> CSV output example:
> 
> 1.20,msec,task-clock:u,1204272,100.00,0.697,CPUs utilized
> 0,,context-switches:u,1204272,100.00,0.000,/sec
> 0,,cpu-migrations:u,1204272,100.00,0.000,/sec
> 70,,page-faults:u,1204272,100.00,58.126,K/sec

The difficult part of such changes to perf stat is that it has
so many different output modes that all need to be tested.
Unfortunately the unit tests in perf test are not really
enough for it.

I have an older script (attached) that tests a lot of these outputs. It just
exercises them, you still need to check the output manually

Can you check that all these modes work correctly both
with and without json?

-Andi