On Wed, Aug 25, 2021 at 6:41 AM Johannes Berg [off-list ref] wrote:

On Wed, 2021-08-25 at 06:36 -0700, Dan Williams wrote:

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The problem here is that cpuid_eax() and cpuid_ebx() don't even exist on

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It can't compile because the arch dependencies are not stubbed out
like other arch specific helpers. I think this is something to revisit
if / when concepts similar to the "enqcmd" instruction appear on other
archs.

I think you're confusing ioat and idxd? :)

Whoops, indeed I am, sorry for that noise.

The ioat driver (which this patch is against) uses cpuid_eax() and
cpuid_ebx() above, and really if a driver uses that then it can only
possibly run on IA :)

True.

I'm not sure it makes sense to abstract out things such as
dca_enabled_in_bios() to a general architecture thing either?

Not general arch in this case, but a preference to keep x86'isms out
of drivers. That helper can move behind some local header ifdef'ery
and return false when needed. That said IOAT is mature, Vinod has
already taken this as is, and the commit that added it pre-dated
CONFIG_COMPILE_TEST by 6 years, so it can be forgiven.