Merge tag 'linux-kselftest-kunit-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull kunit updates from Shuah Khan:

 - add support for running Rust documentation tests as KUnit tests

 - make init, str, sync, types doctests compilable/testable

 - add support for attributes API which include speed, modules
   attributes, ability to filter and report attributes

 - add support for marking tests slow using attributes API

 - add attributes API documentation

 - fix a wild-memory-access bug in kunit_filter_suites() and a possible
   memory leak in kunit_filter_suites()

 - add support for counting number of test suites in a module, list
   action to kunit test modules, and test filtering on module tests

* tag 'linux-kselftest-kunit-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (25 commits)
  kunit: fix struct kunit_attr header
  kunit: replace KUNIT_TRIGGER_STATIC_STUB maro with KUNIT_STATIC_STUB_REDIRECT
  kunit: Allow kunit test modules to use test filtering
  kunit: Make 'list' action available to kunit test modules
  kunit: Report the count of test suites in a module
  kunit: fix uninitialized variables bug in attributes filtering
  kunit: fix possible memory leak in kunit_filter_suites()
  kunit: fix wild-memory-access bug in kunit_filter_suites()
  kunit: Add documentation of KUnit test attributes
  kunit: add tests for filtering attributes
  kunit: time: Mark test as slow using test attributes
  kunit: memcpy: Mark tests as slow using test attributes
  kunit: tool: Add command line interface to filter and report attributes
  kunit: Add ability to filter attributes
  kunit: Add module attribute
  kunit: Add speed attribute
  kunit: Add test attributes API structure
  MAINTAINERS: add Rust KUnit files to the KUnit entry
  rust: support running Rust documentation tests as KUnit ones
  rust: types: make doctests compilable/testable
  ...

Author: torvalds

Documentation/dev-tools/kunit/run_wrapper.rst

@@ -321,3 +321,15 @@ command line arguments:
 
 - ``--json``: If set, stores the test results in a JSON format and prints to `stdout` or
   saves to a file if a filename is specified.
+
+- ``--filter``: Specifies filters on test attributes, for example, ``speed!=slow``.
+  Multiple filters can be used by wrapping input in quotes and separating filters
+  by commas. Example: ``--filter "speed>slow, module=example"``.
+
+- ``--filter_action``: If set to ``skip``, filtered tests will be shown as skipped
+  in the output rather than showing no output.
+
+- ``--list_tests``: If set, lists all tests that will be run.
+
+- ``--list_tests_attr``: If set, lists all tests that will be run and all of their
+  attributes.

Documentation/dev-tools/kunit/running_tips.rst

@@ -262,3 +262,169 @@ other code executed during boot, e.g.
 	# Reset coverage counters before running the test.
 	$ echo 0 > /sys/kernel/debug/gcov/reset
 	$ modprobe kunit-example-test
+
+
+Test Attributes and Filtering
+=============================
+
+Test suites and cases can be marked with test attributes, such as speed of
+test. These attributes will later be printed in test output and can be used to
+filter test execution.
+
+Marking Test Attributes
+-----------------------
+
+Tests are marked with an attribute by including a ``kunit_attributes`` object
+in the test definition.
+
+Test cases can be marked using the ``KUNIT_CASE_ATTR(test_name, attributes)``
+macro to define the test case instead of ``KUNIT_CASE(test_name)``.
+
+.. code-block:: c
+
+	static const struct kunit_attributes example_attr = {
+		.speed = KUNIT_VERY_SLOW,
+	};
+
+	static struct kunit_case example_test_cases[] = {
+		KUNIT_CASE_ATTR(example_test, example_attr),
+	};
+
+.. note::
+	To mark a test case as slow, you can also use ``KUNIT_CASE_SLOW(test_name)``.
+	This is a helpful macro as the slow attribute is the most commonly used.
+
+Test suites can be marked with an attribute by setting the "attr" field in the
+suite definition.
+
+.. code-block:: c
+
+	static const struct kunit_attributes example_attr = {
+		.speed = KUNIT_VERY_SLOW,
+	};
+
+	static struct kunit_suite example_test_suite = {
+		...,
+		.attr = example_attr,
+	};
+
+.. note::
+	Not all attributes need to be set in a ``kunit_attributes`` object. Unset
+	attributes will remain uninitialized and act as though the attribute is set
+	to 0 or NULL. Thus, if an attribute is set to 0, it is treated as unset.
+	These unset attributes will not be reported and may act as a default value
+	for filtering purposes.
+
+Reporting Attributes
+--------------------
+
+When a user runs tests, attributes will be present in the raw kernel output (in
+KTAP format). Note that attributes will be hidden by default in kunit.py output
+for all passing tests but the raw kernel output can be accessed using the
+``--raw_output`` flag. This is an example of how test attributes for test cases
+will be formatted in kernel output:
+
+.. code-block:: none
+
+	# example_test.speed: slow
+	ok 1 example_test
+
+This is an example of how test attributes for test suites will be formatted in
+kernel output:
+
+.. code-block:: none
+
+	  KTAP version 2
+	  # Subtest: example_suite
+	  # module: kunit_example_test
+	  1..3
+	  ...
+	ok 1 example_suite
+
+Additionally, users can output a full attribute report of tests with their
+attributes, using the command line flag ``--list_tests_attr``:
+
+.. code-block:: bash
+
+	kunit.py run "example" --list_tests_attr
+
+.. note::
+	This report can be accessed when running KUnit manually by passing in the
+	module_param ``kunit.action=list_attr``.
+
+Filtering
+---------
+
+Users can filter tests using the ``--filter`` command line flag when running
+tests. As an example:
+
+.. code-block:: bash
+
+	kunit.py run --filter speed=slow
+
+
+You can also use the following operations on filters: "<", ">", "<=", ">=",
+"!=", and "=". Example:
+
+.. code-block:: bash
+
+	kunit.py run --filter "speed>slow"
+
+This example will run all tests with speeds faster than slow. Note that the
+characters < and > are often interpreted by the shell, so they may need to be
+quoted or escaped, as above.
+
+Additionally, you can use multiple filters at once. Simply separate filters
+using commas. Example:
+
+.. code-block:: bash
+
+	kunit.py run --filter "speed>slow, module=kunit_example_test"
+
+.. note::
+	You can use this filtering feature when running KUnit manually by passing
+	the filter as a module param: ``kunit.filter="speed>slow, speed<=normal"``.
+
+Filtered tests will not run or show up in the test output. You can use the
+``--filter_action=skip`` flag to skip filtered tests instead. These tests will be
+shown in the test output in the test but will not run. To use this feature when
+running KUnit manually, use the module param ``kunit.filter_action=skip``.
+
+Rules of Filtering Procedure
+----------------------------
+
+Since both suites and test cases can have attributes, there may be conflicts
+between attributes during filtering. The process of filtering follows these
+rules:
+
+- Filtering always operates at a per-test level.
+
+- If a test has an attribute set, then the test's value is filtered on.
+
+- Otherwise, the value falls back to the suite's value.
+
+- If neither are set, the attribute has a global "default" value, which is used.
+
+List of Current Attributes
+--------------------------
+
+``speed``
+
+This attribute indicates the speed of a test's execution (how slow or fast the
+test is).
+
+This attribute is saved as an enum with the following categories: "normal",
+"slow", or "very_slow". The assumed default speed for tests is "normal". This
+indicates that the test takes a relatively trivial amount of time (less than
+1 second), regardless of the machine it is running on. Any test slower than
+this could be marked as "slow" or "very_slow".
+
+The macro ``KUNIT_CASE_SLOW(test_name)`` can be easily used to set the speed
+of a test case to "slow".
+
+``module``
+
+This attribute indicates the name of the module associated with the test.
+
+This attribute is automatically saved as a string and is printed for each suite.
+Tests can also be filtered using this attribute.

MAINTAINERS

@@ -11394,6 +11394,8 @@ T:	git git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest.git k
 F:	Documentation/dev-tools/kunit/
 F:	include/kunit/
 F:	lib/kunit/
+F:	rust/kernel/kunit.rs
+F:	scripts/rustdoc_test_*
 F:	tools/testing/kunit/
 
 KERNEL USERMODE HELPER

include/kunit/attributes.h

@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * KUnit API to save and access test attributes
+ *
+ * Copyright (C) 2023, Google LLC.
+ * Author: Rae Moar <rmoar@google.com>
+ */
+
+#ifndef _KUNIT_ATTRIBUTES_H
+#define _KUNIT_ATTRIBUTES_H
+
+/*
+ * struct kunit_attr_filter - representation of attributes filter with the
+ * attribute object and string input
+ */
+struct kunit_attr_filter {
+	struct kunit_attr *attr;
+	char *input;
+};
+
+/*
+ * Returns the name of the filter's attribute.
+ */
+const char *kunit_attr_filter_name(struct kunit_attr_filter filter);
+
+/*
+ * Print all test attributes for a test case or suite.
+ * Output format for test cases: "# <test_name>.<attribute>: <value>"
+ * Output format for test suites: "# <attribute>: <value>"
+ */
+void kunit_print_attr(void *test_or_suite, bool is_test, unsigned int test_level);
+
+/*
+ * Returns the number of fitlers in input.
+ */
+int kunit_get_filter_count(char *input);
+
+/*
+ * Parse attributes filter input and return an objects containing the
+ * attribute object and the string input of the next filter.
+ */
+struct kunit_attr_filter kunit_next_attr_filter(char **filters, int *err);
+
+/*
+ * Returns a copy of the suite containing only tests that pass the filter.
+ */
+struct kunit_suite *kunit_filter_attr_tests(const struct kunit_suite *const suite,
+		struct kunit_attr_filter filter, char *action, int *err);
+
+#endif /* _KUNIT_ATTRIBUTES_H */

include/kunit/static_stub.h

@@ -11,7 +11,7 @@
 #if !IS_ENABLED(CONFIG_KUNIT)
 
 /* If CONFIG_KUNIT is not enabled, these stubs quietly disappear. */
-#define KUNIT_TRIGGER_STATIC_STUB(real_fn_name, args...) do {} while (0)
+#define KUNIT_STATIC_STUB_REDIRECT(real_fn_name, args...) do {} while (0)
 
 #else
 
@@ -30,7 +30,7 @@
  * This is a function prologue which is used to allow calls to the current
  * function to be redirected by a KUnit test. KUnit tests can call
  * kunit_activate_static_stub() to pass a replacement function in. The
- * replacement function will be called by KUNIT_TRIGGER_STATIC_STUB(), which
+ * replacement function will be called by KUNIT_STATIC_STUB_REDIRECT(), which
  * will then return from the function. If the caller is not in a KUnit context,
  * the function will continue execution as normal.
  *
@@ -87,7 +87,7 @@ void __kunit_activate_static_stub(struct kunit *test,
  * When activated, calls to real_fn_addr from within this test (even if called
  * indirectly) will instead call replacement_addr. The function pointed to by
  * real_fn_addr must begin with the static stub prologue in
- * KUNIT_TRIGGER_STATIC_STUB() for this to work. real_fn_addr and
+ * KUNIT_STATIC_STUB_REDIRECT() for this to work. real_fn_addr and
  * replacement_addr must have the same type.
  *
  * The redirection can be disabled again with kunit_deactivate_static_stub().

include/kunit/test-bug.h

@@ -9,6 +9,8 @@
 #ifndef _KUNIT_TEST_BUG_H
 #define _KUNIT_TEST_BUG_H
 
+#include <linux/stddef.h> /* for NULL */
+
 #if IS_ENABLED(CONFIG_KUNIT)
 
 #include <linux/jump_label.h> /* For static branch */