Messages in this thread | | | Subject | Re: WARNING: at arch/x86/kernel/smpboot.c:310 topology_sane.clone.1+0x6e/0x81() | From | Peter Zijlstra <> | Date | Tue, 29 May 2012 19:25:19 +0200 |
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On Tue, 2012-05-29 at 19:13 +0200, Borislav Petkov wrote: > > > As it stands I think we should discuss the definition for the generic > > topology bits (drivers/base/topology.c), because I think your > > Magny-Cours thing does the wrong thing here. > > "wrong" is such a strong word :-) Please elaborate and I'll have a look.
Right, so I meant LLC is the useful mask, and in my mind LLC is what makes a multi-core, without shared cache its just SMP. So core_siblings to me would mean LLC sharing cores.
But its all very subjective I guess, but using strong words gets the discussion going better ;-)
> > The core span in a phys_id is all nice and such, but what does it mean? > > AFAICT, this is the physical package id to which the cores belong, i.e. > physical socket. > > > IOW what would you do with it? > > Shoot empty cans with it... :-)
Right, I actually came up with proper use-case, physical hotplug :-)
Its not immediately obvious the sysfs topo bits have the llc mask, which is the more 'useful' one IMO.
Another funny case I don't see represented well is where there's multiple sockets to a node -- I know this is like ancient tech and unlikely in these days of multi-node sockets, but still ;-)
I guess what I'm asking is what is the purpose of the sys topo bits?
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