From b06c0b2f087ab498d51d50f5ae353133b602f614 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 12 Jun 2018 10:24:13 +0200 Subject: [PATCH] Revert "PM / runtime: Fixup reference counting of device link suppliers at probe" Revert commit 1e8378619841 (PM / runtime: Fixup reference counting of device link suppliers at probe), as it has introduced a regression and the condition it was designed to address should be covered by the existing code. Reported-by: Marek Szyprowski Signed-off-by: Rafael J. Wysocki --- drivers/base/dd.c | 3 ++- drivers/base/power/runtime.c | 27 ++++++++++++++++++++++++--- include/linux/pm_runtime.h | 6 ++++-- 3 files changed, 30 insertions(+), 6 deletions(-) diff --git a/drivers/base/dd.c b/drivers/base/dd.c index a41c91b..10454fe 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -580,7 +580,7 @@ int driver_probe_device(struct device_driver *drv, struct device *dev) pr_debug("bus: '%s': %s: matched device %s with driver %s\n", drv->bus->name, __func__, dev_name(dev), drv->name); - pm_runtime_resume_suppliers(dev); + pm_runtime_get_suppliers(dev); if (dev->parent) pm_runtime_get_sync(dev->parent); @@ -591,6 +591,7 @@ int driver_probe_device(struct device_driver *drv, struct device *dev) if (dev->parent) pm_runtime_put(dev->parent); + pm_runtime_put_suppliers(dev); return ret; } diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index c6030f1..beb85c3 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -1563,16 +1563,37 @@ void pm_runtime_clean_up_links(struct device *dev) } /** - * pm_runtime_resume_suppliers - Resume supplier devices. + * pm_runtime_get_suppliers - Resume and reference-count supplier devices. * @dev: Consumer device. */ -void pm_runtime_resume_suppliers(struct device *dev) +void pm_runtime_get_suppliers(struct device *dev) { + struct device_link *link; int idx; idx = device_links_read_lock(); - rpm_get_suppliers(dev); + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) + if (link->flags & DL_FLAG_PM_RUNTIME) + pm_runtime_get_sync(link->supplier); + + device_links_read_unlock(idx); +} + +/** + * pm_runtime_put_suppliers - Drop references to supplier devices. + * @dev: Consumer device. + */ +void pm_runtime_put_suppliers(struct device *dev) +{ + struct device_link *link; + int idx; + + idx = device_links_read_lock(); + + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) + if (link->flags & DL_FLAG_PM_RUNTIME) + pm_runtime_put(link->supplier); device_links_read_unlock(idx); } diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h index db5dbbf..f0fc470 100644 --- a/include/linux/pm_runtime.h +++ b/include/linux/pm_runtime.h @@ -56,7 +56,8 @@ 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_resume_suppliers(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); extern void pm_runtime_drop_link(struct device *dev); @@ -172,7 +173,8 @@ static inline unsigned long pm_runtime_autosuspend_expiration( 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_resume_suppliers(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) {} static inline void pm_runtime_drop_link(struct device *dev) {} -- 2.7.4