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26#include <linux/plist.h>
27#include <linux/spinlock.h>
28
29#ifdef CONFIG_DEBUG_PI_LIST
30
31static struct plist_head test_head;
32
33static void plist_check_prev_next(struct list_head *t, struct list_head *p,
34 struct list_head *n)
35{
36 WARN(n->prev != p || p->next != n,
37 "top: %p, n: %p, p: %p\n"
38 "prev: %p, n: %p, p: %p\n"
39 "next: %p, n: %p, p: %p\n",
40 t, t->next, t->prev,
41 p, p->next, p->prev,
42 n, n->next, n->prev);
43}
44
45static void plist_check_list(struct list_head *top)
46{
47 struct list_head *prev = top, *next = top->next;
48
49 plist_check_prev_next(top, prev, next);
50 while (next != top) {
51 prev = next;
52 next = prev->next;
53 plist_check_prev_next(top, prev, next);
54 }
55}
56
57static void plist_check_head(struct plist_head *head)
58{
59 WARN_ON(head != &test_head && !head->rawlock && !head->spinlock);
60 if (head->rawlock)
61 WARN_ON_SMP(!raw_spin_is_locked(head->rawlock));
62 if (head->spinlock)
63 WARN_ON_SMP(!spin_is_locked(head->spinlock));
64 if (!plist_head_empty(head))
65 plist_check_list(&plist_first(head)->prio_list);
66 plist_check_list(&head->node_list);
67}
68
69#else
70# define plist_check_head(h) do { } while (0)
71#endif
72
73
74
75
76
77
78
79void plist_add(struct plist_node *node, struct plist_head *head)
80{
81 struct plist_node *first, *iter, *prev = NULL;
82 struct list_head *node_next = &head->node_list;
83
84 plist_check_head(head);
85 WARN_ON(!plist_node_empty(node));
86 WARN_ON(!list_empty(&node->prio_list));
87
88 if (plist_head_empty(head))
89 goto ins_node;
90
91 first = iter = plist_first(head);
92
93 do {
94 if (node->prio < iter->prio) {
95 node_next = &iter->node_list;
96 break;
97 }
98
99 prev = iter;
100 iter = list_entry(iter->prio_list.next,
101 struct plist_node, prio_list);
102 } while (iter != first);
103
104 if (!prev || prev->prio != node->prio)
105 list_add_tail(&node->prio_list, &iter->prio_list);
106ins_node:
107 list_add_tail(&node->node_list, node_next);
108
109 plist_check_head(head);
110}
111
112
113
114
115
116
117
118void plist_del(struct plist_node *node, struct plist_head *head)
119{
120 plist_check_head(head);
121
122 if (!list_empty(&node->prio_list)) {
123 if (node->node_list.next != &head->node_list) {
124 struct plist_node *next;
125
126 next = list_entry(node->node_list.next,
127 struct plist_node, node_list);
128
129
130 if (list_empty(&next->prio_list))
131 list_add(&next->prio_list, &node->prio_list);
132 }
133 list_del_init(&node->prio_list);
134 }
135
136 list_del_init(&node->node_list);
137
138 plist_check_head(head);
139}
140
141#ifdef CONFIG_DEBUG_PI_LIST
142#include <linux/sched.h>
143#include <linux/module.h>
144#include <linux/init.h>
145
146static struct plist_node __initdata test_node[241];
147
148static void __init plist_test_check(int nr_expect)
149{
150 struct plist_node *first, *prio_pos, *node_pos;
151
152 if (plist_head_empty(&test_head)) {
153 BUG_ON(nr_expect != 0);
154 return;
155 }
156
157 prio_pos = first = plist_first(&test_head);
158 plist_for_each(node_pos, &test_head) {
159 if (nr_expect-- < 0)
160 break;
161 if (node_pos == first)
162 continue;
163 if (node_pos->prio == prio_pos->prio) {
164 BUG_ON(!list_empty(&node_pos->prio_list));
165 continue;
166 }
167
168 BUG_ON(prio_pos->prio > node_pos->prio);
169 BUG_ON(prio_pos->prio_list.next != &node_pos->prio_list);
170 prio_pos = node_pos;
171 }
172
173 BUG_ON(nr_expect != 0);
174 BUG_ON(prio_pos->prio_list.next != &first->prio_list);
175}
176
177static int __init plist_test(void)
178{
179 int nr_expect = 0, i, loop;
180 unsigned int r = local_clock();
181
182 printk(KERN_INFO "start plist test\n");
183 plist_head_init(&test_head, NULL);
184 for (i = 0; i < ARRAY_SIZE(test_node); i++)
185 plist_node_init(test_node + i, 0);
186
187 for (loop = 0; loop < 1000; loop++) {
188 r = r * 193939 % 47629;
189 i = r % ARRAY_SIZE(test_node);
190 if (plist_node_empty(test_node + i)) {
191 r = r * 193939 % 47629;
192 test_node[i].prio = r % 99;
193 plist_add(test_node + i, &test_head);
194 nr_expect++;
195 } else {
196 plist_del(test_node + i, &test_head);
197 nr_expect--;
198 }
199 plist_test_check(nr_expect);
200 }
201
202 for (i = 0; i < ARRAY_SIZE(test_node); i++) {
203 if (plist_node_empty(test_node + i))
204 continue;
205 plist_del(test_node + i, &test_head);
206 nr_expect--;
207 plist_test_check(nr_expect);
208 }
209
210 printk(KERN_INFO "end plist test\n");
211 return 0;
212}
213
214module_init(plist_test);
215
216#endif
217
