On Mon, Apr 09, 2018 at 09:06:11AM +0200, Ingo Molnar wrote:
>
> * Ingo Molnar <mi...@kernel.org> wrote:
>
> >
> > * Dominik Brodowski <li...@dominikbrodowski.net> wrote:
> >
> > > On Sun, Apr 08, 2018 at 10:35:50AM +0200, Ingo Molnar wrote:
> > > > - _____sys_waitid() # ridiculous number of underscores?
> > > > - __sys_waitid() # too generic sounding?
> > >
> > > ... and we'd need to rename internal helpers in net/
> > >
> > > > - __inline_sys_waitid() # too long?
> > >
> > > sounds acceptable, though a bit long (especially for the compat case,
> > > though
> > > it doesn't really matter in the case of
> > > __inline_compat_sys_sched_rr_get_interval)
> >
> > So as per the previous mail this is not just an inline function, but an
> > active
> > type conversion wrapper that sign-extends 32-bit ints to longs, which is
> > important
> > on some 64-bit architectures.
> >
> > And that's a really non-obvious property IMO, and the name should probably
> > reflect
> > _that_ non-obvious property, not the inlining property which is really just
> > a
> > small detail.
> >
> > I.e. how about:
> >
> > __se_sys_waitid()
> >
> > ... where 'se' stands for sign-extended, with a comment in the macro that
> > explains
> > the prefix? (The historical abbreviation for sign extension is 'sext',
> > which I
> > think wouldn't really be suitable these days.)
>
> Ok, so I got confused there: I think it's the do_sys_waitid() intermediate
> that
> is actually doing the sign-extension - and the inlined helper is what is in
> the
> syscall definition body.
>
> So it's all still somewhat of a confusing misnomer: the 'do' named function
> is
> actually the sign-extension function variant - and the '_il' variant actually
> 'does' the real work ...
>
> I.e., old naming:
>
> 810f08d0 t kernel_waitid # common C function (see kernel/exit.c)
>
> <inline> __il_sys_waitid # inlined helper doing the actual work
> # (takes parameters as declared)
>
> 810f1aa0 T __do_sys_waitid # C function calling inlined helper
> # (takes parameters of type long; casts
> # them to the declared type)
>
> 810f1aa0 T sys_waitid # alias to __do_sys_waitid() (taking
> # parameters as declared), to be included
> # in syscall table
>
>
> New suggested naming:
>
> 810f08d0 t kernel_waitid # common C function (see kernel/exit.c)
>
> <inline> __do_sys_waitid # inlined helper doing the actual work
> # (takes original parameters as declared)
>
> 810f1aa0 T __se_sys_waitid # sign-extending C function calling inlined
> # helper (takes parameters of type long;
> # casts them to the declared type)
>
> 810f1aa0 T sys_waitid # alias to __se_sys_waitid() (but taking
> # original parameters as declared), to be
> # included in syscall table
>
> Agreed?
Yes.
Thanks,
Dominik
