docs/devel: rationalise unstable gitlab tests under FLAKY_TESTS

It doesn't make sense to have two classes of flaky tests. While it may
take the constrained environment of CI to trigger failures easily it
doesn't mean they don't occasionally happen on developer machines. As
CI is the gating factor to passing there is no point developers
running the tests locally anyway unless they are trying to fix things.

While we are at it update the language in the docs to discourage the
QEMU_TEST_FLAKY_TESTS becoming a permanent solution.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231201093633.2551497-3-alex.bennee@linaro.org>

docs/devel/testing.rst

@@ -1371,23 +1371,32 @@ conditions. For example, tests that take longer to execute when QEMU is
 compiled with debug flags. Therefore, the ``AVOCADO_TIMEOUT_EXPECTED`` variable
 has been used to determine whether those tests should run or not.
 
-GITLAB_CI
-^^^^^^^^^
-A number of tests are flagged to not run on the GitLab CI. Usually because
-they proved to the flaky or there are constraints on the CI environment which
-would make them fail. If you encounter a similar situation then use that
-variable as shown on the code snippet below to skip the test:
+QEMU_TEST_FLAKY_TESTS
+^^^^^^^^^^^^^^^^^^^^^
+Some tests are not working reliably and thus are disabled by default.
+This includes tests that don't run reliably on GitLab's CI which
+usually expose real issues that are rarely seen on developer machines
+due to the constraints of the CI environment. If you encounter a
+similar situation then raise a bug and then mark the test as shown on
+the code snippet below:
 
 .. code::
 
-  @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+  # See https://gitlab.com/qemu-project/qemu/-/issues/nnnn
+  @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
   def test(self):
       do_something()
 
-QEMU_TEST_FLAKY_TESTS
-^^^^^^^^^^^^^^^^^^^^^
-Some tests are not working reliably and thus are disabled by default.
-Set this environment variable to enable them.
+Tests should not live in this state forever and should either be fixed
+or eventually removed.
+
+To run such tests locally you will need to set the environment
+variable. For example:
+
+.. code::
+
+   env QEMU_TEST_FLAKY_TESTS=1 ./pyvenv/bin/avocado run \
+      tests/avocado/boot_linux.py:BootLinuxPPC64.test_pseries_tcg
 
 Uninstalling Avocado
 ~~~~~~~~~~~~~~~~~~~~

tests/avocado/boot_linux.py

@@ -12,7 +12,7 @@
 
 from avocado_qemu import LinuxTest, BUILD_DIR
 
-from avocado import skipIf
+from avocado import skipUnless
 
 
 class BootLinuxX8664(LinuxTest):
@@ -93,7 +93,8 @@ class BootLinuxPPC64(LinuxTest):
 
     timeout = 360
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_pseries_tcg(self):
         """
         :avocado: tags=machine:pseries
@@ -111,7 +112,8 @@ class BootLinuxS390X(LinuxTest):
 
     timeout = 240
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_s390_ccw_virtio_tcg(self):
         """
         :avocado: tags=machine:s390-ccw-virtio

tests/avocado/boot_linux_console.py

@@ -15,7 +15,7 @@
 
 from avocado import skip
 from avocado import skipUnless
-from avocado import skipIf
+from avocado import skipUnless
 from avocado_qemu import QemuSystemTest
 from avocado_qemu import exec_command
 from avocado_qemu import exec_command_and_wait_for_pattern
@@ -1419,7 +1419,8 @@ def test_ppc_mac99(self):
     # This test has a 6-10% failure rate on various hosts that look
     # like issues with a buggy kernel. As a result we don't want it
     # gating releases on Gitlab.
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_sh4_r2d(self):
         """
         :avocado: tags=arch:sh4

tests/avocado/intel_iommu.py

@@ -9,10 +9,11 @@
 # later.  See the COPYING file in the top-level directory.
 import os
 
-from avocado import skipIf
+from avocado import skipUnless
 from avocado_qemu import LinuxTest
 
-@skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+@skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
 class IntelIOMMU(LinuxTest):
     """
     :avocado: tags=arch:x86_64

tests/avocado/linux_initrd.py

@@ -13,7 +13,7 @@
 import tempfile
 
 from avocado_qemu import QemuSystemTest
-from avocado import skipIf
+from avocado import skipUnless
 
 
 class LinuxInitrd(QemuSystemTest):
@@ -53,7 +53,8 @@ def test_with_2gib_file_should_exit_error_msg_with_linux_v3_6(self):
                 max_size + 1)
             self.assertRegex(self.vm.get_log(), expected_msg)
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_with_2gib_file_should_work_with_linux_v4_16(self):
         """
         QEMU has supported up to 4 GiB initrd for recent kernel

tests/avocado/machine_aspeed.py

@@ -18,7 +18,7 @@
 from avocado_qemu import interrupt_interactive_console_until_pattern
 from avocado_qemu import has_cmd
 from avocado.utils import archive
-from avocado import skipIf
+from avocado import skipUnless
 from avocado import skipUnless
 
 
@@ -311,7 +311,8 @@ def do_test_arm_aspeed_sdk_start(self, image):
             self, 'boot', '## Loading kernel from FIT Image')
         self.wait_for_console_pattern('Starting kernel ...')
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_arm_ast2500_evb_sdk(self):
         """
         :avocado: tags=arch:arm
@@ -329,7 +330,8 @@ def test_arm_ast2500_evb_sdk(self):
             self.workdir + '/ast2500-default/image-bmc')
         self.wait_for_console_pattern('nodistro.0 ast2500-default ttyS4')
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_arm_ast2600_evb_sdk(self):
         """
         :avocado: tags=arch:arm

tests/avocado/machine_mips_malta.py

@@ -11,7 +11,7 @@
 import gzip
 import logging
 
-from avocado import skipIf
+from avocado import skipUnless
 from avocado import skipUnless
 from avocado.utils import archive
 from avocado_qemu import QemuSystemTest
@@ -101,7 +101,8 @@ def test_mips_malta_i6400_framebuffer_logo_1core(self):
         """
         self.do_test_i6400_framebuffer_logo(1)
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_mips_malta_i6400_framebuffer_logo_7cores(self):
         """
         :avocado: tags=arch:mips64el
@@ -111,7 +112,8 @@ def test_mips_malta_i6400_framebuffer_logo_7cores(self):
         """
         self.do_test_i6400_framebuffer_logo(7)
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_mips_malta_i6400_framebuffer_logo_8cores(self):
         """
         :avocado: tags=arch:mips64el

tests/avocado/machine_rx_gdbsim.py

@@ -10,7 +10,7 @@
 
 import os
 
-from avocado import skipIf
+from avocado import skipUnless
 from avocado_qemu import QemuSystemTest
 from avocado_qemu import exec_command_and_wait_for_pattern
 from avocado_qemu import wait_for_console_pattern
@@ -22,7 +22,8 @@ class RxGdbSimMachine(QemuSystemTest):
     timeout = 30
     KERNEL_COMMON_COMMAND_LINE = 'printk.time=0 '
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_uboot(self):
         """
         U-Boot and checks that the console is operational.
@@ -46,7 +47,8 @@ def test_uboot(self):
         # FIXME limit baudrate on chardev, else we type too fast
         #exec_command_and_wait_for_pattern(self, 'version', gcc_version)
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_linux_sash(self):
         """
         Boots a Linux kernel and checks that the console is operational.

tests/avocado/machine_s390_ccw_virtio.py

@@ -12,7 +12,7 @@
 import os
 import tempfile
 
-from avocado import skipIf
+from avocado import skipUnless
 from avocado_qemu import QemuSystemTest
 from avocado_qemu import exec_command_and_wait_for_pattern
 from avocado_qemu import wait_for_console_pattern

tests/avocado/replay_kernel.py

@@ -15,7 +15,7 @@
 import time
 
 from avocado import skip
-from avocado import skipIf
+from avocado import skipUnless
 from avocado import skipUnless
 from avocado_qemu import wait_for_console_pattern
 from avocado.utils import archive
@@ -82,6 +82,7 @@ def run_rr(self, kernel_path, kernel_command_line, console_pattern,
 
 class ReplayKernelNormal(ReplayKernelBase):
 
+    # See https://gitlab.com/qemu-project/qemu/-/issues/2010
     @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test sometimes gets stuck')
     def test_x86_64_pc(self):
         """
@@ -179,7 +180,8 @@ def test_arm_virt(self):
 
         self.run_rr(kernel_path, kernel_command_line, console_pattern, shift=1)
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_arm_cubieboard_initrd(self):
         """
         :avocado: tags=arch:arm

tests/avocado/reverse_debugging.py

@@ -10,7 +10,7 @@
 import os
 import logging
 
-from avocado import skipIf
+from avocado import skipUnless
 from avocado_qemu import BUILD_DIR
 from avocado.utils import datadrainer
 from avocado.utils import gdb
@@ -206,7 +206,8 @@ def get_pc(self, g):
             + self.get_reg_le(g, self.REG_CS) * 0x10
 
     # unidentified gitlab timeout problem
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_x86_64_pc(self):
         """
         :avocado: tags=arch:x86_64
@@ -223,7 +224,8 @@ class ReverseDebugging_AArch64(ReverseDebugging):
     REG_PC = 32
 
     # unidentified gitlab timeout problem
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_aarch64_virt(self):
         """
         :avocado: tags=arch:aarch64
@@ -247,7 +249,8 @@ class ReverseDebugging_ppc64(ReverseDebugging):
     REG_PC = 0x40
 
     # unidentified gitlab timeout problem
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_ppc64_pseries(self):
         """
         :avocado: tags=arch:ppc64
@@ -260,7 +263,8 @@ def test_ppc64_pseries(self):
         self.reverse_debugging()
 
     # See https://gitlab.com/qemu-project/qemu/-/issues/1992
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_ppc64_powernv(self):
         """
         :avocado: tags=arch:ppc64

tests/avocado/smmu.py

@@ -9,10 +9,11 @@
 # later.  See the COPYING file in the top-level directory.
 import os
 
-from avocado import skipIf
+from avocado import skipUnless
 from avocado_qemu import LinuxTest, BUILD_DIR
 
-@skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+@skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
 class SMMU(LinuxTest):
     """
     :avocado: tags=accel:kvm

tests/avocado/tuxrun_baselines.py

@@ -13,7 +13,7 @@
 import time
 import tempfile
 
-from avocado import skip, skipIf
+from avocado import skip, skipUnless
 from avocado_qemu import QemuSystemTest
 from avocado_qemu import exec_command, exec_command_and_wait_for_pattern
 from avocado_qemu import wait_for_console_pattern
@@ -551,7 +551,7 @@ def test_s390(self):
                            haltmsg="Requesting system halt")
 
     # Note: some segfaults caused by unaligned userspace access
-    @skipIf(os.getenv('GITLAB_CI'), 'Skipping unstable test on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
     def test_sh4(self):
         """
         :avocado: tags=arch:sh4