From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Add an optimization (on top of previous changes) to avoid calling
pm_runtime_blocked(), which involves acquiring the device's PM spinlock,
for devices with no PM callbacks and runtime PM "blocked".
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/base/power/main.c | 16 +++++++++-------
drivers/base/power/runtime.c | 9 +++++++--
include/linux/pm_runtime.h | 4 ++--
3 files changed, 18 insertions(+), 11 deletions(-)
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -1796,16 +1796,14 @@
/*
* The "smart suspend" feature is enabled for devices whose drivers ask
- * for it and for devices without PM callbacks unless runtime PM is
- * disabled and enabling it is blocked for them.
+ * for it and for devices without PM callbacks.
*
* However, if "smart suspend" is not enabled for the device's parent
* or any of its suppliers that take runtime PM into account, it cannot
* be enabled for the device either.
*/
- dev->power.smart_suspend = (dev->power.no_pm_callbacks ||
- dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND)) &&
- !pm_runtime_blocked(dev);
+ dev->power.smart_suspend = dev->power.no_pm_callbacks ||
+ dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND);
if (!dev_pm_smart_suspend(dev))
return;
@@ -1843,6 +1841,7 @@
static int device_prepare(struct device *dev, pm_message_t state)
{
int (*callback)(struct device *) = NULL;
+ bool no_runtime_pm;
int ret = 0;
/*
@@ -1858,7 +1857,7 @@
* suspend-resume cycle is complete, so prepare to trigger a warning on
* subsequent attempts to enable it.
*/
- pm_runtime_block_if_disabled(dev);
+ no_runtime_pm = pm_runtime_block_if_disabled(dev);
if (dev->power.syscore)
return 0;
@@ -1893,7 +1892,10 @@
pm_runtime_put(dev);
return ret;
}
- device_prepare_smart_suspend(dev);
+ /* Do not enable "smart suspend" for devices without runtime PM. */
+ if (!no_runtime_pm)
+ device_prepare_smart_suspend(dev);
+
/*
* A positive return value from ->prepare() means "this device appears
* to be runtime-suspended and its state is fine, so if it really is
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -1460,14 +1460,19 @@
}
EXPORT_SYMBOL_GPL(pm_runtime_barrier);
-void pm_runtime_block_if_disabled(struct device *dev)
+bool pm_runtime_block_if_disabled(struct device *dev)
{
+ bool ret;
+
spin_lock_irq(&dev->power.lock);
- if (dev->power.disable_depth && dev->power.last_status == RPM_INVALID)
+ ret = dev->power.disable_depth && dev->power.last_status == RPM_INVALID;
+ if (ret)
dev->power.last_status = RPM_BLOCKED;
spin_unlock_irq(&dev->power.lock);
+
+ return ret;
}
void pm_runtime_unblock(struct device *dev)
--- a/include/linux/pm_runtime.h
+++ b/include/linux/pm_runtime.h
@@ -77,7 +77,7 @@
extern int pm_schedule_suspend(struct device *dev, unsigned int delay);
extern int __pm_runtime_set_status(struct device *dev, unsigned int status);
extern int pm_runtime_barrier(struct device *dev);
-extern void pm_runtime_block_if_disabled(struct device *dev);
+extern bool pm_runtime_block_if_disabled(struct device *dev);
extern void pm_runtime_unblock(struct device *dev);
extern void pm_runtime_enable(struct device *dev);
extern void __pm_runtime_disable(struct device *dev, bool check_resume);
@@ -274,7 +274,7 @@
static inline int __pm_runtime_set_status(struct device *dev,
unsigned int status) { return 0; }
static inline int pm_runtime_barrier(struct device *dev) { return 0; }
-static inline void pm_runtime_block_if_disabled(struct device *dev) {}
+static inline bool pm_runtime_block_if_disabled(struct device *dev) { return true; }
static inline void pm_runtime_unblock(struct device *dev) {}
static inline void pm_runtime_enable(struct device *dev) {}
static inline void __pm_runtime_disable(struct device *dev, bool c) {}
