[PATCH 2/7] drm/xe/tests: Add helpers for use in live tests

[Michal Wajdeczko]

Instead of iterating over available Xe devices within a testcase,
without being able to distinguish potential failures from different
devices on system with many Xe devices, introduce helpers that will
allow to treat each Xe device as a parameter for the testcase like:

static void bar(struct kunit *test)
{
	struct xe_device *xe = test->priv;
	...
}

struct kunit_case foo_live_tests[] = {
	KUNIT_CASE_PARAM(bar, xe_pci_live_device_gen_param),
	{}
};

struct kunit_suite foo_suite = {
	.name = "foo_live",
	.test_cases = foo_live_tests,
	.init = xe_kunit_helper_xe_device_live_test_init,
	.exit = xe_kunit_helper_xe_device_live_test_exit,
};

Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
---
 drivers/gpu/drm/xe/tests/xe_kunit_helpers.c | 55 +++++++++++++++++++++
 drivers/gpu/drm/xe/tests/xe_kunit_helpers.h |  3 ++
 drivers/gpu/drm/xe/tests/xe_pci.c           | 30 +++++++++++
 drivers/gpu/drm/xe/tests/xe_pci_test.h      |  2 +
 4 files changed, 90 insertions(+)

diff --git a/drivers/gpu/drm/xe/tests/xe_kunit_helpers.c b/drivers/gpu/drm/xe/tests/xe_kunit_helpers.c
index fefe79b3b75a..d68d887a2646 100644
--- a/drivers/gpu/drm/xe/tests/xe_kunit_helpers.c
+++ b/drivers/gpu/drm/xe/tests/xe_kunit_helpers.c
@@ -12,7 +12,9 @@
 
 #include "tests/xe_kunit_helpers.h"
 #include "tests/xe_pci_test.h"
+#include "xe_device.h"
 #include "xe_device_types.h"
+#include "xe_pm.h"
 
 /**
  * xe_kunit_helper_alloc_xe_device - Allocate a &xe_device for a KUnit test.
@@ -88,3 +90,56 @@ int xe_kunit_helper_xe_device_test_init(struct kunit *test)
 	return 0;
 }
 EXPORT_SYMBOL_IF_KUNIT(xe_kunit_helper_xe_device_test_init);
+
+/**
+ * xe_kunit_helper_xe_device_live_test_init - Prepare a &xe_device for
+ *                                            use in a live KUnit test.
+ * @test: the &kunit where live &xe_device will be used
+ *
+ * This function expects pointer to the &xe_device in the &test.param_value,
+ * like it is prepared by the &xe_pci_live_device_gen_param and stores that
+ * pointer as &kunit.priv to allow the test code to access it.
+ *
+ * This function makes sure that device is not wedged and then resumes it
+ * to avoid waking up the device inside the test.
+ *
+ * This function can be used as custom implementation of &kunit_suite.init
+ * but must be accompanied by the &xe_kunit_helper_xe_device_live_test_exit().
+ *
+ * This function uses KUNIT_ASSERT to detect any failures.
+ *
+ * Return: Always 0.
+ */
+int xe_kunit_helper_xe_device_live_test_init(struct kunit *test)
+{
+	struct xe_device *xe;
+
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test->param_value);
+	xe = xe_device_const_cast(test->param_value);
+
+	kunit_info(test, "running on %s device\n", xe->info.platform_name);
+
+	KUNIT_ASSERT_FALSE(test, xe_device_wedged(xe));
+	xe_pm_runtime_get(xe);
+
+	test->priv = xe;
+	return 0;
+}
+EXPORT_SYMBOL_IF_KUNIT(xe_kunit_helper_xe_device_live_test_init);
+
+/**
+ * xe_kunit_helper_xe_device_live_test_exit - Cleanup a live KUnit test.
+ * @test: the &kunit where live &xe_device was used
+ *
+ * This function accompanies the &xe_kunit_helper_xe_device_live_test_init()
+ * and should be used as custom implementation of &kunit_suite.exit.
+ */
+void xe_kunit_helper_xe_device_live_test_exit(struct kunit *test)
+{
+	struct xe_device *xe = test->priv;
+
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, xe);
+	xe_pm_runtime_put(xe);
+	KUNIT_EXPECT_FALSE(test, xe_device_wedged(xe));
+}
+EXPORT_SYMBOL_IF_KUNIT(xe_kunit_helper_xe_device_live_test_exit);
diff --git a/drivers/gpu/drm/xe/tests/xe_kunit_helpers.h b/drivers/gpu/drm/xe/tests/xe_kunit_helpers.h
index 067a1babf049..cc59ba23ade0 100644
--- a/drivers/gpu/drm/xe/tests/xe_kunit_helpers.h
+++ b/drivers/gpu/drm/xe/tests/xe_kunit_helpers.h
@@ -14,4 +14,7 @@ struct xe_device *xe_kunit_helper_alloc_xe_device(struct kunit *test,
 						  struct device *dev);
 int xe_kunit_helper_xe_device_test_init(struct kunit *test);
 
+int xe_kunit_helper_xe_device_live_test_init(struct kunit *test);
+void xe_kunit_helper_xe_device_live_test_exit(struct kunit *test);
+
 #endif
diff --git a/drivers/gpu/drm/xe/tests/xe_pci.c b/drivers/gpu/drm/xe/tests/xe_pci.c
index f62809ca8b51..ab570dbb71ac 100644
--- a/drivers/gpu/drm/xe/tests/xe_pci.c
+++ b/drivers/gpu/drm/xe/tests/xe_pci.c
@@ -167,3 +167,33 @@ int xe_pci_fake_device_init(struct xe_device *xe)
 	return 0;
 }
 EXPORT_SYMBOL_IF_KUNIT(xe_pci_fake_device_init);
+
+/**
+ * xe_pci_live_device_gen_param - Helper to iterate Xe devices as a KUnit parameters
+ * @prev: the previously returned value, or NULL for the first iteration
+ * @desc: the buffer for a parameter name
+ *
+ * Iterates over the available Xe devices on the system. Uses the device name
+ * as the parameter name.
+ *
+ * To be used only as a parameter generator function in &KUNIT_CASE_PARAM.
+ *
+ * Return: pointer to the next &struct xe_device ready to be used as a parameter
+ *         or NULL if there are no more Xe devices on the system.
+ */
+const void *xe_pci_live_device_gen_param(const void *prev, char *desc)
+{
+	const struct xe_device *xe = prev;
+	struct device *dev = xe ? xe->drm.dev : NULL;
+	struct device *next;
+
+	next = driver_find_next_device(&xe_pci_driver.driver, dev);
+	if (dev)
+		put_device(dev);
+	if (!next)
+		return NULL;
+
+	snprintf(desc, KUNIT_PARAM_DESC_SIZE, "%s", dev_name(next));
+	return pdev_to_xe_device(to_pci_dev(next));
+}
+EXPORT_SYMBOL_IF_KUNIT(xe_pci_live_device_gen_param);
diff --git a/drivers/gpu/drm/xe/tests/xe_pci_test.h b/drivers/gpu/drm/xe/tests/xe_pci_test.h
index f40dcec83992..3e2558bc3c90 100644
--- a/drivers/gpu/drm/xe/tests/xe_pci_test.h
+++ b/drivers/gpu/drm/xe/tests/xe_pci_test.h
@@ -35,4 +35,6 @@ struct xe_pci_fake_data {
 
 int xe_pci_fake_device_init(struct xe_device *xe);
 
+const void *xe_pci_live_device_gen_param(const void *prev, char *desc);
+
 #endif
-- 
2.43.0