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yaml
---
r: 305826
b: refs/heads/master
c: 6ff7bb0
h: refs/heads/master
v: v3
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Rafael J. Wysocki committed May 5, 2012
1 parent 2a932b6 commit 2868d7a
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Showing 4 changed files with 154 additions and 20 deletions.
2 changes: 1 addition & 1 deletion [refs]
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Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: efa6902501ffc87d69bfb10b8a09b7d6ee222d77
refs/heads/master: 6ff7bb0d02f82968be13937c03e93b6c090229df
120 changes: 104 additions & 16 deletions trunk/drivers/base/power/domain.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -11,6 +11,7 @@
#include <linux/io.h>
#include <linux/pm_runtime.h>
#include <linux/pm_domain.h>
#include <linux/pm_qos.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/sched.h>
Expand Down Expand Up @@ -38,11 +39,13 @@
ktime_t __start = ktime_get(); \
type __retval = GENPD_DEV_CALLBACK(genpd, type, callback, dev); \
s64 __elapsed = ktime_to_ns(ktime_sub(ktime_get(), __start)); \
struct generic_pm_domain_data *__gpd_data = dev_gpd_data(dev); \
if (__elapsed > __gpd_data->td.field) { \
__gpd_data->td.field = __elapsed; \
struct gpd_timing_data *__td = &dev_gpd_data(dev)->td; \
if (!__retval && __elapsed > __td->field) { \
__td->field = __elapsed; \
dev_warn(dev, name " latency exceeded, new value %lld ns\n", \
__elapsed); \
genpd->max_off_time_changed = true; \
__td->constraint_changed = true; \
} \
__retval; \
})
Expand Down Expand Up @@ -211,6 +214,7 @@ int __pm_genpd_poweron(struct generic_pm_domain *genpd)
elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
if (elapsed_ns > genpd->power_on_latency_ns) {
genpd->power_on_latency_ns = elapsed_ns;
genpd->max_off_time_changed = true;
if (genpd->name)
pr_warning("%s: Power-on latency exceeded, "
"new value %lld ns\n", genpd->name,
Expand Down Expand Up @@ -247,6 +251,53 @@ int pm_genpd_poweron(struct generic_pm_domain *genpd)

#ifdef CONFIG_PM_RUNTIME

static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
unsigned long val, void *ptr)
{
struct generic_pm_domain_data *gpd_data;
struct device *dev;

gpd_data = container_of(nb, struct generic_pm_domain_data, nb);

mutex_lock(&gpd_data->lock);
dev = gpd_data->base.dev;
if (!dev) {
mutex_unlock(&gpd_data->lock);
return NOTIFY_DONE;
}
mutex_unlock(&gpd_data->lock);

for (;;) {
struct generic_pm_domain *genpd;
struct pm_domain_data *pdd;

spin_lock_irq(&dev->power.lock);

pdd = dev->power.subsys_data ?
dev->power.subsys_data->domain_data : NULL;
if (pdd) {
to_gpd_data(pdd)->td.constraint_changed = true;
genpd = dev_to_genpd(dev);
} else {
genpd = ERR_PTR(-ENODATA);
}

spin_unlock_irq(&dev->power.lock);

if (!IS_ERR(genpd)) {
mutex_lock(&genpd->lock);
genpd->max_off_time_changed = true;
mutex_unlock(&genpd->lock);
}

dev = dev->parent;
if (!dev || dev->power.ignore_children)
break;
}

return NOTIFY_DONE;
}

/**
* __pm_genpd_save_device - Save the pre-suspend state of a device.
* @pdd: Domain data of the device to save the state of.
Expand Down Expand Up @@ -381,7 +432,6 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
return 0;
}

genpd->max_off_time_ns = -1;
if (genpd->gov && genpd->gov->power_down_ok) {
if (!genpd->gov->power_down_ok(&genpd->domain))
return -EAGAIN;
Expand Down Expand Up @@ -436,6 +486,7 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
if (elapsed_ns > genpd->power_off_latency_ns) {
genpd->power_off_latency_ns = elapsed_ns;
genpd->max_off_time_changed = true;
if (genpd->name)
pr_warning("%s: Power-off latency exceeded, "
"new value %lld ns\n", genpd->name,
Expand Down Expand Up @@ -496,7 +547,6 @@ static int pm_genpd_runtime_suspend(struct device *dev)
if (dev_gpd_data(dev)->always_on)
return -EBUSY;

dev_gpd_data(dev)->td.effective_constraint_ns = -1;
stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL;
if (stop_ok && !stop_ok(dev))
return -EBUSY;
Expand Down Expand Up @@ -601,6 +651,12 @@ void pm_genpd_poweroff_unused(void)

#else

static inline int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
unsigned long val, void *ptr)
{
return NOTIFY_DONE;
}

static inline void genpd_power_off_work_fn(struct work_struct *work) {}

#define pm_genpd_runtime_suspend NULL
Expand Down Expand Up @@ -1197,6 +1253,14 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
return -EINVAL;

gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
if (!gpd_data)
return -ENOMEM;

mutex_init(&gpd_data->lock);
gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
dev_pm_qos_add_notifier(dev, &gpd_data->nb);

genpd_acquire_lock(genpd);

if (genpd->status == GPD_STATE_POWER_OFF) {
Expand All @@ -1215,26 +1279,35 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
goto out;
}

gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
if (!gpd_data) {
ret = -ENOMEM;
goto out;
}

genpd->device_count++;
genpd->max_off_time_changed = true;

dev->pm_domain = &genpd->domain;
dev_pm_get_subsys_data(dev);

mutex_lock(&gpd_data->lock);
spin_lock_irq(&dev->power.lock);
dev->pm_domain = &genpd->domain;
dev->power.subsys_data->domain_data = &gpd_data->base;
gpd_data->base.dev = dev;
gpd_data->need_restore = false;
list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
gpd_data->need_restore = false;
if (td)
gpd_data->td = *td;

gpd_data->td.constraint_changed = true;
gpd_data->td.effective_constraint_ns = -1;
spin_unlock_irq(&dev->power.lock);
mutex_unlock(&gpd_data->lock);

genpd_release_lock(genpd);

return 0;

out:
genpd_release_lock(genpd);

dev_pm_qos_remove_notifier(dev, &gpd_data->nb);
kfree(gpd_data);
return ret;
}

Expand Down Expand Up @@ -1278,6 +1351,7 @@ int __pm_genpd_of_add_device(struct device_node *genpd_node, struct device *dev,
int pm_genpd_remove_device(struct generic_pm_domain *genpd,
struct device *dev)
{
struct generic_pm_domain_data *gpd_data;
struct pm_domain_data *pdd;
int ret = 0;

Expand All @@ -1295,14 +1369,27 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd,
goto out;
}

genpd->device_count--;
genpd->max_off_time_changed = true;

spin_lock_irq(&dev->power.lock);
dev->pm_domain = NULL;
pdd = dev->power.subsys_data->domain_data;
list_del_init(&pdd->list_node);
dev->power.subsys_data->domain_data = NULL;
dev_pm_put_subsys_data(dev);
kfree(to_gpd_data(pdd));
spin_unlock_irq(&dev->power.lock);

genpd->device_count--;
gpd_data = to_gpd_data(pdd);
mutex_lock(&gpd_data->lock);
pdd->dev = NULL;
mutex_unlock(&gpd_data->lock);

genpd_release_lock(genpd);

dev_pm_qos_remove_notifier(dev, &gpd_data->nb);
kfree(gpd_data);
dev_pm_put_subsys_data(dev);
return 0;

out:
genpd_release_lock(genpd);
Expand Down Expand Up @@ -1673,6 +1760,7 @@ void pm_genpd_init(struct generic_pm_domain *genpd,
genpd->resume_count = 0;
genpd->device_count = 0;
genpd->max_off_time_ns = -1;
genpd->max_off_time_changed = true;
genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend;
genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume;
genpd->domain.ops.runtime_idle = pm_generic_runtime_idle;
Expand Down
45 changes: 42 additions & 3 deletions trunk/drivers/base/power/domain_governor.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -46,18 +46,34 @@ static int dev_update_qos_constraint(struct device *dev, void *data)
bool default_stop_ok(struct device *dev)
{
struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
unsigned long flags;
s64 constraint_ns;

dev_dbg(dev, "%s()\n", __func__);

constraint_ns = dev_pm_qos_read_value(dev);
spin_lock_irqsave(&dev->power.lock, flags);

if (!td->constraint_changed) {
bool ret = td->cached_stop_ok;

spin_unlock_irqrestore(&dev->power.lock, flags);
return ret;
}
td->constraint_changed = false;
td->cached_stop_ok = false;
td->effective_constraint_ns = -1;
constraint_ns = __dev_pm_qos_read_value(dev);

spin_unlock_irqrestore(&dev->power.lock, flags);

if (constraint_ns < 0)
return false;

constraint_ns *= NSEC_PER_USEC;
/*
* We can walk the children without any additional locking, because
* they all have been suspended at this point.
* they all have been suspended at this point and their
* effective_constraint_ns fields won't be modified in parallel with us.
*/
if (!dev->power.ignore_children)
device_for_each_child(dev, &constraint_ns,
Expand All @@ -69,11 +85,13 @@ bool default_stop_ok(struct device *dev)
return false;
}
td->effective_constraint_ns = constraint_ns;
td->cached_stop_ok = constraint_ns > td->stop_latency_ns ||
constraint_ns == 0;
/*
* The children have been suspended already, so we don't need to take
* their stop latencies into account here.
*/
return constraint_ns > td->stop_latency_ns || constraint_ns == 0;
return td->cached_stop_ok;
}

/**
Expand All @@ -90,6 +108,25 @@ static bool default_power_down_ok(struct dev_pm_domain *pd)
s64 min_dev_off_time_ns;
s64 off_on_time_ns;

if (genpd->max_off_time_changed) {
struct gpd_link *link;

/*
* We have to invalidate the cached results for the masters, so
* use the observation that default_power_down_ok() is not
* going to be called for any master until this instance
* returns.
*/
list_for_each_entry(link, &genpd->slave_links, slave_node)
link->master->max_off_time_changed = true;

genpd->max_off_time_changed = false;
genpd->cached_power_down_ok = false;
genpd->max_off_time_ns = -1;
} else {
return genpd->cached_power_down_ok;
}

off_on_time_ns = genpd->power_off_latency_ns +
genpd->power_on_latency_ns;
/*
Expand Down Expand Up @@ -165,6 +202,8 @@ static bool default_power_down_ok(struct dev_pm_domain *pd)
min_dev_off_time_ns = constraint_ns;
}

genpd->cached_power_down_ok = true;

/*
* If the computed minimum device off time is negative, there are no
* latency constraints, so the domain can spend arbitrary time in the
Expand Down
7 changes: 7 additions & 0 deletions trunk/include/linux/pm_domain.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -14,6 +14,7 @@
#include <linux/pm.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/notifier.h>

enum gpd_status {
GPD_STATE_ACTIVE = 0, /* PM domain is active */
Expand Down Expand Up @@ -71,6 +72,8 @@ struct generic_pm_domain {
s64 power_on_latency_ns;
struct gpd_dev_ops dev_ops;
s64 max_off_time_ns; /* Maximum allowed "suspended" time. */
bool max_off_time_changed;
bool cached_power_down_ok;
struct device_node *of_node; /* Node in device tree */
};

Expand All @@ -92,12 +95,16 @@ struct gpd_timing_data {
s64 save_state_latency_ns;
s64 restore_state_latency_ns;
s64 effective_constraint_ns;
bool constraint_changed;
bool cached_stop_ok;
};

struct generic_pm_domain_data {
struct pm_domain_data base;
struct gpd_dev_ops ops;
struct gpd_timing_data td;
struct notifier_block nb;
struct mutex lock;
bool need_restore;
bool always_on;
};
Expand Down

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