Re: [PATCH] block: blk-iocost: fix build for ARCH with missing local64.h files

[Peter Zijlstra]

On Wed, Dec 09, 2020 at 10:16:20PM -0800, Randy Dunlap wrote:
> On 12/9/20 10:07 PM, Christoph Hellwig wrote:
> > On Wed, Dec 09, 2020 at 12:46:57PM -0800, Randy Dunlap wrote:
> >> When building block/blk-iocost.c on arch/x6x/ or arch/nios2/, the
> >> build fails due to missing the <asm/local64.h> file.
> > 
> > Please mark it mandatory-y if the asm-generic version is suitable
> > for everyone and random pieces of kernel code are supposed to include
> > it.
> 
> include/asm-generic/local64.h has comments about some $arch could do
> its things better/faster instead of using asm-generic, but no $arch has
> done that since 2010 when it was added.

Yeah, it's only 32bit archs, and of those I'm only sure i386 could do it
better, very maybe arm-v7. But nobody cares enough to make it happen.

All the 64bit archs are already good, because local_t is long and
local64_t defaults to local_t.