On Fri, Apr 22, 2022, David Matlack wrote:
> drop_large_spte() drops a large SPTE if it exists and then flushes TLBs.
> Its helper function, __drop_large_spte(), does the drop without the
> flush.
>
> In preparation for eager page splitting, which will need to sometimes
> flush when dropping large SPTEs (and sometimes not), push the flushing
> logic down into __drop_large_spte() and add a bool parameter to control
> it.
>
> No functional change intended.
>
> Reviewed-by: Peter Xu <peterx@xxxxxxxxxx>
> Signed-off-by: David Matlack <dmatlack@xxxxxxxxxx>
> ---
> arch/x86/kvm/mmu/mmu.c | 29 +++++++++++++++--------------
> 1 file changed, 15 insertions(+), 14 deletions(-)
>
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index 479c581e8a96..a5961c17eb36 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -1183,28 +1183,29 @@ static void drop_spte(struct kvm *kvm, u64 *sptep)
> rmap_remove(kvm, sptep);
> }
>
> -
> -static bool __drop_large_spte(struct kvm *kvm, u64 *sptep)
> +static void __drop_large_spte(struct kvm *kvm, u64 *sptep, bool flush)
> {
> - if (is_large_pte(*sptep)) {
> - WARN_ON(sptep_to_sp(sptep)->role.level == PG_LEVEL_4K);
> - drop_spte(kvm, sptep);
> - return true;
> - }
> + struct kvm_mmu_page *sp;
>
> - return false;
> -}
> + if (!is_large_pte(*sptep))
> + return;
>
> -static void drop_large_spte(struct kvm_vcpu *vcpu, u64 *sptep)
> -{
> - if (__drop_large_spte(vcpu->kvm, sptep)) {
> - struct kvm_mmu_page *sp = sptep_to_sp(sptep);
> + sp = sptep_to_sp(sptep);
> + WARN_ON(sp->role.level == PG_LEVEL_4K);
>
> - kvm_flush_remote_tlbs_with_address(vcpu->kvm, sp->gfn,
> + drop_spte(kvm, sptep);
> +
> + if (flush) {
Unnecessary curly braces.
> + kvm_flush_remote_tlbs_with_address(kvm, sp->gfn,
> KVM_PAGES_PER_HPAGE(sp->role.level));
> }
> }
>
> +static void drop_large_spte(struct kvm_vcpu *vcpu, u64 *sptep)
> +{
> + return __drop_large_spte(vcpu->kvm, sptep, true);
> +}
> +
> /*
> * Write-protect on the specified @sptep, @pt_protect indicates whether
> * spte write-protection is caused by protecting shadow page table.
> --
> 2.36.0.rc2.479.g8af0fa9b8e-goog
>
_______________________________________________
kvmarm mailing list
kvmarm@xxxxxxxxxxxxxxxxxxxxx
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
