[PATCH 06/14] PM: domains: Allocate gpd_timing_data dynamically based on governor
Ulf Hansson
ulf.hansson at linaro.org
Wed May 11 07:56:56 PDT 2022
If a genpd doesn't have an associated governor assigned, there's really no
point to allocate the per device gpd_timing_data, as the data isn't being
used by a governor anyway.
To avoid wasting memory, let's therefore convert the corresponding td
variable in the struct generic_pm_domain_data into a pointer and manage the
allocation of its data dynamically.
Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
---
drivers/base/power/domain.c | 48 +++++++++++++++++++---------
drivers/base/power/domain_governor.c | 9 ++++--
include/linux/pm_domain.h | 2 +-
3 files changed, 40 insertions(+), 19 deletions(-)
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index a3e727c9a4fa..ca86fb3db901 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -773,13 +773,16 @@ static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
for (;;) {
struct generic_pm_domain *genpd;
struct pm_domain_data *pdd;
+ struct gpd_timing_data *td;
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;
+ td = to_gpd_data(pdd)->td;
+ if (td)
+ td->constraint_changed = true;
genpd = dev_to_genpd(dev);
} else {
genpd = ERR_PTR(-ENODATA);
@@ -875,7 +878,7 @@ static int genpd_runtime_suspend(struct device *dev)
struct generic_pm_domain *genpd;
bool (*suspend_ok)(struct device *__dev);
struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
- struct gpd_timing_data *td = &gpd_data->td;
+ struct gpd_timing_data *td = gpd_data->td;
bool runtime_pm = pm_runtime_enabled(dev);
ktime_t time_start;
s64 elapsed_ns;
@@ -915,7 +918,7 @@ static int genpd_runtime_suspend(struct device *dev)
/* Update suspend latency value if the measured time exceeds it. */
if (runtime_pm) {
elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
- if (elapsed_ns > td->suspend_latency_ns) {
+ if (td && (elapsed_ns > td->suspend_latency_ns)) {
td->suspend_latency_ns = elapsed_ns;
dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
elapsed_ns);
@@ -951,7 +954,7 @@ static int genpd_runtime_resume(struct device *dev)
{
struct generic_pm_domain *genpd;
struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
- struct gpd_timing_data *td = &gpd_data->td;
+ struct gpd_timing_data *td = gpd_data->td;
bool runtime_pm = pm_runtime_enabled(dev);
ktime_t time_start;
s64 elapsed_ns;
@@ -999,7 +1002,7 @@ static int genpd_runtime_resume(struct device *dev)
/* Update resume latency value if the measured time exceeds it. */
if (timed && runtime_pm) {
elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
- if (elapsed_ns > td->resume_latency_ns) {
+ if (td && (elapsed_ns > td->resume_latency_ns)) {
td->resume_latency_ns = elapsed_ns;
dev_dbg(dev, "resume latency exceeded, %lld ns\n",
elapsed_ns);
@@ -1496,9 +1499,11 @@ EXPORT_SYMBOL_GPL(dev_pm_genpd_resume);
#endif /* CONFIG_PM_SLEEP */
-static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev)
+static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
+ bool has_governor)
{
struct generic_pm_domain_data *gpd_data;
+ struct gpd_timing_data *td;
int ret;
ret = dev_pm_get_subsys_data(dev);
@@ -1512,26 +1517,38 @@ static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev)
}
gpd_data->base.dev = dev;
- gpd_data->td.constraint_changed = true;
- gpd_data->td.effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
gpd_data->next_wakeup = KTIME_MAX;
- spin_lock_irq(&dev->power.lock);
+ /* Allocate data used by a governor. */
+ if (has_governor) {
+ td = kzalloc(sizeof(*td), GFP_KERNEL);
+ if (!td) {
+ ret = -ENOMEM;
+ goto err_free;
+ }
- if (dev->power.subsys_data->domain_data) {
- ret = -EINVAL;
- goto err_free;
+ td->constraint_changed = true;
+ td->effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
+ gpd_data->td = td;
}
- dev->power.subsys_data->domain_data = &gpd_data->base;
+ spin_lock_irq(&dev->power.lock);
+
+ if (dev->power.subsys_data->domain_data)
+ ret = -EINVAL;
+ else
+ dev->power.subsys_data->domain_data = &gpd_data->base;
spin_unlock_irq(&dev->power.lock);
+ if (ret)
+ goto err_free;
+
return gpd_data;
err_free:
- spin_unlock_irq(&dev->power.lock);
+ kfree(gpd_data->td);
kfree(gpd_data);
err_put:
dev_pm_put_subsys_data(dev);
@@ -1547,6 +1564,7 @@ static void genpd_free_dev_data(struct device *dev,
spin_unlock_irq(&dev->power.lock);
+ kfree(gpd_data->td);
kfree(gpd_data);
dev_pm_put_subsys_data(dev);
}
@@ -1611,7 +1629,7 @@ static int 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 = genpd_alloc_dev_data(dev);
+ gpd_data = genpd_alloc_dev_data(dev, genpd->gov);
if (IS_ERR(gpd_data))
return PTR_ERR(gpd_data);
diff --git a/drivers/base/power/domain_governor.c b/drivers/base/power/domain_governor.c
index c13e44823f16..62be9b3f8c90 100644
--- a/drivers/base/power/domain_governor.c
+++ b/drivers/base/power/domain_governor.c
@@ -18,6 +18,8 @@ static int dev_update_qos_constraint(struct device *dev, void *data)
s64 constraint_ns;
if (dev->power.subsys_data && dev->power.subsys_data->domain_data) {
+ struct gpd_timing_data *td = dev_gpd_data(dev)->td;
+
/*
* Only take suspend-time QoS constraints of devices into
* account, because constraints updated after the device has
@@ -25,7 +27,8 @@ static int dev_update_qos_constraint(struct device *dev, void *data)
* anyway. In order for them to take effect, the device has to
* be resumed and suspended again.
*/
- constraint_ns = dev_gpd_data(dev)->td.effective_constraint_ns;
+ constraint_ns = td ? td->effective_constraint_ns :
+ PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
} else {
/*
* The child is not in a domain and there's no info on its
@@ -49,7 +52,7 @@ static int dev_update_qos_constraint(struct device *dev, void *data)
*/
static bool default_suspend_ok(struct device *dev)
{
- struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
+ struct gpd_timing_data *td = dev_gpd_data(dev)->td;
unsigned long flags;
s64 constraint_ns;
@@ -215,7 +218,7 @@ static bool __default_power_down_ok(struct dev_pm_domain *pd,
* domain to turn off and on (that's how much time it will
* have to wait worst case).
*/
- td = &to_gpd_data(pdd)->td;
+ td = to_gpd_data(pdd)->td;
constraint_ns = td->effective_constraint_ns;
/*
* Zero means "no suspend at all" and this runs only when all
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index 043d48e4420a..126a4b9ab215 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -193,7 +193,7 @@ struct pm_domain_data {
struct generic_pm_domain_data {
struct pm_domain_data base;
- struct gpd_timing_data td;
+ struct gpd_timing_data *td;
struct notifier_block nb;
struct notifier_block *power_nb;
int cpu;
--
2.25.1
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