Re: [RFC][PATCH 0/7] PM: Asynchronous suspend and resume (updated)

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Tuesday 18 August 2009, Zhang Rui wrote:
> On Mon, 2009-08-17 at 08:15 +0800, Rafael J. Wysocki wrote:
> > On Wednesday 12 August 2009, Rafael J. Wysocki wrote:
> > > Hi,
> > > 
> > > The following patches introduce a mechanism allowing us to execute device
> > > drivers' suspend and resume callbacks asynchronously during system sleep
> > > transitions, such as suspend to RAM.  The idea is explained in the [1/1] patch
> > > message.
> > 
> > Changes:
> > 
> > * Added [1/7] that fixes kerneldoc comments in drivers/base/power/main.c
> >   (this is a 2.6.32 candidate).
> > 
> > * Added [2/7] adding a framework for representing PM link (idea described
> >   in the patch message).
> > 
> > * [3/7] is the async resume patch (idea described in the patch message).
> > 
> > * [4/7] is the async suspend patch.
> > 
> > * [5/7] - [7/7] set async_suspend for devices in a few selected subsystems.
> > 
> > The patches have been tested on HP nx6325.
> > 
> I tried this patch set and it does work. :)
> But unfortunately it doesn't save too much time.
> 
> I still think that the child device should inherit its parent's
> async_suspend flag to do the asynchronous resume more efficiently.
> 
> or at least we should provide such an interface
> in drivers/base/power/common.c, so that device can tell the device core
> to inherit this flag if there is no off-tree dependency.

Well, I'd prefer to identify all of the off-tree dependencies that have to be
taken into account and handle all devices asynchronously.

Thanks,
Rafael