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Date:   Sun, 09 Oct 2022 21:51:18 -0700
From:   "H. Peter Anvin" <hpa@zytor.com>
To:     "Li, Xin3" <xin3.li@intel.com>, Brian Gerst <brgerst@gmail.com>
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On October 9, 2022 9:32:34 PM PDT, "Li, Xin3" <xin3=2Eli@intel=2Ecom> wrote=
:
>> > > There are not that many call sites, so using something like this
>> > > (incorporating Peter Z's suggestion for the exception handler) woul=
d
>> > > be better from a code readability perspective vs=2E a tiny increase=
 in code size=2E
>> >
>> > The existing approach patches the binary code thus we don't need to c=
heck it
>> at runtime=2E
>>=20
>> static_cpu_has() uses alternatives to patch the branch, so there is no =
runtime
>> check after early boot=2E
>>=20
>
>Sorry, didn't know it, thanks for point it out=2E
>
>If we prefer static_cpu_has, are you asking to replace all alternative ma=
cros with it?
>
>Xin
>
>

Honestly, it seems to me to be more than a bit excessive=2E The code might=
 be nontrivial, but *with proper commenting* it should be perfectly underst=
andable=2E=2E=2E