diff mbox series

[RFC,v2,2/7] KVM: selftests: Use flag CLOCK_MONOTONIC_RAW for timing

Message ID 20210225055940.18748-3-wangyanan55@huawei.com (mailing list archive)
State New, archived
Headers show
Series Some improvement and a new test for kvm page table | expand

Commit Message

Yanan Wang Feb. 25, 2021, 5:59 a.m. UTC
In addition to function of CLOCK_MONOTONIC, flag CLOCK_MONOTONIC_RAW can
also shield possiable impact of NTP, which can provide more robustness.

Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
---
 tools/testing/selftests/kvm/demand_paging_test.c  |  8 ++++----
 tools/testing/selftests/kvm/dirty_log_perf_test.c | 14 +++++++-------
 tools/testing/selftests/kvm/lib/test_util.c       |  2 +-
 tools/testing/selftests/kvm/steal_time.c          |  4 ++--
 4 files changed, 14 insertions(+), 14 deletions(-)

Comments

Andrew Jones Feb. 25, 2021, 6:54 p.m. UTC | #1
On Thu, Feb 25, 2021 at 01:59:35PM +0800, Yanan Wang wrote:
> In addition to function of CLOCK_MONOTONIC, flag CLOCK_MONOTONIC_RAW can
> also shield possiable impact of NTP, which can provide more robustness.

IIRC, this should include

Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>

> 
> Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
> ---
>  tools/testing/selftests/kvm/demand_paging_test.c  |  8 ++++----
>  tools/testing/selftests/kvm/dirty_log_perf_test.c | 14 +++++++-------
>  tools/testing/selftests/kvm/lib/test_util.c       |  2 +-
>  tools/testing/selftests/kvm/steal_time.c          |  4 ++--
>  4 files changed, 14 insertions(+), 14 deletions(-)
> 
> diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
> index 5f7a229c3af1..efbf0c1e9130 100644
> --- a/tools/testing/selftests/kvm/demand_paging_test.c
> +++ b/tools/testing/selftests/kvm/demand_paging_test.c
> @@ -53,7 +53,7 @@ static void *vcpu_worker(void *data)
>  	vcpu_args_set(vm, vcpu_id, 1, vcpu_id);
>  	run = vcpu_state(vm, vcpu_id);
>  
> -	clock_gettime(CLOCK_MONOTONIC, &start);
> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>  
>  	/* Let the guest access its memory */
>  	ret = _vcpu_run(vm, vcpu_id);
> @@ -86,7 +86,7 @@ static int handle_uffd_page_request(int uffd, uint64_t addr)
>  	copy.len = perf_test_args.host_page_size;
>  	copy.mode = 0;
>  
> -	clock_gettime(CLOCK_MONOTONIC, &start);
> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>  
>  	r = ioctl(uffd, UFFDIO_COPY, &copy);
>  	if (r == -1) {
> @@ -123,7 +123,7 @@ static void *uffd_handler_thread_fn(void *arg)
>  	struct timespec start;
>  	struct timespec ts_diff;
>  
> -	clock_gettime(CLOCK_MONOTONIC, &start);
> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>  	while (!quit_uffd_thread) {
>  		struct uffd_msg msg;
>  		struct pollfd pollfd[2];
> @@ -336,7 +336,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>  
>  	pr_info("Finished creating vCPUs and starting uffd threads\n");
>  
> -	clock_gettime(CLOCK_MONOTONIC, &start);
> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>  
>  	for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) {
>  		pthread_create(&vcpu_threads[vcpu_id], NULL, vcpu_worker,
> diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c
> index 04a2641261be..6cff4ccf9525 100644
> --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c
> +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c
> @@ -50,7 +50,7 @@ static void *vcpu_worker(void *data)
>  	while (!READ_ONCE(host_quit)) {
>  		int current_iteration = READ_ONCE(iteration);
>  
> -		clock_gettime(CLOCK_MONOTONIC, &start);
> +		clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>  		ret = _vcpu_run(vm, vcpu_id);
>  		ts_diff = timespec_elapsed(start);
>  
> @@ -141,7 +141,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>  	iteration = 0;
>  	host_quit = false;
>  
> -	clock_gettime(CLOCK_MONOTONIC, &start);
> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>  	for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) {
>  		vcpu_last_completed_iteration[vcpu_id] = -1;
>  
> @@ -162,7 +162,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>  		ts_diff.tv_sec, ts_diff.tv_nsec);
>  
>  	/* Enable dirty logging */
> -	clock_gettime(CLOCK_MONOTONIC, &start);
> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>  	vm_mem_region_set_flags(vm, PERF_TEST_MEM_SLOT_INDEX,
>  				KVM_MEM_LOG_DIRTY_PAGES);
>  	ts_diff = timespec_elapsed(start);
> @@ -174,7 +174,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>  		 * Incrementing the iteration number will start the vCPUs
>  		 * dirtying memory again.
>  		 */
> -		clock_gettime(CLOCK_MONOTONIC, &start);
> +		clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>  		iteration++;
>  
>  		pr_debug("Starting iteration %d\n", iteration);
> @@ -189,7 +189,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>  		pr_info("Iteration %d dirty memory time: %ld.%.9lds\n",
>  			iteration, ts_diff.tv_sec, ts_diff.tv_nsec);
>  
> -		clock_gettime(CLOCK_MONOTONIC, &start);
> +		clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>  		kvm_vm_get_dirty_log(vm, PERF_TEST_MEM_SLOT_INDEX, bmap);
>  
>  		ts_diff = timespec_elapsed(start);
> @@ -199,7 +199,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>  			iteration, ts_diff.tv_sec, ts_diff.tv_nsec);
>  
>  		if (dirty_log_manual_caps) {
> -			clock_gettime(CLOCK_MONOTONIC, &start);
> +			clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>  			kvm_vm_clear_dirty_log(vm, PERF_TEST_MEM_SLOT_INDEX, bmap, 0,
>  					       host_num_pages);
>  
> @@ -212,7 +212,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>  	}
>  
>  	/* Disable dirty logging */
> -	clock_gettime(CLOCK_MONOTONIC, &start);
> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>  	vm_mem_region_set_flags(vm, PERF_TEST_MEM_SLOT_INDEX, 0);
>  	ts_diff = timespec_elapsed(start);
>  	pr_info("Disabling dirty logging time: %ld.%.9lds\n",
> diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c
> index 906c955384e2..c7c0627c6842 100644
> --- a/tools/testing/selftests/kvm/lib/test_util.c
> +++ b/tools/testing/selftests/kvm/lib/test_util.c
> @@ -89,7 +89,7 @@ struct timespec timespec_elapsed(struct timespec start)
>  {
>  	struct timespec end;
>  
> -	clock_gettime(CLOCK_MONOTONIC, &end);
> +	clock_gettime(CLOCK_MONOTONIC_RAW, &end);
>  	return timespec_sub(end, start);
>  }
>  
> diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c
> index fcc840088c91..5bc582d3f2a2 100644
> --- a/tools/testing/selftests/kvm/steal_time.c
> +++ b/tools/testing/selftests/kvm/steal_time.c
> @@ -237,11 +237,11 @@ static void *do_steal_time(void *arg)
>  {
>  	struct timespec ts, stop;
>  
> -	clock_gettime(CLOCK_MONOTONIC, &ts);
> +	clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
>  	stop = timespec_add_ns(ts, MIN_RUN_DELAY_NS);
>  
>  	while (1) {
> -		clock_gettime(CLOCK_MONOTONIC, &ts);
> +		clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
>  		if (timespec_to_ns(timespec_sub(ts, stop)) >= 0)
>  			break;
>  	}
> -- 
> 2.19.1
>
Yanan Wang Feb. 26, 2021, 2:49 a.m. UTC | #2
On 2021/2/26 2:54, Andrew Jones wrote:
> On Thu, Feb 25, 2021 at 01:59:35PM +0800, Yanan Wang wrote:
>> In addition to function of CLOCK_MONOTONIC, flag CLOCK_MONOTONIC_RAW can
>> also shield possiable impact of NTP, which can provide more robustness.
> IIRC, this should include
>
> Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>

Oh, sorry for my rashness. I will include it in v3.

Thanks,

Yanan

>> Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
>> ---
>>   tools/testing/selftests/kvm/demand_paging_test.c  |  8 ++++----
>>   tools/testing/selftests/kvm/dirty_log_perf_test.c | 14 +++++++-------
>>   tools/testing/selftests/kvm/lib/test_util.c       |  2 +-
>>   tools/testing/selftests/kvm/steal_time.c          |  4 ++--
>>   4 files changed, 14 insertions(+), 14 deletions(-)
>>
>> diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
>> index 5f7a229c3af1..efbf0c1e9130 100644
>> --- a/tools/testing/selftests/kvm/demand_paging_test.c
>> +++ b/tools/testing/selftests/kvm/demand_paging_test.c
>> @@ -53,7 +53,7 @@ static void *vcpu_worker(void *data)
>>   	vcpu_args_set(vm, vcpu_id, 1, vcpu_id);
>>   	run = vcpu_state(vm, vcpu_id);
>>   
>> -	clock_gettime(CLOCK_MONOTONIC, &start);
>> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>>   
>>   	/* Let the guest access its memory */
>>   	ret = _vcpu_run(vm, vcpu_id);
>> @@ -86,7 +86,7 @@ static int handle_uffd_page_request(int uffd, uint64_t addr)
>>   	copy.len = perf_test_args.host_page_size;
>>   	copy.mode = 0;
>>   
>> -	clock_gettime(CLOCK_MONOTONIC, &start);
>> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>>   
>>   	r = ioctl(uffd, UFFDIO_COPY, &copy);
>>   	if (r == -1) {
>> @@ -123,7 +123,7 @@ static void *uffd_handler_thread_fn(void *arg)
>>   	struct timespec start;
>>   	struct timespec ts_diff;
>>   
>> -	clock_gettime(CLOCK_MONOTONIC, &start);
>> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>>   	while (!quit_uffd_thread) {
>>   		struct uffd_msg msg;
>>   		struct pollfd pollfd[2];
>> @@ -336,7 +336,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>>   
>>   	pr_info("Finished creating vCPUs and starting uffd threads\n");
>>   
>> -	clock_gettime(CLOCK_MONOTONIC, &start);
>> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>>   
>>   	for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) {
>>   		pthread_create(&vcpu_threads[vcpu_id], NULL, vcpu_worker,
>> diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c
>> index 04a2641261be..6cff4ccf9525 100644
>> --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c
>> +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c
>> @@ -50,7 +50,7 @@ static void *vcpu_worker(void *data)
>>   	while (!READ_ONCE(host_quit)) {
>>   		int current_iteration = READ_ONCE(iteration);
>>   
>> -		clock_gettime(CLOCK_MONOTONIC, &start);
>> +		clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>>   		ret = _vcpu_run(vm, vcpu_id);
>>   		ts_diff = timespec_elapsed(start);
>>   
>> @@ -141,7 +141,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>>   	iteration = 0;
>>   	host_quit = false;
>>   
>> -	clock_gettime(CLOCK_MONOTONIC, &start);
>> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>>   	for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) {
>>   		vcpu_last_completed_iteration[vcpu_id] = -1;
>>   
>> @@ -162,7 +162,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>>   		ts_diff.tv_sec, ts_diff.tv_nsec);
>>   
>>   	/* Enable dirty logging */
>> -	clock_gettime(CLOCK_MONOTONIC, &start);
>> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>>   	vm_mem_region_set_flags(vm, PERF_TEST_MEM_SLOT_INDEX,
>>   				KVM_MEM_LOG_DIRTY_PAGES);
>>   	ts_diff = timespec_elapsed(start);
>> @@ -174,7 +174,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>>   		 * Incrementing the iteration number will start the vCPUs
>>   		 * dirtying memory again.
>>   		 */
>> -		clock_gettime(CLOCK_MONOTONIC, &start);
>> +		clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>>   		iteration++;
>>   
>>   		pr_debug("Starting iteration %d\n", iteration);
>> @@ -189,7 +189,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>>   		pr_info("Iteration %d dirty memory time: %ld.%.9lds\n",
>>   			iteration, ts_diff.tv_sec, ts_diff.tv_nsec);
>>   
>> -		clock_gettime(CLOCK_MONOTONIC, &start);
>> +		clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>>   		kvm_vm_get_dirty_log(vm, PERF_TEST_MEM_SLOT_INDEX, bmap);
>>   
>>   		ts_diff = timespec_elapsed(start);
>> @@ -199,7 +199,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>>   			iteration, ts_diff.tv_sec, ts_diff.tv_nsec);
>>   
>>   		if (dirty_log_manual_caps) {
>> -			clock_gettime(CLOCK_MONOTONIC, &start);
>> +			clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>>   			kvm_vm_clear_dirty_log(vm, PERF_TEST_MEM_SLOT_INDEX, bmap, 0,
>>   					       host_num_pages);
>>   
>> @@ -212,7 +212,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>>   	}
>>   
>>   	/* Disable dirty logging */
>> -	clock_gettime(CLOCK_MONOTONIC, &start);
>> +	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
>>   	vm_mem_region_set_flags(vm, PERF_TEST_MEM_SLOT_INDEX, 0);
>>   	ts_diff = timespec_elapsed(start);
>>   	pr_info("Disabling dirty logging time: %ld.%.9lds\n",
>> diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c
>> index 906c955384e2..c7c0627c6842 100644
>> --- a/tools/testing/selftests/kvm/lib/test_util.c
>> +++ b/tools/testing/selftests/kvm/lib/test_util.c
>> @@ -89,7 +89,7 @@ struct timespec timespec_elapsed(struct timespec start)
>>   {
>>   	struct timespec end;
>>   
>> -	clock_gettime(CLOCK_MONOTONIC, &end);
>> +	clock_gettime(CLOCK_MONOTONIC_RAW, &end);
>>   	return timespec_sub(end, start);
>>   }
>>   
>> diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c
>> index fcc840088c91..5bc582d3f2a2 100644
>> --- a/tools/testing/selftests/kvm/steal_time.c
>> +++ b/tools/testing/selftests/kvm/steal_time.c
>> @@ -237,11 +237,11 @@ static void *do_steal_time(void *arg)
>>   {
>>   	struct timespec ts, stop;
>>   
>> -	clock_gettime(CLOCK_MONOTONIC, &ts);
>> +	clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
>>   	stop = timespec_add_ns(ts, MIN_RUN_DELAY_NS);
>>   
>>   	while (1) {
>> -		clock_gettime(CLOCK_MONOTONIC, &ts);
>> +		clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
>>   		if (timespec_to_ns(timespec_sub(ts, stop)) >= 0)
>>   			break;
>>   	}
>> -- 
>> 2.19.1
>>
> .
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 5f7a229c3af1..efbf0c1e9130 100644
--- a/tools/testing/selftests/kvm/demand_paging_test.c
+++ b/tools/testing/selftests/kvm/demand_paging_test.c
@@ -53,7 +53,7 @@  static void *vcpu_worker(void *data)
 	vcpu_args_set(vm, vcpu_id, 1, vcpu_id);
 	run = vcpu_state(vm, vcpu_id);
 
-	clock_gettime(CLOCK_MONOTONIC, &start);
+	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
 
 	/* Let the guest access its memory */
 	ret = _vcpu_run(vm, vcpu_id);
@@ -86,7 +86,7 @@  static int handle_uffd_page_request(int uffd, uint64_t addr)
 	copy.len = perf_test_args.host_page_size;
 	copy.mode = 0;
 
-	clock_gettime(CLOCK_MONOTONIC, &start);
+	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
 
 	r = ioctl(uffd, UFFDIO_COPY, &copy);
 	if (r == -1) {
@@ -123,7 +123,7 @@  static void *uffd_handler_thread_fn(void *arg)
 	struct timespec start;
 	struct timespec ts_diff;
 
-	clock_gettime(CLOCK_MONOTONIC, &start);
+	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
 	while (!quit_uffd_thread) {
 		struct uffd_msg msg;
 		struct pollfd pollfd[2];
@@ -336,7 +336,7 @@  static void run_test(enum vm_guest_mode mode, void *arg)
 
 	pr_info("Finished creating vCPUs and starting uffd threads\n");
 
-	clock_gettime(CLOCK_MONOTONIC, &start);
+	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
 
 	for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) {
 		pthread_create(&vcpu_threads[vcpu_id], NULL, vcpu_worker,
diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c
index 04a2641261be..6cff4ccf9525 100644
--- a/tools/testing/selftests/kvm/dirty_log_perf_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c
@@ -50,7 +50,7 @@  static void *vcpu_worker(void *data)
 	while (!READ_ONCE(host_quit)) {
 		int current_iteration = READ_ONCE(iteration);
 
-		clock_gettime(CLOCK_MONOTONIC, &start);
+		clock_gettime(CLOCK_MONOTONIC_RAW, &start);
 		ret = _vcpu_run(vm, vcpu_id);
 		ts_diff = timespec_elapsed(start);
 
@@ -141,7 +141,7 @@  static void run_test(enum vm_guest_mode mode, void *arg)
 	iteration = 0;
 	host_quit = false;
 
-	clock_gettime(CLOCK_MONOTONIC, &start);
+	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
 	for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) {
 		vcpu_last_completed_iteration[vcpu_id] = -1;
 
@@ -162,7 +162,7 @@  static void run_test(enum vm_guest_mode mode, void *arg)
 		ts_diff.tv_sec, ts_diff.tv_nsec);
 
 	/* Enable dirty logging */
-	clock_gettime(CLOCK_MONOTONIC, &start);
+	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
 	vm_mem_region_set_flags(vm, PERF_TEST_MEM_SLOT_INDEX,
 				KVM_MEM_LOG_DIRTY_PAGES);
 	ts_diff = timespec_elapsed(start);
@@ -174,7 +174,7 @@  static void run_test(enum vm_guest_mode mode, void *arg)
 		 * Incrementing the iteration number will start the vCPUs
 		 * dirtying memory again.
 		 */
-		clock_gettime(CLOCK_MONOTONIC, &start);
+		clock_gettime(CLOCK_MONOTONIC_RAW, &start);
 		iteration++;
 
 		pr_debug("Starting iteration %d\n", iteration);
@@ -189,7 +189,7 @@  static void run_test(enum vm_guest_mode mode, void *arg)
 		pr_info("Iteration %d dirty memory time: %ld.%.9lds\n",
 			iteration, ts_diff.tv_sec, ts_diff.tv_nsec);
 
-		clock_gettime(CLOCK_MONOTONIC, &start);
+		clock_gettime(CLOCK_MONOTONIC_RAW, &start);
 		kvm_vm_get_dirty_log(vm, PERF_TEST_MEM_SLOT_INDEX, bmap);
 
 		ts_diff = timespec_elapsed(start);
@@ -199,7 +199,7 @@  static void run_test(enum vm_guest_mode mode, void *arg)
 			iteration, ts_diff.tv_sec, ts_diff.tv_nsec);
 
 		if (dirty_log_manual_caps) {
-			clock_gettime(CLOCK_MONOTONIC, &start);
+			clock_gettime(CLOCK_MONOTONIC_RAW, &start);
 			kvm_vm_clear_dirty_log(vm, PERF_TEST_MEM_SLOT_INDEX, bmap, 0,
 					       host_num_pages);
 
@@ -212,7 +212,7 @@  static void run_test(enum vm_guest_mode mode, void *arg)
 	}
 
 	/* Disable dirty logging */
-	clock_gettime(CLOCK_MONOTONIC, &start);
+	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
 	vm_mem_region_set_flags(vm, PERF_TEST_MEM_SLOT_INDEX, 0);
 	ts_diff = timespec_elapsed(start);
 	pr_info("Disabling dirty logging time: %ld.%.9lds\n",
diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c
index 906c955384e2..c7c0627c6842 100644
--- a/tools/testing/selftests/kvm/lib/test_util.c
+++ b/tools/testing/selftests/kvm/lib/test_util.c
@@ -89,7 +89,7 @@  struct timespec timespec_elapsed(struct timespec start)
 {
 	struct timespec end;
 
-	clock_gettime(CLOCK_MONOTONIC, &end);
+	clock_gettime(CLOCK_MONOTONIC_RAW, &end);
 	return timespec_sub(end, start);
 }
 
diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c
index fcc840088c91..5bc582d3f2a2 100644
--- a/tools/testing/selftests/kvm/steal_time.c
+++ b/tools/testing/selftests/kvm/steal_time.c
@@ -237,11 +237,11 @@  static void *do_steal_time(void *arg)
 {
 	struct timespec ts, stop;
 
-	clock_gettime(CLOCK_MONOTONIC, &ts);
+	clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
 	stop = timespec_add_ns(ts, MIN_RUN_DELAY_NS);
 
 	while (1) {
-		clock_gettime(CLOCK_MONOTONIC, &ts);
+		clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
 		if (timespec_to_ns(timespec_sub(ts, stop)) >= 0)
 			break;
 	}