Re: [PATCH v10 7/8] hugetlb_cgroup: Add hugetlb_cgroup reservation tests

[David Rientjes]

On Thu, 23 Jan 2020, Sandipan Das wrote:

> > The tests use both shared and private mapped hugetlb memory, and
> > monitors the hugetlb usage counter as well as the hugetlb reservation
> > counter. They test different configurations such as hugetlb memory usage
> > via hugetlbfs, or MAP_HUGETLB, or shmget/shmat, and with and without
> > MAP_POPULATE.
> > 
> > Also add test for hugetlb reservation reparenting, since this is
> > a subtle issue.
> > 
> > Signed-off-by: Mina Almasry <almasrymina@xxxxxxxxxx>
> > 
> 
> For powerpc64, either 16MB/16GB or 2MB/1GB huge pages are supported depending
> on the MMU type (Hash or Radix). I was just running these tests on a powerpc64
> system with Hash MMU and ran into problems because the tests assume that the
> hugepage size is always 2MB. Can you determine the huge page size at runtime?
> 

I assume this is only testing failures of the tools/testing/selftests 
additions that hardcode 2MB paths and not a kernel problem?  In other 
words, you can still boot, reserve, alloc, and free hugetlb pages on ppc 
after this patchset without using the selftests?