Re: [PATCH] PM / runtime: Asynchronous "idle" in pm_runtime_allow()

From: Kevin Hilman
Date: Thu Jun 30 2016 - 18:48:49 EST


"Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> writes:

> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> Arjan reports that it takes a relatively long time to enable runtime
> PM for multiple devices at system startup, because all writes to the
> "control" attribute in sysfs are handled synchronously and if the
> device is suspended as a result of the write, it will block until
> that operation is complete.
>
> That may be avoided by passing the RPM_ASYNC flag to rpm_idle()
> in pm_runtime_allow() which will make it execute the device's
> "idle" callback asynchronously, so writes to "control" changing
> it from "on" to "auto" will return without waiting.
>
> Reported-by: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Reviewed-by: Kevin Hilman <khilman@xxxxxxxxxxxx>