Re: [linux-pm] [PATCH 0/8] Suspend block api (version 8)

Alan Cox
2010-05-27T22:49:14Z

On Thu, 27 May 2010 23:36:05 +0100
Matthew Garrett <mjg59@srcf.ucam.org> wrote:

> On Thu, May 27, 2010 at 11:23:57PM +0100, Alan Cox wrote:
> > On Thu, 27 May 2010 23:09:49 +0100
> > Matthew Garrett <mjg59@srcf.ucam.org> wrote:
> >
> > > On Thu, May 27, 2010 at 11:08:06PM +0100, Alan Cox wrote:
> > >
> > > > This is I believe robust (and has been implemented on some non x86
> > > > boxes). It depends on not forcing running tasks into suspend. That is the
> > > > key.
> > >
> > > We've already established that ACPI systems require us to force running
> > > tasks into suspend. How do we avoid the race in that situation?
> >
> > Android phones do not have ACPI. Embedded platforms do not have ACPI. MID
> > x86 devices do not have ACPI.
>
> It doesn't matter. Right now there's a race condition in terms of
> wakeup events on ACPI systems. What's your proposal for fixing that?

I see it as a different problem - and one that seems to be minimally
pressing to most users jduging by the amount of noise it hasn't caused in
the past seven odd years.

This started because the Android people came to a meeting that was put
together of various folks to try and sort of the big blockage in getting
Android and Linux kernels back towards merging.

I am interested right now in finding a general solution to the Android
case and the fact it looks very similar to the VM, hard RT, gamer and
other related problems although we seem to have diverged from that logic.

I dont think it particularly useful to go off on a mostly unrelated wild
goose chase into ACPI land, especially one based on a premise of changing
all the apps when the hardware will end up fixed faster.

Alan