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From: Richard Henderson <rth@twiddle.net>
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Date: Sun, 9 Jul 2017 10:43:12 -1000
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Subject: Re: [Qemu-devel] [PATCH 16/22] tcg: keep a list of TCGContext's
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To: "Emilio G. Cota" <cota@braap.org>, qemu-devel@nongnu.org

On 07/08/2017 09:50 PM, Emilio G. Cota wrote:
> Before we make TCGContext thread-local. Once that is done, iterating
> over all TCG contexts will be quite useful; for instance we
> will need it to gather profiling info from each TCGContext.
> 
> A possible alternative would be to keep an array of TCGContext pointers.
> However this option however is not that trivial, because vCPUs are spawned in
> parallel. So let's just keep it simple and use a list protected by a lock.

Do we not know the number of cpus?  I would have thought that we did, via -smp. 
  Even cpu-hotplug would still have some sort of bounds?

Which really suggests an array would be better.


r~