@@ -13,6 +13,7 @@
#include <linux/types.h>
#include <linux/slab.h>
#include <kunit/kunit-stream.h>
+#include <kunit/try-catch.h>
struct kunit_resource;
@@ -179,15 +180,26 @@ struct kunit {
/* private: internal use only. */
const char *name; /* Read only after initialization! */
+ struct kunit_try_catch try_catch;
bool success; /* Read only after test_case finishes! */
struct mutex lock; /* Gaurds all mutable test state. */
+ bool death_test; /* Protected by lock. */
struct list_head resources; /* Protected by lock. */
};
+static inline void kunit_set_death_test(struct kunit *test, bool death_test)
+{
+ mutex_lock(&test->lock);
+ test->death_test = death_test;
+ mutex_unlock(&test->lock);
+}
+
void kunit_init_test(struct kunit *test, const char *name);
void kunit_fail(struct kunit *test, struct kunit_stream *stream);
+void kunit_abort(struct kunit *test);
+
int kunit_run_tests(struct kunit_suite *suite);
/**
new file mode 100644
@@ -0,0 +1,69 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * An API to allow a function, that may fail, to be executed, and recover in a
+ * controlled manner.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+
+#ifndef _KUNIT_TRY_CATCH_H
+#define _KUNIT_TRY_CATCH_H
+
+#include <linux/types.h>
+
+typedef void (*kunit_try_catch_func_t)(void *);
+
+struct kunit;
+
+/*
+ * struct kunit_try_catch - provides a generic way to run code which might fail.
+ * @context: used to pass user data to the try and catch functions.
+ *
+ * kunit_try_catch provides a generic, architecture independent way to execute
+ * an arbitrary function of type kunit_try_catch_func_t which may bail out by
+ * calling kunit_try_catch_throw(). If kunit_try_catch_throw() is called, @try
+ * is stopped at the site of invocation and @catch is catch is called.
+ *
+ * struct kunit_try_catch provides a generic interface for the functionality
+ * needed to implement kunit->abort() which in turn is needed for implementing
+ * assertions. Assertions allow stating a precondition for a test simplifying
+ * how test cases are written and presented.
+ *
+ * Assertions are like expectations, except they abort (call
+ * kunit_try_catch_throw()) when the specified condition is not met. This is
+ * useful when you look at a test case as a logical statement about some piece
+ * of code, where assertions are the premises for the test case, and the
+ * conclusion is a set of predicates, rather expectations, that must all be
+ * true. If your premises are violated, it does not makes sense to continue.
+ */
+struct kunit_try_catch {
+ /* private: internal use only. */
+ struct kunit *test;
+ struct completion *try_completion;
+ int try_result;
+ kunit_try_catch_func_t try;
+ kunit_try_catch_func_t catch;
+ void *context;
+};
+
+void kunit_try_catch_init(struct kunit_try_catch *try_catch,
+ struct kunit *test,
+ kunit_try_catch_func_t try,
+ kunit_try_catch_func_t catch);
+
+void kunit_try_catch_run(struct kunit_try_catch *try_catch, void *context);
+
+void __noreturn kunit_try_catch_throw(struct kunit_try_catch *try_catch);
+
+static inline int kunit_try_catch_get_result(struct kunit_try_catch *try_catch)
+{
+ return try_catch->try_result;
+}
+
+/*
+ * Exposed for testing only.
+ */
+void kunit_generic_try_catch_init(struct kunit_try_catch *try_catch);
+
+#endif /* _KUNIT_TRY_CATCH_H */
@@ -1,6 +1,7 @@
obj-$(CONFIG_KUNIT) += test.o \
string-stream.o \
- kunit-stream.o
+ kunit-stream.o \
+ try-catch.o
obj-$(CONFIG_KUNIT_TEST) += string-stream-test.o
@@ -8,12 +8,24 @@
#include <linux/sched/debug.h>
#include <kunit/test.h>
+#include <kunit/try-catch.h>
static void kunit_set_failure(struct kunit *test)
{
WRITE_ONCE(test->success, false);
}
+static bool kunit_get_death_test(struct kunit *test)
+{
+ bool death_test;
+
+ mutex_lock(&test->lock);
+ death_test = test->death_test;
+ mutex_unlock(&test->lock);
+
+ return death_test;
+}
+
static int kunit_vprintk_emit(int level, const char *fmt, va_list args)
{
return vprintk_emit(0, level, NULL, 0, fmt, args);
@@ -126,40 +138,175 @@ void kunit_fail(struct kunit *test, struct kunit_stream *stream)
kunit_stream_commit(stream);
}
+void __noreturn kunit_abort(struct kunit *test)
+{
+ kunit_set_death_test(test, true);
+
+ kunit_try_catch_throw(&test->try_catch);
+
+ /*
+ * Throw could not abort from test.
+ *
+ * XXX: we should never reach this line! As kunit_try_catch_throw is
+ * marked __noreturn.
+ */
+ WARN_ONCE(true, "Throw could not abort from test!\n");
+}
+
void kunit_init_test(struct kunit *test, const char *name)
{
mutex_init(&test->lock);
INIT_LIST_HEAD(&test->resources);
test->name = name;
test->success = true;
+ test->death_test = false;
}
/*
- * Performs all logic to run a test case.
+ * Initializes and runs test case. Does not clean up or do post validations.
*/
-static void kunit_run_case(struct kunit_suite *suite,
- struct kunit_case *test_case)
+static void kunit_run_case_internal(struct kunit *test,
+ struct kunit_suite *suite,
+ struct kunit_case *test_case)
{
- struct kunit test;
- int ret = 0;
-
- kunit_init_test(&test, test_case->name);
+ int ret;
if (suite->init) {
- ret = suite->init(&test);
+ ret = suite->init(test);
if (ret) {
- kunit_err(&test, "failed to initialize: %d\n", ret);
- kunit_set_failure(&test);
+ kunit_err(test, "failed to initialize: %d\n", ret);
+ kunit_set_failure(test);
return;
}
}
- test_case->run_case(&test);
+ test_case->run_case(test);
+}
+
+static void kunit_case_internal_cleanup(struct kunit *test)
+{
+ kunit_cleanup(test);
+}
+/*
+ * Performs post validations and cleanup after a test case was run.
+ * XXX: Should ONLY BE CALLED AFTER kunit_run_case_internal!
+ */
+static void kunit_run_case_cleanup(struct kunit *test,
+ struct kunit_suite *suite)
+{
if (suite->exit)
- suite->exit(&test);
+ suite->exit(test);
+
+ kunit_case_internal_cleanup(test);
+}
+
+/*
+ * Handles an unexpected crash in a test case.
+ */
+static void kunit_handle_test_crash(struct kunit *test,
+ struct kunit_suite *suite,
+ struct kunit_case *test_case)
+{
+ kunit_err(test, "kunit test case crashed!");
+ /*
+ * TODO(brendanhiggins@google.com): This prints the stack trace up
+ * through this frame, not up to the frame that caused the crash.
+ */
+ show_stack(NULL, NULL);
+
+ kunit_case_internal_cleanup(test);
+}
+
+struct kunit_try_catch_context {
+ struct kunit *test;
+ struct kunit_suite *suite;
+ struct kunit_case *test_case;
+};
+
+static void kunit_try_run_case(void *data)
+{
+ struct kunit_try_catch_context *ctx = data;
+ struct kunit *test = ctx->test;
+ struct kunit_suite *suite = ctx->suite;
+ struct kunit_case *test_case = ctx->test_case;
+
+ /*
+ * kunit_run_case_internal may encounter a fatal error; if it does,
+ * abort will be called, this thread will exit, and finally the parent
+ * thread will resume control and handle any necessary clean up.
+ */
+ kunit_run_case_internal(test, suite, test_case);
+ /* This line may never be reached. */
+ kunit_run_case_cleanup(test, suite);
+}
+
+static void kunit_catch_run_case(void *data)
+{
+ struct kunit_try_catch_context *ctx = data;
+ struct kunit *test = ctx->test;
+ struct kunit_suite *suite = ctx->suite;
+ struct kunit_case *test_case = ctx->test_case;
+ int try_exit_code = kunit_try_catch_get_result(&test->try_catch);
+
+ if (try_exit_code) {
+ kunit_set_failure(test);
+ /*
+ * Test case could not finish, we have no idea what state it is
+ * in, so don't do clean up.
+ */
+ if (try_exit_code == -ETIMEDOUT)
+ kunit_err(test, "test case timed out\n");
+ /*
+ * Unknown internal error occurred preventing test case from
+ * running, so there is nothing to clean up.
+ */
+ else
+ kunit_err(test, "internal error occurred preventing test case from running: %d\n",
+ try_exit_code);
+ return;
+ }
+
+ if (kunit_get_death_test(test)) {
+ /*
+ * EXPECTED DEATH: kunit_run_case_internal encountered
+ * anticipated fatal error. Everything should be in a safe
+ * state.
+ */
+ kunit_run_case_cleanup(test, suite);
+ } else {
+ /*
+ * UNEXPECTED DEATH: kunit_run_case_internal encountered an
+ * unanticipated fatal error. We have no idea what the state of
+ * the test case is in.
+ */
+ kunit_handle_test_crash(test, suite, test_case);
+ kunit_set_failure(test);
+ }
+}
+
+/*
+ * Performs all logic to run a test case. It also catches most errors that
+ * occurs in a test case and reports them as failures.
+ */
+static void kunit_run_case_catch_errors(struct kunit_suite *suite,
+ struct kunit_case *test_case)
+{
+ struct kunit_try_catch_context context;
+ struct kunit_try_catch *try_catch;
+ struct kunit test;
+
+ kunit_init_test(&test, test_case->name);
+ try_catch = &test.try_catch;
- kunit_cleanup(&test);
+ kunit_try_catch_init(try_catch,
+ &test,
+ kunit_try_run_case,
+ kunit_catch_run_case);
+ context.test = &test;
+ context.suite = suite;
+ context.test_case = test_case;
+ kunit_try_catch_run(try_catch, &context);
test_case->success = test.success;
}
@@ -172,7 +319,7 @@ int kunit_run_tests(struct kunit_suite *suite)
kunit_print_subtest_start(suite);
for (test_case = suite->test_cases; test_case->run_case; test_case++) {
- kunit_run_case(suite, test_case);
+ kunit_run_case_catch_errors(suite, test_case);
kunit_print_test_case_ok_not_ok(test_case, test_case_count++);
}
new file mode 100644
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * An API to allow a function, that may fail, to be executed, and recover in a
+ * controlled manner.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+
+#include <kunit/try-catch.h>
+#include <kunit/test.h>
+#include <linux/completion.h>
+#include <linux/kthread.h>
+
+void __noreturn kunit_try_catch_throw(struct kunit_try_catch *try_catch)
+{
+ try_catch->try_result = -EFAULT;
+ complete_and_exit(try_catch->try_completion, -EFAULT);
+}
+
+static int kunit_generic_run_threadfn_adapter(void *data)
+{
+ struct kunit_try_catch *try_catch = data;
+
+ try_catch->try(try_catch->context);
+
+ complete_and_exit(try_catch->try_completion, 0);
+}
+
+void kunit_try_catch_run(struct kunit_try_catch *try_catch, void *context)
+{
+ DECLARE_COMPLETION_ONSTACK(try_completion);
+ struct kunit *test = try_catch->test;
+ struct task_struct *task_struct;
+ int exit_code, status;
+
+ try_catch->context = context;
+ try_catch->try_completion = &try_completion;
+ try_catch->try_result = 0;
+ task_struct = kthread_run(kunit_generic_run_threadfn_adapter,
+ try_catch,
+ "kunit_try_catch_thread");
+ if (IS_ERR(task_struct)) {
+ try_catch->catch(try_catch->context);
+ return;
+ }
+
+ /*
+ * TODO(brendanhiggins@google.com): We should probably have some type of
+ * variable timeout here. The only question is what that timeout value
+ * should be.
+ *
+ * The intention has always been, at some point, to be able to label
+ * tests with some type of size bucket (unit/small, integration/medium,
+ * large/system/end-to-end, etc), where each size bucket would get a
+ * default timeout value kind of like what Bazel does:
+ * https://docs.bazel.build/versions/master/be/common-definitions.html#test.size
+ * There is still some debate to be had on exactly how we do this. (For
+ * one, we probably want to have some sort of test runner level
+ * timeout.)
+ *
+ * For more background on this topic, see:
+ * https://mike-bland.com/2011/11/01/small-medium-large.html
+ */
+ status = wait_for_completion_timeout(&try_completion,
+ 300 * MSEC_PER_SEC); /* 5 min */
+ if (status < 0) {
+ kunit_err(test, "try timed out\n");
+ try_catch->try_result = -ETIMEDOUT;
+ }
+
+ exit_code = try_catch->try_result;
+
+ if (!exit_code)
+ return;
+
+ if (exit_code == -EFAULT)
+ try_catch->try_result = 0;
+ else if (exit_code == -EINTR)
+ kunit_err(test, "wake_up_process() was never called\n");
+ else if (exit_code)
+ kunit_err(test, "Unknown error: %d\n", exit_code);
+
+ try_catch->catch(try_catch->context);
+}
+
+void kunit_try_catch_init(struct kunit_try_catch *try_catch,
+ struct kunit *test,
+ kunit_try_catch_func_t try,
+ kunit_try_catch_func_t catch)
+{
+ try_catch->test = test;
+ try_catch->try = try;
+ try_catch->catch = catch;
+}