Messages in this thread | | | Date | Fri, 25 Aug 2017 10:31:00 +0900 | From | Byungchul Park <> | Subject | Re: [PATCH v10 2/2] sched/rt: Add support for SD_PREFER_SIBLING on find_lowest_rq() |
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On Thu, Aug 24, 2017 at 09:55:14AM -0400, Steven Rostedt wrote: > On Thu, 24 Aug 2017 10:06:03 +0900 > Byungchul Park <byungchul.park@lge.com> wrote: > > > Hello Steven, > > > > Can I keep your reviewed-by with comments modified? > > Yes, but I have one nit. > > > > @@ -1668,9 +1691,35 @@ static int find_lowest_rq(struct task_struct *task) > > return this_cpu; > > } > > > > - best_cpu = cpumask_first_and(lowest_mask, > > - sched_domain_span(sd)); > > + /* > > + * If a cpu being in lowest_mask & current sd & > > + * ~prefer sd is valid, that becomes our choice. > > I can't parse the above sentence.
I might have simplified the comment too much.
~prefer means we want to exclude the domain span having SD_PREFER_SIBLING, since they should be considered as fallback candidates.
W/o ~prefer, a cpu in the domain might be chosen when we consider higher domain than the domain having SD_PREFER_SIBLING, as the best cpu, not fallback.
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