Commit ed18738f authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

PM: sleep: Make async resume handle consumers like children 



Avoid starting "async" resume processing upfront for devices that have
suppliers and start "async" resume processing for a device's consumers
right after resuming the device itself.

Suggested-by: default avatarSaravana Kannan <saravanak@google.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: default avatarSudeep Holla <sudeep.holla@arm.com>
Link: https://patch.msgid.link/3378088.aeNJFYEL58@rjwysocki.net
parent 5e8be76a

drivers/base/power/main.c

+28 −8
Original line number Diff line number Diff line
@@ -647,14 +647,27 @@ static void dpm_async_resume_children(struct device *dev, async_func_t func) 
	/*

	 * Start processing "async" children of the device unless it's been

	 * started already for them.

	 *

	 * This could have been done for the device's "async" consumers too, but

	 * they either need to wait for their parents or the processing has

	 * already started for them after their parents were processed.

	 */

	device_for_each_child(dev, func, dpm_async_with_cleanup);

}



static void dpm_async_resume_subordinate(struct device *dev, async_func_t func)

{

	struct device_link *link;

	int idx;



	dpm_async_resume_children(dev, func);



	idx = device_links_read_lock();



	/* Start processing the device's "async" consumers. */

	list_for_each_entry_rcu(link, &dev->links.consumers, s_node)

		if (READ_ONCE(link->status) != DL_STATE_DORMANT)

			dpm_async_with_cleanup(link->consumer, func);



	device_links_read_unlock(idx);

}



static void dpm_clear_async_state(struct device *dev)

{

	reinit_completion(&dev->power.completion);
@@ -663,7 +676,14 @@ static void dpm_clear_async_state(struct device *dev) 


static bool dpm_root_device(struct device *dev)

{

	return !dev->parent;

	lockdep_assert_held(&dpm_list_mtx);



	/*

	 * Since this function is required to run under dpm_list_mtx, the

	 * list_empty() below will only return true if the device's list of

	 * consumers is actually empty before calling it.

	 */

	return !dev->parent && list_empty(&dev->links.suppliers);

}



static void async_resume_noirq(void *data, async_cookie_t cookie);
@@ -752,7 +772,7 @@ static void device_resume_noirq(struct device *dev, pm_message_t state, bool asy 
		pm_dev_err(dev, state, async ? " async noirq" : " noirq", error);

	}



	dpm_async_resume_children(dev, async_resume_noirq);

	dpm_async_resume_subordinate(dev, async_resume_noirq);

}



static void async_resume_noirq(void *data, async_cookie_t cookie)
@@ -895,7 +915,7 @@ static void device_resume_early(struct device *dev, pm_message_t state, bool asy 
		pm_dev_err(dev, state, async ? " async early" : " early", error);

	}



	dpm_async_resume_children(dev, async_resume_early);

	dpm_async_resume_subordinate(dev, async_resume_early);

}



static void async_resume_early(void *data, async_cookie_t cookie)
@@ -1071,7 +1091,7 @@ static void device_resume(struct device *dev, pm_message_t state, bool async) 
		pm_dev_err(dev, state, async ? " async" : "", error);

	}



	dpm_async_resume_children(dev, async_resume);

	dpm_async_resume_subordinate(dev, async_resume);

}



static void async_resume(void *data, async_cookie_t cookie)