Re: [PATCH] x86: Optimise x86 IP checksum code

[Peter Zijlstra]

On Tue, Dec 03, 2019 at 11:52:09AM +0000, David Laight wrote:

> I did get about 12 bytes/clock using adox/adcx but that would need run-time
> patching and some AMD cpu that support the instructions run them very slowly.

Isn't that was we have alternative_call() for?