| 1 | #!/usr/bin/env python3 |
| 2 | # |
| 3 | # Functional test that check overcommit memlock options |
| 4 | # |
| 5 | # Copyright (c) Yandex Technologies LLC, 2025 |
| 6 | # |
| 7 | # Author: |
| 8 | # Alexandr Moshkov <dtalexundeer@yandex-team.ru> |
| 9 | # |
| 10 | # SPDX-License-Identifier: GPL-2.0-or-later |
| 11 | |
| 12 | import re |
| 13 | |
| 14 | from typing import Dict |
| 15 | |
| 16 | from qemu_test import QemuSystemTest |
| 17 | from qemu_test import skipLockedMemoryTest, skipUnlessOperatingSystem |
| 18 | |
| 19 | |
| 20 | STATUS_VALUE_PATTERN = re.compile(r'^(\w+):\s+(\d+) kB', re.MULTILINE) |
| 21 | |
| 22 | |
| 23 | @skipUnlessOperatingSystem('Linux') |
| 24 | @skipLockedMemoryTest(2_097_152) # 2GB |
| 25 | class MemlockTest(QemuSystemTest): |
| 26 | """ |
| 27 | Runs a guest with memlock options. |
| 28 | Then verify, that this options is working correctly |
| 29 | by checking the status file of the QEMU process. |
| 30 | """ |
| 31 | |
| 32 | def common_vm_setup_with_memlock(self, memlock): |
| 33 | self.vm.add_args('-overcommit', f'mem-lock={memlock}') |
| 34 | self.vm.launch() |
| 35 | |
| 36 | def test_memlock_off(self): |
| 37 | self.common_vm_setup_with_memlock('off') |
| 38 | |
| 39 | status = self.get_process_status_values(self.vm.get_pid()) |
| 40 | |
| 41 | # libgcrypt may mlock a few pages |
| 42 | self.assertTrue(status['VmLck'] < 32) |
| 43 | |
| 44 | def test_memlock_on(self): |
| 45 | self.common_vm_setup_with_memlock('on') |
| 46 | |
| 47 | status = self.get_process_status_values(self.vm.get_pid()) |
| 48 | |
| 49 | # VmLck > 0 kB and almost all memory is resident |
| 50 | self.assertTrue(status['VmLck'] > 0) |
| 51 | self.assertTrue(status['VmRSS'] >= status['VmSize'] * 0.70) |
| 52 | |
| 53 | def test_memlock_onfault(self): |
| 54 | self.common_vm_setup_with_memlock('on-fault') |
| 55 | |
| 56 | status = self.get_process_status_values(self.vm.get_pid()) |
| 57 | |
| 58 | # VmLck > 0 kB and only few memory is resident |
| 59 | self.assertTrue(status['VmLck'] > 0) |
| 60 | self.assertTrue(status['VmRSS'] <= status['VmSize'] * 0.30) |
| 61 | |
| 62 | def get_process_status_values(self, pid: int) -> Dict[str, int]: |
| 63 | result = {} |
| 64 | raw_status = self._get_raw_process_status(pid) |
| 65 | |
| 66 | for line in raw_status.split('\n'): |
| 67 | if m := STATUS_VALUE_PATTERN.match(line): |
| 68 | result[m.group(1)] = int(m.group(2)) |
| 69 | |
| 70 | return result |
| 71 | |
| 72 | def _get_raw_process_status(self, pid: int) -> str: |
| 73 | status = None |
| 74 | try: |
| 75 | with open(f'/proc/{pid}/status', 'r', encoding="ascii") as f: |
| 76 | status = f.read() |
| 77 | except FileNotFoundError: |
| 78 | self.skipTest("Can't open status file of the process") |
| 79 | return status |
| 80 | |
| 81 | |
| 82 | if __name__ == '__main__': |
| 83 | MemlockTest.main() |