Re: [PATCH] sysv: linux: Pass 64-bit version of semctl syscall

[Arnd Bergmann <arnd at arndb dot de>]

On Sat, Feb 1, 2020 at 12:59 AM Alistair Francis <alistair23@gmail.com> wrote:
>
> On Fri, Jan 31, 2020 at 1:54 PM Arnd Bergmann <arnd@arndb.de> wrote:
> >
> > On Fri, Jan 31, 2020 at 6:11 PM Alistair Francis
> > <alistair.francis@wdc.com> wrote:
> > >
> > > Adjust the semctl syscall to match what the kernel expects. That is pass
> > > a version with a *_high version of sem_otime and sem_ctime in the order
> > > that the kernel expects.
> >
> > > +# ifdef __SEMID_DS_HIGH
> > > +#  if defined (__SEMID_DS_HIGH_END)
> > ...
> > > +#  elif defined (__SEMID_DS_HIGH_SWAP)
> >
> > The three new macros you check for here directly correspond to the
> > possible combinations of the existing __SEM_PAD_AFTER_TIME
> > and __SEM_PAD_BEFORE_TIME macros, right?
>
> Hey Arnd,
>
> I think you are asking why we don't just use the existing macros
> instead of adding more (and keep the core logic as is). Besides the
> naming being confusing then, they two types don't line up. For
> example:
>
> PowerPC has this:
>
>  #define __SEM_PAD_AFTER_TIME 0
>  #define __SEM_PAD_BEFORE_TIME (__TIMESIZE == 32)
> +#define __SEMID_DS_HIGH (__WORDSIZE == 32)
> +#define __SEMID_DS_HIGH_SWAP (__WORDSIZE == 32)
>
> while HPPA has this:
>
>  #define __SEM_PAD_AFTER_TIME 0
>  #define __SEM_PAD_BEFORE_TIME (__TIMESIZE == 32)
> +#define __SEMID_DS_HIGH (__WORDSIZE == 32)
>
> They have different __SEMID_DS macros, but the same __SEM_PAD macros.

If they don't line up, that probably means that one of them is wrong ;-)

It looks like the HPPA version to also define __SEMID_DS_HIGH_SWAP.

       Arnd