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

From: Thomas Gleixner
Date: Thu May 27 2010 - 17:41:49 EST


On Thu, 27 May 2010, Rafael J. Wysocki wrote:

> On Thursday 27 May 2010, Thomas Gleixner wrote:
> > On Thu, 27 May 2010, Alan Stern wrote:
> >
> > > On Thu, 27 May 2010, Felipe Balbi wrote:
> > >
> > > > On Thu, May 27, 2010 at 05:06:23PM +0200, ext Alan Stern wrote:
> > > > >If people don't mind, here is a greatly simplified summary of the
> > > > >comments and objections I have seen so far on this thread:
> > > > >
> > > > > The in-kernel suspend blocker implementation is okay, even
> > > > > beneficial.
> > > >
> > > > I disagree here. I believe expressing that as QoS is much better. Let
> > > > the kernel decide which power state is better as long as I can say I
> > > > need 100us IRQ latency or 100ms wakeup latency.
> > >
> > > Does this mean you believe "echo mem >/sys/power/state" is bad and
> > > should be removed? Or "echo disk >/sys/power/state"? They pay no
> >
> > mem should be replaced by an idle suspend to ram mechanism
>
> Well, what about when I want the machine to suspend _regardless_ of whether
> or not it's idle at the moment? That actually happens quite often to me. :-)

Fair enough. Let's agree on a non ambigous terminology then:

forced:

suspend which you enforce via user interaction, which
also implies that you risk losing wakeups depending on
the hardware properties

opportunistic:

suspend driven from the idle context, which guarantees to
not lose wakeups. Provided only when the hardware does
provide the necessary capabilities.

Thanks,

tglx
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/