On Fri, 18 Jun 2010, Tejun Heo wrote: > Hello, > > On 06/18/2010 08:26 AM, Arjan van de Ven wrote: > > On Thu, 17 Jun 2010 18:47:19 +0200 > > Tejun Heo <tj@xxxxxxxxxx> wrote: > > > >> > >> Hmmm... the thing is that there will be many cases which won't fit > >> irq_expect() model (why irq_watch() exists in the first place) and for > >> the time being libata is the only one providing that data. Would the > >> data still be useful to determine which c-state to use? > > > > yes absolutely. One of the hard cases right now that the C state code > > has is that it needs to predict the future. While it has a ton of > > heuristics, including some is there IO oustanding" ones, libata is a > > really good case: libata will know generally that within one seek time > > (5 msec on rotating rust, much less on floating electrons) there'll be > > an interrupt (give or take, but this is what we can do heuristics for > > on a per irq level). > > So it's a good suggestion of what the future will be like, MUCH better > > than any hint we have right now... all we have right now is some > > history, and when the next timer is.... > > Cool, good to know. It shouldn't be difficult to at all to add. Once > the whole thing gets generally agreed on, I'll work on that. > > Thomas, Ingo, through which tree should these patches routed through? I'm going to pull that into tip/genirq I guess Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
