[PATCH 2/2] selftests/powerpc: Add perf breakpoint test

[Michael Neuling]

On Thu, 2018-05-24 at 20:30 +1000, Michael Ellerman wrote:
> Michael Neuling <mikey at neuling.org> writes:
> 
> > This tests perf hardware breakpoints (ie PERF_TYPE_BREAKPOINT) on
> > powerpc.
> 
> This doesn't work for me on a P8 guest:
> 
>   test: perf-hwbreak
>   tags: git_version:bb5602e
>   !! killing perf-hwbreak
>   !! child died by signal 15
>   failure: perf-hwbreak
> 
> 
> That means the harness killed it after 2 minutes.
> 
> Sometimes it gets further:
> 
>   test: perf-hwbreak
>   tags: git_version:v4.17-rc3-109-gbb20240fb508
>   threads=16 loops=1048576 scalar test
>   !! killing perf-hwbreak
>   !! child died by signal 15
>   failure: perf-hwbreak
> 
> 
> Do we just need to bump the timeout up, or is something going wrong
> here?

Yeah, sorry my bad.  The test was trying to randomly test all the combinations.
 
I've rewritten it now to explicitly test all the combinations. This gives it a
more consistent runtime. I do randomly vary the loop count but this is only a
small variation (~10%) to avoid using a count from a previous test.

Mikey