From: David Stevens <stevensd@xxxxxxxxxxxx> Skip allocating gfn_track arrays when tracking of guest write access to pages is not required. For VMs where the allocation can be avoided, this saves 2 bytes per 4KB of guest memory. Write tracking is used to manage shadow page tables in three cases - when tdp is not supported, when nested virtualization is used, and for GVT-g. If tdp_enable is set and the kernel is compiled without GVT-g, then the gfn_track arrays can be allocated lazily when the shadow MMU is initialized. v1 -> v2: - lazily allocate gfn_track when shadow MMU is initialized, instead of looking at cpuid David Stevens (2): KVM: x86: add config for non-kvm users of page tracking KVM: x86: only allocate gfn_track when necessary arch/x86/include/asm/kvm_host.h | 8 ++++ arch/x86/include/asm/kvm_page_track.h | 5 +- arch/x86/kvm/Kconfig | 3 ++ arch/x86/kvm/mmu/mmu.c | 7 +++ arch/x86/kvm/mmu/page_track.c | 69 ++++++++++++++++++++++++++- arch/x86/kvm/x86.c | 2 +- drivers/gpu/drm/i915/Kconfig | 1 + 7 files changed, 91 insertions(+), 4 deletions(-) -- 2.33.0.464.g1972c5931b-goog
