Re: [PATCH v2] RFC perf test 14 add platform dependency

[Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>]

On 06/20/2017 03:40 AM, Arnaldo Carvalho de Melo wrote:
> Em Mon, Jun 19, 2017 at 10:59:44PM +0200, Jiri Olsa escreveu:
>> On Tue, Jun 13, 2017 at 11:09:37AM +0200, Thomas Richter wrote:
>>> This is a proposal to add platform dependency into the
>>> test case 14 (perf_event_attr). It is based on a suggestion from
>>> Jiri Olsa.
>>> Add a new optional attribute named 'machine' in the [config] section
>>> of the test case file. It is a comma separated list of architecture
>>> names this test can be executed on. For example:
>>>
>>> machine = x86_64,alpha,ppc
>>
>> 'arch' sounds better to me, but machine is ok I guess
> 
> Agreed, for consistency with other places, like in struct machine, that
> represents virtual and host 'machines' that have an 'arch', etc.
> 
> So better to rename "machine" above to "arch".
> 

Ok lets rename it to arch.

>>> If this attribute is missing the test is executed on any platform.
>>> This does not break the current setup.
>>> The values listed for this attribute should be identical to
>>> uname -m output.
>>> If the list starts with an exclamation mark (!) the comparison is
>>> inverted, for example for
>>>
>>> machine = !s390x,ppc
>>>
>>> the test is not executed on s390x or ppc platforms.
>>> The exclamation mark must be at the beginnning of the list.
>>
>> could that be per arch? this made me think that it's not s390 and it IS for ppc
> 
> yeah, having the ! affect just the arch right after it looks more
> flexible and clear.
> 

Does this really have any benefit? Assume
arch = !s390x,ppc

I will scan the list from left to right and the first match wins.
Checking the first word in the list determines
this test is executed on anything but s390x. So the 2nd word in the
list (ppc) is useless. Specifying more architectures makes only sense
when you negate them such as
arch = !s390x,!ppc

That is the reason why I ended up with the original proposal.
Any suggestions?

-- 
Thomas Richter, Dept 3303, IBM LTC Boeblingen Germany
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