drm/xe/kunit: Add basic tests for GuC context ID Manager

Before we switch-over submission code to use new GuC context ID
Manager, lets add some kunit tests to make sure that ID manager
works as expected.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240313221112.1089-4-michal.wajdeczko@intel.com

drivers/gpu/drm/xe/tests/xe_guc_id_mgr_test.c

+// SPDX-License-Identifier: GPL-2.0 AND MIT
+/*
+ * Copyright © 2024 Intel Corporation
+ */
+
+#include <kunit/test.h>
+
+#include "xe_device.h"
+#include "xe_kunit_helpers.h"
+
+static int guc_id_mgr_test_init(struct kunit *test)
+{
+	struct xe_guc_id_mgr *idm;
+
+	xe_kunit_helper_xe_device_test_init(test);
+	idm = &xe_device_get_gt(test->priv, 0)->uc.guc.submission_state.idm;
+
+	mutex_init(idm_mutex(idm));
+	test->priv = idm;
+	return 0;
+}
+
+static void bad_init(struct kunit *test)
+{
+	struct xe_guc_id_mgr *idm = test->priv;
+
+	KUNIT_EXPECT_EQ(test, -EINVAL, xe_guc_id_mgr_init(idm, 0));
+	KUNIT_EXPECT_EQ(test, -ERANGE, xe_guc_id_mgr_init(idm, GUC_ID_MAX + 1));
+}
+
+static void no_init(struct kunit *test)
+{
+	struct xe_guc_id_mgr *idm = test->priv;
+
+	mutex_lock(idm_mutex(idm));
+	KUNIT_EXPECT_EQ(test, -ENODATA, xe_guc_id_mgr_reserve_locked(idm, 0));
+	mutex_unlock(idm_mutex(idm));
+
+	KUNIT_EXPECT_EQ(test, -ENODATA, xe_guc_id_mgr_reserve(idm, 1, 1));
+}
+
+static void init_fini(struct kunit *test)
+{
+	struct xe_guc_id_mgr *idm = test->priv;
+
+	KUNIT_ASSERT_EQ(test, 0, xe_guc_id_mgr_init(idm, -1));
+	KUNIT_EXPECT_NOT_NULL(test, idm->bitmap);
+	KUNIT_EXPECT_EQ(test, idm->total, GUC_ID_MAX);
+	__fini_idm(NULL, idm);
+	KUNIT_EXPECT_NULL(test, idm->bitmap);
+	KUNIT_EXPECT_EQ(test, idm->total, 0);
+}
+
+static void check_used(struct kunit *test)
+{
+	struct xe_guc_id_mgr *idm = test->priv;
+	unsigned int n;
+
+	KUNIT_ASSERT_EQ(test, 0, xe_guc_id_mgr_init(idm, 2));
+
+	mutex_lock(idm_mutex(idm));
+
+	for (n = 0; n < idm->total; n++) {
+		kunit_info(test, "n=%u", n);
+		KUNIT_EXPECT_EQ(test, idm->used, n);
+		KUNIT_EXPECT_GE(test, idm_reserve_chunk_locked(idm, 1, 0), 0);
+		KUNIT_EXPECT_EQ(test, idm->used, n + 1);
+	}
+	KUNIT_EXPECT_EQ(test, idm->used, idm->total);
+	idm_release_chunk_locked(idm, 0, idm->used);
+	KUNIT_EXPECT_EQ(test, idm->used, 0);
+
+	mutex_unlock(idm_mutex(idm));
+}
+
+static void check_quota(struct kunit *test)
+{
+	struct xe_guc_id_mgr *idm = test->priv;
+	unsigned int n;
+
+	KUNIT_ASSERT_EQ(test, 0, xe_guc_id_mgr_init(idm, 2));
+
+	mutex_lock(idm_mutex(idm));
+
+	for (n = 0; n < idm->total - 1; n++) {
+		kunit_info(test, "n=%u", n);
+		KUNIT_EXPECT_EQ(test, idm_reserve_chunk_locked(idm, 1, idm->total), -EDQUOT);
+		KUNIT_EXPECT_EQ(test, idm_reserve_chunk_locked(idm, 1, idm->total - n), -EDQUOT);
+		KUNIT_EXPECT_EQ(test, idm_reserve_chunk_locked(idm, idm->total - n, 1), -EDQUOT);
+		KUNIT_EXPECT_GE(test, idm_reserve_chunk_locked(idm, 1, 1), 0);
+	}
+	KUNIT_EXPECT_LE(test, 0, idm_reserve_chunk_locked(idm, 1, 0));
+	KUNIT_EXPECT_EQ(test, idm->used, idm->total);
+	idm_release_chunk_locked(idm, 0, idm->total);
+	KUNIT_EXPECT_EQ(test, idm->used, 0);
+
+	mutex_unlock(idm_mutex(idm));
+}
+
+static void check_all(struct kunit *test)
+{
+	struct xe_guc_id_mgr *idm = test->priv;
+	unsigned int n;
+
+	KUNIT_ASSERT_EQ(test, 0, xe_guc_id_mgr_init(idm, -1));
+
+	mutex_lock(idm_mutex(idm));
+
+	for (n = 0; n < idm->total; n++)
+		KUNIT_EXPECT_LE(test, 0, idm_reserve_chunk_locked(idm, 1, 0));
+	KUNIT_EXPECT_EQ(test, idm->used, idm->total);
+	for (n = 0; n < idm->total; n++)
+		idm_release_chunk_locked(idm, n, 1);
+
+	mutex_unlock(idm_mutex(idm));
+}
+
+static struct kunit_case guc_id_mgr_test_cases[] = {
+	KUNIT_CASE(bad_init),
+	KUNIT_CASE(no_init),
+	KUNIT_CASE(init_fini),
+	KUNIT_CASE(check_used),
+	KUNIT_CASE(check_quota),
+	KUNIT_CASE_SLOW(check_all),
+	{}
+};
+
+static struct kunit_suite guc_id_mgr_suite = {
+	.name = "guc_idm",
+	.test_cases = guc_id_mgr_test_cases,
+
+	.init = guc_id_mgr_test_init,
+	.exit = NULL,
+};
+
+kunit_test_suites(&guc_id_mgr_suite);

drivers/gpu/drm/xe/xe_guc_id_mgr.c

@@ -273,3 +273,7 @@ void xe_guc_id_mgr_print(struct xe_guc_id_mgr *idm, struct drm_printer *p, int i
 	idm_print_locked(idm, p, indent);
 	mutex_unlock(idm_mutex(idm));
 }
+
+#if IS_BUILTIN(CONFIG_DRM_XE_KUNIT_TEST)
+#include "tests/xe_guc_id_mgr_test.c"
+#endif