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From: Brendan Higgins <brendanhiggins@google.com>
To: shuah@kernel.org, davidgow@google.com
Cc: linux-kselftest@vger.kernel.org, kunit-dev@googlegroups.com,
	linux-kernel@vger.kernel.org, corbet@lwn.net,
	linux-doc@vger.kernel.org, sboyd@kernel.org,
	keescook@chromium.org, frowand.list@gmail.com,
	dlatypov@google.com, Brendan Higgins <brendanhiggins@google.com>
Subject: [RFC v2 3/4] kunit: tool: add support for QEMU
Date: Thu, 29 Apr 2021 13:51:08 -0700	[thread overview]
Message-ID: <20210429205109.2847831-4-brendanhiggins@google.com> (raw)
In-Reply-To: <20210429205109.2847831-1-brendanhiggins@google.com>

Add basic support to run QEMU via kunit_tool. Add support for i386,
x86_64, arm, arm64, and a bunch more.

Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
---
 tools/testing/kunit/kunit.py           |  33 +++-
 tools/testing/kunit/kunit_config.py    |   2 +-
 tools/testing/kunit/kunit_kernel.py    | 207 +++++++++++++++++++++----
 tools/testing/kunit/kunit_tool_test.py |  15 +-
 4 files changed, 217 insertions(+), 40 deletions(-)

diff --git a/tools/testing/kunit/kunit.py b/tools/testing/kunit/kunit.py
index d5144fcb03acd..07ef80062873b 100755
--- a/tools/testing/kunit/kunit.py
+++ b/tools/testing/kunit/kunit.py
@@ -70,10 +70,10 @@ def build_tests(linux: kunit_kernel.LinuxSourceTree,
 	kunit_parser.print_with_timestamp('Building KUnit Kernel ...')
 
 	build_start = time.time()
-	success = linux.build_um_kernel(request.alltests,
-					request.jobs,
-					request.build_dir,
-					request.make_options)
+	success = linux.build_kernel(request.alltests,
+				     request.jobs,
+				     request.build_dir,
+				     request.make_options)
 	build_end = time.time()
 	if not success:
 		return KunitResult(KunitStatus.BUILD_FAILURE,
@@ -187,6 +187,14 @@ def add_common_opts(parser) -> None:
 			     help='Path to Kconfig fragment that enables KUnit tests',
 			     metavar='kunitconfig')
 
+	parser.add_argument('--arch',
+			    help='Specifies the architecture to run tests under.',
+			    type=str, default='um', metavar='arch')
+
+	parser.add_argument('--cross_compile',
+			    help='Sets make\'s CROSS_COMPILE variable.',
+			    metavar='cross_compile')
+
 def add_build_opts(parser) -> None:
 	parser.add_argument('--jobs',
 			    help='As in the make command, "Specifies  the number of '
@@ -268,7 +276,10 @@ def main(argv, linux=None):
 			os.mkdir(cli_args.build_dir)
 
 		if not linux:
-			linux = kunit_kernel.LinuxSourceTree(cli_args.build_dir, kunitconfig_path=cli_args.kunitconfig)
+			linux = kunit_kernel.LinuxSourceTree(cli_args.build_dir,
+					kunitconfig_path=cli_args.kunitconfig,
+					arch=cli_args.arch,
+					cross_compile=cli_args.cross_compile)
 
 		request = KunitRequest(cli_args.raw_output,
 				       cli_args.timeout,
@@ -287,7 +298,9 @@ def main(argv, linux=None):
 			os.mkdir(cli_args.build_dir)
 
 		if not linux:
-			linux = kunit_kernel.LinuxSourceTree(cli_args.build_dir, kunitconfig_path=cli_args.kunitconfig)
+			linux = kunit_kernel.LinuxSourceTree(cli_args.build_dir,
+					kunitconfig_path=cli_args.kunitconfig,
+					arch=cli_args.arch)
 
 		request = KunitConfigRequest(cli_args.build_dir,
 					     cli_args.make_options)
@@ -299,7 +312,9 @@ def main(argv, linux=None):
 			sys.exit(1)
 	elif cli_args.subcommand == 'build':
 		if not linux:
-			linux = kunit_kernel.LinuxSourceTree(cli_args.build_dir, kunitconfig_path=cli_args.kunitconfig)
+			linux = kunit_kernel.LinuxSourceTree(cli_args.build_dir,
+					kunitconfig_path=cli_args.kunitconfig,
+					arch=cli_args.arch)
 
 		request = KunitBuildRequest(cli_args.jobs,
 					    cli_args.build_dir,
@@ -313,7 +328,9 @@ def main(argv, linux=None):
 			sys.exit(1)
 	elif cli_args.subcommand == 'exec':
 		if not linux:
-			linux = kunit_kernel.LinuxSourceTree(cli_args.build_dir)
+			linux = kunit_kernel.LinuxSourceTree(cli_args.build_dir,
+					kunitconfig_path=cli_args.kunitconfig,
+					arch=cli_args.arch)
 
 		exec_request = KunitExecRequest(cli_args.timeout,
 						cli_args.build_dir,
diff --git a/tools/testing/kunit/kunit_config.py b/tools/testing/kunit/kunit_config.py
index 1e2683dcc0e7a..07d76be392544 100644
--- a/tools/testing/kunit/kunit_config.py
+++ b/tools/testing/kunit/kunit_config.py
@@ -53,7 +53,7 @@ class Kconfig(object):
 		return True
 
 	def write_to_file(self, path: str) -> None:
-		with open(path, 'w') as f:
+		with open(path, 'a+') as f:
 			for entry in self.entries():
 				f.write(str(entry) + '\n')
 
diff --git a/tools/testing/kunit/kunit_kernel.py b/tools/testing/kunit/kunit_kernel.py
index 7d5b77967d48f..b8b3b76aaa17e 100644
--- a/tools/testing/kunit/kunit_kernel.py
+++ b/tools/testing/kunit/kunit_kernel.py
@@ -15,6 +15,8 @@ from typing import Iterator
 
 from contextlib import ExitStack
 
+from collections import namedtuple
+
 import kunit_config
 import kunit_parser
 
@@ -40,6 +42,10 @@ class BuildError(Exception):
 class LinuxSourceTreeOperations(object):
 	"""An abstraction over command line operations performed on a source tree."""
 
+	def __init__(self, linux_arch, cross_compile):
+		self._linux_arch = linux_arch
+		self._cross_compile = cross_compile
+
 	def make_mrproper(self) -> None:
 		try:
 			subprocess.check_output(['make', 'mrproper'], stderr=subprocess.STDOUT)
@@ -48,12 +54,18 @@ class LinuxSourceTreeOperations(object):
 		except subprocess.CalledProcessError as e:
 			raise ConfigError(e.output.decode())
 
+	def make_arch_qemuconfig(self, build_dir):
+		pass
+
 	def make_olddefconfig(self, build_dir, make_options) -> None:
-		command = ['make', 'ARCH=um', 'olddefconfig']
+		command = ['make', 'ARCH=' + self._linux_arch, 'olddefconfig']
+		if self._cross_compile:
+			command += ['CROSS_COMPILE=' + self._cross_compile]
 		if make_options:
 			command.extend(make_options)
 		if build_dir:
 			command += ['O=' + build_dir]
+		print(' '.join(command))
 		try:
 			subprocess.check_output(command, stderr=subprocess.STDOUT)
 		except OSError as e:
@@ -61,6 +73,154 @@ class LinuxSourceTreeOperations(object):
 		except subprocess.CalledProcessError as e:
 			raise ConfigError(e.output.decode())
 
+	def make(self, jobs, build_dir, make_options) -> None:
+		command = ['make', 'ARCH=' + self._linux_arch, '--jobs=' + str(jobs)]
+		if make_options:
+			command.extend(make_options)
+		if self._cross_compile:
+			command += ['CROSS_COMPILE=' + self._cross_compile]
+		if build_dir:
+			command += ['O=' + build_dir]
+		print(' '.join(command))
+		try:
+			proc = subprocess.Popen(command,
+						stderr=subprocess.PIPE,
+						stdout=subprocess.DEVNULL)
+		except OSError as e:
+			raise BuildError('Could not call execute make: ' + e)
+		except subprocess.CalledProcessError as e:
+			raise BuildError(e.output)
+		_, stderr = proc.communicate()
+		if proc.returncode != 0:
+			raise BuildError(stderr.decode())
+		if stderr:  # likely only due to build warnings
+			print(stderr.decode())
+
+	def run(self, params, timeout, build_dir, outfile) -> None:
+		pass
+
+
+QemuArchParams = namedtuple('QemuArchParams', ['linux_arch',
+					       'qemuconfig',
+					       'qemu_arch',
+					       'kernel_path',
+					       'kernel_command_line',
+					       'extra_qemu_params'])
+
+
+QEMU_ARCHS = {
+	'i386'		: QemuArchParams(linux_arch='i386',
+				qemuconfig='CONFIG_SERIAL_8250=y\nCONFIG_SERIAL_8250_CONSOLE=y',
+				qemu_arch='x86_64',
+				kernel_path='arch/x86/boot/bzImage',
+				kernel_command_line='console=ttyS0',
+				extra_qemu_params=['']),
+	'x86_64'	: QemuArchParams(linux_arch='x86_64',
+				qemuconfig='CONFIG_SERIAL_8250=y\nCONFIG_SERIAL_8250_CONSOLE=y',
+				qemu_arch='x86_64',
+				kernel_path='arch/x86/boot/bzImage',
+				kernel_command_line='console=ttyS0',
+				extra_qemu_params=['']),
+	'arm'		: QemuArchParams(linux_arch='arm',
+				qemuconfig='''CONFIG_ARCH_VIRT=y
+CONFIG_SERIAL_AMBA_PL010=y
+CONFIG_SERIAL_AMBA_PL010_CONSOLE=y
+CONFIG_SERIAL_AMBA_PL011=y
+CONFIG_SERIAL_AMBA_PL011_CONSOLE=y''',
+				qemu_arch='arm',
+				kernel_path='arch/arm/boot/zImage',
+				kernel_command_line='console=ttyAMA0',
+				extra_qemu_params=['-machine virt']),
+	'arm64'		: QemuArchParams(linux_arch='arm64',
+				qemuconfig='''CONFIG_SERIAL_AMBA_PL010=y
+CONFIG_SERIAL_AMBA_PL010_CONSOLE=y
+CONFIG_SERIAL_AMBA_PL011=y
+CONFIG_SERIAL_AMBA_PL011_CONSOLE=y''',
+				qemu_arch='aarch64',
+				kernel_path='arch/arm64/boot/Image.gz',
+				kernel_command_line='console=ttyAMA0',
+				extra_qemu_params=['-machine virt', '-cpu cortex-a57']),
+	'alpha'		: QemuArchParams(linux_arch='alpha',
+				qemuconfig='CONFIG_SERIAL_8250=y\nCONFIG_SERIAL_8250_CONSOLE=y',
+				qemu_arch='alpha',
+				kernel_path='arch/alpha/boot/vmlinux',
+				kernel_command_line='console=ttyS0',
+				extra_qemu_params=['']),
+	'powerpc'	: QemuArchParams(linux_arch='powerpc',
+				qemuconfig='CONFIG_PPC64=y\nCONFIG_SERIAL_8250=y\nCONFIG_SERIAL_8250_CONSOLE=y\nCONFIG_HVC_CONSOLE=y',
+				qemu_arch='ppc64',
+				kernel_path='vmlinux',
+				kernel_command_line='console=ttyS0',
+				extra_qemu_params=['-M pseries', '-cpu power8']),
+	'riscv'		: QemuArchParams(linux_arch='riscv',
+				qemuconfig='CONFIG_SOC_VIRT=y\nCONFIG_SERIAL_8250=y\nCONFIG_SERIAL_8250_CONSOLE=y\nCONFIG_SERIAL_OF_PLATFORM=y\nCONFIG_SERIAL_EARLYCON_RISCV_SBI=y',
+				qemu_arch='riscv64',
+				kernel_path='arch/riscv/boot/Image',
+				kernel_command_line='console=ttyS0',
+				extra_qemu_params=['-machine virt', '-cpu rv64', '-bios opensbi-riscv64-generic-fw_dynamic.bin']),
+	's390'		: QemuArchParams(linux_arch='s390',
+				qemuconfig='CONFIG_EXPERT=y\nCONFIG_TUNE_ZEC12=y\nCONFIG_NUMA=y\nCONFIG_MODULES=y',
+				qemu_arch='s390x',
+				kernel_path='arch/s390/boot/bzImage',
+				kernel_command_line='console=ttyS0',
+				extra_qemu_params=[
+						'-machine s390-ccw-virtio',
+						'-cpu qemu',]),
+	'sparc'		: QemuArchParams(linux_arch='sparc',
+				qemuconfig='CONFIG_SERIAL_8250=y\nCONFIG_SERIAL_8250_CONSOLE=y',
+				qemu_arch='sparc',
+				kernel_path='arch/sparc/boot/zImage',
+				kernel_command_line='console=ttyS0 mem=256M',
+				extra_qemu_params=['-m 256']),
+}
+
+class LinuxSourceTreeOperationsQemu(LinuxSourceTreeOperations):
+
+	def __init__(self, qemu_arch_params, cross_compile):
+		super().__init__(linux_arch=qemu_arch_params.linux_arch,
+				 cross_compile=cross_compile)
+		self._qemuconfig = qemu_arch_params.qemuconfig
+		self._qemu_arch = qemu_arch_params.qemu_arch
+		self._kernel_path = qemu_arch_params.kernel_path
+		print(self._kernel_path)
+		self._kernel_command_line = qemu_arch_params.kernel_command_line + ' kunit_shutdown=reboot'
+		self._extra_qemu_params = qemu_arch_params.extra_qemu_params
+
+	def make_arch_qemuconfig(self, build_dir):
+		qemuconfig = kunit_config.Kconfig()
+		qemuconfig.parse_from_string(self._qemuconfig)
+		qemuconfig.write_to_file(get_kconfig_path(build_dir))
+
+	def run(self, params, timeout, build_dir, outfile):
+		kernel_path = os.path.join(build_dir, self._kernel_path)
+		qemu_command = ['qemu-system-' + self._qemu_arch,
+				'-nodefaults',
+				'-m', '1024',
+				'-kernel', kernel_path,
+				'-append', '\'' + ' '.join(params + [self._kernel_command_line]) + '\'',
+				'-no-reboot',
+				'-nographic',
+				'-serial stdio'] + self._extra_qemu_params
+		print(' '.join(qemu_command))
+		with open(outfile, 'w') as output:
+			process = subprocess.Popen(' '.join(qemu_command),
+						   stdin=subprocess.PIPE,
+						   stdout=output,
+						   stderr=subprocess.STDOUT,
+						   text=True, shell=True)
+		try:
+			process.wait(timeout=timeout)
+		except Exception as e:
+			print(e)
+			process.terminate()
+		return process
+
+class LinuxSourceTreeOperationsUml(LinuxSourceTreeOperations):
+	"""An abstraction over command line operations performed on a source tree."""
+
+	def __init__(self):
+		super().__init__(linux_arch='um', cross_compile=None)
+
 	def make_allyesconfig(self, build_dir, make_options) -> None:
 		kunit_parser.print_with_timestamp(
 			'Enabling all CONFIGs for UML...')
@@ -83,32 +243,16 @@ class LinuxSourceTreeOperations(object):
 		kunit_parser.print_with_timestamp(
 			'Starting Kernel with all configs takes a few minutes...')
 
-	def make(self, jobs, build_dir, make_options) -> None:
-		command = ['make', 'ARCH=um', '--jobs=' + str(jobs)]
-		if make_options:
-			command.extend(make_options)
-		if build_dir:
-			command += ['O=' + build_dir]
-		try:
-			proc = subprocess.Popen(command,
-						stderr=subprocess.PIPE,
-						stdout=subprocess.DEVNULL)
-		except OSError as e:
-			raise BuildError('Could not call make command: ' + str(e))
-		_, stderr = proc.communicate()
-		if proc.returncode != 0:
-			raise BuildError(stderr.decode())
-		if stderr:  # likely only due to build warnings
-			print(stderr.decode())
-
-	def linux_bin(self, params, timeout, build_dir) -> None:
+	def run(self, params, timeout, build_dir, outfile):
 		"""Runs the Linux UML binary. Must be named 'linux'."""
 		linux_bin = get_file_path(build_dir, 'linux')
 		outfile = get_outfile_path(build_dir)
 		with open(outfile, 'w') as output:
 			process = subprocess.Popen([linux_bin] + params,
+						   stdin=subprocess.PIPE,
 						   stdout=output,
-						   stderr=subprocess.STDOUT)
+						   stderr=subprocess.STDOUT,
+						   text=True)
 			process.wait(timeout)
 
 def get_kconfig_path(build_dir) -> str:
@@ -123,10 +267,17 @@ def get_outfile_path(build_dir) -> str:
 class LinuxSourceTree(object):
 	"""Represents a Linux kernel source tree with KUnit tests."""
 
-	def __init__(self, build_dir: str, load_config=True, kunitconfig_path='') -> None:
+	def __init__(self, build_dir: str, load_config=True, kunitconfig_path='', arch=None, cross_compile=None) -> None:
 		signal.signal(signal.SIGINT, self.signal_handler)
-
-		self._ops = LinuxSourceTreeOperations()
+		self._ops = None
+		if arch is None or arch == 'um':
+			self._arch = 'um'
+			self._ops = LinuxSourceTreeOperationsUml()
+		elif arch in QEMU_ARCHS:
+			self._arch = arch
+			self._ops = LinuxSourceTreeOperationsQemu(QEMU_ARCHS[arch], cross_compile=cross_compile)
+		else:
+			raise ConfigError(arch + ' is not a valid arch')
 
 		if not load_config:
 			return
@@ -170,6 +321,7 @@ class LinuxSourceTree(object):
 			os.mkdir(build_dir)
 		self._kconfig.write_to_file(kconfig_path)
 		try:
+			self._ops.make_arch_qemuconfig(build_dir)
 			self._ops.make_olddefconfig(build_dir, make_options)
 		except ConfigError as e:
 			logging.error(e)
@@ -192,10 +344,13 @@ class LinuxSourceTree(object):
 			print('Generating .config ...')
 			return self.build_config(build_dir, make_options)
 
-	def build_um_kernel(self, alltests, jobs, build_dir, make_options) -> bool:
+	def build_kernel(self, alltests, jobs, build_dir, make_options) -> bool:
 		try:
 			if alltests:
+				if self._arch != 'um':
+					raise ConfigError('Only the "um" arch is supported for alltests')
 				self._ops.make_allyesconfig(build_dir, make_options)
+			self._ops.make_arch_qemuconfig(build_dir)
 			self._ops.make_olddefconfig(build_dir, make_options)
 			self._ops.make(jobs, build_dir, make_options)
 		except (ConfigError, BuildError) as e:
@@ -209,8 +364,8 @@ class LinuxSourceTree(object):
 		args.extend(['mem=1G', 'console=tty','kunit_shutdown=halt'])
 		if filter_glob:
 			args.append('kunit.filter_glob='+filter_glob)
-		self._ops.linux_bin(args, timeout, build_dir)
 		outfile = get_outfile_path(build_dir)
+		self._ops.run(args, timeout, build_dir, outfile)
 		subprocess.call(['stty', 'sane'])
 		with open(outfile, 'r') as file:
 			for line in file:
diff --git a/tools/testing/kunit/kunit_tool_test.py b/tools/testing/kunit/kunit_tool_test.py
index 1ad3049e90698..25e8be95a575d 100755
--- a/tools/testing/kunit/kunit_tool_test.py
+++ b/tools/testing/kunit/kunit_tool_test.py
@@ -297,7 +297,7 @@ class KUnitMainTest(unittest.TestCase):
 
 		self.linux_source_mock = mock.Mock()
 		self.linux_source_mock.build_reconfig = mock.Mock(return_value=True)
-		self.linux_source_mock.build_um_kernel = mock.Mock(return_value=True)
+		self.linux_source_mock.build_kernel = mock.Mock(return_value=True)
 		self.linux_source_mock.run_kernel = mock.Mock(return_value=all_passed_log)
 
 	def test_config_passes_args_pass(self):
@@ -308,7 +308,7 @@ class KUnitMainTest(unittest.TestCase):
 	def test_build_passes_args_pass(self):
 		kunit.main(['build'], self.linux_source_mock)
 		self.assertEqual(self.linux_source_mock.build_reconfig.call_count, 0)
-		self.linux_source_mock.build_um_kernel.assert_called_once_with(False, 8, '.kunit', None)
+		self.linux_source_mock.build_kernel.assert_called_once_with(False, 8, '.kunit', None)
 		self.assertEqual(self.linux_source_mock.run_kernel.call_count, 0)
 
 	def test_exec_passes_args_pass(self):
@@ -390,7 +390,7 @@ class KUnitMainTest(unittest.TestCase):
 	def test_build_builddir(self):
 		build_dir = '.kunit'
 		kunit.main(['build', '--build_dir', build_dir], self.linux_source_mock)
-		self.linux_source_mock.build_um_kernel.assert_called_once_with(False, 8, build_dir, None)
+		self.linux_source_mock.build_kernel.assert_called_once_with(False, 8, build_dir, None)
 
 	def test_exec_builddir(self):
 		build_dir = '.kunit'
@@ -404,14 +404,19 @@ class KUnitMainTest(unittest.TestCase):
 		mock_linux_init.return_value = self.linux_source_mock
 		kunit.main(['run', '--kunitconfig=mykunitconfig'])
 		# Just verify that we parsed and initialized it correctly here.
-		mock_linux_init.assert_called_once_with('.kunit', kunitconfig_path='mykunitconfig')
+		mock_linux_init.assert_called_once_with('.kunit',
+							kunitconfig_path='mykunitconfig',
+							arch='um',
+							cross_compile=None)
 
 	@mock.patch.object(kunit_kernel, 'LinuxSourceTree')
 	def test_config_kunitconfig(self, mock_linux_init):
 		mock_linux_init.return_value = self.linux_source_mock
 		kunit.main(['config', '--kunitconfig=mykunitconfig'])
 		# Just verify that we parsed and initialized it correctly here.
-		mock_linux_init.assert_called_once_with('.kunit', kunitconfig_path='mykunitconfig')
+		mock_linux_init.assert_called_once_with('.kunit',
+							kunitconfig_path='mykunitconfig',
+							arch='um')
 
 if __name__ == '__main__':
 	unittest.main()
-- 
2.31.1.498.g6c1eba8ee3d-goog


  parent reply	other threads:[~2021-04-29 20:51 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-29 20:51 [RFC v2 0/4] kunit: tool: add support for QEMU Brendan Higgins
2021-04-29 20:51 ` [RFC v2 1/4] kunit: Add 'kunit_shutdown' option Brendan Higgins
2021-04-29 21:52   ` Daniel Latypov
2021-04-29 20:51 ` [RFC v2 2/4] Documentation: Add kunit_shutdown to kernel-parameters.txt Brendan Higgins
2021-04-29 20:51 ` Brendan Higgins [this message]
2021-04-29 23:39   ` [RFC v2 3/4] kunit: tool: add support for QEMU Daniel Latypov
2021-04-30 20:01     ` Brendan Higgins
2021-04-30 20:14       ` Daniel Latypov
2021-05-03 21:19         ` Brendan Higgins
2021-05-04  6:08   ` David Gow
2021-05-04 20:07     ` Brendan Higgins
2021-04-29 20:51 ` [RFC v2 4/4] Documentation: kunit: document support for QEMU in kunit_tool Brendan Higgins

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