Re: [PATCH 2/6] typesafe: kthread_create and kthread_run

["Bert Wesarg" <bert.wesarg@googlemail.com>]

On Jan 20, 2008 5:24 PM, Johannes Weiner <hannes@saeurebad.de> wrote:
> Hi,
>
> "Bert Wesarg" <bert.wesarg@googlemail.com> writes:
>
> > On Jan 20, 2008 12:25 PM, Jan Engelhardt <jengelh@computergmbh.de> wrote:
> >>
> >> On Jan 20 2008 20:48, Rusty Russell wrote:
> >> >+ */
> >> >+#define kthread_create(threadfn, data, namefmt...) ({         \
> >> >+      int (*_threadfn)(typeof(data)) = (threadfn);            \
> >> >+      __kthread_create((void *)_threadfn, (data), namefmt);   \
> >> >+})
> >>
> >> If you have namefmt... you need that varagrs cpp trick. IIRC:
> >>
> >>         __kthread_create((void *)_threadfn, (data), namefmt, __VA_ARGS__);
> > almost
> >
> > either:
> >
> > #define kthread_create(threadfn, data, ...) ({         \
> >         __kthread_create((void *)_threadfn, (data), __VA_ARGS__);
> >
>
> No.  This is bad because it gives the impression that it takes only two
> essential arguments which is not the case.
Right, I just forget to mention this in a comment.
>
> > or:
> >
> > #define kthread_create(threadfn, data, namefmt, ...) ({         \
> >         __kthread_create((void *)_threadfn, (data), namefmt, ##__VA_ARGS__);
> >
>
> This is better.  I prefer naming the rest args instead of using __VA_ARGS__:
>
> #define kthread_create(threadfn, data, namefmt, fmtargs...) ({ \
>         ... \
>         __kthread_create((void *)_threadfn, (data), namefmt, ## fmtargs) \
> })
>
> but I think that is just a matter of taste.
No, it is a matter of conforming to C99 or to GNU extensions.

Bert
>
>         Hannes
>