Messages in this thread | | | Date | Sun, 13 Jul 2008 01:19:09 +0200 | From | "Dmitry Adamushko" <> | Subject | Re: current linux-2.6.git: cpusets completely broken |
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2008/7/13 Linus Torvalds <torvalds@linux-foundation.org>: > >> (A little pet horse for the occasion: Testing can show the presence of >> errors, but not their absence. But that's a different story.) > > Absolutely. Which is actually why I prefer my patch. I think it fixes - in > general - the issue of CPU migration migrating tasks back to the CPU that > we're taking down. > > The other patches seem to work around just the problem that _triggers_ the > bug. They don't actually make it impossible to migrate to a CPU that is > getting shut down - they just try to avoid the particular sequence that > made it happen for you.
Well, they try to make sched-domains consistent for all possible cases, not just any particular case. So no, they don't allow a possibility to leave tasks on a dead CPU (unless there is another bug).
With your patch (and a cpusets :: hotplug handler from the current -git) sched-domains are still broken and they are used in a number of places. So why keep them at all?
I'm really surprised that Vegard says this "cpu_active_map" patch alone fixes the problem.
With your modifications of common_cpu_mem_hotplug_unplug() - yes but then it will work even without "cpu_active_map".
(ok, unless I'm really blind at this late hour so please direct me to the right way :-)
> > Linus >
-- Best regards, Dmitry Adamushko
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