Re: [PATCH 0/3] Move the ARCH_DMA_MINALIGN definition to asm/cache.h

Catalin Marinas
2023-06-13T19:49:31Z

On Tue, Jun 13, 2023 at 04:42:40PM +0000, Christophe Leroy wrote:
>
>
> Le 13/06/2023 à 17:52, Catalin Marinas a écrit :
> > Hi,
> >
> > The ARCH_KMALLOC_MINALIGN reduction series defines a generic
> > ARCH_DMA_MINALIGN in linux/cache.h:
> >
> > https://lore.kernel.org/r/20230612153201.554742-2-catalin.marinas@arm.com/
> >
> > Unfortunately, this causes a duplicate definition warning for
> > microblaze, powerpc (32-bit only) and sh as these architectures define
> > ARCH_DMA_MINALIGN in a different file than asm/cache.h. Move the macro
> > to asm/cache.h to avoid this issue and also bring them in line with the
> > other architectures.
>
> What about mips ?
>
> arch/mips/include/asm/mach-generic/kmalloc.h:#define ARCH_DMA_MINALIGN 128
> arch/mips/include/asm/mach-ip32/kmalloc.h:#define ARCH_DMA_MINALIGN 32
> arch/mips/include/asm/mach-ip32/kmalloc.h:#define ARCH_DMA_MINALIGN 128
> arch/mips/include/asm/mach-n64/kmalloc.h:#define ARCH_DMA_MINALIGN L1_CACHE_BYTES
> arch/mips/include/asm/mach-tx49xx/kmalloc.h:#define ARCH_DMA_MINALIGN L1_CACHE_BYTES

Sorry, I should have mentioned it in the cover letter (discussed here -
https://lore.kernel.org/r/ZIhPaixb%2F0ve7zZo@arm.com/). These kmalloc.h
files are included in asm/cache.h, based on which machine is enabled, so
there's no problem for mips. It makes more sense to keep them in those
mach-*/kmalloc.h files instead of having lots of #ifdefs in cache.h.

--
Catalin