diff mbox series

[4/5] KVM: selftests: Add wrfract to common guest code

Message ID 20201027233733.1484855-5-bgardon@google.com
State Accepted
Commit 92ab4b9a22cfea9b0d353e86024208040c10e807
Headers show
Series Add a dirty logging performance test | expand

Commit Message

Ben Gardon Oct. 27, 2020, 11:37 p.m. UTC
Wrfract will be used by the dirty logging perf test introduced later in
this series to dirty memory sparsely.

This series was tested by running the following invocations on an Intel
Skylake machine:
dirty_log_perf_test -b 20m -i 100 -v 64
dirty_log_perf_test -b 20g -i 5 -v 4
dirty_log_perf_test -b 4g -i 5 -v 32
demand_paging_test -b 20m -v 64
demand_paging_test -b 20g -v 4
demand_paging_test -b 4g -v 32
All behaved as expected.

Signed-off-by: Ben Gardon <bgardon@google.com>
---
 tools/testing/selftests/kvm/demand_paging_test.c     | 2 ++
 tools/testing/selftests/kvm/include/perf_test_util.h | 6 +++++-
 2 files changed, 7 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
index 7de6feb000760..47defc65aedac 100644
--- a/tools/testing/selftests/kvm/demand_paging_test.c
+++ b/tools/testing/selftests/kvm/demand_paging_test.c
@@ -266,6 +266,8 @@  static void run_test(enum vm_guest_mode mode, bool use_uffd,
 
 	vm = create_vm(mode, vcpus, vcpu_memory_bytes);
 
+	perf_test_args.wr_fract = 1;
+
 	guest_data_prototype = malloc(perf_test_args.host_page_size);
 	TEST_ASSERT(guest_data_prototype,
 		    "Failed to allocate buffer for guest data pattern");
diff --git a/tools/testing/selftests/kvm/include/perf_test_util.h b/tools/testing/selftests/kvm/include/perf_test_util.h
index 838f946700f0c..1716300469c04 100644
--- a/tools/testing/selftests/kvm/include/perf_test_util.h
+++ b/tools/testing/selftests/kvm/include/perf_test_util.h
@@ -46,6 +46,7 @@  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];
 };
@@ -72,7 +73,10 @@  static 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);