Wrfract will be used by the dirty logging perf test introduced later in this series to dirty memory sparsely. Signed-off-by: Ben Gardon <bgardon@xxxxxxxxxx> --- tools/testing/selftests/kvm/demand_paging_test.c | 2 ++ tools/testing/selftests/kvm/include/perf_test_util.h | 1 + tools/testing/selftests/kvm/lib/perf_test_util.c | 5 ++++- 3 files changed, 7 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c index 63ea7c06e1141..72b8890c0dc3b 100644 --- a/tools/testing/selftests/kvm/demand_paging_test.c +++ b/tools/testing/selftests/kvm/demand_paging_test.c @@ -264,6 +264,8 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd, int vcpu_id; int r; + perf_test_args.wr_fract = 1; + vm = create_vm(mode, vcpus, vcpu_memory_bytes); guest_data_prototype = malloc(perf_test_args.host_page_size); diff --git a/tools/testing/selftests/kvm/include/perf_test_util.h b/tools/testing/selftests/kvm/include/perf_test_util.h index 4d52b9ee13c42..645b942ae0229 100644 --- a/tools/testing/selftests/kvm/include/perf_test_util.h +++ b/tools/testing/selftests/kvm/include/perf_test_util.h @@ -36,6 +36,7 @@ struct perf_test_args { struct kvm_vm *vm; uint64_t host_page_size; uint64_t guest_page_size; + int wr_fract; struct vcpu_args vcpu_args[MAX_VCPUS]; }; diff --git a/tools/testing/selftests/kvm/lib/perf_test_util.c b/tools/testing/selftests/kvm/lib/perf_test_util.c index fa7efbac9ef8a..1abb6b1321c3c 100644 --- a/tools/testing/selftests/kvm/lib/perf_test_util.c +++ b/tools/testing/selftests/kvm/lib/perf_test_util.c @@ -44,7 +44,10 @@ void guest_code(uint32_t vcpu_id) for (i = 0; i < pages; i++) { uint64_t addr = gva + (i * perf_test_args.guest_page_size); - *(uint64_t *)addr = 0x0123456789ABCDEF; + if (i % perf_test_args.wr_fract == 0) + *(uint64_t *)addr = 0x0123456789ABCDEF; + else + READ_ONCE(*(uint64_t *)addr); } GUEST_SYNC(1); -- 2.29.1.341.ge80a0c044ae-goog