Re: [dpdk-dev] [PATCH v2 3/3] app/test/meson: auto detect number of cores

[Aaron Conole <aconole@redhat.com>]

Bruce Richardson <bruce.richardson@intel.com> writes:

> On Fri, Apr 12, 2019 at 12:21:41PM -0400, Aaron Conole wrote:
>> The arguments being passed will cause failures on laptops that have,
>> for instance, 2 cores only.  Most of the tests don't require more
>> than a single core.  Some require multiple cores (but those tests
>> should be modified to 'SKIP' when the correct number of cores
>> aren't available).
>> 
>> The unit test results shouldn't be impacted by this change, but it
>> allows for a future enhancement to pass flags such as '--no-huge'.
>> 
>> Also include a fix to a reported issue with running on FreeBSD.
>> 
>> Signed-off-by: Aaron Conole <aconole@redhat.com>
>> Reviewed-by: David Marchand <david.marchand@redhat.com>
>> Acked-by: Luca Boccassi <bluca@debian.org>
>> ---
>> v2:
>> * Fix a spelling mistake
>> * Add support for FreeBSD
>> * Include a default fallback
>> * Use a more robust core-mask argument source (rather than lscpu)
>> 
>> Conflicts with http://patches.dpdk.org/patch/50850/
>> 
>>  app/test/meson.build | 35 ++++++++++++++++++++++++++++++++---
>>  1 file changed, 32 insertions(+), 3 deletions(-)
>> 
>> diff --git a/app/test/meson.build b/app/test/meson.build
>> index 867cc5863..5e056eb59 100644
>> --- a/app/test/meson.build
>> +++ b/app/test/meson.build
>> @@ -344,17 +344,43 @@ if get_option('tests')
>>  	timeout_seconds = 600
>>  	timeout_seconds_fast = 10
>>  
>> +	# Retrieve the number of CPU cores, defaulting to 4.
>> +	num_cores = '0-3'
>> +	if host_machine.system() == 'linux'
>> +		num_cores = run_command('cat',
>> +					'/sys/devices/system/cpu/present'
>> +				       ).stdout().strip()
>> +	elif host_machine.system() == 'freebsd'
>> +		snum_cores = run_command('/sbin/sysctl', '-n',
>> +					 'hw.ncpu').stdout().strip()
>> +		inum_cores = snum_cores.to_int() - 1
>> +                num_cores = '0-@0@'.format(inum_cores)
>> +	endif
>> +
>> +	num_cores_arg = '-l ' + num_cores
>> +
>> +	test_args = [num_cores_arg, '-n 4']
>
> This -n 4 parameter can be dropped. Four is the default setting IIRC.

For another patch.  I thought about doing it with this one, but I'd
rather keep the changes a little bit traceable.  If you think I should
resubmit with it dropped, I will.

> I also wonder are the parameters coming through to the app correctly,
> generally meson does not work well with parameters with spaces in them -
> I'd expect the "-l" and the num_cores values to be separated in the array.
> I also think num_cores_arg value could be dropped too.
>
> If it works though, I'm ok to keep as-is though.

It does work.  Actually, I needed to change because on some of the VM
setups (including the one used by Travis) the '-c f' arg errors because
it wants 4 cores, and only 2 exist.  Either way, this patch doesn't
change the spacing being passed with args :)

>>  	foreach arg : fast_parallel_test_names
>> -		test(arg, dpdk_test,
>> -			env : ['DPDK_TEST=' + arg],
>> -			args : ['-c f','-n 4', '--file-prefix=@0@'.format(arg)],
>> +		if host_machine.system() == 'linux'
>> +			test(arg, dpdk_test,
>> +				  env : ['DPDK_TEST=' + arg],
>> +				  args : test_args +
>> +					 ['--file-prefix=@0@'.format(arg)],
>> +			timeout : timeout_seconds_fast,
>> +			suite : 'fast-tests')
>> +		else
>> +			test(arg, dpdk_test,
>> +				env : ['DPDK_TEST=' + arg],
>> +				args : test_args,
>>  			timeout : timeout_seconds_fast,
>>  			suite : 'fast-tests')
>> +		endif
>>  	endforeach
>
> While this is needed now, I think in the medium term we should have the
> "file-prefix" flag being a warning rather than a hard-error on FreeBSD.
> [i.e. keep this, but we should fix it in 19.08 to be shorter]

Agreed.  Probably a good cleanup in the future.

> /Bruce