Re: [PATCH V2] include: linux: Regularise the use of FIELD_SIZEOF macro

From: Joe Perches
Date: Sat Jun 29 2019 - 12:45:46 EST


On Sat, 2019-06-29 at 17:25 +0300, Alexey Dobriyan wrote:
> On Tue, Jun 11, 2019 at 03:00:10PM -0600, Andreas Dilger wrote:
> > On Jun 11, 2019, at 2:48 PM, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
> > > On Wed, 12 Jun 2019 01:08:36 +0530 Shyam Saini <shyam.saini@xxxxxxxxxxxxxxxxxxxx> wrote:
> > I did a check, and FIELD_SIZEOF() is used about 350x, while sizeof_field()
> > is about 30x, and SIZEOF_FIELD() is only about 5x.
> >
> > That said, I'm much more in favour of "sizeof_field()" or "sizeof_member()"
> > than FIELD_SIZEOF(). Not only does that better match "offsetof()", with
> > which it is closely related, but is also closer to the original "sizeof()".
> >
> > Since this is a rather trivial change, it can be split into a number of
> > patches to get approval/landing via subsystem maintainers, and there is no
> > huge urgency to remove the original macros until the users are gone. It
> > would make sense to remove SIZEOF_FIELD() and sizeof_field() quickly so
> > they don't gain more users, and the remaining FIELD_SIZEOF() users can be
> > whittled away as the patches come through the maintainer trees.
>
> The signature should be
>
> sizeof_member(T, m)
>
> it is proper English,
> it is lowercase, so is easier to type,
> it uses standard term (member, not field),
> it blends in with standard "sizeof" operator,

yes please.

Also, a simple script conversion applied
immediately after an rc1 might be easiest
rather than individual patches.