Hi Gavin, On 2021/3/15 12:18, Gavin Shan wrote: > We needn't retrieve the memory slot again in user_mem_abort() because > the corresponding memory slot has been passed from the caller. This I think you are right, though fault_ipa will be adjusted when we try to use block mapping, the fault_supports_stage2_huge_mapping() makes sure we're not trying to map anything not covered by the memslot, so the adjusted fault_ipa still belongs to the memslot.
> would save some CPU cycles. For example, the time used to write 1GB > memory, which is backed by 2MB hugetlb pages and write-protected, is > dropped by 6.8% from 928ms to 864ms. > > Signed-off-by: Gavin Shan <gs...@redhat.com> > --- > arch/arm64/kvm/mmu.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c > index a5a8ade9fde4..4a4abcccfafb 100644 > --- a/arch/arm64/kvm/mmu.c > +++ b/arch/arm64/kvm/mmu.c > @@ -846,7 +846,8 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, > phys_addr_t fault_ipa, > */ > smp_rmb(); > > - pfn = gfn_to_pfn_prot(kvm, gfn, write_fault, &writable); > + pfn = __gfn_to_pfn_memslot(memslot, gfn, false, NULL, > + write_fault, &writable, NULL); It's better to update the code comments at same time. > if (pfn == KVM_PFN_ERR_HWPOISON) { > kvm_send_hwpoison_signal(hva, vma_shift); > return 0; > @@ -912,7 +913,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, > phys_addr_t fault_ipa, > /* Mark the page dirty only if the fault is handled successfully */ > if (writable && !ret) { > kvm_set_pfn_dirty(pfn); > - mark_page_dirty(kvm, gfn); > + mark_page_dirty_in_slot(kvm, memslot, gfn); > } > > out_unlock: > Thanks, Keqian. _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm