[libcamera-devel] [PATCH 2/2] test: camera: Camera reconfiguration and fd-leak test

[Kieran Bingham]

Hi Laurent,

On 17/08/2021 14:04, Laurent Pinchart wrote:
> Hi Umang,
> >> +	pid_t findProxyPid()
>> +	{
>> +		string proxyPid;
>> +		string proxyName(kIpaProxyName_);
>> +		DIR *dir;
>> +		struct dirent *ptr;
>> +
>> +		dir = opendir("/proc");
>> +		while((ptr = readdir(dir)) != nullptr) {
>> +			if(ptr->d_type != DT_DIR)
>> +				continue;
>> +
>> +			string pname("/proc/" + string(ptr->d_name) + "/comm");
>> +			if(File::exists(pname.c_str())) {
> 
> Missing space.
> 
> I may have missed it, but I haven't seen an answer to my review of the
> previous version that proposed checking the number of open file
> descriptors in the VIMC IPA module itself. That would test for fd leaks
> in all tests using vimc, and wouldn't require finding child processes.


I presume this would just fire an ASSERT() if it was detected. (Unless
you have another way to report the failure up to the test?)

I'm a bit weary that this would be hard to track down when it fires as
the failure would occur in a process which we don't (easily) get logs
from. The failure condition might get a bit 'lost'.

The assert would cause the IPA to 'crash', and the tests would fail -
but they would look like they were failing because the IPA had
'disappeared' and may not be obvious to diagnose..


I wonder if we need to tackle how we log from isolated processes already
... :-S


I guess the alternative is to have some extended interface callbacks
from the IPA to allow it to message the VIMC pipeline handler to report
something ... and ... cause a failure and shutdown on the pipeline side ?

--
Kieran