On Tue, May 17, 2022 at 07:05:15PM +0000, David Matlack wrote:
> x86_page_size is an enum used to communicate the desired page size with
> which to map a range of memory. Under the hood they just encode the
> desired level at which to map the page. This ends up being clunky in a
> few ways:
>
> - The name suggests it encodes the size of the page rather than the
> level.
> - In other places in x86_64/processor.c we just use a raw int to encode
> the level.
>
> Simplify this by adopting the kernel style of PG_LEVEL_XX enums and pass
> around raw ints when referring to the level. This makes the code easier
> to understand since these macros are very common in KVM MMU code.
>
> Signed-off-by: David Matlack <dmatlack@xxxxxxxxxx>
> ---
> .../selftests/kvm/include/x86_64/processor.h | 18 ++++++----
> .../selftests/kvm/lib/x86_64/processor.c | 33 ++++++++++---------
> .../selftests/kvm/max_guest_memory_test.c | 2 +-
> .../selftests/kvm/x86_64/mmu_role_test.c | 2 +-
> 4 files changed, 31 insertions(+), 24 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
> index 37db341d4cc5..434a4f60f4d9 100644
> --- a/tools/testing/selftests/kvm/include/x86_64/processor.h
> +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
> @@ -465,13 +465,19 @@ void vcpu_set_hv_cpuid(struct kvm_vm *vm, uint32_t vcpuid);
> struct kvm_cpuid2 *vcpu_get_supported_hv_cpuid(struct kvm_vm *vm, uint32_t vcpuid);
> void vm_xsave_req_perm(int bit);
>
> -enum x86_page_size {
> - X86_PAGE_SIZE_4K = 0,
> - X86_PAGE_SIZE_2M,
> - X86_PAGE_SIZE_1G,
> +enum pg_level {
> + PG_LEVEL_NONE,
> + PG_LEVEL_4K,
> + PG_LEVEL_2M,
> + PG_LEVEL_1G,
> + PG_LEVEL_512G,
> + PG_LEVEL_NUM
> };
I still prefer PTE/PMD/PUD/... as I suggested, as that's how the kernel mm
handles these levels with arch-independent way across the kernel. But
well.. I never fight hard on namings, because I know that's the major
complexity. :-)
Reviewed-by: Peter Xu <peterx@xxxxxxxxxx>
--
Peter Xu
