[RFC PATCH v2] dts: skip test cases based on capabilities

["Juraj Linkeš" <juraj.linkes@pantheon.tech>]

The devices under test may not support the capabilities required by
various test cases. Add support for:
1. Marking test suites and test cases with required capabilities,
2. Getting which required capabilities are supported by the device under
   test,
3. And then skipping test suites and test cases if their required
   capabilities are not supported by the device.

Signed-off-by: Juraj Linkeš <juraj.linkes@pantheon.tech>
---
 dts/framework/remote_session/__init__.py      |  2 +-
 dts/framework/remote_session/testpmd_shell.py | 44 ++++++++-
 dts/framework/runner.py                       | 46 ++++++++--
 dts/framework/test_result.py                  | 90 +++++++++++++++----
 dts/framework/test_suite.py                   | 25 ++++++
 dts/framework/testbed_model/sut_node.py       | 25 +++++-
 dts/tests/TestSuite_hello_world.py            |  4 +-
 7 files changed, 204 insertions(+), 32 deletions(-)

diff --git a/dts/framework/remote_session/__init__.py b/dts/framework/remote_session/__init__.py
index 1910c81c3c..f18a9f2259 100644
--- a/dts/framework/remote_session/__init__.py
+++ b/dts/framework/remote_session/__init__.py
@@ -22,7 +22,7 @@
 from .python_shell import PythonShell
 from .remote_session import CommandResult, RemoteSession
 from .ssh_session import SSHSession
-from .testpmd_shell import TestPmdShell
+from .testpmd_shell import NicCapability, TestPmdShell
 
 
 def create_remote_session(
diff --git a/dts/framework/remote_session/testpmd_shell.py b/dts/framework/remote_session/testpmd_shell.py
index cb2ab6bd00..f6783af621 100644
--- a/dts/framework/remote_session/testpmd_shell.py
+++ b/dts/framework/remote_session/testpmd_shell.py
@@ -16,7 +16,9 @@
 """
 
 import time
-from enum import auto
+from collections.abc import MutableSet
+from enum import Enum, auto
+from functools import partial
 from pathlib import PurePath
 from typing import Callable, ClassVar
 
@@ -229,3 +231,43 @@ def close(self) -> None:
         """Overrides :meth:`~.interactive_shell.close`."""
         self.send_command("quit", "")
         return super().close()
+
+    def get_capas_rxq(
+        self, supported_capabilities: MutableSet, unsupported_capabilities: MutableSet
+    ) -> None:
+        """Get all rxq capabilities and divide them into supported and unsupported.
+
+        Args:
+            supported_capabilities: A set where capabilities which are supported will be stored.
+            unsupported_capabilities: A set where capabilities which are
+                not supported will be stored.
+        """
+        self._logger.debug("Getting rxq capabilities.")
+        command = "show rxq info 0 0"
+        rxq_info = self.send_command(command)
+        for line in rxq_info.split("\n"):
+            bare_line = line.strip()
+            if bare_line.startswith("RX scattered packets:"):
+                if bare_line.endswith("on"):
+                    supported_capabilities.add(NicCapability.scattered_rx)
+                else:
+                    unsupported_capabilities.add(NicCapability.scattered_rx)
+
+
+class NicCapability(Enum):
+    """A mapping between capability names and the associated :class:`TestPmdShell` methods.
+
+    The :class:`TestPmdShell` method executes the command that checks
+    whether the capability is supported.
+
+    The signature of each :class:`TestPmdShell` method must be::
+
+        fn(self, supported_capabilities: MutableSet, unsupported_capabilities: MutableSet) -> None
+
+    The function must execute the testpmd command from which the capability support can be obtained.
+    If multiple capabilities can be obtained from the same testpmd command, each should be obtained
+    in one function. These capabilities should then be added to `supported_capabilities` or
+    `unsupported_capabilities` based on their support.
+    """
+
+    scattered_rx = partial(TestPmdShell.get_capas_rxq)
diff --git a/dts/framework/runner.py b/dts/framework/runner.py
index db8e3ba96b..7407ea30b8 100644
--- a/dts/framework/runner.py
+++ b/dts/framework/runner.py
@@ -501,6 +501,12 @@ def _run_test_suites(
         The method assumes the build target we're testing has already been built on the SUT node.
         The current build target thus corresponds to the current DPDK build present on the SUT node.
 
+        Before running any suites, the method determines whether they should be skipped
+        by inspecting any required capabilities the test suite needs and comparing those
+        to capabilities supported by the tested NIC. If all capabilities are supported,
+        the suite is run. If all test cases in a test suite would be skipped, the whole test suite
+        is skipped (the setup and teardown is not run).
+
         If a blocking test suite (such as the smoke test suite) fails, the rest of the test suites
         in the current build target won't be executed.
 
@@ -512,10 +518,30 @@ def _run_test_suites(
             test_suites_with_cases: The test suites with test cases to run.
         """
         end_build_target = False
+        required_capabilities = set()
+        supported_capabilities = set()
+        for test_suite_with_cases in test_suites_with_cases:
+            required_capabilities.update(test_suite_with_cases.req_capabilities)
+        self._logger.debug(f"Found required capabilities: {required_capabilities}")
+        if required_capabilities:
+            supported_capabilities = sut_node.get_supported_capabilities(required_capabilities)
         for test_suite_with_cases in test_suites_with_cases:
             test_suite_result = build_target_result.add_test_suite(test_suite_with_cases)
+            test_suite_with_cases.mark_skip(supported_capabilities)
             try:
-                self._run_test_suite(sut_node, tg_node, test_suite_result, test_suite_with_cases)
+                if test_suite_with_cases:
+                    self._run_test_suite(
+                        sut_node,
+                        tg_node,
+                        test_suite_result,
+                        test_suite_with_cases,
+                    )
+                else:
+                    self._logger.info(
+                        f"Test suite execution SKIPPED: "
+                        f"{test_suite_with_cases.test_suite_class.__name__}"
+                    )
+                    test_suite_result.update_setup(Result.SKIP)
             except BlockingTestSuiteError as e:
                 self._logger.exception(
                     f"An error occurred within {test_suite_with_cases.test_suite_class.__name__}. "
@@ -614,14 +640,18 @@ def _execute_test_suite(
             test_case_result = test_suite_result.add_test_case(test_case_name)
             all_attempts = SETTINGS.re_run + 1
             attempt_nr = 1
-            self._run_test_case(test_suite, test_case_method, test_case_result)
-            while not test_case_result and attempt_nr < all_attempts:
-                attempt_nr += 1
-                self._logger.info(
-                    f"Re-running FAILED test case '{test_case_name}'. "
-                    f"Attempt number {attempt_nr} out of {all_attempts}."
-                )
+            if TestSuiteWithCases.should_not_be_skipped(test_case_method):
                 self._run_test_case(test_suite, test_case_method, test_case_result)
+                while not test_case_result and attempt_nr < all_attempts:
+                    attempt_nr += 1
+                    self._logger.info(
+                        f"Re-running FAILED test case '{test_case_name}'. "
+                        f"Attempt number {attempt_nr} out of {all_attempts}."
+                    )
+                    self._run_test_case(test_suite, test_case_method, test_case_result)
+            else:
+                self._logger.info(f"Test case execution SKIPPED: {test_case_name}")
+                test_case_result.update_setup(Result.SKIP)
 
     def _run_test_case(
         self,
diff --git a/dts/framework/test_result.py b/dts/framework/test_result.py
index 28f84fd793..26c58a8606 100644
--- a/dts/framework/test_result.py
+++ b/dts/framework/test_result.py
@@ -24,12 +24,14 @@
 """
 
 import os.path
-from collections.abc import MutableSequence
-from dataclasses import dataclass
+from collections.abc import MutableSequence, MutableSet
+from dataclasses import dataclass, field
 from enum import Enum, auto
 from types import MethodType
 from typing import Union
 
+from framework.remote_session import NicCapability
+
 from .config import (
     OS,
     Architecture,
@@ -64,6 +66,14 @@ class is to hold a subset of test cases (which could be all test cases) because
 
     test_suite_class: type[TestSuite]
     test_cases: list[MethodType]
+    req_capabilities: set[NicCapability] = field(default_factory=set, init=False)
+
+    def __post_init__(self):
+        """Gather the required capabilities of the test suite and all test cases."""
+        for test_object in [self.test_suite_class] + self.test_cases:
+            test_object.skip = False
+            if hasattr(test_object, "req_capa"):
+                self.req_capabilities.update(test_object.req_capa)
 
     def create_config(self) -> TestSuiteConfig:
         """Generate a :class:`TestSuiteConfig` from the stored test suite with test cases.
@@ -76,6 +86,47 @@ def create_config(self) -> TestSuiteConfig:
             test_cases=[test_case.__name__ for test_case in self.test_cases],
         )
 
+    def mark_skip(self, supported_capabilities: MutableSet[NicCapability]) -> None:
+        """Mark the test suite and test cases to be skipped.
+
+        The mark is applied is object to be skipped requires any capabilities and at least one of
+        them is not among `capabilities`.
+
+        Args:
+            supported_capabilities: The supported capabilities.
+        """
+        for test_object in [self.test_suite_class] + self.test_cases:
+            if set(getattr(test_object, "req_capa", [])) - supported_capabilities:
+                test_object.skip = True
+
+    @staticmethod
+    def should_not_be_skipped(test_object: Union[type[TestSuite] | MethodType]) -> bool:
+        """Figure out whether `test_object` should be skipped.
+
+        If `test_object` is a :class:`TestSuite`, its test cases are not checked,
+        only the class itself.
+
+        Args:
+            test_object: The test suite or test case to be inspected.
+
+        Returns:
+            :data:`True` if the test suite or test case should be skipped, :data:`False` otherwise.
+        """
+        return not getattr(test_object, "skip", False)
+
+    def __bool__(self) -> bool:
+        """The truth value is determined by whether the test suite should be run.
+
+        Returns:
+            :data:`False` if the test suite should be skipped, :data:`True` otherwise.
+        """
+        found_test_case_to_run = False
+        for test_case in self.test_cases:
+            if self.should_not_be_skipped(test_case):
+                found_test_case_to_run = True
+                break
+        return found_test_case_to_run and self.should_not_be_skipped(self.test_suite_class)
+
 
 class Result(Enum):
     """The possible states that a setup, a teardown or a test case may end up in."""
@@ -170,12 +221,13 @@ def update_setup(self, result: Result, error: Exception | None = None) -> None:
         self.setup_result.result = result
         self.setup_result.error = error
 
-        if result in [Result.BLOCK, Result.ERROR, Result.FAIL]:
-            self.update_teardown(Result.BLOCK)
-            self._block_result()
+        if result != Result.PASS:
+            result_to_mark = Result.BLOCK if result != Result.SKIP else Result.SKIP
+            self.update_teardown(result_to_mark)
+            self._mark_results(result_to_mark)
 
-    def _block_result(self) -> None:
-        r"""Mark the result as :attr:`~Result.BLOCK`\ed.
+    def _mark_results(self, result) -> None:
+        """Mark the result as well as the child result as `result`.
 
         The blocking of child results should be done in overloaded methods.
         """
@@ -390,11 +442,11 @@ def add_sut_info(self, sut_info: NodeInfo) -> None:
         self.sut_os_version = sut_info.os_version
         self.sut_kernel_version = sut_info.kernel_version
 
-    def _block_result(self) -> None:
-        r"""Mark the result as :attr:`~Result.BLOCK`\ed."""
+    def _mark_results(self, result) -> None:
+        """Mark the result as well as the child result as `result`."""
         for build_target in self._config.build_targets:
             child_result = self.add_build_target(build_target)
-            child_result.update_setup(Result.BLOCK)
+            child_result.update_setup(result)
 
 
 class BuildTargetResult(BaseResult):
@@ -464,11 +516,11 @@ def add_build_target_info(self, versions: BuildTargetInfo) -> None:
         self.compiler_version = versions.compiler_version
         self.dpdk_version = versions.dpdk_version
 
-    def _block_result(self) -> None:
-        r"""Mark the result as :attr:`~Result.BLOCK`\ed."""
+    def _mark_results(self, result) -> None:
+        """Mark the result as well as the child result as `result`."""
         for test_suite_with_cases in self._test_suites_with_cases:
             child_result = self.add_test_suite(test_suite_with_cases)
-            child_result.update_setup(Result.BLOCK)
+            child_result.update_setup(result)
 
 
 class TestSuiteResult(BaseResult):
@@ -508,11 +560,11 @@ def add_test_case(self, test_case_name: str) -> "TestCaseResult":
         self.child_results.append(result)
         return result
 
-    def _block_result(self) -> None:
-        r"""Mark the result as :attr:`~Result.BLOCK`\ed."""
+    def _mark_results(self, result) -> None:
+        """Mark the result as well as the child result as `result`."""
         for test_case_method in self._test_suite_with_cases.test_cases:
             child_result = self.add_test_case(test_case_method.__name__)
-            child_result.update_setup(Result.BLOCK)
+            child_result.update_setup(result)
 
 
 class TestCaseResult(BaseResult, FixtureResult):
@@ -566,9 +618,9 @@ def add_stats(self, statistics: "Statistics") -> None:
         """
         statistics += self.result
 
-    def _block_result(self) -> None:
-        r"""Mark the result as :attr:`~Result.BLOCK`\ed."""
-        self.update(Result.BLOCK)
+    def _mark_results(self, result) -> None:
+        r"""Mark the result as `result`."""
+        self.update(result)
 
     def __bool__(self) -> bool:
         """The test case passed only if setup, teardown and the test case itself passed."""
diff --git a/dts/framework/test_suite.py b/dts/framework/test_suite.py
index 9c3b516002..07cdd294b9 100644
--- a/dts/framework/test_suite.py
+++ b/dts/framework/test_suite.py
@@ -13,6 +13,7 @@
     * Test case verification.
 """
 
+from collections.abc import Callable
 from ipaddress import IPv4Interface, IPv6Interface, ip_interface
 from typing import ClassVar, Union
 
@@ -20,6 +21,8 @@
 from scapy.layers.l2 import Ether  # type: ignore[import]
 from scapy.packet import Packet, Padding  # type: ignore[import]
 
+from framework.remote_session import NicCapability
+
 from .exception import TestCaseVerifyError
 from .logger import DTSLogger, get_dts_logger
 from .testbed_model import Port, PortLink, SutNode, TGNode
@@ -62,6 +65,7 @@ class TestSuite(object):
     #: Whether the test suite is blocking. A failure of a blocking test suite
     #: will block the execution of all subsequent test suites in the current build target.
     is_blocking: ClassVar[bool] = False
+    skip: bool
     _logger: DTSLogger
     _port_links: list[PortLink]
     _sut_port_ingress: Port
@@ -89,6 +93,7 @@ def __init__(
         """
         self.sut_node = sut_node
         self.tg_node = tg_node
+        self.skip = False
         self._logger = get_dts_logger(self.__class__.__name__)
         self._port_links = []
         self._process_links()
@@ -360,3 +365,23 @@ def _verify_l3_packet(self, received_packet: IP, expected_packet: IP) -> bool:
         if received_packet.src != expected_packet.src or received_packet.dst != expected_packet.dst:
             return False
         return True
+
+
+def requires(capability: NicCapability) -> Callable:
+    """A decorator that marks the decorated test case or test suite as one to be skipped.
+
+    Args:
+        The capability that's required by the decorated test case or test suite.
+
+    Returns:
+        The decorated function.
+    """
+
+    def add_req_capa(func) -> Callable:
+        if hasattr(func, "req_capa"):
+            func.req_capa.append(capability)
+        else:
+            func.req_capa = [capability]
+        return func
+
+    return add_req_capa
diff --git a/dts/framework/testbed_model/sut_node.py b/dts/framework/testbed_model/sut_node.py
index 97aa26d419..1fb536735d 100644
--- a/dts/framework/testbed_model/sut_node.py
+++ b/dts/framework/testbed_model/sut_node.py
@@ -15,7 +15,7 @@
 import tarfile
 import time
 from pathlib import PurePath
-from typing import Type
+from typing import Iterable, Type
 
 from framework.config import (
     BuildTargetConfiguration,
@@ -23,7 +23,7 @@
     NodeInfo,
     SutNodeConfiguration,
 )
-from framework.remote_session import CommandResult
+from framework.remote_session import CommandResult, NicCapability, TestPmdShell
 from framework.settings import SETTINGS
 from framework.utils import MesonArgs
 
@@ -228,6 +228,27 @@ def get_build_target_info(self) -> BuildTargetInfo:
     def _guess_dpdk_remote_dir(self) -> PurePath:
         return self.main_session.guess_dpdk_remote_dir(self._remote_tmp_dir)
 
+    def get_supported_capabilities(
+        self, capabilities: Iterable[NicCapability]
+    ) -> set[NicCapability]:
+        """Get the supported capabilities of the current NIC from `capabilities`.
+
+        Args:
+            capabilities: The capabilities to verify.
+
+        Returns:
+            The set of supported capabilities of the current NIC.
+        """
+        supported_capas: set[NicCapability] = set()
+        unsupported_capas: set[NicCapability] = set()
+        self._logger.debug(f"Checking which capabilities from {capabilities} NIC are supported.")
+        testpmd_shell = self.create_interactive_shell(TestPmdShell, privileged=True)
+        for capability in capabilities:
+            if capability not in supported_capas or capability not in unsupported_capas:
+                capability.value(testpmd_shell, supported_capas, unsupported_capas)
+        del testpmd_shell
+        return supported_capas
+
     def _set_up_build_target(self, build_target_config: BuildTargetConfiguration) -> None:
         """Setup DPDK on the SUT node.
 
diff --git a/dts/tests/TestSuite_hello_world.py b/dts/tests/TestSuite_hello_world.py
index fd7ff1534d..31b1564582 100644
--- a/dts/tests/TestSuite_hello_world.py
+++ b/dts/tests/TestSuite_hello_world.py
@@ -7,7 +7,8 @@
 No other EAL parameters apart from cores are used.
 """
 
-from framework.test_suite import TestSuite
+from framework.remote_session import NicCapability
+from framework.test_suite import TestSuite, requires
 from framework.testbed_model import (
     LogicalCoreCount,
     LogicalCoreCountFilter,
@@ -26,6 +27,7 @@ def set_up_suite(self) -> None:
         """
         self.app_helloworld_path = self.sut_node.build_dpdk_app("helloworld")
 
+    @requires(NicCapability.scattered_rx)
     def test_hello_world_single_core(self) -> None:
         """Single core test case.
 
-- 
2.34.1