On 16/03/20 18:37, Andrew Jones wrote:
> The steal_time test's timespec stop condition was wrong and should have
> used the timespec functions instead to avoid being wrong, but
> timespec_diff had a strange interface. Rework all the timespec API and
> its use.
>
> Signed-off-by: Andrew Jones <drjones@xxxxxxxxxx>
Queued this one, I have already pushed the test to kvm/next so the
"fixup!" commit cannot be squashed. But I don't really mind the code as
it looks in kvm/next.
Paolo
> ---
> .../selftests/kvm/demand_paging_test.c | 37 ++++++++-----------
> .../testing/selftests/kvm/include/test_util.h | 3 +-
> tools/testing/selftests/kvm/lib/test_util.c | 37 ++++++++-----------
> tools/testing/selftests/kvm/steal_time.c | 2 +-
> 4 files changed, 35 insertions(+), 44 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
> index d82f7bc060c3..360cd3ea4cd6 100644
> --- a/tools/testing/selftests/kvm/demand_paging_test.c
> +++ b/tools/testing/selftests/kvm/demand_paging_test.c
> @@ -117,8 +117,7 @@ static void *vcpu_worker(void *data)
> struct kvm_vm *vm = args->vm;
> int vcpu_id = args->vcpu_id;
> struct kvm_run *run;
> - struct timespec start;
> - struct timespec end;
> + struct timespec start, end, ts_diff;
>
> vcpu_args_set(vm, vcpu_id, 1, vcpu_id);
> run = vcpu_state(vm, vcpu_id);
> @@ -135,9 +134,9 @@ static void *vcpu_worker(void *data)
> }
>
> clock_gettime(CLOCK_MONOTONIC, &end);
> - PER_VCPU_DEBUG("vCPU %d execution time: %lld.%.9lds\n", vcpu_id,
> - (long long)(timespec_diff(start, end).tv_sec),
> - timespec_diff(start, end).tv_nsec);
> + ts_diff = timespec_sub(end, start);
> + PER_VCPU_DEBUG("vCPU %d execution time: %ld.%.9lds\n", vcpu_id,
> + ts_diff.tv_sec, ts_diff.tv_nsec);
>
> return NULL;
> }
> @@ -201,8 +200,8 @@ static int handle_uffd_page_request(int uffd, uint64_t addr)
>
> clock_gettime(CLOCK_MONOTONIC, &end);
>
> - PER_PAGE_DEBUG("UFFDIO_COPY %d \t%lld ns\n", tid,
> - (long long)timespec_to_ns(timespec_diff(start, end)));
> + PER_PAGE_DEBUG("UFFDIO_COPY %d \t%ld ns\n", tid,
> + timespec_to_ns(timespec_sub(end, start)));
> PER_PAGE_DEBUG("Paged in %ld bytes at 0x%lx from thread %d\n",
> host_page_size, addr, tid);
>
> @@ -224,8 +223,7 @@ static void *uffd_handler_thread_fn(void *arg)
> int pipefd = uffd_args->pipefd;
> useconds_t delay = uffd_args->delay;
> int64_t pages = 0;
> - struct timespec start;
> - struct timespec end;
> + struct timespec start, end, ts_diff;
>
> clock_gettime(CLOCK_MONOTONIC, &start);
> while (!quit_uffd_thread) {
> @@ -295,11 +293,10 @@ static void *uffd_handler_thread_fn(void *arg)
> }
>
> clock_gettime(CLOCK_MONOTONIC, &end);
> - PER_VCPU_DEBUG("userfaulted %ld pages over %lld.%.9lds. (%f/sec)\n",
> - pages, (long long)(timespec_diff(start, end).tv_sec),
> - timespec_diff(start, end).tv_nsec, pages /
> - ((double)timespec_diff(start, end).tv_sec +
> - (double)timespec_diff(start, end).tv_nsec / 100000000.0));
> + ts_diff = timespec_sub(end, start);
> + PER_VCPU_DEBUG("userfaulted %ld pages over %ld.%.9lds. (%f/sec)\n",
> + pages, ts_diff.tv_sec, ts_diff.tv_nsec,
> + pages / ((double)ts_diff.tv_sec + (double)ts_diff.tv_nsec / 100000000.0));
>
> return NULL;
> }
> @@ -360,13 +357,12 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd,
> pthread_t *vcpu_threads;
> pthread_t *uffd_handler_threads = NULL;
> struct uffd_handler_args *uffd_args = NULL;
> + struct timespec start, end, ts_diff;
> int *pipefds = NULL;
> struct kvm_vm *vm;
> uint64_t guest_num_pages;
> int vcpu_id;
> int r;
> - struct timespec start;
> - struct timespec end;
>
> vm = create_vm(mode, vcpus, vcpu_memory_bytes);
>
> @@ -514,12 +510,11 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd,
> }
> }
>
> - pr_info("Total guest execution time: %lld.%.9lds\n",
> - (long long)(timespec_diff(start, end).tv_sec),
> - timespec_diff(start, end).tv_nsec);
> + ts_diff = timespec_sub(end, start);
> + pr_info("Total guest execution time: %ld.%.9lds\n",
> + ts_diff.tv_sec, ts_diff.tv_nsec);
> pr_info("Overall demand paging rate: %f pgs/sec\n",
> - guest_num_pages / ((double)timespec_diff(start, end).tv_sec +
> - (double)timespec_diff(start, end).tv_nsec / 100000000.0));
> + guest_num_pages / ((double)ts_diff.tv_sec + (double)ts_diff.tv_nsec / 100000000.0));
>
> ucall_uninit(vm);
> kvm_vm_free(vm);
> diff --git a/tools/testing/selftests/kvm/include/test_util.h b/tools/testing/selftests/kvm/include/test_util.h
> index f588ad1403f1..5eb01bf51b86 100644
> --- a/tools/testing/selftests/kvm/include/test_util.h
> +++ b/tools/testing/selftests/kvm/include/test_util.h
> @@ -61,7 +61,8 @@ void test_assert(bool exp, const char *exp_str,
> size_t parse_size(const char *size);
>
> int64_t timespec_to_ns(struct timespec ts);
> -struct timespec timespec_diff(struct timespec start, struct timespec end);
> struct timespec timespec_add_ns(struct timespec ts, int64_t ns);
> +struct timespec timespec_add(struct timespec ts1, struct timespec ts2);
> +struct timespec timespec_sub(struct timespec ts1, struct timespec ts2);
>
> #endif /* SELFTEST_KVM_TEST_UTIL_H */
> diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c
> index ee12c4b9ae05..689e97c27ee2 100644
> --- a/tools/testing/selftests/kvm/lib/test_util.c
> +++ b/tools/testing/selftests/kvm/lib/test_util.c
> @@ -56,36 +56,31 @@ int64_t timespec_to_ns(struct timespec ts)
> return (int64_t)ts.tv_nsec + 1000000000LL * (int64_t)ts.tv_sec;
> }
>
> -struct timespec timespec_diff(struct timespec start, struct timespec end)
> -{
> - struct timespec temp;
> -
> - if ((end.tv_nsec - start.tv_nsec) < 0) {
> - temp.tv_sec = end.tv_sec - start.tv_sec - 1;
> - temp.tv_nsec = 1000000000LL + end.tv_nsec - start.tv_nsec;
> - } else {
> - temp.tv_sec = end.tv_sec - start.tv_sec;
> - temp.tv_nsec = end.tv_nsec - start.tv_nsec;
> - }
> -
> - return temp;
> -}
> -
> struct timespec timespec_add_ns(struct timespec ts, int64_t ns)
> {
> struct timespec res;
>
> - res.tv_sec = ts.tv_sec;
> res.tv_nsec = ts.tv_nsec + ns;
> -
> - if (res.tv_nsec > 1000000000UL) {
> - res.tv_sec += 1;
> - res.tv_nsec -= 1000000000UL;
> - }
> + res.tv_sec = ts.tv_sec + res.tv_nsec / 1000000000LL;
> + res.tv_nsec %= 1000000000LL;
>
> return res;
> }
>
> +struct timespec timespec_add(struct timespec ts1, struct timespec ts2)
> +{
> + int64_t ns1 = timespec_to_ns(ts1);
> + int64_t ns2 = timespec_to_ns(ts2);
> + return timespec_add_ns((struct timespec){0}, ns1 + ns2);
> +}
> +
> +struct timespec timespec_sub(struct timespec ts1, struct timespec ts2)
> +{
> + int64_t ns1 = timespec_to_ns(ts1);
> + int64_t ns2 = timespec_to_ns(ts2);
> + return timespec_add_ns((struct timespec){0}, ns1 - ns2);
> +}
> +
> void print_skip(const char *fmt, ...)
> {
> va_list ap;
> diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c
> index 21990d653099..86f30eda0ae7 100644
> --- a/tools/testing/selftests/kvm/steal_time.c
> +++ b/tools/testing/selftests/kvm/steal_time.c
> @@ -242,7 +242,7 @@ static void *do_steal_time(void *arg)
>
> while (1) {
> clock_gettime(CLOCK_MONOTONIC, &ts);
> - if (ts.tv_sec > stop.tv_sec || ts.tv_nsec >= stop.tv_nsec)
> + if (timespec_to_ns(timespec_sub(ts, stop)) >= 0)
> break;
> }
>
>
