Messages in this thread | | | Date | Tue, 12 Jul 2016 15:26:13 +0100 | From | Morten Rasmussen <> | Subject | Re: [PATCH v2 05/13] sched: Enable SD_BALANCE_WAKE for asymmetric capacity systems |
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On Mon, Jul 11, 2016 at 01:24:04PM +0200, Peter Zijlstra wrote: > On Mon, Jul 11, 2016 at 12:04:58PM +0100, Morten Rasmussen wrote: > > > One alternative to setting ASYM_CAP bottom up would be to set it only > > where the asymmetry can be observed, and instead come up with a more > > complicated way of setting BALANCE_WAKE bottom up until and including > > the first level having the ASYM_CAP. > > Right, that is what I was thinking. > > > I looked at it briefly an realized that I couldn't find a clean way of > > implementing it as I don't think we have visibility of which flags that > > will be set at higher levels in the sched_domain hierarchy when the > > lower levels are initialized. IOW, we have behavioural flags settings > > depend on topology flags settings at a different level. > > Looks doable if we pass @child into sd_init() in build_sched_domain(). > Then we could simply do: > > *sd = (struct sched_domain){ > /* ... */ > .child = child, > }; > > if (sd->flags & ASYM_CAP) { > struct sched_domain *t = sd; > while (t) { > t->sd_flags |= BALANCE_WAKE; > t = t->child; > } > } > > Or something like that.
It appears to be working fine. I will roll it into v3 along with the simpler and more sane ASYM_CAP semantics :)
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