On 06/19/2014 11:02 AM, H. Peter Anvin wrote: > On 06/18/2014 09:25 AM, Dave Hansen wrote: >> How about something like the attached patch? >> >> This lets us use static_cpu_has() for the checks, and allows us to >> easily add new checks for other features that might be compile-time >> disabled. > > Hmm... I would like something similar to required-features.h which > reflect features which *cannot* be enabled or will always be ignored; we > actually already have a handful of those
Could you elaborate a bit? I'll try and include them in the approach to make sure it works broadly. Is there a benefit to the required-features.h approach that's missing from mine? I _believe_ all of the compiler optimization around __builtin_constant_p() continues to work with the inline function instead of the #defines and bitmasks. I think the inline function approach is a bit easier to work with. Could the required-features.h approach just be from a time before __builtin_constant_p() worked well across inlines? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
