[PATCH v9 4/5] KVM: selftests: Add selftest for KVM statistics data binary interface

Jing Zhang
2021-06-14T21:23:06Z

Add selftest to check KVM stats descriptors validity.

Reviewed-by: David Matlack <dmatlack@google.com>
Reviewed-by: Ricardo Koller <ricarkol@google.com>
Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Signed-off-by: Jing Zhang <jingzhangos@google.com>
---
tools/testing/selftests/kvm/.gitignore | 1 +
tools/testing/selftests/kvm/Makefile | 3 +
.../testing/selftests/kvm/include/kvm_util.h | 3 +
.../selftests/kvm/kvm_binary_stats_test.c | 225 ++++++++++++++++++
tools/testing/selftests/kvm/lib/kvm_util.c | 12 +
5 files changed, 244 insertions(+)
create mode 100644 tools/testing/selftests/kvm/kvm_binary_stats_test.c

diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
index e0e14150744e..ebe81d67c738 100644
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -46,3 +46,4 @@
/memslot_perf_test
/set_memory_region_test
/steal_time
+/kvm_binary_stats_test
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 61e2accd080d..8e4eaf8cdc06 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -79,6 +79,7 @@ TEST_GEN_PROGS_x86_64 += memslot_modification_stress_test
TEST_GEN_PROGS_x86_64 += memslot_perf_test
TEST_GEN_PROGS_x86_64 += set_memory_region_test
TEST_GEN_PROGS_x86_64 += steal_time
+TEST_GEN_PROGS_x86_64 += kvm_binary_stats_test

TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list
TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list-sve
@@ -90,6 +91,7 @@ TEST_GEN_PROGS_aarch64 += kvm_create_max_vcpus
TEST_GEN_PROGS_aarch64 += kvm_page_table_test
TEST_GEN_PROGS_aarch64 += set_memory_region_test
TEST_GEN_PROGS_aarch64 += steal_time
+TEST_GEN_PROGS_aarch64 += kvm_binary_stats_test

TEST_GEN_PROGS_s390x = s390x/memop
TEST_GEN_PROGS_s390x += s390x/resets
@@ -99,6 +101,7 @@ TEST_GEN_PROGS_s390x += dirty_log_test
TEST_GEN_PROGS_s390x += kvm_create_max_vcpus
TEST_GEN_PROGS_s390x += kvm_page_table_test
TEST_GEN_PROGS_s390x += set_memory_region_test
+TEST_GEN_PROGS_s390x += kvm_binary_stats_test

TEST_GEN_PROGS += $(TEST_GEN_PROGS_$(UNAME_M))
LIBKVM += $(LIBKVM_$(UNAME_M))
diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index 35739567189e..558b450f3d7c 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -391,4 +391,7 @@ uint64_t get_ucall(struct kvm_vm *vm, uint32_t vcpu_id, struct ucall *uc);
#define GUEST_ASSERT_4(_condition, arg1, arg2, arg3, arg4) \
__GUEST_ASSERT((_condition), 4, (arg1), (arg2), (arg3), (arg4))

+int vm_get_stats_fd(struct kvm_vm *vm);
+int vcpu_get_stats_fd(struct kvm_vm *vm, uint32_t vcpuid);
+
#endif /* SELFTEST_KVM_UTIL_H */
diff --git a/tools/testing/selftests/kvm/kvm_binary_stats_test.c b/tools/testing/selftests/kvm/kvm_binary_stats_test.c
new file mode 100644
index 000000000000..f20870ae9296
--- /dev/null
+++ b/tools/testing/selftests/kvm/kvm_binary_stats_test.c
@@ -0,0 +1,225 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * kvm_binary_stats_test
+ *
+ * Copyright (C) 2021, Google LLC.
+ *
+ * Test the fd-based interface for KVM statistics.
+ */
+
+#define _GNU_SOURCE /* for program_invocation_short_name */
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include "test_util.h"
+
+#include "kvm_util.h"
+#include "asm/kvm.h"
+#include "linux/kvm.h"
+
+static void stats_test(int stats_fd)
+{
+ ssize_t ret;
+ int i;
+ size_t size_desc, size_data = 0;
+ struct kvm_stats_header *header;
+ struct kvm_stats_desc *stats_desc, *pdesc;
+ struct kvm_stats_data *stats_data;
+ size_t size_header = sizeof(*header) + KVM_STATS_ID_MAXLEN;
+
+ /* Read kvm stats header */
+ header = malloc(size_header);
+ TEST_ASSERT(header, "Allocate memory for stats header");
+
+ ret = read(stats_fd, header, size_header);
+ TEST_ASSERT(ret == size_header, "Read stats header");
+ size_desc = sizeof(*stats_desc) + header->name_size;
+
+ /* Check id string in header, that should start with "kvm" */
+ TEST_ASSERT(!strncmp(header->id, "kvm", 3) &&
+ strlen(header->id) < KVM_STATS_ID_MAXLEN,
+ "Invalid KVM stats type, id: %s", header->id);
+
+ /* Sanity check for other fields in header */
+ if (header->count == 0) {
+ printf("No KVM stats defined!");
+ return;
+ }
+ /* Check overlap */
+ TEST_ASSERT(header->desc_offset > 0 && header->data_offset > 0
+ && header->desc_offset >= size_header
+ && header->data_offset >= size_header,
+ "Invalid offset fields in header");
+ TEST_ASSERT(header->desc_offset > header->data_offset
+ || (header->desc_offset + size_desc * header->count <=
+ header->data_offset),
+ "Descriptor block is overlapped with data block");
+
+ /* Allocate memory for stats descriptors */
+ stats_desc = calloc(header->count, size_desc);
+ TEST_ASSERT(stats_desc, "Allocate memory for stats descriptors");
+ /* Read kvm stats descriptors */
+ ret = pread(stats_fd, stats_desc,
+ size_desc * header->count, header->desc_offset);
+ TEST_ASSERT(ret == size_desc * header->count,
+ "Read KVM stats descriptors");
+
+ /* Sanity check for fields in descriptors */
+ for (i = 0; i < header->count; ++i) {
+ pdesc = (void *)stats_desc + i * size_desc;
+ /* Check type,unit,base boundaries */
+ TEST_ASSERT((pdesc->flags & KVM_STATS_TYPE_MASK)
+ <= KVM_STATS_TYPE_MAX, "Unknown KVM stats type");
+ TEST_ASSERT((pdesc->flags & KVM_STATS_UNIT_MASK)
+ <= KVM_STATS_UNIT_MAX, "Unknown KVM stats unit");
+ TEST_ASSERT((pdesc->flags & KVM_STATS_BASE_MASK)
+ <= KVM_STATS_BASE_MAX, "Unknown KVM stats base");
+ /* Check exponent for stats unit
+ * Exponent for counter should be greater than or equal to 0
+ * Exponent for unit bytes should be greater than or equal to 0
+ * Exponent for unit seconds should be less than or equal to 0
+ * Exponent for unit clock cycles should be greater than or
+ * equal to 0
+ */
+ switch (pdesc->flags & KVM_STATS_UNIT_MASK) {
+ case KVM_STATS_UNIT_NONE:
+ case KVM_STATS_UNIT_BYTES:
+ case KVM_STATS_UNIT_CYCLES:
+ TEST_ASSERT(pdesc->exponent >= 0,
+ "Unsupported KVM stats unit");
+ break;
+ case KVM_STATS_UNIT_SECONDS:
+ TEST_ASSERT(pdesc->exponent <= 0,
+ "Unsupported KVM stats unit");
+ break;
+ }
+ /* Check name string */
+ TEST_ASSERT(strlen(pdesc->name) < header->name_size,
+ "KVM stats name(%s) too long", pdesc->name);
+ /* Check size field, which should not be zero */
+ TEST_ASSERT(pdesc->size, "KVM descriptor(%s) with size of 0",
+ pdesc->name);
+ size_data += pdesc->size * sizeof(stats_data->value[0]);
+ }
+ /* Check overlap */
+ TEST_ASSERT(header->data_offset >= header->desc_offset
+ || header->data_offset + size_data <= header->desc_offset,
+ "Data block is overlapped with Descriptor block");
+ /* Check validity of all stats data size */
+ TEST_ASSERT(size_data >= header->count * sizeof(stats_data->value[0]),
+ "Data size is not correct");
+ /* Check stats offset */
+ for (i = 0; i < header->count; ++i) {
+ pdesc = (void *)stats_desc + i * size_desc;
+ TEST_ASSERT(pdesc->offset < size_data,
+ "Invalid offset (%u) for stats: %s",
+ pdesc->offset, pdesc->name);
+ }
+
+ /* Allocate memory for stats data */
+ stats_data = malloc(size_data);
+ TEST_ASSERT(stats_data, "Allocate memory for stats data");
+ /* Read kvm stats data as a bulk */
+ ret = pread(stats_fd, stats_data, size_data, header->data_offset);
+ TEST_ASSERT(ret == size_data, "Read KVM stats data");
+ /* Read kvm stats data one by one */
+ size_data = 0;
+ for (i = 0; i < header->count; ++i) {
+ pdesc = (void *)stats_desc + i * size_desc;
+ ret = pread(stats_fd, stats_data,
+ pdesc->size * sizeof(stats_data->value[0]),
+ header->data_offset + size_data);
+ TEST_ASSERT(ret == pdesc->size * sizeof(stats_data->value[0]),
+ "Read data of KVM stats: %s", pdesc->name);
+ size_data += pdesc->size * sizeof(stats_data->value[0]);
+ }
+
+ free(stats_data);
+ free(stats_desc);
+}
+
+
+static void vm_stats_test(struct kvm_vm *vm)
+{
+ int stats_fd;
+
+ /* Get fd for VM stats */
+ stats_fd = vm_get_stats_fd(vm);
+ TEST_ASSERT(stats_fd >= 0, "Get VM stats fd");
+
+ stats_test(stats_fd);
+ close(stats_fd);
+ TEST_ASSERT(fcntl(stats_fd, F_GETFD) == -1, "Stats fd not freed");
+}
+
+static void vcpu_stats_test(struct kvm_vm *vm, int vcpu_id)
+{
+ int stats_fd;
+
+ /* Get fd for VCPU stats */
+ stats_fd = vcpu_get_stats_fd(vm, vcpu_id);
+ TEST_ASSERT(stats_fd >= 0, "Get VCPU stats fd");
+
+ stats_test(stats_fd);
+ close(stats_fd);
+ TEST_ASSERT(fcntl(stats_fd, F_GETFD) == -1, "Stats fd not freed");
+}
+
+#define DEFAULT_NUM_VM 4
+#define DEFAULT_NUM_VCPU 4
+
+/*
+ * Usage: kvm_bin_form_stats [#vm] [#vcpu]
+ * The first parameter #vm set the number of VMs being created.
+ * The second parameter #vcpu set the number of VCPUs being created.
+ * By default, DEFAULT_NUM_VM VM and DEFAULT_NUM_VCPU VCPU for the VM would be
+ * created for testing.
+ */
+
+int main(int argc, char *argv[])
+{
+ int max_vm = DEFAULT_NUM_VM, max_vcpu = DEFAULT_NUM_VCPU, ret, i, j;
+ struct kvm_vm **vms;
+
+ /* Get the number of VMs and VCPUs that would be created for testing. */
+ if (argc > 1) {
+ max_vm = strtol(argv[1], NULL, 0);
+ if (max_vm <= 0)
+ max_vm = DEFAULT_NUM_VM;
+ }
+ if (argc > 2) {
+ max_vcpu = strtol(argv[2], NULL, 0);
+ if (max_vcpu <= 0)
+ max_vcpu = DEFAULT_NUM_VCPU;
+ }
+
+ /* Check the extension for binary stats */
+ ret = kvm_check_cap(KVM_CAP_BINARY_STATS_FD);
+ TEST_ASSERT(ret >= 0,
+ "Binary form statistics interface is not supported");
+
+ /* Create VMs and VCPUs */
+ vms = malloc(sizeof(vms[0]) * max_vm);
+ TEST_ASSERT(vms, "Allocate memory for storing VM pointers");
+ for (i = 0; i < max_vm; ++i) {
+ vms[i] = vm_create(VM_MODE_DEFAULT,
+ DEFAULT_GUEST_PHY_PAGES, O_RDWR);
+ for (j = 0; j < max_vcpu; ++j)
+ vm_vcpu_add(vms[i], j);
+ }
+
+ /* Check stats read for every VM and VCPU */
+ for (i = 0; i < max_vm; ++i) {
+ vm_stats_test(vms[i]);
+ for (j = 0; j < max_vcpu; ++j)
+ vcpu_stats_test(vms[i], j);
+ }
+
+ for (i = 0; i < max_vm; ++i)
+ kvm_vm_free(vms[i]);
+ free(vms);
+ return 0;
+}
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 5c70596dd1b9..83c02cb0ae1e 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -2286,3 +2286,15 @@ unsigned int vm_calc_num_guest_pages(enum vm_guest_mode mode, size_t size)
n = DIV_ROUND_UP(size, vm_guest_mode_params[mode].page_size);
return vm_adjust_num_guest_pages(mode, n);
}
+
+int vm_get_stats_fd(struct kvm_vm *vm)
+{
+ return ioctl(vm->fd, KVM_GET_STATS_FD, NULL);
+}
+
+int vcpu_get_stats_fd(struct kvm_vm *vm, uint32_t vcpuid)
+{
+ struct vcpu *vcpu = vcpu_find(vm, vcpuid);
+
+ return ioctl(vcpu->fd, KVM_GET_STATS_FD, NULL);
+}
--
2.32.0.272.g935e593368-goog