Re: [PATCH] perf stat: fix cvs output format

[Cong Wang]

On Tue, Mar 6, 2018 at 9:00 AM, Andi Kleen <ak@xxxxxxxxxxxxxxx> wrote:
> On Mon, Mar 05, 2018 at 10:43:53PM -0800, Cong Wang wrote:
>> From: Ilya Pronin <ipronin@xxxxxxxxxxx>
>>
>> When printing stats in CSV mode, perf stat appends extra CSV
>> separators when counter is not supported:
>>
>> <not supported>,,L1-dcache-store-misses,mesos/bd442f34-2b4a-47df-b966-9b281f9f56fc,0,100.00,,,,
>>
>> which causes a failure of parsing fields. The numbers of separators
>
> Causes failure in what?

Failed to know how many fields in that line, clearly there are less
separators when it is supported.


>
>> is fixed for each line, no matter supported or not supported.
>
> I don't think they're extra fields, there are cases where they can be filled out
> for variance, metricvalue, unit. And other code in perf too uses empty
> fields when something is not available.

Are you saying there should be more fields when it is not supported?

Here is the output from your own commit:

      423470,,stalled-cycles-frontend,509102,100.00,65.69,frontend cycles idle
      <not supported>,,stalled-cycles-backend,0,100.00,,,,

so line 1 has 7 fields, line 2 has 9 fields, and this is expected?