Add stress test for attaching and detaching multiple core devices.

Signed-off-by: Katarzyna Lapinska <katarzyna.lapinska@intel.com>

test/functional/tests/stress/test_stress_attach_detach.py

@@ -0,0 +1,53 @@
+#
+# Copyright(c) 2020 Intel Corporation
+# SPDX-License-Identifier: BSD-3-Clause-Clear
+#
+
+import pytest
+import random
+
+from api.cas import casadm
+from core.test_run import TestRun
+from storage_devices.disk import DiskTypeSet, DiskType, DiskTypeLowerThan
+from test_utils.size import Size, Unit
+
+
+@pytest.mark.require_disk("cache", DiskTypeSet([DiskType.optane, DiskType.nand]))
+@pytest.mark.require_disk("core", DiskTypeLowerThan("cache"))
+def test_stress_attach_detach():
+    """
+        title: Stress test for attaching and detaching multiple core devices.
+        description: |
+          Validate the ability of CAS to attach and detach core devices using script commands.
+        pass_criteria:
+          - No system crash.
+          - Core devices are successfully attached and detached.
+    """
+    iterations_number = 50
+
+    with TestRun.step("Prepare devices."):
+        cache_disk = TestRun.disks['cache']
+        cache_disk.create_partitions([Size(100, Unit.MebiByte)])
+        cache_part = cache_disk.partitions[0]
+
+        core_disk = TestRun.disks['core']
+        core_disk.create_partitions([Size(5, Unit.GibiByte)] * 8)
+        core_devices = core_disk.partitions
+
+    with TestRun.step("Start cache."):
+        cache = casadm.start_cache(cache_part)
+        cores = []
+        for dev in core_devices:
+            cores.append(cache.add_core(dev))
+
+    with TestRun.step("Attach and detach core devices in a loop."):
+        for _ in TestRun.iteration(range(0, iterations_number)):
+            TestRun.LOGGER.info("Detaching all core devices.")
+            for core in cores:
+                casadm.detach_core(cache.cache_id, core.core_id)
+
+            random.shuffle(cores)
+
+            TestRun.LOGGER.info("Attaching all core devices.")
+            for core in cores:
+                casadm.try_add(core.core_device, cache.cache_id, core.core_id)