Commit f8ed349e authored by Alex Bennée's avatar Alex Bennée
Browse files

docs/devel: add "check-tcg" to testing.rst 



It was pointed out we haven't documented the check-tcg part of the
build system. Attempt to rectify that now.

Signed-off-by: default avatarAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: default avatarRichard Henderson <richard.henderson@linaro.org>
parent daa79d9a

docs/devel/testing.rst

+76 −0
Original line number Diff line number Diff line
@@ -266,6 +266,8 @@ another application on the host may have locked the file, possibly leading to a 
test failure.  If using such devices are explicitly desired, consider adding

``locking=off`` option to disable image locking.



.. _docker-ref:



Docker based tests

==================
@@ -799,3 +801,77 @@ And remove any package you want with:: 


If you've used ``make check-acceptance``, the Python virtual environment where

Avocado is installed will be cleaned up as part of ``make check-clean``.



Testing with "make check-tcg"

=============================



The check-tcg tests are intended for simple smoke tests of both

linux-user and softmmu TCG functionality. However to build test

programs for guest targets you need to have cross compilers available.

If your distribution supports cross compilers you can do something as

simple as::



  apt install gcc-aarch64-linux-gnu



The configure script will automatically pick up their presence.

Sometimes compilers have slightly odd names so the availability of

them can be prompted by passing in the appropriate configure option

for the architecture in question, for example::



  $(configure) --cross-cc-aarch64=aarch64-cc



There is also a ``--cross-cc-flags-ARCH`` flag in case additional

compiler flags are needed to build for a given target.



If you have the ability to run containers as the user you can also

take advantage of the build systems "Docker" support. It will then use

containers to build any test case for an enabled guest where there is

no system compiler available. See :ref: `_docker-ref` for details.



Running subset of tests

-----------------------



You can build the tests for one architecture::



  make build-tcg-tests-$TARGET



And run with::



  make run-tcg-tests-$TARGET



Adding ``V=1`` to the invocation will show the details of how to

invoke QEMU for the test which is useful for debugging tests.



TCG test dependencies

---------------------



The TCG tests are deliberately very light on dependencies and are

either totally bare with minimal gcc lib support (for softmmu tests)

or just glibc (for linux-user tests). This is because getting a cross

compiler to work with additional libraries can be challenging.



Other TCG Tests

---------------



There are a number of out-of-tree test suites that are used for more

extensive testing of processor features.



KVM Unit Tests

~~~~~~~~~~~~~~



The KVM unit tests are designed to run as a Guest OS under KVM but

there is no reason why they can't exercise the TCG as well. It

provides a minimal OS kernel with hooks for enabling the MMU as well

as reporting test results via a special device::



  https://git.kernel.org/pub/scm/virt/kvm/kvm-unit-tests.git



Linux Test Project

~~~~~~~~~~~~~~~~~~



The LTP is focused on exercising the syscall interface of a Linux

kernel. It checks that syscalls behave as documented and strives to

exercise as many corner cases as possible. It is a useful test suite

to run to exercise QEMU's linux-user code::



  https://linux-test-project.github.io/