PM: core: Annotate loops walking device links as _srcu

Since SRCU is used for the protection of device link lists, the loops
over device link lists in multiple places in drivers/base/power/main.c
and in pm_runtime_get_suppliers() should be annotated as _srcu rather
than as _rcu which is the case currently.

Change the annotations accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/2393512.ElGaqSPkdT@rafael.j.wysocki

Author: rafaeljw

drivers/base/power/main.c

@@ -40,8 +40,8 @@
 
 typedef int (*pm_callback_t)(struct device *);
 
-#define list_for_each_entry_rcu_locked(pos, head, member) \
-	list_for_each_entry_rcu(pos, head, member, \
+#define list_for_each_entry_srcu_locked(pos, head, member) \
+	list_for_each_entry_srcu(pos, head, member, \
 			device_links_read_lock_held())
 
 /*
@@ -281,7 +281,7 @@ static void dpm_wait_for_suppliers(struct device *dev, bool async)
 	 * callbacks freeing the link objects for the links in the list we're
 	 * walking.
 	 */
-	list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node)
+	list_for_each_entry_srcu_locked(link, &dev->links.suppliers, c_node)
 		if (READ_ONCE(link->status) != DL_STATE_DORMANT)
 			dpm_wait(link->supplier, async);
 
@@ -338,7 +338,7 @@ static void dpm_wait_for_consumers(struct device *dev, bool async)
 	 * continue instead of trying to continue in parallel with its
 	 * unregistration).
 	 */
-	list_for_each_entry_rcu_locked(link, &dev->links.consumers, s_node)
+	list_for_each_entry_srcu_locked(link, &dev->links.consumers, s_node)
 		if (READ_ONCE(link->status) != DL_STATE_DORMANT)
 			dpm_wait(link->consumer, async);
 
@@ -675,7 +675,7 @@ static void dpm_async_resume_subordinate(struct device *dev, async_func_t func)
 	idx = device_links_read_lock();
 
 	/* Start processing the device's "async" consumers. */
-	list_for_each_entry_rcu_locked(link, &dev->links.consumers, s_node)
+	list_for_each_entry_srcu_locked(link, &dev->links.consumers, s_node)
 		if (READ_ONCE(link->status) != DL_STATE_DORMANT)
 			dpm_async_with_cleanup(link->consumer, func);
 
@@ -1330,7 +1330,7 @@ static void dpm_async_suspend_superior(struct device *dev, async_func_t func)
 	idx = device_links_read_lock();
 
 	/* Start processing the device's "async" suppliers. */
-	list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node)
+	list_for_each_entry_srcu_locked(link, &dev->links.suppliers, c_node)
 		if (READ_ONCE(link->status) != DL_STATE_DORMANT)
 			dpm_async_with_cleanup(link->supplier, func);
 
@@ -1384,7 +1384,7 @@ static void dpm_superior_set_must_resume(struct device *dev)
 
 	idx = device_links_read_lock();
 
-	list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node)
+	list_for_each_entry_srcu_locked(link, &dev->links.suppliers, c_node)
 		link->supplier->power.must_resume = true;
 
 	device_links_read_unlock(idx);
@@ -1813,7 +1813,7 @@ static void dpm_clear_superiors_direct_complete(struct device *dev)
 
 	idx = device_links_read_lock();
 
-	list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) {
+	list_for_each_entry_srcu_locked(link, &dev->links.suppliers, c_node) {
 		spin_lock_irq(&link->supplier->power.lock);
 		link->supplier->power.direct_complete = false;
 		spin_unlock_irq(&link->supplier->power.lock);
@@ -2065,7 +2065,7 @@ static bool device_prepare_smart_suspend(struct device *dev)
 
 	idx = device_links_read_lock();
 
-	list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) {
+	list_for_each_entry_srcu_locked(link, &dev->links.suppliers, c_node) {
 		if (!device_link_test(link, DL_FLAG_PM_RUNTIME))
 			continue;
 

drivers/base/power/runtime.c

@@ -1903,8 +1903,8 @@ void pm_runtime_get_suppliers(struct device *dev)
 
 	idx = device_links_read_lock();
 
-	list_for_each_entry_rcu(link, &dev->links.suppliers, c_node,
-				device_links_read_lock_held())
+	list_for_each_entry_srcu(link, &dev->links.suppliers, c_node,
+				 device_links_read_lock_held())
 		if (device_link_test(link, DL_FLAG_PM_RUNTIME)) {
 			link->supplier_preactivated = true;
 			pm_runtime_get_sync(link->supplier);