Re: [PATCH 0/2] Allow assembly code to use BIT(), GENMASK(), etc. and clean-up arm64 header

From: Will Deacon
Date: Tue Jun 11 2019 - 11:53:37 EST


On Wed, Jun 05, 2019 at 06:01:10PM +0900, Masahiro Yamada wrote:
> On Wed, Jun 5, 2019 at 4:36 PM Catalin Marinas <catalin.marinas@xxxxxxx> wrote:
> >
> > On Mon, May 27, 2019 at 05:34:10PM +0900, Masahiro Yamada wrote:
> > > Some in-kernel headers use _BITUL() instead of BIT().
> > >
> > > arch/arm64/include/asm/sysreg.h
> > > arch/s390/include/asm/*.h
> > >
> > > I think the reason is because BIT() is currently not available
> > > in assembly. It hard-codes 1UL, which is not available in assembly.
> > [...]
> > > Masahiro Yamada (2):
> > > linux/bits.h: make BIT(), GENMASK(), and friends available in assembly
> > > arm64: replace _BITUL() with BIT()
> > >
> > > arch/arm64/include/asm/sysreg.h | 82 ++++++++++++++++-----------------
> > > include/linux/bits.h | 17 ++++---
> >
> > I'm not sure it's worth the hassle. It's nice to have the same BIT macro
> > but a quick grep shows arc, arm64, s390 and x86 using _BITUL. Maybe a
> > tree-wide clean-up would be more appropriate.
>
>
> I am happy to clean-up the others
> in the next development cycle
> once 1/2 lands in the mainline.
>
>
> Since there is no subsystem that
> takes care of include/linux/bits.h,
> I just asked Will to pick up both.
> I planed per-arch patch submission
> to reduce the possibility of merge conflict.
>
>
> If you guys are not willing to pick up them,
> is it better to send treewide conversion to Andrew?

I'm happy either way, so I've acked both of the patches.

Will