docs: Move the current CI .rst doc to docs/ci/ and link to it from .gitlab-ci.

I want the docs to be discoverable next to the code, and sphinx insists
that all docs are under the top-level docs dir (sigh).  We can't symlink
from that dir to .gitlab-ci because windows builds can't do symlinks, so
link back the other direction.

Reviewed-by: Eric Engestrom <[email protected]>
Reviewed-by: Erik Faye-Lund <[email protected]>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5510>

1 files changed, 76 insertions, 0 deletions

diff --git a/docs/ci/index.rst b/docs/ci/index.rst
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+Continuous Integration & Testing
+================================
+
+
+GitLab CI
+---------
+
+GitLab provides a convenient framework for running commands in response to git pushes.
+We use it to test merge requests (MRs) before merging them (pre-merge testing),
+as well as post-merge testing, for everything that hits ``master``
+(this is necessary because we still allow commits to be pushed outside of MRs,
+and even then the MR CI runs in the forked repository, which might have been
+modified and thus is unreliable).
+
+The CI runs a number of tests, from trivial build-testing to complex GPU rendering:
+
+- Build testing for a number of build systems, configurations and platforms
+- Sanity checks (``meson test`` & ``scons check``)
+- Some drivers (softpipe, llvmpipe, freedreno and panfrost) are also tested
+  using `VK-GL-CTS <https://github.com/KhronosGroup/VK-GL-CTS>`__
+
+A typical run takes between 20 and 30 minutes, although it can go up very quickly
+if the GitLab runners are overwhelmed, which happens sometimes. When it does happen,
+not much can be done besides waiting it out, or cancel it.
+
+Due to limited resources, we currently do not run the CI automatically
+on every push; instead, we only run it automatically once the MR has
+been assigned to ``Marge``, our merge bot.
+
+If you're interested in the details, the main configuration file is ``.gitlab-ci.yml``,
+and it references a number of other files in ``.gitlab-ci/``.
+
+If the GitLab CI doesn't seem to be running on your fork (or MRs, as they run
+in the context of your fork), you should check the "Settings" of your fork.
+Under "CI / CD" → "General pipelines", make sure "Custom CI config path" is
+empty (or set to the default ``.gitlab-ci.yml``), and that the
+"Public pipelines" box is checked.
+
+If you're having issues with the GitLab CI, your best bet is to ask
+about it on ``#freedesktop`` on Freenode and tag `Daniel Stone
+<https://gitlab.freedesktop.org/daniels>`__ (``daniels`` on IRC) or
+`Eric Anholt <https://gitlab.freedesktop.org/anholt>`__ (``anholt`` on
+IRC).
+
+
+Intel CI
+--------
+
+The Intel CI is not yet integrated into the GitLab CI.
+For now, special access must be manually given (file a issue in
+`the Intel CI configuration repo <https://gitlab.freedesktop.org/Mesa_CI/mesa_jenkins>`__
+if you think you or Mesa would benefit from you having access to the Intel CI).
+Results can be seen on `mesa-ci.01.org <https://mesa-ci.01.org>`__
+if you are *not* an Intel employee, but if you are you
+can access a better interface on
+`mesa-ci-results.jf.intel.com <http://mesa-ci-results.jf.intel.com>`__.
+
+The Intel CI runs a much larger array of tests, on a number of generations
+of Intel hardware and on multiple platforms (x11, wayland, drm & android),
+with the purpose of detecting regressions.
+Tests include
+`Crucible <https://gitlab.freedesktop.org/mesa/crucible>`__,
+`VK-GL-CTS <https://github.com/KhronosGroup/VK-GL-CTS>`__,
+`dEQP <https://android.googlesource.com/platform/external/deqp>`__,
+`Piglit <https://gitlab.freedesktop.org/mesa/piglit>`__,
+`Skia <https://skia.googlesource.com/skia>`__,
+`VkRunner <https://github.com/Igalia/vkrunner>`__,
+`WebGL <https://github.com/KhronosGroup/WebGL>`__,
+and a few other tools.
+A typical run takes between 30 minutes and an hour.
+
+If you're having issues with the Intel CI, your best bet is to ask about
+it on ``#dri-devel`` on Freenode and tag `Clayton Craft
+<https://gitlab.freedesktop.org/craftyguy>`__ (``craftyguy`` on IRC) or
+`Nico Cortes <https://gitlab.freedesktop.org/ngcortes>`__ (``ngcortes``
+on IRC).