[Intel-gfx] [igt] Making the test-suite easier to run

[Damien Lespiau]

The objective of this series is to make the test-suite easier to run by
embedding a copy a piglit and providing porcelain on top of it in the form of a
makefile target. Beside python, there's no external dependency to run the test
suite after this series.

The provided makefile target runs the full test suite. I'm still interested in
providing, as a follow-up of this work, shorcuts for subsets of the testsuite
that can be useful for developpers, subset what we would maintain in tree. For
instance:
  - tests selected by topic: running gem_.* Vs kms_.* Vs pm_.* (or maybe when
    running, say, gt tests, exlude ^kms_.* ^pm_.* so we still still a lot of
    the other tests (core_, drm_, ...)
  - quick subtests (where we disable long running stress, race, ... tests)

patches 21-23 are something a bit different, try to pave the way for quick
runs (by really the first tiny step).

The README has been updated and I copy/paste it here the documentation for what
would be the new way to run tests:

        After having compiled the tests, one can run the test-suite with:

        $ sudo make run-tests

        "make run-tests" create a $date-piglit-results.$n directory with the
        results of the run. More specifically:
          - $date-piglit-results.$n/main JSON file with the test results
          - $date-piglit-results.$n/html/index.html HTML summary of the run

        Where $date is the date formated with `date +%Y%m%d` and $n the nth run
        of the day.

        PIGLIT_FLAGS can be used to give options to the underlying piglit
        runner. For instance, to exclude test matching '^kms_':

        $ sudo make run-tests PIGLIT_FLAGS="-x ^kms_"

        For the list of piglit options, run:

        $ ./piglit/piglit-run.py -h

        Another useful feature is to be able to resume an interrupted run. To
        do that, make run-tests needs to know which run we are talking about:

        $ sudo make run-tests RESUME=$date-piglit-results.$n

        or, more succinctly:

        $ sudo make run-tests R=$date-piglit-results.$n

        It's possible to combine PIGLIT_FLAGS and RESUME. This is useful to
        resume runs where a specific test deterministically hang the machine:

        $ sudo make run-tests PIGLIT_FLAGS="-x drv_module_reload" R=$date-piglit-results.$n

HTH,

-- 
Damien