Re: [PATCH v3 6/8] selftests/mm: Make migration test robust to failure

[David Hildenbrand <david@redhat.com>]

On 24.07.23 10:25, Ryan Roberts wrote:
> The `migration` test currently has a number of robustness problems that
> cause it to hang and leak resources.
> 
> Timeout: There are 3 tests, which each previously ran for 60 seconds.
> However, the timeout in mm/settings for a single test binary was set to
> 45 seconds. So when run using run_kselftest.sh, the top level timeout
> would trigger before the test binary was finished. Solve this by meeting
> in the middle; each of the 3 tests now runs for 20 seconds (for a total
> of 60), and the top level timeout is set to 90 seconds.
> 
> Leaking child processes: the `shared_anon` test fork()s some children
> but then an ASSERT() fires before the test kills those children. The
> assert causes immediate exit of the parent and leaking of the children.
> Furthermore, if run using the run_kselftest.sh wrapper, the wrapper
> would get stuck waiting for those children to exit, which never happens.
> Solve this by setting the "parent death signal" to SIGHUP in the child,
> so that the child is killed automatically if the parent dies.
> 
> With these changes, the test binary now runs to completion on arm64,
> with 2 tests passing and the `shared_anon` test failing.
> 
> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
> ---

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Cheers,

David / dhildenb