tests: rbtree to add and modify some tastcases

Add two testcases,one of them verify rbtree node can be embedded
in any user struct.
And another verify some operations in logarithmic time.

Signed-off-by: Ningx Zhao <ningx.zhao@intel.com>

tests/unit/rbtree/main.c

@@ -5,6 +5,7 @@
  */
 #include <ztest.h>
 #include <sys/rb.h>
+#include "time.h"
 
 #include "../../../lib/os/rb.c"
 
@@ -17,10 +18,15 @@ static struct rbtree tree;
 
 static struct rbnode nodes[MAX_NODES];
 
+struct container_node {
+	struct rbnode node;
+	int value;
+};
+
 /* Bit is set if node is in the tree */
 static unsigned int node_mask[(MAX_NODES + 31)/32];
 
-/* Array of nodes dumed via rb_walk */
+/* Array of nodes dumped via rb_walk */
 static struct rbnode *walked_nodes[MAX_NODES];
 
 /* Node currently being inserted, for testing lessthan() argument order */
@@ -245,9 +251,137 @@ void test_rbtree_spam(void)
 	} while (size < MAX_NODES);
 }
 
+/**
+ * @brief Test whether rbtree node struct is embedded
+ * in any user struct
+ *
+ * @details
+ * Initialize a user defined struct contains rbtree node
+ * Add into a rbtree
+ * Enumerate the rbtree node
+ *
+ * @ingroup lib_rbtree_tests
+ *
+ * @see RB_FOR_EACH(),RB_FOR_EACH_CONTAINER()
+ */
+void test_rbtree_container(void)
+{
+	int count = 0;
+	static struct rbtree test_tree_l;
+	struct container_node tree_node[10];
+	struct container_node *c_foreach_node;
+	struct rbnode *foreach_node;
+
+	memset(&test_tree_l, 0, sizeof(test_tree_l));
+	test_tree_l.lessthan_fn = node_lessthan;
+	memset(tree_node, 0, sizeof(tree_node));
+	for (unsigned int i = 0; i < 10; i++) {
+		tree_node[i].value = i;
+		rb_insert(&test_tree_l, &tree_node[i].node);
+	}
+
+	/*"for each" style iteration to verify node*/
+	RB_FOR_EACH(&test_tree_l, foreach_node) {
+		zassert_true(((struct container_node *)foreach_node)->value
+				== count, "RB_FOR_EACH failed");
+		count++;
+	}
+
+	count = 0;
+	/*"for each" style iteration to verify node*/
+	RB_FOR_EACH_CONTAINER(&test_tree_l, c_foreach_node, node) {
+		zassert_true(c_foreach_node->value == count,
+				"RB_FOR_EACH_CONTAINER failed");
+		count++;
+	}
+}
+
+
+
+static enum rbtree_perf_stats {
+	GET_MIN_MAX, INSERT_REMOVE, NO_OPERATION} operation;
+static clock_t time_spent[2][3];
+static int nodes_ii[2];
+clock_t check_rbtree_perf(struct rbtree *test_tree)
+{
+	struct rbnode node_test;
+	clock_t start = 0, finish = 0;
+
+	start = clock();
+	for (int i = 0; i < 10000; i++) {
+		switch (operation) {
+		case GET_MIN_MAX:
+			rb_get_min(test_tree);
+			rb_get_max(test_tree);
+			break;
+		case INSERT_REMOVE:
+			rb_insert(test_tree, &node_test);
+			rb_remove(test_tree, &node_test);
+			break;
+		default:
+			/*record the time of no operations running*/
+			break;
+		}
+	}
+	finish = clock();
+
+	return finish - start;
+}
+
+int repeat_operation(int nodes_, int index_)
+{
+	struct rbnode *node;
+	int nodes_real = 0;
+
+	test_tree(nodes_);
+	RB_FOR_EACH(&tree, node) {
+		nodes_real++;
+	}
+	operation = GET_MIN_MAX;
+	time_spent[index_][0] = check_rbtree_perf(&tree);
+	operation = INSERT_REMOVE;
+	time_spent[index_][1] = check_rbtree_perf(&tree);
+	operation = NO_OPERATION;
+	time_spent[index_][2] = check_rbtree_perf(&tree);
+
+	time_spent[index_][0] -= time_spent[index_][2];
+	time_spent[index_][1] -= time_spent[index_][2];
+
+	return nodes_real;
+}
+
+
+/**
+ * @brief Test rbtree some operations in logarithmic time
+ * complex
+ *
+ * @ingroup lib_rbtree_tests
+ *
+ * @see rb_get_min(),rb_get_max(),rb_insert(),rb_remove()
+ */
+void test_check_rbtree_perf(void)
+{
+	double log_N = 0, get_max_min = 0, insert_remove = 0;
+
+	nodes_ii[0] = repeat_operation(32, 0);
+	nodes_ii[1] = repeat_operation(256, 1);
+
+	/*log nodes_ii[1]/nodes_ii[0] = 2.736*/
+	log_N = 2.736;
+
+	get_max_min = (double)time_spent[1][0]/time_spent[0][0];
+	insert_remove = (double)time_spent[1][1]/time_spent[0][1];
+
+	zassert_within(get_max_min, log_N/2, 0.5, NULL);
+	zassert_within(insert_remove, log_N/2, 0.5, NULL);
+}
+
 void test_main(void)
 {
 	ztest_test_suite(test_rbtree,
-			 ztest_unit_test(test_rbtree_spam));
+			 ztest_unit_test(test_rbtree_spam),
+			 ztest_1cpu_unit_test(test_rbtree_container),
+			 ztest_unit_test(test_check_rbtree_perf)
+			 );
 	ztest_run_test_suite(test_rbtree);
 }