On Wed, Nov 29, 2023 at 03:29:05PM -0600, Nathan Bossart wrote:
> I haven't done any sort of performance testing on this yet. Some
> preliminary web searches suggest that there is unlikely to be much
> difference between cmpxchg and xchg, but presumably there's some difference
> between xchg and doing cmpxchg in a while loop (as is done in
> atomics/generic.h today). I'll report back once I've had a chance to do
> some testing...
Some rudimentary tests show a >40% speedup with this patch on x86_64.
--
Nathan Bossart
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