Re: [RFC][PATCH 1/3] PM: Asynchronous resume of devices

From: Rafael J. Wysocki
Date: Sat Aug 22 2009 - 17:44:37 EST


On Saturday 22 August 2009, Pavel Machek wrote:
> Hi!
>
> > > Do we really need async for noirq handlers?
> >
> > Yes, we do. Specifically, for PCI.
>
> Do noirq parts of PCI handling really so long that we need to make
> them async?

I think so. It may get 10 ms to handle a PCI device at this stage usually
and this is all waiting. If you multiply that by the number of PCI devices ...

> Async in normal paths looks pretty much okay to me, but in noirq
> parts, locking is tricky, etc...

The locking is actually simpler in that case.

Thanks,
Rafael
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