add case for discard memory content

   VIRT-298033: Discard memory content
Signed-off-by: nanli <[email protected]>

libvirt/tests/cfg/memory/memory_backing/discard_memory_content_setting.cfg

@@ -0,0 +1,49 @@
+- memory.backing.discard:
+    type = discard_memory_content_setting
+    start_vm = "no"
+    set_pagesize = 2048
+    set_pagenum = 1024
+    numa_mem = 2097152
+    qemu_line = '"discard-data":%s'
+    variants source:
+        - file:
+            source_type = 'file'
+            source_attr = "'source_type':'${source_type}'"
+            source_path = {'element_attrs': ['./memoryBacking/source/[@type="${source_type}"]']}
+        - anonymous:
+            source_type = 'anonymous'
+            source_attr = "'source_type':'${source_type}'"
+            source_path = {'element_attrs': ['./memoryBacking/source/[@type="${source_type}"]']}
+        - memfd:
+            source_type = 'memfd'
+            source_attr = "'source_type':'${source_type}'"
+            source_path = {'element_attrs': ['./memoryBacking/source/[@type="${source_type}"]']}
+        - hugepaged_file:
+            source_type = 'hugepage'
+            hugepages_attr = "'hugepages': {}"
+            hugepages_path = {'element_attrs': ['./memoryBacking/hugepages']}
+    variants mem_discard:
+        - mem_discard_yes:
+            mem_discard_attr = "'discard':'yes'"
+            mem_discard_path = {'element_attrs': ["./memoryBacking/discard"]}
+        - mem_discard_not_defined:
+    variants numa_discard:
+        - numa_discard_yes:
+            discard = "yes"
+            numa_attrs = {'vcpu': 4,'cpu': {'numa_cell': [{'id': '0', 'cpus': '0-3', 'memory': '${numa_mem}', 'unit': 'KiB', 'discard':'${discard}'}]}}
+            numa_path = {'element_attrs': ['./cpu/numa/cell/[@discard="${discard}"]']}
+        - numa_discard_no:
+            discard = "no"
+            numa_attrs = {'vcpu': 4,'cpu': {'numa_cell': [{'id': '0', 'cpus': '0-3', 'memory': '${numa_mem}', 'unit': 'KiB', 'discard':'${discard}'}]}}
+            numa_path = {'element_attrs': ['./cpu/numa/cell/[@discard="${discard}"]']}
+        - numa_discard_not_defined:
+            numa_attrs = {'vcpu': 4,'cpu': {'numa_cell': [{'id': '0', 'cpus': '0-3', 'memory': '${numa_mem}', 'unit': 'KiB'}]}}
+            numa_path = {'element_attrs': ['./cpu/numa/cell/[@memory="${numa_mem}"]']}
+        - no_numa:
+    variants:
+        - memory_allocation:
+            mem_unit = "KiB"
+            current_mem_unit = "KiB"
+            current_mem = "2097152"
+            mem_value = "2097152"
+            mem_attrs = {'memory_unit':'${mem_unit}','memory':${mem_value},'current_mem':${current_mem},'current_mem_unit':'${current_mem_unit}'}

libvirt/tests/src/memory/memory_backing/discard_memory_content_setting.py

@@ -0,0 +1,161 @@
+# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+#
+#   Copyright Redhat
+#
+#   SPDX-License-Identifier: GPL-2.0
+
+#   Author: Nan Li<[email protected]>
+#
+# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+from virttest import test_setup
+
+from virttest.libvirt_xml import vm_xml
+from virttest.utils_test import libvirt
+from virttest.utils_libvirt import libvirt_vmxml
+
+
+def run(test, params, env):
+    """
+    1. Verify memory discard setting takes effect
+    2. Verify the numa topology discard setting takes effect
+    against memory backing setting
+    """
+
+    def get_init_vm_attrs():
+        """
+        Get vm attrs.
+
+        :return vm_attrs: expected vm attrs dict.
+        """
+        mb_value = ""
+        for item in [source_attr, hugepages_attr, mem_discard_attr]:
+            if item != "":
+                mb_value = mb_value + item + ","
+
+        vm_attrs = eval("{'mb':{%s}}" % mb_value[:-1])
+
+        if numa_attrs:
+            vm_attrs.update(numa_attrs)
+        vm_attrs.update(mem_attrs)
+        test.log.debug("Get current vm attrs is :%s" % vm_attrs)
+
+        return vm_attrs
+
+    def get_expected_xpath():
+        """
+        Get expected xpath.
+
+        :return expect_xpath: Get xpath according to the cfg file.
+        """
+        expect_xpath = []
+        for xpath in [numa_path, source_path, hugepages_path, mem_xpath,
+                      mem_discard_path]:
+            if xpath != "":
+                expect_xpath.append(eval(xpath))
+        test.log.debug("Get expected xpath: %s", expect_xpath)
+        return expect_xpath
+
+    def get_expected_discard():
+        """
+        Get expected discard value.
+
+        :return expected_discard : the expected discard value, True or False
+        :return existed: expected the expected_discard exist or not
+        """
+        expected_discard, existed = "true", True
+
+        if source in ["file", "hugepaged_file"]:
+            if mem_discard == "mem_discard_yes" and numa_discard in \
+                    ["numa_discard_yes", "numa_discard_not_defined", "no_numa"]:
+                expected_discard = "true"
+
+            elif mem_discard == "mem_discard_not_defined" and \
+                    numa_discard == "numa_discard_yes":
+                expected_discard = "true"
+
+            elif mem_discard in ["mem_discard_yes", "mem_discard_not_defined"] \
+                    and numa_discard == "numa_discard_no":
+                expected_discard = "false"
+            else:
+                existed = False
+
+        elif source in ["anonymous", "memfd"]:
+            existed = False
+
+        test.log.debug("Get expected discard:%s, discard existed: %s",
+                       expected_discard, existed)
+        return expected_discard, existed
+
+    def setup_test():
+        """
+        Prepare memory device
+        """
+        test.log.info("TEST_SETUP: Set hugepage.")
+        hp_cfg.set_kernel_hugepages(set_pagesize, set_pagenum)
+
+    def run_test():
+        """
+        """
+        test.log.info("TEST_STEP1: Define vm.")
+        vmxml = vm_xml.VMXML.new_from_dumpxml(vm_name)
+        vm_attrs = get_init_vm_attrs()
+        vmxml.setup_attrs(**vm_attrs)
+        vmxml.sync()
+        vmxml = vm_xml.VMXML.new_from_inactive_dumpxml(vm_name)
+        test.log.debug("After define vm, vm xml is:\n:%s", vmxml)
+
+        test.log.info("TEST_STEP2: Start vm.")
+        vm.start()
+        vm.wait_for_login().close()
+
+        test.log.info("TEST_STEP3: Check the xml config.")
+        vmxml = vm_xml.VMXML.new_from_dumpxml(vm_name)
+        expect_xpath = get_expected_xpath()
+        libvirt_vmxml.check_guest_xml_by_xpaths(vmxml, expect_xpath)
+
+        test.log.info("TEST_STEP4: Check the qemu cmd line.")
+        expected_discard, existed = get_expected_discard()
+        libvirt.check_qemu_cmd_line(qemu_line % expected_discard,
+                                    expect_exist=existed)
+
+    def teardown_test():
+        """
+        Clean data.
+        """
+        test.log.info("TEST_TEARDOWN: Clean up env.")
+        hp_cfg.cleanup()
+        bkxml.sync()
+
+    vm_name = params.get("main_vm")
+    vm = env.get_vm(vm_name)
+    vmxml = vm_xml.VMXML.new_from_inactive_dumpxml(vm_name)
+    bkxml = vmxml.copy()
+
+    qemu_line = params.get("qemu_line")
+    numa_discard = params.get("numa_discard")
+    mem_discard = params.get("mem_discard")
+    set_pagesize = params.get("set_pagesize")
+    set_pagenum = params.get("set_pagenum")
+
+    source_attr = params.get("source_attr", '')
+    hugepages_attr = params.get("hugepages_attr", '')
+    mem_discard_attr = params.get("mem_discard_attr", '')
+    numa_attrs = eval(params.get("numa_attrs", '{}'))
+    mem_attrs = eval(params.get("mem_attrs", '{}'))
+    mem_discard_attr = params.get("mem_discard_attr", '')
+
+    numa_path = params.get("numa_path", '')
+    source_path = params.get("source_path", '')
+    hugepages_path = params.get("hugepages_path", '')
+    mem_xpath = params.get("mem_xpath", '')
+    mem_discard_path = params.get("mem_discard_path", '')
+    source = params.get("source", '')
+    hp_cfg = test_setup.HugePageConfig(params)
+
+    try:
+        setup_test()
+        run_test()
+
+    finally:
+        teardown_test()