Commit 06799631 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

PM: sleep: Make async suspend handle suppliers like parents 



Avoid starting "async" suspend processing upfront for devices that have
consumers and start "async" suspend processing for a device's suppliers
right after suspending 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/3384525.44csPzL39Z@rjwysocki.net
parent ed18738f

drivers/base/power/main.c

+31 −6
Original line number Diff line number Diff line
@@ -1276,10 +1276,15 @@ static bool dpm_leaf_device(struct device *dev) 
		return false;

	}



	return true;

	/*

	 * 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 list_empty(&dev->links.consumers);

}



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

static bool dpm_async_suspend_parent(struct device *dev, async_func_t func)

{

	guard(mutex)(&dpm_list_mtx);
@@ -1291,11 +1296,31 @@ static void dpm_async_suspend_parent(struct device *dev, async_func_t func) 
	 * deleted before it.

	 */

	if (!device_pm_initialized(dev))

		return;

		return false;



	/* Start processing the device's parent if it is "async". */

	if (dev->parent)

		dpm_async_with_cleanup(dev->parent, func);



	return true;

}



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

{

	struct device_link *link;

	int idx;



	if (!dpm_async_suspend_parent(dev, func))

		return;



	idx = device_links_read_lock();



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

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

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

			dpm_async_with_cleanup(link->supplier, func);



	device_links_read_unlock(idx);

}



/**
@@ -1419,7 +1444,7 @@ static int device_suspend_noirq(struct device *dev, pm_message_t state, bool asy 
	if (error || async_error)

		return error;



	dpm_async_suspend_parent(dev, async_suspend_noirq);

	dpm_async_suspend_superior(dev, async_suspend_noirq);



	return 0;

}
@@ -1615,7 +1640,7 @@ static int device_suspend_late(struct device *dev, pm_message_t state, bool asyn 
	if (error || async_error)

		return error;



	dpm_async_suspend_parent(dev, async_suspend_late);

	dpm_async_suspend_superior(dev, async_suspend_late);



	return 0;

}
@@ -1906,7 +1931,7 @@ static int device_suspend(struct device *dev, pm_message_t state, bool async) 
	if (error || async_error)

		return error;



	dpm_async_suspend_parent(dev, async_suspend);

	dpm_async_suspend_superior(dev, async_suspend);



	return 0;

}