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

[Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>]

On Tue, Mar 04, 2025 at 08:56:20PM -0800, Dixit, Ashutosh wrote:
>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.

Right, I will add that in the description.

>
>> 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:

Yeah, but I think I will still change that to 'buf_size - len'.

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

Thanks,
Umesh
>
>>			;
>>		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
>>