Re: [PATCH 5/9] driver/core: Convert to use built-in RCU list checking (v1)
From: Paul E. McKenney <hidden>
Date: 2019-07-16 18:42:34
Also in:
linux-acpi, linux-doc, linux-pci, linux-pm, lkml, rcu
On Mon, Jul 15, 2019 at 10:37:01AM -0400, Joel Fernandes (Google) wrote:
list_for_each_entry_rcu has built-in RCU and lock checking. Make use of it in driver core. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Joel Fernandes (Google) <redacted>
This one looks ready. Thanx, Paul
quoted hunk ↗ jump to hunk
--- drivers/base/base.h | 1 + drivers/base/core.c | 10 ++++++++++ drivers/base/power/runtime.c | 15 ++++++++++----- 3 files changed, 21 insertions(+), 5 deletions(-)diff --git a/drivers/base/base.h b/drivers/base/base.h index b405436ee28e..0d32544b6f91 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h@@ -165,6 +165,7 @@ static inline int devtmpfs_init(void) { return 0; } /* Device links support */ extern int device_links_read_lock(void); extern void device_links_read_unlock(int idx); +extern int device_links_read_lock_held(void); extern int device_links_check_suppliers(struct device *dev); extern void device_links_driver_bound(struct device *dev); extern void device_links_driver_cleanup(struct device *dev);diff --git a/drivers/base/core.c b/drivers/base/core.c index da84a73f2ba6..85e82f38717f 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c@@ -68,6 +68,11 @@ void device_links_read_unlock(int idx) { srcu_read_unlock(&device_links_srcu, idx); } + +int device_links_read_lock_held(void) +{ + return srcu_read_lock_held(&device_links_srcu); +} #else /* !CONFIG_SRCU */ static DECLARE_RWSEM(device_links_lock);@@ -91,6 +96,11 @@ void device_links_read_unlock(int not_used) { up_read(&device_links_lock); } + +int device_links_read_lock_held(void) +{ + return lock_is_held(&device_links_lock); +} #endif /* !CONFIG_SRCU */ /**diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 952a1e7057c7..7a10e8379a70 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c@@ -287,7 +287,8 @@ static int rpm_get_suppliers(struct device *dev) { struct device_link *link; - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) { + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) { int retval; if (!(link->flags & DL_FLAG_PM_RUNTIME) ||@@ -309,7 +310,8 @@ static void rpm_put_suppliers(struct device *dev) { struct device_link *link; - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) { + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) { if (READ_ONCE(link->status) == DL_STATE_SUPPLIER_UNBIND) continue;@@ -1640,7 +1642,8 @@ void pm_runtime_clean_up_links(struct device *dev) idx = device_links_read_lock(); - list_for_each_entry_rcu(link, &dev->links.consumers, s_node) { + list_for_each_entry_rcu(link, &dev->links.consumers, s_node, + device_links_read_lock_held()) { if (link->flags & DL_FLAG_STATELESS) continue;@@ -1662,7 +1665,8 @@ void pm_runtime_get_suppliers(struct device *dev) idx = device_links_read_lock(); - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) if (link->flags & DL_FLAG_PM_RUNTIME) { link->supplier_preactivated = true; refcount_inc(&link->rpm_active);@@ -1683,7 +1687,8 @@ void pm_runtime_put_suppliers(struct device *dev) idx = device_links_read_lock(); - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) if (link->supplier_preactivated) { link->supplier_preactivated = false; if (refcount_dec_not_one(&link->rpm_active))-- 2.22.0.510.g264f2c817a-goog