Re: [Patch v3 8/9] KVM: x86/mmu: Make split_shadow_page_cache NUMA aware

[David Matlack <dmatlack@google.com>]

On Wed, Dec 21, 2022 at 06:34:56PM -0800, Vipin Sharma wrote:
> Make split_shadow_page_cache NUMA aware and allocate page table's pages
> during the split based on the underlying physical page's NUMA node.
> 
> Signed-off-by: Vipin Sharma <vipinsh@google.com>
> ---
>  arch/x86/include/asm/kvm_host.h |  2 +-
>  arch/x86/kvm/mmu/mmu.c          | 50 ++++++++++++++++++---------------
>  2 files changed, 29 insertions(+), 23 deletions(-)
> 
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index b1f319ad6f89..7b3f36ae37a4 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -1410,7 +1410,7 @@ struct kvm_arch {
>  	 *
>  	 * Protected by kvm->slots_lock.
>  	 */
> -	struct kvm_mmu_memory_cache split_shadow_page_cache;
> +	struct kvm_mmu_memory_cache split_shadow_page_cache[MAX_NUMNODES];
>  	struct kvm_mmu_memory_cache split_page_header_cache;
>  
>  	/*
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index 511c6ef265ee..7454bfc49a51 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -6126,7 +6126,7 @@ static void kvm_mmu_invalidate_zap_pages_in_memslot(struct kvm *kvm,
>  int kvm_mmu_init_vm(struct kvm *kvm)
>  {
>  	struct kvm_page_track_notifier_node *node = &kvm->arch.mmu_sp_tracker;
> -	int r;
> +	int r, nid;
>  
>  	INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
>  	INIT_LIST_HEAD(&kvm->arch.possible_nx_huge_pages);
> @@ -6145,8 +6145,9 @@ int kvm_mmu_init_vm(struct kvm *kvm)
>  	INIT_KVM_MMU_MEMORY_CACHE(&kvm->arch.split_page_header_cache,
>  				  mmu_page_header_cache, NUMA_NO_NODE);
>  
> -	INIT_KVM_MMU_MEMORY_CACHE(&kvm->arch.split_shadow_page_cache,
> -				  NULL, NUMA_NO_NODE);
> +	for_each_node(nid)
> +		INIT_KVM_MMU_MEMORY_CACHE(&kvm->arch.split_shadow_page_cache[nid],
> +					  NULL, NUMA_NO_NODE);
                                                ^^^^^^^^^^^^
						Should this be nid?