.. _tests-integration-testing-teuthology-kernel:

Integration Tests for Kernel Development
========================================


.. _kernel-cephfs:

CephFS
------

The ``fs`` suite runs various kernels as described by the `kernel YAML
fragments`_. These are symbolically linked by other sub-suites under the ``fs``
suite.

The matrix of fragments allows for testing the following configurations:

* The "stock" kernel on RHEL 8 (i.e. the kernel that ships with it).

* The `testing branch`_ by the kernel development team which represents the
  patches undergoing active testing. These patches may or may not be in the next
  upstream kernel release and include a mix of CephFS or kRBD changes. For the
  testing kernel, we test with whatever distributions are specified by the
  sub-suite. For example, the ``fs:functional`` sub-suite uses a random selection
  of the `supported random distros`_.




Testing custom kernels
----------------------

If you have a kernel branch on `ceph-client.git`_ and have built it using
shaman, then you can also test that easily by specifying an override for the
kernel. This is done via a YAML fragment passed to the ``teuthology-suite``
command:

::

    $ cat custom-kernel.yaml
    overrides:
      kernel:
        branch: for-linus

This specifies an override for the kernel branch specified in the suite's
matrix. You can also specify an override as a tag or SHA1 for the ``kernel``
task. When overriding the kernel, you should reduce the selection of jobs as
the matrix will include a number of kernel configurations you won't care to
test, as mentioned in the :ref:`kernel-cephfs` section; the override YAML will
apply to all configurations of the kernel so it will result in duplicate tests.
The command to run tests will look like:

.. prompt:: bash $

    teuthology-suite ... --suite fs --filter k-testing custom-kernel.yaml

Where ``...`` indicates other typical options that are normally specified when
running ``teuthology-suite``. The important filter ``--filter k-testing``
will limit the selection of jobs to those using the ``testing`` branch of the
kernel (see the `k-testing.yaml`_ file). So you'll only select jobs using the
kernel client with the ``testing`` branch. Your custom YAML file,
``custom-kernel.yaml``, will further override the ``testing`` branch to use
whatever you specify.



.. _kernel YAML fragments: https://github.com/ceph/ceph/tree/63f84c50e0851d456fc38b3330945c54162dd544/qa/cephfs/mount/kclient/overrides/distro
.. _ceph-client.git: https://github.com/ceph/ceph-client/tree/testing
.. _testing branch: https://github.com/ceph/ceph-client/tree/testing
.. _supported random distros: https://github.com/ceph/ceph/blob/63f84c50e0851d456fc38b3330945c54162dd544/qa/suites/fs/functional/distro
.. _k-testing.yaml: https://github.com/ceph/ceph/blob/63f84c50e0851d456fc38b3330945c54162dd544/qa/cephfs/mount/kclient/overrides/distro/testing/k-testing.yaml