[PATCH v3 0/8] PM / ACPI / i2c: Deploy runtime PM centric path for system sleep

Rafael J. Wysocki rjw at rjwysocki.net
Mon Sep 4 03:04:58 PDT 2017


On Monday, September 4, 2017 7:46:37 AM CEST Lukas Wunner wrote:
> On Mon, Sep 04, 2017 at 02:17:21AM +0200, Rafael J. Wysocki wrote:
> > OTOH I'm starting to think that direct_complete is only theoretically
> > useful and may not be actually set very often in practice, whereas it
> > adds significant complexity to the code, so I'm not sure about it any
> > more.
> 
> That makes me come out of the woodwork as a direct_complete fan:
> 
> Runtime resuming a discrete GPU on a modern dual GPU laptop takes about
> 1.5 sec, runtime resuming Thunderbolt controllers more than 2 sec.
> A discrete GPU easily consumes 10W, a Thunderbolt controller 2W.
> 
> So not having direct_complete would noticeably delay system suspend and
> resume as well as reduce battery life.

Well, that's a good reason for having it. :-)

Thanks,
Rafael




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