On Wed, 2021-05-26 at 19:44 +0100, Ilias Stamatis wrote: > KVM currently supports hardware-assisted TSC scaling but only for L1; > the feature is not exposed to nested guests. This patch series adds > support for nested TSC scaling and allows both L1 and L2 to be scaled > with different scaling factors. That is achieved by "merging" the 01 and > 02 values together. > > Most of the logic in this series is implemented in common code (by doing > the necessary restructurings), however the patches add support for VMX > only. Adding support for SVM should be easy at this point and Maxim > Levitsky has volunteered to do this (thanks!). > > Changelog: > > Only patch 9 needs reviewing at this point, but I am re-sending the > whole series as I also applied nitpicks suggested to some of the other > pathces. > > v4: > - Added vendor callbacks for writing the TSC multiplier > - Moved the VMCS multiplier writes from the VMCS load path to common > code that only gets called on TSC ratio changes > - Merged together patches 10 and 11 of v3 > - Applied all nitpick-feedback of the previous versions > > v3: > - Applied Sean's feedback > - Refactored patches 7 to 10 > > v2: > - Applied all of Maxim's feedback > - Added a mul_s64_u64_shr function in math64.h > - Added a separate kvm_scale_tsc_l1 function instead of passing an > argument to kvm_scale_tsc > - Implemented the 02 fields calculations in common code > - Moved all of write_l1_tsc_offset's logic to common code > - Added a check for whether the TSC is stable in patch 10 > - Used a random L1 factor and a negative offset in patch 10 > > Ilias Stamatis (11): > math64.h: Add mul_s64_u64_shr() > KVM: X86: Store L1's TSC scaling ratio in 'struct kvm_vcpu_arch' > KVM: X86: Rename kvm_compute_tsc_offset() to > kvm_compute_l1_tsc_offset() > KVM: X86: Add a ratio parameter to kvm_scale_tsc() > KVM: nVMX: Add a TSC multiplier field in VMCS12 > KVM: X86: Add functions for retrieving L2 TSC fields from common code > KVM: X86: Add functions that calculate the nested TSC fields > KVM: X86: Move write_l1_tsc_offset() logic to common code and rename > it > KVM: X86: Add vendor callbacks for writing the TSC multiplier > KVM: nVMX: Enable nested TSC scaling > KVM: selftests: x86: Add vmx_nested_tsc_scaling_test > > arch/x86/include/asm/kvm-x86-ops.h | 5 +- > arch/x86/include/asm/kvm_host.h | 15 +- > arch/x86/kvm/svm/svm.c | 35 ++- > arch/x86/kvm/vmx/nested.c | 33 ++- > arch/x86/kvm/vmx/vmcs12.c | 1 + > arch/x86/kvm/vmx/vmcs12.h | 4 +- > arch/x86/kvm/vmx/vmx.c | 55 ++-- > arch/x86/kvm/vmx/vmx.h | 11 +- > arch/x86/kvm/x86.c | 114 +++++++-- > include/linux/math64.h | 19 ++ > tools/testing/selftests/kvm/.gitignore | 1 + > tools/testing/selftests/kvm/Makefile | 1 + > .../kvm/x86_64/vmx_nested_tsc_scaling_test.c | 242 ++++++++++++++++++ > 13 files changed, 451 insertions(+), 85 deletions(-) > create mode 100644 tools/testing/selftests/kvm/x86_64/vmx_nested_tsc_scaling_test.c > Hello, What is the status of these? I think all patches have been reviewed and approved at this point. (There's a new revision v6 of patch 9 that has been reviewed too) Thanks, Ilias
