PM: sleep: core: Use built-in RCU list checking (42beb82e) · Commits · 戴 / test

This patch passes the cond argument to list_for_each_entry_rcu() to fix the following false-positive lockdep warnings: (with CONFIG_PROVE_RCU_LIST = y) [ 330.302784] ============================= [ 330.302789] WARNING: suspicious RCU usage [ 330.302796] 5.6.0-rc1+ #5 Not tainted [ 330.302801] ----------------------------- [ 330.302808] drivers/base/power/main.c:326 RCU-list traversed in non-reader section!! [ 330.303303] ============================= [ 330.303307] WARNING: suspicious RCU usage [ 330.303311] 5.6.0-rc1+ #5 Not tainted [ 330.303315] ----------------------------- [ 330.303319] drivers/base/power/main.c:1698 RCU-list traversed in non-reader section!! [ 331.934969] ============================= [ 331.934971] WARNING: suspicious RCU usage [ 331.934973] 5.6.0-rc1+ #5 Not tainted [ 331.934975] ----------------------------- [ 331.934977] drivers/base/power/main.c:1238 RCU-list traversed in non-reader section!! [ 332.467772] WARNING: suspicious RCU usage [ 332.467775] 5.6.0-rc1+ #5 Not tainted [ 332.467775] ----------------------------- [ 332.467778] drivers/base/power/main.c:269 RCU-list traversed in non-reader section!! Signed-off-by:

Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com> Signed-off-by:

Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/base/power/main.c

+8 −4

Original line number	Diff line number	Diff line
		@@ -40,6 +40,10 @@

		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, \
		device_links_read_lock_held())

		/*
		* The entries in the dpm_list list are in a depth first order, simply
		* because children are guaranteed to be discovered after parents, and
		@@ -266,7 +270,7 @@ 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(link, &dev->links.suppliers, c_node)
		list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node)
		if (READ_ONCE(link->status) != DL_STATE_DORMANT)
		dpm_wait(link->supplier, async);

		@@ -323,7 +327,7 @@ 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(link, &dev->links.consumers, s_node)
		list_for_each_entry_rcu_locked(link, &dev->links.consumers, s_node)
		if (READ_ONCE(link->status) != DL_STATE_DORMANT)
		dpm_wait(link->consumer, async);

		@@ -1235,7 +1239,7 @@ static void dpm_superior_set_must_resume(struct device *dev)

		idx = device_links_read_lock();

		list_for_each_entry_rcu(link, &dev->links.suppliers, c_node)
		list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node)
		link->supplier->power.must_resume = true;

		device_links_read_unlock(idx);
		@@ -1695,7 +1699,7 @@ static void dpm_clear_superiors_direct_complete(struct device *dev)

		idx = device_links_read_lock();

		list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) {
		list_for_each_entry_rcu_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);

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