On Mon, 03 May 2010 09:40:11 -0700 Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx> wrote: > > One question, though... one clear use of this API is for drivers to > > say "don't go into C3 or deeper because things go wrong"; I'm about to > > add another one of those. It works, but the use of a > > PM_QOS_CPU_DMA_LATENCY requirement with a hard-coded number that one > > hopes is small enough seems a bit...indirect. I wonder if it would be > > clearer and more robust to add a new requirement^Wrequest type saying > > "the quality of service I need is shallow sleeps only"? > > The problem with that is portability. > > What does "shallow" mean? Well, shallow could mean that the state lacks the CPUIDLE_FLAG_DEEP flag; that should be relatively portable. In any case, it seems more so than "if I put in a 55us latency requirement, I'll stay out of C3". Just a thought, anyway; it's not like I've really worked through a plausible alternative API. jon _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
