projects/linux·blob uaccess-cleanups · refs

369 lines · 8.6 KiB

1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/module.h>
3#include <linux/moduleparam.h>
4#include <linux/interval_tree.h>
5#include <linux/prandom.h>
6#include <linux/slab.h>
7#include <linux/printk.h>
8#include <asm/timex.h>
9#include <linux/bitmap.h>
10#include <linux/maple_tree.h>
11
12#define __param(type, name, init, msg) \
13 static type name = init; \
14 module_param(name, type, 0444); \
15 MODULE_PARM_DESC(name, msg);
16
17__param(int, nnodes, 100, "Number of nodes in the interval tree");
18__param(int, perf_loops, 1000, "Number of iterations modifying the tree");
19
20__param(int, nsearches, 100, "Number of searches to the interval tree");
21__param(int, search_loops, 1000, "Number of iterations searching the tree");
22__param(bool, search_all, false, "Searches will iterate all nodes in the tree");
23
24__param(uint, max_endpoint, ~0, "Largest value for the interval's endpoint");
25__param(ullong, seed, 3141592653589793238ULL, "Random seed");
26
27static struct rb_root_cached root = RB_ROOT_CACHED;
28static struct interval_tree_node *nodes = NULL;
29static u32 *queries = NULL;
30
31static struct rnd_state rnd;
32
33static inline unsigned long
34search(struct rb_root_cached *root, unsigned long start, unsigned long last)
35{
36 struct interval_tree_node *node;
37 unsigned long results = 0;
38
39 for (node = interval_tree_iter_first(root, start, last); node;
40 node = interval_tree_iter_next(node, start, last))
41 results++;
42 return results;
43}
44
45static void init(void)
46{
47 int i;
48
49 for (i = 0; i < nnodes; i++) {
50 u32 b = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
51 u32 a = (prandom_u32_state(&rnd) >> 4) % b;
52
53 nodes[i].start = a;
54 nodes[i].last = b;
55 }
56
57 /*
58 * Limit the search scope to what the user defined.
59 * Otherwise we are merely measuring empty walks,
60 * which is pointless.
61 */
62 for (i = 0; i < nsearches; i++)
63 queries[i] = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
64}
65
66static int basic_check(void)
67{
68 int i, j;
69 cycles_t time1, time2, time;
70
71 printk(KERN_ALERT "interval tree insert/remove");
72
73 init();
74
75 time1 = get_cycles();
76
77 for (i = 0; i < perf_loops; i++) {
78 for (j = 0; j < nnodes; j++)
79 interval_tree_insert(nodes + j, &root);
80 for (j = 0; j < nnodes; j++)
81 interval_tree_remove(nodes + j, &root);
82 }
83
84 time2 = get_cycles();
85 time = time2 - time1;
86
87 time = div_u64(time, perf_loops);
88 printk(" -> %llu cycles\n", (unsigned long long)time);
89
90 return 0;
91}
92
93static int search_check(void)
94{
95 int i, j;
96 unsigned long results;
97 cycles_t time1, time2, time;
98
99 printk(KERN_ALERT "interval tree search");
100
101 init();
102
103 for (j = 0; j < nnodes; j++)
104 interval_tree_insert(nodes + j, &root);
105
106 time1 = get_cycles();
107
108 results = 0;
109 for (i = 0; i < search_loops; i++)
110 for (j = 0; j < nsearches; j++) {
111 unsigned long start = search_all ? 0 : queries[j];
112 unsigned long last = search_all ? max_endpoint : queries[j];
113
114 results += search(&root, start, last);
115 }
116
117 time2 = get_cycles();
118 time = time2 - time1;
119
120 time = div_u64(time, search_loops);
121 results = div_u64(results, search_loops);
122 printk(" -> %llu cycles (%lu results)\n",
123 (unsigned long long)time, results);
124
125 for (j = 0; j < nnodes; j++)
126 interval_tree_remove(nodes + j, &root);
127
128 return 0;
129}
130
131static int intersection_range_check(void)
132{
133 int i, j, k;
134 unsigned long start, last;
135 struct interval_tree_node *node;
136 unsigned long *intxn1;
137 unsigned long *intxn2;
138
139 printk(KERN_ALERT "interval tree iteration\n");
140
141 intxn1 = bitmap_alloc(nnodes, GFP_KERNEL);
142 if (!intxn1) {
143 WARN_ONCE(1, "Failed to allocate intxn1\n");
144 return -ENOMEM;
145 }
146
147 intxn2 = bitmap_alloc(nnodes, GFP_KERNEL);
148 if (!intxn2) {
149 WARN_ONCE(1, "Failed to allocate intxn2\n");
150 bitmap_free(intxn1);
151 return -ENOMEM;
152 }
153
154 for (i = 0; i < search_loops; i++) {
155 /* Initialize interval tree for each round */
156 init();
157 for (j = 0; j < nnodes; j++)
158 interval_tree_insert(nodes + j, &root);
159
160 /* Let's try nsearches different ranges */
161 for (k = 0; k < nsearches; k++) {
162 /* Try whole range once */
163 if (!k) {
164 start = 0UL;
165 last = ULONG_MAX;
166 } else {
167 last = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
168 start = (prandom_u32_state(&rnd) >> 4) % last;
169 }
170
171 /* Walk nodes to mark intersection nodes */
172 bitmap_zero(intxn1, nnodes);
173 for (j = 0; j < nnodes; j++) {
174 node = nodes + j;
175
176 if (start <= node->last && last >= node->start)
177 bitmap_set(intxn1, j, 1);
178 }
179
180 /* Iterate tree to clear intersection nodes */
181 bitmap_zero(intxn2, nnodes);
182 for (node = interval_tree_iter_first(&root, start, last); node;
183 node = interval_tree_iter_next(node, start, last))
184 bitmap_set(intxn2, node - nodes, 1);
185
186 WARN_ON_ONCE(!bitmap_equal(intxn1, intxn2, nnodes));
187 }
188
189 for (j = 0; j < nnodes; j++)
190 interval_tree_remove(nodes + j, &root);
191 }
192
193 bitmap_free(intxn1);
194 bitmap_free(intxn2);
195 return 0;
196}
197
198#ifdef CONFIG_INTERVAL_TREE_SPAN_ITER
199/*
200 * Helper function to get span of current position from maple tree point of
201 * view.
202 */
203static void mas_cur_span(struct ma_state *mas, struct interval_tree_span_iter *state)
204{
205 unsigned long cur_start;
206 unsigned long cur_last;
207 int is_hole;
208
209 if (mas->status == ma_overflow)
210 return;
211
212 /* walk to current position */
213 state->is_hole = mas_walk(mas) ? 0 : 1;
214
215 cur_start = mas->index < state->first_index ?
216 state->first_index : mas->index;
217
218 /* whether we have followers */
219 do {
220
221 cur_last = mas->last > state->last_index ?
222 state->last_index : mas->last;
223
224 is_hole = mas_next_range(mas, state->last_index) ? 0 : 1;
225
226 } while (mas->status != ma_overflow && is_hole == state->is_hole);
227
228 if (state->is_hole) {
229 state->start_hole = cur_start;
230 state->last_hole = cur_last;
231 } else {
232 state->start_used = cur_start;
233 state->last_used = cur_last;
234 }
235
236 /* advance position for next round */
237 if (mas->status != ma_overflow)
238 mas_set(mas, cur_last + 1);
239}
240
241static int span_iteration_check(void)
242{
243 int i, j, k;
244 unsigned long start, last;
245 struct interval_tree_span_iter span, mas_span;
246
247 DEFINE_MTREE(tree);
248
249 MA_STATE(mas, &tree, 0, 0);
250
251 printk(KERN_ALERT "interval tree span iteration\n");
252
253 for (i = 0; i < search_loops; i++) {
254 /* Initialize interval tree for each round */
255 init();
256 for (j = 0; j < nnodes; j++)
257 interval_tree_insert(nodes + j, &root);
258
259 /* Put all the range into maple tree */
260 mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
261 mt_set_in_rcu(&tree);
262
263 for (j = 0; j < nnodes; j++)
264 WARN_ON_ONCE(mtree_store_range(&tree, nodes[j].start,
265 nodes[j].last, nodes + j, GFP_KERNEL));
266
267 /* Let's try nsearches different ranges */
268 for (k = 0; k < nsearches; k++) {
269 /* Try whole range once */
270 if (!k) {
271 start = 0UL;
272 last = ULONG_MAX;
273 } else {
274 last = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
275 start = (prandom_u32_state(&rnd) >> 4) % last;
276 }
277
278 mas_span.first_index = start;
279 mas_span.last_index = last;
280 mas_span.is_hole = -1;
281 mas_set(&mas, start);
282
283 interval_tree_for_each_span(&span, &root, start, last) {
284 mas_cur_span(&mas, &mas_span);
285
286 WARN_ON_ONCE(span.is_hole != mas_span.is_hole);
287
288 if (span.is_hole) {
289 WARN_ON_ONCE(span.start_hole != mas_span.start_hole);
290 WARN_ON_ONCE(span.last_hole != mas_span.last_hole);
291 } else {
292 WARN_ON_ONCE(span.start_used != mas_span.start_used);
293 WARN_ON_ONCE(span.last_used != mas_span.last_used);
294 }
295 }
296
297 }
298
299 WARN_ON_ONCE(mas.status != ma_overflow);
300
301 /* Cleanup maple tree for each round */
302 mtree_destroy(&tree);
303 /* Cleanup interval tree for each round */
304 for (j = 0; j < nnodes; j++)
305 interval_tree_remove(nodes + j, &root);
306 }
307 return 0;
308}
309#else
310static inline int span_iteration_check(void) {return 0; }
311#endif
312
313static int interval_tree_test_init(void)
314{
315 if (nnodes <= 0) {
316 pr_warn("nnodes must be positive\n");
317 return -EINVAL;
318 }
319 if (nsearches <= 0) {
320 pr_warn("nsearches must be positive\n");
321 return -EINVAL;
322 }
323 if (perf_loops <= 0) {
324 pr_warn("perf_loops must be positive\n");
325 return -EINVAL;
326 }
327 if (search_loops <= 0) {
328 pr_warn("search_loops must be positive\n");
329 return -EINVAL;
330 }
331 if (max_endpoint < 2) {
332 pr_warn("max_endpoint must be at least 2\n");
333 return -EINVAL;
334 }
335
336 nodes = kmalloc_objs(struct interval_tree_node, nnodes);
337 if (!nodes)
338 return -ENOMEM;
339
340 queries = kmalloc_array(nsearches, sizeof(int), GFP_KERNEL);
341 if (!queries) {
342 kfree(nodes);
343 return -ENOMEM;
344 }
345
346 prandom_seed_state(&rnd, seed);
347
348 basic_check();
349 search_check();
350 intersection_range_check();
351 span_iteration_check();
352
353 kfree(queries);
354 kfree(nodes);
355
356 return -EAGAIN; /* Fail will directly unload the module */
357}
358
359static void interval_tree_test_exit(void)
360{
361 printk(KERN_ALERT "test exit\n");
362}
363
364module_init(interval_tree_test_init)
365module_exit(interval_tree_test_exit)
366
367MODULE_LICENSE("GPL");
368MODULE_AUTHOR("Michel Lespinasse");
369MODULE_DESCRIPTION("Interval Tree test");