Re: [PATCH v4 11/11] KVM: selftests: Enable tunning of err_margin_us in arch timer test

Marc Zyngier
2023-12-19T18:22:48Z

On Tue, 12 Dec 2023 09:31:20 +0000,
Haibo Xu <haibo1.xu@intel.com> wrote:
> > @@ -216,6 +221,9 @@ static bool parse_args(int argc, char *argv[])
> case 'm':
> test_args.migration_freq_ms = atoi_non_negative("Frequency", optarg);
> break;
> + case 'e':
> + test_args.timer_err_margin_us = atoi_non_negative("Error Margin", optarg);
> + break;

So your error margin is always unsigned...

> case 'o':
> test_args.counter_offset = strtol(optarg, NULL, 0);
> test_args.reserved = 0;
> diff --git a/tools/testing/selftests/kvm/include/timer_test.h b/tools/testing/selftests/kvm/include/timer_test.h
> index 968257b893a7..b1d405e7157d 100644
> --- a/tools/testing/selftests/kvm/include/timer_test.h
> +++ b/tools/testing/selftests/kvm/include/timer_test.h
> @@ -22,6 +22,7 @@ struct test_args {
> int nr_iter;
> int timer_period_ms;
> int migration_freq_ms;
> + int timer_err_margin_us;

... except that you are storing it as a signed value. Some consistency
wouldn't hurt, really, and would avoid issues when passing large
values.

M.

--
Without deviation from the norm, progress is not possible.