[PATCH v3 1/4] QoS: Modify data structures and function arguments for scalability.

Lina Iyer
2014-08-27T20:15:42Z

From: Praveen Chidambaram <pchidamb@codeaurora.org>

QoS add requests uses a handle to the priority list that is used
internally to save the request, but this does not extend well. Also,
dev_pm_qos structure definition seems to use a list object directly.
The 'derivative' relationship seems to be broken.

Use pm_qos_request objects instead of passing around the protected
priority list object.

Signed-off-by: Praveen Chidambaram <pchidamb@codeaurora.org>
Signed-off-by: Lina Iyer <lina.iyer@linaro.org>

diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c
index 36b9eb4..67a66b1 100644
--- a/drivers/base/power/qos.c
+++ b/drivers/base/power/qos.c
@@ -143,7 +143,7 @@ static int apply_constraint(struct dev_pm_qos_request *req,
switch(req->type) {
case DEV_PM_QOS_RESUME_LATENCY:
ret = pm_qos_update_target(&qos->resume_latency,
- &req->data.pnode, action, value);
+ &req->data.lat, action, value);
if (ret) {
value = pm_qos_read_value(&qos->resume_latency);
blocking_notifier_call_chain(&dev_pm_notifiers,
@@ -153,7 +153,7 @@ static int apply_constraint(struct dev_pm_qos_request *req,
break;
case DEV_PM_QOS_LATENCY_TOLERANCE:
ret = pm_qos_update_target(&qos->latency_tolerance,
- &req->data.pnode, action, value);
+ &req->data.lat, action, value);
if (ret) {
value = pm_qos_read_value(&qos->latency_tolerance);
req->dev->power.set_latency_tolerance(req->dev, value);
@@ -254,7 +254,7 @@ void dev_pm_qos_constraints_destroy(struct device *dev)

/* Flush the constraints lists for the device. */
c = &qos->resume_latency;
- plist_for_each_entry_safe(req, tmp, &c->list, data.pnode) {
+ plist_for_each_entry_safe(req, tmp, &c->list, data.lat.node) {
/*
* Update constraints list and call the notification
* callbacks if needed
@@ -263,7 +263,7 @@ void dev_pm_qos_constraints_destroy(struct device *dev)
memset(req, 0, sizeof(*req));
}
c = &qos->latency_tolerance;
- plist_for_each_entry_safe(req, tmp, &c->list, data.pnode) {
+ plist_for_each_entry_safe(req, tmp, &c->list, data.lat.node) {
apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE);
memset(req, 0, sizeof(*req));
}
@@ -378,7 +378,7 @@ static int __dev_pm_qos_update_request(struct dev_pm_qos_request *req,
switch(req->type) {
case DEV_PM_QOS_RESUME_LATENCY:
case DEV_PM_QOS_LATENCY_TOLERANCE:
- curr_value = req->data.pnode.prio;
+ curr_value = req->data.lat.node.prio;
break;
case DEV_PM_QOS_FLAGS:
curr_value = req->data.flr.flags;
@@ -831,8 +831,8 @@ s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev)
mutex_lock(&dev_pm_qos_mtx);
ret = IS_ERR_OR_NULL(dev->power.qos)
|| !dev->power.qos->latency_tolerance_req ?
- PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT :
- dev->power.qos->latency_tolerance_req->data.pnode.prio;
+ PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT :
+ dev->power.qos->latency_tolerance_req->data.lat.node.prio;
mutex_unlock(&dev_pm_qos_mtx);
return ret;
}
diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index 9ab4bf7..e1b763d 100644
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -60,7 +60,7 @@ enum dev_pm_qos_req_type {
struct dev_pm_qos_request {
enum dev_pm_qos_req_type type;
union {
- struct plist_node pnode;
+ struct pm_qos_request lat;
struct pm_qos_flags_request flr;
} data;
struct device *dev;
@@ -112,7 +112,8 @@ static inline int dev_pm_qos_request_active(struct dev_pm_qos_request *req)
return req->dev != NULL;
}

-int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
+int pm_qos_update_target(struct pm_qos_constraints *c,
+ struct pm_qos_request *req,
enum pm_qos_req_action action, int value);
bool pm_qos_update_flags(struct pm_qos_flags *pqf,
struct pm_qos_flags_request *req,
@@ -210,7 +211,7 @@ int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val);

static inline s32 dev_pm_qos_requested_resume_latency(struct device *dev)
{
- return dev->power.qos->resume_latency_req->data.pnode.prio;
+ return dev->power.qos->resume_latency_req->data.lat.node.prio;
}

static inline s32 dev_pm_qos_requested_flags(struct device *dev)
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index 884b770..d0b9c0f 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -161,19 +161,21 @@ static inline void pm_qos_set_value(struct pm_qos_constraints *c, s32 value)
* pm_qos_update_target - manages the constraints list and calls the notifiers
* if needed
* @c: constraints data struct
- * @node: request to add to the list, to update or to remove
+ * @req: request to add to the list, to update or to remove
* @action: action to take on the constraints list
* @value: value of the request to add or update
*
* This function returns 1 if the aggregated constraint value has changed, 0
* otherwise.
*/
-int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
+int pm_qos_update_target(struct pm_qos_constraints *c,
+ struct pm_qos_request *req,
enum pm_qos_req_action action, int value)
{
unsigned long flags;
int prev_value, curr_value, new_value;
int ret;
+ struct plist_node *node = &req->node;

spin_lock_irqsave(&pm_qos_lock, flags);
prev_value = pm_qos_get_value(c);
@@ -310,7 +312,7 @@ static void __pm_qos_update_request(struct pm_qos_request *req,
if (new_value != req->node.prio)
pm_qos_update_target(
pm_qos_array[req->pm_qos_class]->constraints,
- &req->node, PM_QOS_UPDATE_REQ, new_value);
+ req, PM_QOS_UPDATE_REQ, new_value);
}

/**
@@ -355,7 +357,7 @@ void pm_qos_add_request(struct pm_qos_request *req,
INIT_DELAYED_WORK(&req->work, pm_qos_work_fn);
trace_pm_qos_add_request(pm_qos_class, value);
pm_qos_update_target(pm_qos_array[pm_qos_class]->constraints,
- &req->node, PM_QOS_ADD_REQ, value);
+ req, PM_QOS_ADD_REQ, value);
}
EXPORT_SYMBOL_GPL(pm_qos_add_request);

@@ -409,7 +411,7 @@ void pm_qos_update_request_timeout(struct pm_qos_request *req, s32 new_value,
if (new_value != req->node.prio)
pm_qos_update_target(
pm_qos_array[req->pm_qos_class]->constraints,
- &req->node, PM_QOS_UPDATE_REQ, new_value);
+ req, PM_QOS_UPDATE_REQ, new_value);

schedule_delayed_work(&req->work, usecs_to_jiffies(timeout_us));
}
@@ -437,7 +439,7 @@ void pm_qos_remove_request(struct pm_qos_request *req)

trace_pm_qos_remove_request(req->pm_qos_class, PM_QOS_DEFAULT_VALUE);
pm_qos_update_target(pm_qos_array[req->pm_qos_class]->constraints,
- &req->node, PM_QOS_REMOVE_REQ,
+ req, PM_QOS_REMOVE_REQ,
PM_QOS_DEFAULT_VALUE);
memset(req, 0, sizeof(*req));
}
--
1.9.1