Re: [PATCH i-g-t 1/2] tests/intel/xe_oa: Do not discard single reports in oa-formats

["Dixit, Ashutosh" <ashutosh.dixit@intel.com>]

On Tue, 04 Mar 2025 16:57:15 -0800, Umesh Nerlige Ramappa wrote:
>
> Internally the test is expecting a single read call to return at least
> two reports. If two reports are not read, the logic retries from the
> beginning. This can easily fail if each read just returns one report.

OK, you mean 1000 reads each returning just one report.

> In essence, many reports are available, but the logic causes test to
> fail.  Instead, count and use every report read when waiting for two
> reports to be available.
>
> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> ---
>  tests/intel/xe_oa.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/tests/intel/xe_oa.c b/tests/intel/xe_oa.c
> index dd71683928bd..e5744d830d39 100644
> --- a/tests/intel/xe_oa.c
> +++ b/tests/intel/xe_oa.c
> @@ -1314,13 +1314,14 @@ read_2_oa_reports(int format_id,
>	int max_reports = default_oa_buffer_size / format_size;
>	int buf_size = format_size * max_reports * 1.5;
>	uint8_t *buf = malloc(buf_size);
> +	ssize_t len = 0;
>	int n = 0;
>
>	for (int i = 0; i < 1000; i++) {
>		u32 oa_status = 0;
> -		ssize_t len;
> +		int ret;
>
> -		while ((len = read(stream_fd, buf, buf_size)) < 0 && errno == EINTR)
> +		while ((ret = read(stream_fd, buf + len, buf_size)) < 0 && errno == EINTR)

Probably never hit this but maybe 'buf_size - len' ? Otherwise:

Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>

>			;
>		if (errno == EIO) {
>			oa_status = get_stream_status(stream_fd);
> @@ -1328,9 +1329,10 @@ read_2_oa_reports(int format_id,
>			continue;
>		}
>
> -		igt_assert(len > 0);
> -		igt_debug("read %d bytes\n", (int)len);
> +		igt_assert(ret > 0);
> +		igt_debug("read %d bytes\n", (int)ret);
>
> +		len += ret;
>		/* Need at least 2 reports */
>		if (len < 2 * format_size)
>			continue;
> --
> 2.45.2
>