gpu: nvgpu: add tests for kref

Add unit tests for kref unit.

Jira NVGPU-4417

Change-Id: Ie5c6efc72b95aa1f200a59fd9184f20e65548fee
Signed-off-by: ajesh <akv@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvgpu/+/2287553
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>

userspace/units/interface/kref/kref.h

@@ -0,0 +1,180 @@
+/*
+ * Copyright (c) 2020, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef UNIT_INTERFACE_KREF_H
+#define UNIT_INTERFACE_KREF_H
+
+struct gk20a;
+struct unit_module;
+
+/** @addtogroup SWUTS-interface-kref
+ *  @{
+ *
+ * Software Unit Test Specification for interface-kref
+ */
+
+/**
+ * Test specification for test_kref_init
+ *
+ * Description: Test the reference count initialization implementation.
+ *
+ * Test Type: Feature
+ *
+ * Targets: nvgpu_ref_init
+ *
+ * Input: None
+ *
+ * Steps:
+ * - Invoke the function nvgpu_ref_init to initialize nvgpu_ref structure.
+ * - Read back the refcount value and confirm the value is initialized to 1.
+ *   Otherwise, return FAIL.
+ * - Return PASS.
+ *
+ * Output: Returns PASS if the refcount is initialized correctly, otherwise
+ * returns FAIL.
+ */
+int test_kref_init(struct unit_module *m, struct gk20a *g, void *__args);
+
+/**
+ * Test specification for test_kref_get
+ *
+ * Description: Test the reference get implementation.
+ *
+ * Test Type: Feature
+ *
+ * Targets: nvgpu_ref_get
+ *
+ * Input: None
+ *
+ * Steps:
+ * - Invoke the function nvgpu_ref_init to initialize nvgpu_ref structure.
+ * - Invoke the function nvgpu_ref_get in loop to increment the refcount value
+ *   till LOOP_COUNT.
+ * - Read back the refcount value and confirm that the value returned is in
+ *   sync with the number of times nvgpu_ref_get is called. Otherwise return
+ *   FAIL.
+ * - Return PASS.
+ *
+ * Output: Returns PASS if the refcount is incremented correctly, otherwise
+ * returns FAIL.
+ */
+int test_kref_get(struct unit_module *m, struct gk20a *g, void *__args);
+
+/**
+ * Test specification for test_kref_get_unless
+ *
+ * Description: Test the reference get unless implementation.
+ *
+ * Test Type: Feature
+ *
+ * Targets: nvgpu_ref_get_unless_zero
+ *
+ * Input: None
+ *
+ * Steps:
+ * - Initialize the refcount value as 0 for nvgpu_ref struct.
+ * - Invoke function nvgpu_ref_get_unless_zero and confirm that the return
+ *   value is 0. Otherwise return FAIL.
+ * - Invoke the function nvgpu_ref_init to initialize nvgpu_ref structure.
+ * - Invoke the function nvgpu_ref_get_unless_zero to increment the refcount
+ *   value.
+ * - Check and confirm that the return value is not zero. Otherwise, return
+ *   FAIL.
+ * - Return PASS.
+ *
+ * Output: Returns SUCCESS if the refcount is increased correctly according to
+ * the current value in refcount, otherwise return FAIL.
+ */
+int test_kref_get_unless(struct unit_module *m, struct gk20a *g, void *__args);
+
+/**
+ * Test specification for test_kref_put
+ *
+ * Description: Test the reference put implementation.
+ *
+ * Test Type: Feature
+ *
+ * Targets: nvgpu_ref_put
+ *
+ * Input: None
+ *
+ * Steps:
+ * - Initialize the release_count as 0.
+ * - Invoke the function nvgpu_ref_init to initialize nvgpu_ref structure.
+ * - Invoke the function nvgpu_ref_get in loop to increment the refcount value
+ *   till LOOP_COUNT.
+ * - Read back the refcount value and confirm that the value returned is in
+ *   sync with the number of times nvgpu_ref_get is called. Otherwise return
+ *   FAIL.
+ * - Invoke the function nvgpu_ref_put in loop for LOOP_COUNT times to
+ *   decrement the refcount value to 0.
+ * - Check the value of release_count value which is incremented in the
+ *   release callback function to confirm that the release callback function
+ *   is invoked and invoked only once. Otherwise return FAIL.
+ * - Invoke the function nvgpu_ref_get to increment the refcount value.
+ * - Invoke the function  nvgpu_ref_put with callback as NULL.
+ * - Read back the refcount value and confirm that the value is reset to 0.
+ *   Otherwise return FAIL.
+ * - Return PASS.
+ *
+ * Output: Returns SUCCESS if the refcerence is released correctly, otherwise
+ * return FAIL.
+ */
+int test_kref_put(struct unit_module *m, struct gk20a *g, void *__args);
+
+/**
+ * Test specification for test_kref_put_return
+ *
+ * Description: Test the reference put return implementation.
+ *
+ * Test Type: Feature
+ *
+ * Targets: nvgpu_ref_put_return
+ *
+ * Input: None
+ *
+ * Steps:
+ * - Initialize the release_count as 0.
+ * - Invoke the function nvgpu_ref_init to initialize nvgpu_ref structure.
+ * - Invoke the function nvgpu_ref_get in loop to increment the refcount value.
+ * - Read back the refcount value and confirm that the value returned is in
+ *   sync with the number of times nvgpu_ref_get is called. Otherwise return
+ *   FAIL.
+ * - Invoke the function nvgpu_ref_put in loop for (LOOP_COUNT - 1) to
+ *   decrement the refcount value and confirm that the return value is always
+ *   zero. Otherwise return FAIL.
+ * - Invoke the function nvgpu_ref_put once more and confirm that the return
+ *   value is equal to one. Otherwise return FAIL.
+ * - Check the value of release_count value which is incremented in the
+ *   release callback function to confirm that the release callback function
+ *   is invoked and invoked only once. Otherwise return FAIL.
+ * - Invoke the function nvgpu_ref_get to increment the refcount value.
+ * - Invoke the function nvgpu_ref_put_return with callback as NULL.
+ * - Check the return value and return FAIL if it is equal to zero.
+ * - Return PASS.
+ *
+ * Output: Returns SUCCESS if the refcount is initialized correctly, otherwise
+ * return FAIL.
+ */
+int test_kref_put_return(struct unit_module *m, struct gk20a *g, void *__args);
+
+#endif /* UNIT_INTERFACE_KREF_H */