Merge branch 'wip/apinheiro/memory-barriers' into 'master'

Merge branch 'wip/apinheiro/memory-barriers' into 'master'

    Extra memory barriers needed on different tests

    We found several tests to consistently fail or to be flaky (not always failing/passing) on Intel Skylake GT2 model. Those get solved adding memory barriers. Those memory barriers are convenient as could prevent the tests failing on other hw.

    The branch includes 4 new commits, to make easier the review, but I think that they can be squashed without problems.

    See merge request !108

Change-Id: I4ec91df6c1d8721eee18f9aa0223d3c5ba6465ef