Re: [PATCH -mm] mm: Unify pte_to_pgoff and pgoff_to_pte helpers

From: Ingo Molnar
Date: Wed Aug 14 2013 - 05:50:26 EST



* Cyrill Gorcunov <gorcunov@xxxxxxxxx> wrote:

> On Wed, Aug 14, 2013 at 01:08:56AM -0700, Andrew Morton wrote:
> > >
> > > > Can it be written in C with types and proper variable names and such
> > > > radical stuff?
> > >
> > > Could you elaborate? You mean inline helper or macro with type checks?
> >
> > /*
> > * description goes here
> > */
> > static inline pteval_t pte_bfop(pteval_t val, int rightshift, ...)
> > {
> > ...
> > }
> >
> > So much better! We really should only implement code in a macro if it
> > *has* to be done as a macro and I don't think that's the case here?
>
> Well, I'll have to check if it really doesn't generate additional
> instructions in generated code, since it's hotpath. I'll ping back once
> things are done.

An __always_inline should never do that.

Thanks,

Ingo
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