lkml.org 
[lkml]   [2018]   [Sep]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH net-next v3 01/17] asm: simd context helper API
On Wed, Sep 12, 2018 at 08:10:41PM +0200, Jason A. Donenfeld wrote:
> On Wed, Sep 12, 2018 at 8:14 AM Kevin Easton <kevin@guarana.org> wrote:
> > Given that it's always supposed to be used like that, mightn't it be
> > better if simd_relax() took a pointer to the context, so the call is
> > just
> >
> > simd_relax(&simd_context);
> >
> > ?
> >
> > The inlining means that there won't actually be a pointer dereference in
> > the emitted code.
> >
> > If simd_put() also took a pointer then it could set the context back to
> > HAVE_NO_SIMD as well?
>
> That's sort of a neat idea. I guess in this scheme, you'd envision:
>
> simd_context_t simd_context;
>
> simd_get(&simd_context);
> simd_relax(&simd_context);
> simd_put(&simd_context);
>
> And this way, if simd_context ever becomes a heavier struct, it can be
> modified in place rather than returned by value from the function. On
> the other hand, it's a little bit more annoying to type and makes it
> harder to do declaration and initialization on the same line.

Yes. It's also how most get/put APIs already work in the kernel, eg
kref_get/put (mostly because they tend to be 'getting/putting' an
already-initialized object, though).

- Kevin

\
 
 \ /
  Last update: 2018-09-13 07:03    [W:0.116 / U:0.944 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site