[PATCH 11/14] vdso/vsyscall: Update auxiliary clock data in the datapage

[Arnd Bergmann]

On Mon, Jul 7, 2025, at 08:57, Thomas Gleixner wrote:
> On Tue, Jul 01 2025 at 10:58, Thomas Weißschuh wrote:
>>  
>> +#if defined(CONFIG_GENERIC_TIME_VSYSCALL) && defined(CONFIG_GENERIC_GETTIMEOFDAY) && \
>> +	defined(CONFIG_POSIX_AUX_CLOCKS)
>
> CONFIG_GENERIC_GETTIMEOFDAY requires CONFIG_GENERIC_TIME_VSYSCALL, but
> that's not expressed anywhere. This stuff has grown too many config
> options over time:
>
> GENERIC_TIME_VSYSCALL, HAVE_GENERIC_VDSO, GENERIC_VDSO_DATA_STORE
>
> All architectures except SPARC64 use the generic code and the generic
> VDSO data store implementation. That config maze wants to be
> consolidated.

Would it help to replace the custom sparc64 vdso with the
thing that parisc does and call the fallback directly?

I doubt anyone still cares about the clock_gettime() performance
on sparc64, and removing it would remove all those special cases:

 arch/sparc/Kconfig                  |   1 -
 arch/sparc/include/asm/vvar.h       |  75 --------
 arch/sparc/kernel/Makefile          |   1 -
 arch/sparc/kernel/vdso.c            |  69 --------
 arch/sparc/vdso/Makefile            |   2 +-
 arch/sparc/vdso/vclock_gettime.c    | 340 +++---------------------------------
 arch/sparc/vdso/vdso.lds.S          |   2 -
 arch/sparc/vdso/vdso32/vdso32.lds.S |   3 +-
 arch/sparc/vdso/vma.c               | 265 +---------------------------
 9 files changed, 28 insertions(+), 730 deletions(-)

(the added lines here also fix the missing clock_gettime64,
which was equally blocked on the sparc64 oddities)

      Arnd