| Message ID | 20210210230625.550939-6-seanjc@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | VM: selftests: Hugepage fixes and cleanups | expand |
On Wed, Feb 10, 2021 at 3:06 PM Sean Christopherson <seanjc@google.com> wrote: > > Assert that the GPA for a memslot backed by a hugepage is 1gb aligned, > and fix perf_test_util accordingly. Lack of GPA alignment prevents KVM > from backing the guest with hugepages, e.g. x86's write-protection of > hugepages when dirty logging is activated is otherwise not exercised. > > Add a comment explaining that guest_page_size is for non-huge pages to > try and avoid confusion about what it actually tracks. > > Cc: Ben Gardon <bgardon@google.com> > Cc: Yanan Wang <wangyanan55@huawei.com> > Cc: Andrew Jones <drjones@redhat.com> > Cc: Peter Xu <peterx@redhat.com> > Cc: Aaron Lewis <aaronlewis@google.com> > Signed-off-by: Sean Christopherson <seanjc@google.com> > --- > tools/testing/selftests/kvm/lib/kvm_util.c | 2 ++ > tools/testing/selftests/kvm/lib/perf_test_util.c | 9 +++++++++ > 2 files changed, 11 insertions(+) > > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c > index 2e497fbab6ae..855d20784ba7 100644 > --- a/tools/testing/selftests/kvm/lib/kvm_util.c > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c > @@ -735,6 +735,8 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm, > else > ASSERT_EQ(src_type, VM_MEM_SRC_ANONYMOUS); > > + ASSERT_EQ(guest_paddr, align(guest_paddr, alignment)); > + > /* Add enough memory to align up if necessary */ > if (alignment > 1) > region->mmap_size += alignment; > diff --git a/tools/testing/selftests/kvm/lib/perf_test_util.c b/tools/testing/selftests/kvm/lib/perf_test_util.c > index 81490b9b4e32..f187b86f2e14 100644 > --- a/tools/testing/selftests/kvm/lib/perf_test_util.c > +++ b/tools/testing/selftests/kvm/lib/perf_test_util.c > @@ -58,6 +58,11 @@ struct kvm_vm *perf_test_create_vm(enum vm_guest_mode mode, int vcpus, > pr_info("Testing guest mode: %s\n", vm_guest_mode_string(mode)); > > perf_test_args.host_page_size = getpagesize(); > + > + /* > + * Snapshot the non-huge page size. This is used by the guest code to > + * access/dirty pages at the logging granularity. > + */ > perf_test_args.guest_page_size = vm_guest_mode_params[mode].page_size; > > guest_num_pages = vm_adjust_num_guest_pages(mode, > @@ -87,6 +92,10 @@ struct kvm_vm *perf_test_create_vm(enum vm_guest_mode mode, int vcpus, > guest_test_phys_mem = (vm_get_max_gfn(vm) - guest_num_pages) * > perf_test_args.guest_page_size; > guest_test_phys_mem &= ~(perf_test_args.host_page_size - 1); > + if (backing_src == VM_MEM_SRC_ANONYMOUS_THP || > + backing_src == VM_MEM_SRC_ANONYMOUS_HUGETLB) > + guest_test_phys_mem &= ~(KVM_UTIL_HUGEPAGE_ALIGNMENT - 1); You could use the align helper here as well. That would make this a little easier for me to read. > + > #ifdef __s390x__ > /* Align to 1M (segment size) */ > guest_test_phys_mem &= ~((1 << 20) - 1); > -- > 2.30.0.478.g8a0d178c01-goog >
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index 2e497fbab6ae..855d20784ba7 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -735,6 +735,8 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm, else ASSERT_EQ(src_type, VM_MEM_SRC_ANONYMOUS); + ASSERT_EQ(guest_paddr, align(guest_paddr, alignment)); + /* Add enough memory to align up if necessary */ if (alignment > 1) region->mmap_size += alignment; diff --git a/tools/testing/selftests/kvm/lib/perf_test_util.c b/tools/testing/selftests/kvm/lib/perf_test_util.c index 81490b9b4e32..f187b86f2e14 100644 --- a/tools/testing/selftests/kvm/lib/perf_test_util.c +++ b/tools/testing/selftests/kvm/lib/perf_test_util.c @@ -58,6 +58,11 @@ struct kvm_vm *perf_test_create_vm(enum vm_guest_mode mode, int vcpus, pr_info("Testing guest mode: %s\n", vm_guest_mode_string(mode)); perf_test_args.host_page_size = getpagesize(); + + /* + * Snapshot the non-huge page size. This is used by the guest code to + * access/dirty pages at the logging granularity. + */ perf_test_args.guest_page_size = vm_guest_mode_params[mode].page_size; guest_num_pages = vm_adjust_num_guest_pages(mode, @@ -87,6 +92,10 @@ struct kvm_vm *perf_test_create_vm(enum vm_guest_mode mode, int vcpus, guest_test_phys_mem = (vm_get_max_gfn(vm) - guest_num_pages) * perf_test_args.guest_page_size; guest_test_phys_mem &= ~(perf_test_args.host_page_size - 1); + if (backing_src == VM_MEM_SRC_ANONYMOUS_THP || + backing_src == VM_MEM_SRC_ANONYMOUS_HUGETLB) + guest_test_phys_mem &= ~(KVM_UTIL_HUGEPAGE_ALIGNMENT - 1); + #ifdef __s390x__ /* Align to 1M (segment size) */ guest_test_phys_mem &= ~((1 << 20) - 1);
Assert that the GPA for a memslot backed by a hugepage is 1gb aligned, and fix perf_test_util accordingly. Lack of GPA alignment prevents KVM from backing the guest with hugepages, e.g. x86's write-protection of hugepages when dirty logging is activated is otherwise not exercised. Add a comment explaining that guest_page_size is for non-huge pages to try and avoid confusion about what it actually tracks. Cc: Ben Gardon <bgardon@google.com> Cc: Yanan Wang <wangyanan55@huawei.com> Cc: Andrew Jones <drjones@redhat.com> Cc: Peter Xu <peterx@redhat.com> Cc: Aaron Lewis <aaronlewis@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> --- tools/testing/selftests/kvm/lib/kvm_util.c | 2 ++ tools/testing/selftests/kvm/lib/perf_test_util.c | 9 +++++++++ 2 files changed, 11 insertions(+)