed, 60 insertions(+), 44 deletions(-)

diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index 6b0968f..9772311 100644
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -25,6 +25,25 @@ struct pm_qos_request {
 	int pm_qos_class;
 };
 
+enum pm_qos_type {
+	PM_QOS_UNITIALIZED,
+	PM_QOS_MAX,		/* return the largest value */
+	PM_QOS_MIN		/* return the smallest value */
+};
+
+/*
+ * Note: The lockless read path depends on the CPU accessing
+ * target_value atomically.  Atomic access is only guaranteed on all CPU
+ * types linux supports for 32 bit quantites
+ */
+struct pm_qos_constraints {
+	struct plist_head list;
+	s32 target_value;	/* Do not change to 64 bit */
+	s32 default_value;
+	enum pm_qos_type type;
+	struct blocking_notifier_head *notifiers;
+};
+
 #ifdef CONFIG_PM
 void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class,
 			s32 value);
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index 788c4cf..4a35fe5 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -49,58 +49,53 @@
  * or pm_qos_object list and pm_qos_objects need to happen with pm_qos_lock
  * held, taken with _irqsave.  One lock to rule them all
  */
-enum pm_qos_type {
-	PM_QOS_MAX,		/* return the largest value */
-	PM_QOS_MIN		/* return the smallest value */
-};
-
-/*
- * Note: The lockless read path depends on the CPU accessing
- * target_value atomically.  Atomic access is only guaranteed on all CPU
- * types linux supports for 32 bit quantites
- */
 struct pm_qos_object {
-	struct plist_head constraints;
-	struct blocking_notifier_head *notifiers;
+	struct pm_qos_constraints *constraints;
 	struct miscdevice pm_qos_power_miscdev;
 	char *name;
-	s32 target_value;	/* Do not change to 64 bit */
-	s32 default_value;
-	enum pm_qos_type type;
 };
 
 static DEFINE_SPINLOCK(pm_qos_lock);
 
 static struct pm_qos_object null_pm_qos;
+
 static BLOCKING_NOTIFIER_HEAD(cpu_dma_lat_notifier);
-static struct pm_qos_object cpu_dma_pm_qos = {
-	.constraints = PLIST_HEAD_INIT(cpu_dma_pm_qos.constraints),
-	.notifiers = &cpu_dma_lat_notifier,
-	.name = "cpu_dma_latency",
+static struct pm_qos_constraints cpu_dma_constraints = {
+	.list = PLIST_HEAD_INIT(cpu_dma_constraints.list),
 	.target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
 	.default_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
 	.type = PM_QOS_MIN,
+	.notifiers = &cpu_dma_lat_notifier,
+};
+static struct pm_qos_object cpu_dma_pm_qos = {
+	.constraints = &cpu_dma_constraints,
 };
 
 static BLOCKING_NOTIFIER_HEAD(network_lat_notifier);
-static struct pm_qos_object network_lat_pm_qos = {
-	.constraints = PLIST_HEAD_INIT(network_lat_pm_qos.constraints),
-	.notifiers = &network_lat_notifier,
-	.name = "network_latency",
+static struct pm_qos_constraints network_lat_constraints = {
+	.list = PLIST_HEAD_INIT(network_lat_constraints.list),
 	.target_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE,
 	.default_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE,
-	.type = PM_QOS_MIN
+	.type = PM_QOS_MIN,
+	.notifiers = &network_lat_notifier,
+};
+static struct pm_qos_object network_lat_pm_qos = {
+	.constraints = &network_lat_constraints,
+	.name = "network_latency",
 };
 
 
 static BLOCKING_NOTIFIER_HEAD(network_throughput_notifier);
-static struct pm_qos_object network_throughput_pm_qos = {
-	.constraints = PLIST_HEAD_INIT(network_throughput_pm_qos.constraints),
-	.notifiers = &network_throughput_notifier,
-	.name = "network_throughput",
+static struct pm_qos_constraints network_tput_constraints = {
+	.list = PLIST_HEAD_INIT(network_tput_constraints.list),
 	.target_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE,
 	.default_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE,
 	.type = PM_QOS_MAX,
+	.notifiers = &network_throughput_notifier,
+};
+static struct pm_qos_object network_throughput_pm_qos = {
+	.constraints = &network_tput_constraints,
+	.name = "network_throughput",
 };
 
 
@@ -129,15 +124,15 @@ static const struct file_operations pm_qos_power_fops = {
 /* unlocked internal variant */
 static inline int pm_qos_get_value(struct pm_qos_object *o)
 {
-	if (plist_head_empty(&o->constraints))
-		return o->default_value;
+	if (plist_head_empty(&o->constraints->list))
+		return o->constraints->default_value;
 
-	switch (o->type) {
+	switch (o->constraints->type) {
 	case PM_QOS_MIN:
-		return plist_first(&o->constraints)->prio;
+		return plist_first(&o->constraints->list)->prio;
 
 	case PM_QOS_MAX:
-		return plist_last(&o->constraints)->prio;
+		return plist_last(&o->constraints->list)->prio;
 
 	default:
 		/* runtime check for not using enum */
@@ -147,12 +142,12 @@ static inline int pm_qos_get_value(struct pm_qos_object *o)
 
 static inline s32 pm_qos_read_value(struct pm_qos_object *o)
 {
-	return o->target_value;
+	return o->constraints->target_value;
 }
 
 static inline void pm_qos_set_value(struct pm_qos_object *o, s32 value)
 {
-	o->target_value = value;
+	o->constraints->target_value = value;
 }
 
 static void update_target(struct pm_qos_object *o, struct plist_node *node,
@@ -170,20 +165,20 @@ static void update_target(struct pm_qos_object *o, struct plist_node *node,
 		 * with new value and add, then see if the extremal
 		 * changed
 		 */
-		plist_del(node, &o->constraints);
+		plist_del(node, &o->constraints->list);
 		plist_node_init(node, value);
-		plist_add(node, &o->constraints);
+		plist_add(node, &o->constraints->list);
 	} else if (del) {
-		plist_del(node, &o->constraints);
+		plist_del(node, &o->constraints->list);
 	} else {
-		plist_add(node, &o->constraints);
+		plist_add(node, &o->constraints->list);
 	}
 	curr_value = pm_qos_get_value(o);
 	pm_qos_set_value(o, curr_value);
 	spin_unlock_irqrestore(&pm_qos_lock, flags);
 
 	if (prev_value != curr_value)
-		blocking_notifier_call_chain(o->notifiers,
+		blocking_notifier_call_chain(o->constraints->notifiers,
 					     (unsigned long)curr_value,
 					     NULL);
 }
@@ -230,7 +225,7 @@ void pm_qos_add_request(struct pm_qos_request *req,
 		return;
 	}
 	if (value == PM_QOS_DEFAULT_VALUE)
-		new_value = o->default_value;
+		new_value = o->constraints->default_value;
 	else
 		new_value = value;
 	plist_node_init(&req->node, new_value);
@@ -266,7 +261,7 @@ void pm_qos_update_request(struct pm_qos_request *req,
 	o = pm_qos_array[req->pm_qos_class];
 
 	if (new_value == PM_QOS_DEFAULT_VALUE)
-		temp = o->default_value;
+		temp = o->constraints->default_value;
 	else
 		temp = new_value;
 
@@ -315,7 +310,8 @@ int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier)
 	int retval;
 
 	retval = blocking_notifier_chain_register(
-			pm_qos_array[pm_qos_class]->notifiers, notifier);
+			pm_qos_array[pm_qos_class]->constraints->notifiers,
+			notifier);
 
 	return retval;
 }
@@ -334,7 +330,8 @@ int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier)
 	int retval;
 
 	retval = blocking_notifier_chain_unregister(
-			pm_qos_array[pm_qos_class]->notifiers, notifier);
+			pm_qos_array[pm_qos_class]->constraints->notifiers,
+			notifier);
 
 	return retval;
 }
-- 
1.7.4.1