On Fri, Jul 08, 2022 at 09:18:03AM +0200, Peter Zijlstra wrote:
> Scattered across the archs are 3 basic forms of tlb_{start,end}_vma().
> Provide two new MMU_GATHER_knobs to enumerate them and remove the per
> arch tlb_{start,end}_vma() implementations.
>
> - MMU_GATHER_NO_FLUSH_CACHE indicates the arch has flush_cache_range()
> but does *NOT* want to call it for each VMA.
>
> - MMU_GATHER_MERGE_VMAS indicates the arch wants to merge the
> invalidate across multiple VMAs if possible.
>
> With these it is possible to capture the three forms:
>
> 1) empty stubs;
> select MMU_GATHER_NO_FLUSH_CACHE and MMU_GATHER_MERGE_VMAS
>
> 2) start: flush_cache_range(), end: empty;
> select MMU_GATHER_MERGE_VMAS
>
> 3) start: flush_cache_range(), end: flush_tlb_range();
> default
>
> Obviously, if the architecture does not have flush_cache_range() then
> it also doesn't need to select MMU_GATHER_NO_FLUSH_CACHE.
>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> ---
> arch/Kconfig | 7 +++++++
> arch/csky/include/asm/tlb.h | 13 -------------
> arch/loongarch/Kconfig | 1 +
> arch/loongarch/include/asm/tlb.h | 10 ----------
> arch/powerpc/Kconfig | 1 +
> arch/powerpc/include/asm/tlb.h | 2 --
> arch/s390/Kconfig | 1 +
> arch/s390/include/asm/tlb.h | 3 ---
> arch/sparc/Kconfig | 2 ++
> arch/sparc/include/asm/tlb_64.h | 2 --
> arch/x86/Kconfig | 1 +
> arch/x86/include/asm/tlb.h | 3 ---
> include/asm-generic/tlb.h | 21 +++++++++++++++++++--
> 13 files changed, 32 insertions(+), 35 deletions(-)
>
> --- a/arch/Kconfig
> +++ b/arch/Kconfig
> @@ -438,6 +438,13 @@ config MMU_GATHER_PAGE_SIZE
>
> config MMU_GATHER_NO_RANGE
> bool
> + select MMU_GATHER_MERGE_VMAS
> +
> +config MMU_GATHER_NO_FLUSH_CACHE
> + bool
If this is really a sparc-special and we don't necessarily want it to
proliferate, then maybe:
default y
depends on SPARC
would keep it confined?
But I don't mind either way and the important bits of the patch look good:
Acked-by: Will Deacon <will@xxxxxxxxxx>
Thanks,
Will
