[PATCH V2 3/6] PM / QOS: Add 'performance' request

Viresh Kumar
2017-02-09T03:41:49Z

Add a new QOS request type: DEV_PM_QOS_PERFORMANCE.

This is required to support runtime performance constraints for the
devices. Also allow notifiers to be registered against it, which can be
used by frameworks like genpd.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
Documentation/power/pm_qos_interface.txt | 2 +-
drivers/base/power/qos.c | 69 +++++++++++++++++++++++++++-----
include/linux/pm_qos.h | 4 ++
3 files changed, 63 insertions(+), 12 deletions(-)

diff --git a/Documentation/power/pm_qos_interface.txt b/Documentation/power/pm_qos_interface.txt
index c7989d140428..a0a45ecbc1a8 100644
--- a/Documentation/power/pm_qos_interface.txt
+++ b/Documentation/power/pm_qos_interface.txt
@@ -172,7 +172,7 @@ type.

The callback is called when the aggregated value of the device constraints list
is changed. Currently it only supports the notifier to be registered for resume
-latency device PM QoS.
+latency and performance device PM QoS.

int dev_pm_qos_remove_notifier(device, notifier, type):
Removes the notification callback function for the device.
diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c
index 9adc208cf1fc..cf070468a7ca 100644
--- a/drivers/base/power/qos.c
+++ b/drivers/base/power/qos.c
@@ -163,6 +163,10 @@ static int apply_constraint(struct dev_pm_qos_request *req,
req->dev->power.set_latency_tolerance(req->dev, value);
}
break;
+ case DEV_PM_QOS_PERFORMANCE:
+ ret = pm_qos_update_target(&qos->performance, &req->data.pnode,
+ action, value);
+ break;
case DEV_PM_QOS_FLAGS:
ret = pm_qos_update_flags(&qos->flags, &req->data.flr,
action, value);
@@ -191,12 +195,13 @@ static int dev_pm_qos_constraints_allocate(struct device *dev)
if (!qos)
return -ENOMEM;

- n = kzalloc(sizeof(*n), GFP_KERNEL);
+ n = kzalloc(2 * sizeof(*n), GFP_KERNEL);
if (!n) {
kfree(qos);
return -ENOMEM;
}
BLOCKING_INIT_NOTIFIER_HEAD(n);
+ BLOCKING_INIT_NOTIFIER_HEAD(n + 1);

c = &qos->resume_latency;
plist_head_init(&c->list);
@@ -213,6 +218,14 @@ static int dev_pm_qos_constraints_allocate(struct device *dev)
c->no_constraint_value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT;
c->type = PM_QOS_MIN;

+ c = &qos->performance;
+ plist_head_init(&c->list);
+ c->target_value = PM_QOS_PERFORMANCE_DEFAULT_VALUE;
+ c->default_value = PM_QOS_PERFORMANCE_DEFAULT_VALUE;
+ c->no_constraint_value = PM_QOS_PERFORMANCE_DEFAULT_VALUE;
+ c->type = PM_QOS_MAX;
+ c->notifiers = n + 1;
+
INIT_LIST_HEAD(&qos->flags.list);

spin_lock_irq(&dev->power.lock);
@@ -271,6 +284,11 @@ void dev_pm_qos_constraints_destroy(struct device *dev)
apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE);
memset(req, 0, sizeof(*req));
}
+ c = &qos->performance;
+ plist_for_each_entry_safe(req, tmp, &c->list, data.pnode) {
+ apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE);
+ memset(req, 0, sizeof(*req));
+ }
f = &qos->flags;
list_for_each_entry_safe(req, tmp, &f->list, data.flr.node) {
apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE);
@@ -382,6 +400,7 @@ 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:
+ case DEV_PM_QOS_PERFORMANCE:
curr_value = req->data.pnode.prio;
break;
case DEV_PM_QOS_FLAGS:
@@ -492,11 +511,9 @@ EXPORT_SYMBOL_GPL(dev_pm_qos_remove_request);
int dev_pm_qos_add_notifier(struct device *dev, struct notifier_block *notifier,
enum dev_pm_qos_req_type type)
{
+ struct dev_pm_qos *qos;
int ret = 0;

- if (WARN_ON(type != DEV_PM_QOS_RESUME_LATENCY))
- return -EINVAL;
-
mutex_lock(&dev_pm_qos_mtx);

if (IS_ERR(dev->power.qos))
@@ -504,10 +521,26 @@ int dev_pm_qos_add_notifier(struct device *dev, struct notifier_block *notifier,
else if (!dev->power.qos)
ret = dev_pm_qos_constraints_allocate(dev);

- if (!ret)
- ret = blocking_notifier_chain_register(dev->power.qos->resume_latency.notifiers,
+ if (ret)
+ goto unlock;
+
+ qos = dev->power.qos;
+
+ switch (type) {
+ case DEV_PM_QOS_RESUME_LATENCY:
+ ret = blocking_notifier_chain_register(qos->resume_latency.notifiers,
+ notifier);
+ break;
+ case DEV_PM_QOS_PERFORMANCE:
+ ret = blocking_notifier_chain_register(qos->performance.notifiers,
notifier);
+ break;
+ default:
+ WARN_ON(1);
+ ret = -EINVAL;
+ }

+unlock:
mutex_unlock(&dev_pm_qos_mtx);
return ret;
}
@@ -528,18 +561,32 @@ int dev_pm_qos_remove_notifier(struct device *dev,
struct notifier_block *notifier,
enum dev_pm_qos_req_type type)
{
+ struct dev_pm_qos *qos;
int retval = 0;

- if (WARN_ON(type != DEV_PM_QOS_RESUME_LATENCY))
- return -EINVAL;
-
mutex_lock(&dev_pm_qos_mtx);

+ qos = dev->power.qos;
+
/* Silently return if the constraints object is not present. */
- if (!IS_ERR_OR_NULL(dev->power.qos))
- retval = blocking_notifier_chain_unregister(dev->power.qos->resume_latency.notifiers,
+ if (IS_ERR_OR_NULL(qos))
+ goto unlock;
+
+ switch (type) {
+ case DEV_PM_QOS_RESUME_LATENCY:
+ retval = blocking_notifier_chain_unregister(qos->resume_latency.notifiers,
+ notifier);
+ break;
+ case DEV_PM_QOS_PERFORMANCE:
+ retval = blocking_notifier_chain_unregister(qos->performance.notifiers,
notifier);
+ break;
+ default:
+ WARN_ON(1);
+ retval = -EINVAL;
+ }

+unlock:
mutex_unlock(&dev_pm_qos_mtx);
return retval;
}
diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index 08cfaeb6c178..0e8386adb21c 100644
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -36,6 +36,7 @@ enum pm_qos_flags_status {
#define PM_QOS_RESUME_LATENCY_DEFAULT_VALUE 0
#define PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE 0
#define PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT (-1)
+#define PM_QOS_PERFORMANCE_DEFAULT_VALUE 0
#define PM_QOS_LATENCY_ANY ((s32)(~(__u32)0 >> 1))

#define PM_QOS_FLAG_NO_POWER_OFF (1 << 0)
@@ -55,6 +56,7 @@ struct pm_qos_flags_request {
enum dev_pm_qos_req_type {
DEV_PM_QOS_RESUME_LATENCY = 1,
DEV_PM_QOS_LATENCY_TOLERANCE,
+ DEV_PM_QOS_PERFORMANCE,
DEV_PM_QOS_FLAGS,
};

@@ -96,9 +98,11 @@ struct pm_qos_flags {
struct dev_pm_qos {
struct pm_qos_constraints resume_latency;
struct pm_qos_constraints latency_tolerance;
+ struct pm_qos_constraints performance;
struct pm_qos_flags flags;
struct dev_pm_qos_request *resume_latency_req;
struct dev_pm_qos_request *latency_tolerance_req;
+ struct dev_pm_qos_request *performance_req;
struct dev_pm_qos_request *flags_req;
};

--
2.7.1.410.g6faf27b