Re: [PATCH 0/8] Suspend block api (version 6)

[Matthew Garrett]

On Tue, May 11, 2010 at 10:48:58AM -0700, Tony Lindgren wrote:
> * Matthew Garrett <mjg@xxxxxxxxxx> [100511 10:25]:
> > On Tue, May 11, 2010 at 10:24:43AM -0700, Tony Lindgren wrote:
> > 
> > > For the failed suspend path in the kernel, currently the kernel would
> > > unwind back all the drivers because of the failed driver, but that path
> > > should be possible to optimize.
> > 
> > If you think it's possible to make this work then feel free to. But at 
> > the point where you're adding code to every driver's suspend function to 
> > determine whether or not it's got any pending events that userspace 
> > hasn't consumed yet, and adding code to every bit of userspace to allow 
> > it to indicate whether or not it's busy consuming events or just busy 
> > drawing 3D bouncing cattle, I think you've reinvented suspend blocks.
> 
> Sorry, I have a working system that idles nicely and stays up on
> batteries for a long time while running. I don't need to implement
> anything like this :)

Right, but your system will only idle nicely if all of your userspace is 
well-written. It's not reasonable to expect that all userspace will be 
well-written and thus it's necessary to implement a power management 
strategy that doesn't require that. Refusing an implementation that 
achieves that on the basis that there's hypothetically a better way of 
doing it is entirely unreasonable.

-- 
Matthew Garrett | mjg59@xxxxxxxxxxxxx
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