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Subject: Re: [PATCH 3/20] powerpc/mm: Add HW threads support to no_hash TLB
	management
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
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Date: Tue, 04 Aug 2009 17:22:36 +1000
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On Mon, 2009-08-03 at 12:57 -0500, Dave Kleikamp wrote:
> > cpu_last_thread_in_core(cpu) is a moving target.  You want something
> > like:
> > 
> > cpu = cpu_first_thread_in_core(cpu);
> > last = cpu_last_thread_in_core(cpu);
> > while (cpu <= last) {
> >       __clear_bit(id, stale_map[cpu]);
> >       cpu++;
> > }
> 
> Or, keeping the for loop:
> 
> for (cpu = cpu_first_thread_in_core(cpu), last =
> cpu_last_thread_in_core(cpu);
>      cpu <= last; cpu++)
>         cpu++;

Yeah, whatever form is good, I had a brain fart and didn't "see" that in
the end of loop, cpu would have actually crossed the boundary to the
next core and so cpu_last_thread_in_core() would change. Just some short
circuit in a neuron somewhere.

Cheers,
Ben.