PM: runtime: Drop pm_runtime_clean_up_links()

commit d6e36668598154820177bfd78c1621d8e6c580a2 upstream.

After commit d12544fb2aa9 ("PM: runtime: Remove link state checks in
rpm_get/put_supplier()") nothing prevents the consumer device's
runtime PM from acquiring additional references to the supplier
device after pm_runtime_clean_up_links() has run (or even while it
is running), so calling this function from __device_release_driver()
may be pointless (or even harmful).

Moreover, it ignores stateless device links, so the runtime PM
handling of managed and stateless device links is inconsistent
because of it, so better get rid of it entirely.

Fixes: d12544fb2aa9 ("PM: runtime: Remove link state checks in rpm_get/put_supplier()")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 5.1+ <stable@vger.kernel.org> # 5.1+
Tested-by: Xiang Chen <chenxiang66@hisilicon.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 84e757860ebb94180fe3b0149e253e5c5f0e8e13..85463c4f7653383e3f58548925535cfa312d6c81 100644 (file)
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -1121,7 +1121,6 @@ static void __device_release_driver(struct device *dev, struct device *parent)
                }
 
                pm_runtime_get_sync(dev);
-               pm_runtime_clean_up_links(dev);
 
                driver_sysfs_remove(dev);
 

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index 159e9c6e16c2d66d2e1cdf20271c75917ad288a8..137a7ba053d7873d0022c0a3838b55fa2c31588f 100644 (file)
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -1615,42 +1615,6 @@ void pm_runtime_remove(struct device *dev)
        pm_runtime_reinit(dev);
 }
 
-/**
- * pm_runtime_clean_up_links - Prepare links to consumers for driver removal.
- * @dev: Device whose driver is going to be removed.
- *
- * Check links from this device to any consumers and if any of them have active
- * runtime PM references to the device, drop the usage counter of the device
- * (as many times as needed).
- *
- * Links with the DL_FLAG_MANAGED flag unset are ignored.
- *
- * Since the device is guaranteed to be runtime-active at the point this is
- * called, nothing else needs to be done here.
- *
- * Moreover, this is called after device_links_busy() has returned 'false', so
- * the status of each link is guaranteed to be DL_STATE_SUPPLIER_UNBIND and
- * therefore rpm_active can't be manipulated concurrently.
- */
-void pm_runtime_clean_up_links(struct device *dev)
-{
-       struct device_link *link;
-       int idx;
-
-       idx = device_links_read_lock();
-
-       list_for_each_entry_rcu(link, &dev->links.consumers, s_node,
-                               device_links_read_lock_held()) {
-               if (!(link->flags & DL_FLAG_MANAGED))
-                       continue;
-
-               while (refcount_dec_not_one(&link->rpm_active))
-                       pm_runtime_put_noidle(dev);
-       }
-
-       device_links_read_unlock(idx);
-}
-
 /**
  * pm_runtime_get_suppliers - Resume and reference-count supplier devices.
  * @dev: Consumer device.

diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h
index d805fb1ae880cade0ec00889ff28e1739ebd8ccd..fe61e3b9a9ca211296695499eebceba75a11cbba 100644 (file)
--- a/include/linux/pm_runtime.h
+++ b/include/linux/pm_runtime.h
@@ -54,7 +54,6 @@ extern u64 pm_runtime_autosuspend_expiration(struct device *dev);
 extern void pm_runtime_update_max_time_suspended(struct device *dev,
                                                 s64 delta_ns);
 extern void pm_runtime_set_memalloc_noio(struct device *dev, bool enable);
-extern void pm_runtime_clean_up_links(struct device *dev);
 extern void pm_runtime_get_suppliers(struct device *dev);
 extern void pm_runtime_put_suppliers(struct device *dev);
 extern void pm_runtime_new_link(struct device *dev);
@@ -173,7 +172,6 @@ static inline u64 pm_runtime_autosuspend_expiration(
                                struct device *dev) { return 0; }
 static inline void pm_runtime_set_memalloc_noio(struct device *dev,
                                                bool enable){}
-static inline void pm_runtime_clean_up_links(struct device *dev) {}
 static inline void pm_runtime_get_suppliers(struct device *dev) {}
 static inline void pm_runtime_put_suppliers(struct device *dev) {}
 static inline void pm_runtime_new_link(struct device *dev) {}