Re: [PATCH 3/3] selftests/user_events: Add test cases when event is disabled

[Beau Belgrave <beaub@xxxxxxxxxxxxxxxxxxx>]

On Thu, Jun 08, 2023 at 09:15:54AM +0800, sunliming wrote:
> When user_events are disabled, it's write operation should be fail. Add
> this test cases.
> 
> Signed-off-by: sunliming <sunliming@xxxxxxxxxx>
> ---
>  tools/testing/selftests/user_events/ftrace_test.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/tools/testing/selftests/user_events/ftrace_test.c b/tools/testing/selftests/user_events/ftrace_test.c
> index d33bd31425db..d3240a97f23d 100644
> --- a/tools/testing/selftests/user_events/ftrace_test.c
> +++ b/tools/testing/selftests/user_events/ftrace_test.c
> @@ -297,6 +297,9 @@ TEST_F(user, write_events) {
>  	io[0].iov_base = &reg.write_index;
>  	io[0].iov_len = sizeof(reg.write_index);
>  
> +	/* Write should fail when event is not enabled */
> +	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
> +

We should also check errno value in this case. See my reply in the other
patch about -EFAULT vs -ENOENT in this case.

Thanks,
-Beau

>  	/* Enable event */
>  	self->enable_fd = open(enable_file, O_RDWR);
>  	ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1")))
> -- 
> 2.25.1