PM / Domains: Use power.sybsys_data to reduce overhead

Currently pm_genpd_runtime_resume() has to walk the list of devices
from the device's PM domain to find the corresponding device list
object containing the need_restore field to check if the driver's
.runtime_resume() callback should be executed for the device.
This is suboptimal and can be simplified by using power.sybsys_data
to store device information used by the generic PM domains code.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

3 files changed, 19 insertions, 6 deletions

diff --git a/include/linux/pm.h b/include/linux/pm.h
index c6b5a0a41ab3..ed10f24d5259 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -421,12 +421,21 @@ enum rpm_request {
 
 struct wakeup_source;
 
+struct pm_domain_data {
+        struct list_head list_node;
+        struct device *dev;
+        bool need_restore;
+};
+
 struct pm_subsys_data {
         spinlock_t lock;
         unsigned int refcount;
 #ifdef CONFIG_PM_CLK
         struct list_head clock_list;
 #endif
+#ifdef CONFIG_PM_GENERIC_DOMAINS
+        struct pm_domain_data domain_data;
+#endif
 };
 
 struct dev_pm_info {
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index bf679f59f9a8..5cce46c2d926 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -61,12 +61,6 @@ struct gpd_link {
         struct list_head slave_node;
 };
 
-struct dev_list_entry {
-        struct list_head node;
-        struct device *dev;
-        bool need_restore;
-};
-
 #ifdef CONFIG_PM_GENERIC_DOMAINS
 extern int pm_genpd_add_device(struct generic_pm_domain *genpd,
                                struct device *dev);
diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h
index 6b90630e3c98..a5a41a850efb 100644
--- a/include/linux/pm_runtime.h
+++ b/include/linux/pm_runtime.h
@@ -258,6 +258,12 @@ struct pm_clk_notifier_block {
 };
 
 #ifdef CONFIG_PM_CLK
+static inline bool pm_clk_no_clocks(struct device *dev)
+{
+        return dev && dev->power.subsys_data
+                && list_empty(&dev->power.subsys_data->clock_list);
+}
+
 extern void pm_clk_init(struct device *dev);
 extern int pm_clk_create(struct device *dev);
 extern void pm_clk_destroy(struct device *dev);
@@ -266,6 +272,10 @@ extern void pm_clk_remove(struct device *dev, const char *con_id);
 extern int pm_clk_suspend(struct device *dev);
 extern int pm_clk_resume(struct device *dev);
 #else
+static inline bool pm_clk_no_clocks(struct device *dev)
+{
+        return true;
+}
 static inline void pm_clk_init(struct device *dev)
 {
 }