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From: Richard Henderson <rth@twiddle.net>
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Date: Wed, 18 May 2016 09:02:37 -0700
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Subject: Re: [Qemu-devel] [PATCH v5 07/18] qemu-thread: add simple
 test-and-set spinlock
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To: Peter Maydell <peter.maydell@linaro.org>, Sergey Fedorov <serge.fdrv@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>, "Emilio G. Cota" <cota@braap.org>, QEMU Developers <qemu-devel@nongnu.org>, MTTCG Devel <mttcg@greensocs.com>, =?UTF-8?Q?Alex_Benn=c3=a9e?= <alex.bennee@linaro.org>, Peter Crosthwaite <crosthwaite.peter@gmail.com>

On 05/18/2016 08:35 AM, Peter Maydell wrote:
> (v7 probably gets compiled the same way as v6 here, though.)

The meaningful difference in v7 is ldrexb, which goes to the byte semantics of 
__atomic_test_and_set, which is how this digression got started.


r~