1 /*
2  * multiorder.c: Multi-order radix tree entry testing
3  * Copyright (c) 2016 Intel Corporation
4  * Author: Ross Zwisler <ross.zwisler@linux.intel.com>
5  * Author: Matthew Wilcox <matthew.r.wilcox@intel.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms and conditions of the GNU General Public License,
9  * version 2, as published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  * more details.
15  */
16 #include <linux/radix-tree.h>
17 #include <linux/slab.h>
18 #include <linux/errno.h>
19 
20 #include "test.h"
21 
22 #define for_each_index(i, base, order) \
23 	for (i = base; i < base + (1 << order); i++)
24 
25 static void __multiorder_tag_test(int index, int order)
26 {
27 	RADIX_TREE(tree, GFP_KERNEL);
28 	int base, err, i;
29 
30 	/* our canonical entry */
31 	base = index & ~((1 << order) - 1);
32 
33 	printv(2, "Multiorder tag test with index %d, canonical entry %d\n",
34 			index, base);
35 
36 	err = item_insert_order(&tree, index, order);
37 	assert(!err);
38 
39 	/*
40 	 * Verify we get collisions for covered indices.  We try and fail to
41 	 * insert an exceptional entry so we don't leak memory via
42 	 * item_insert_order().
43 	 */
44 	for_each_index(i, base, order) {
45 		err = __radix_tree_insert(&tree, i, order,
46 				(void *)(0xA0 | RADIX_TREE_EXCEPTIONAL_ENTRY));
47 		assert(err == -EEXIST);
48 	}
49 
50 	for_each_index(i, base, order) {
51 		assert(!radix_tree_tag_get(&tree, i, 0));
52 		assert(!radix_tree_tag_get(&tree, i, 1));
53 	}
54 
55 	assert(radix_tree_tag_set(&tree, index, 0));
56 
57 	for_each_index(i, base, order) {
58 		assert(radix_tree_tag_get(&tree, i, 0));
59 		assert(!radix_tree_tag_get(&tree, i, 1));
60 	}
61 
62 	assert(tag_tagged_items(&tree, NULL, 0, ~0UL, 10, 0, 1) == 1);
63 	assert(radix_tree_tag_clear(&tree, index, 0));
64 
65 	for_each_index(i, base, order) {
66 		assert(!radix_tree_tag_get(&tree, i, 0));
67 		assert(radix_tree_tag_get(&tree, i, 1));
68 	}
69 
70 	assert(radix_tree_tag_clear(&tree, index, 1));
71 
72 	assert(!radix_tree_tagged(&tree, 0));
73 	assert(!radix_tree_tagged(&tree, 1));
74 
75 	item_kill_tree(&tree);
76 }
77 
78 static void __multiorder_tag_test2(unsigned order, unsigned long index2)
79 {
80 	RADIX_TREE(tree, GFP_KERNEL);
81 	unsigned long index = (1 << order);
82 	index2 += index;
83 
84 	assert(item_insert_order(&tree, 0, order) == 0);
85 	assert(item_insert(&tree, index2) == 0);
86 
87 	assert(radix_tree_tag_set(&tree, 0, 0));
88 	assert(radix_tree_tag_set(&tree, index2, 0));
89 
90 	assert(tag_tagged_items(&tree, NULL, 0, ~0UL, 10, 0, 1) == 2);
91 
92 	item_kill_tree(&tree);
93 }
94 
95 static void multiorder_tag_tests(void)
96 {
97 	int i, j;
98 
99 	/* test multi-order entry for indices 0-7 with no sibling pointers */
100 	__multiorder_tag_test(0, 3);
101 	__multiorder_tag_test(5, 3);
102 
103 	/* test multi-order entry for indices 8-15 with no sibling pointers */
104 	__multiorder_tag_test(8, 3);
105 	__multiorder_tag_test(15, 3);
106 
107 	/*
108 	 * Our order 5 entry covers indices 0-31 in a tree with height=2.
109 	 * This is broken up as follows:
110 	 * 0-7:		canonical entry
111 	 * 8-15:	sibling 1
112 	 * 16-23:	sibling 2
113 	 * 24-31:	sibling 3
114 	 */
115 	__multiorder_tag_test(0, 5);
116 	__multiorder_tag_test(29, 5);
117 
118 	/* same test, but with indices 32-63 */
119 	__multiorder_tag_test(32, 5);
120 	__multiorder_tag_test(44, 5);
121 
122 	/*
123 	 * Our order 8 entry covers indices 0-255 in a tree with height=3.
124 	 * This is broken up as follows:
125 	 * 0-63:	canonical entry
126 	 * 64-127:	sibling 1
127 	 * 128-191:	sibling 2
128 	 * 192-255:	sibling 3
129 	 */
130 	__multiorder_tag_test(0, 8);
131 	__multiorder_tag_test(190, 8);
132 
133 	/* same test, but with indices 256-511 */
134 	__multiorder_tag_test(256, 8);
135 	__multiorder_tag_test(300, 8);
136 
137 	__multiorder_tag_test(0x12345678UL, 8);
138 
139 	for (i = 1; i < 10; i++)
140 		for (j = 0; j < (10 << i); j++)
141 			__multiorder_tag_test2(i, j);
142 }
143 
144 static void multiorder_check(unsigned long index, int order)
145 {
146 	unsigned long i;
147 	unsigned long min = index & ~((1UL << order) - 1);
148 	unsigned long max = min + (1UL << order);
149 	void **slot;
150 	struct item *item2 = item_create(min, order);
151 	RADIX_TREE(tree, GFP_KERNEL);
152 
153 	printv(2, "Multiorder index %ld, order %d\n", index, order);
154 
155 	assert(item_insert_order(&tree, index, order) == 0);
156 
157 	for (i = min; i < max; i++) {
158 		struct item *item = item_lookup(&tree, i);
159 		assert(item != 0);
160 		assert(item->index == index);
161 	}
162 	for (i = 0; i < min; i++)
163 		item_check_absent(&tree, i);
164 	for (i = max; i < 2*max; i++)
165 		item_check_absent(&tree, i);
166 	for (i = min; i < max; i++)
167 		assert(radix_tree_insert(&tree, i, item2) == -EEXIST);
168 
169 	slot = radix_tree_lookup_slot(&tree, index);
170 	free(*slot);
171 	radix_tree_replace_slot(&tree, slot, item2);
172 	for (i = min; i < max; i++) {
173 		struct item *item = item_lookup(&tree, i);
174 		assert(item != 0);
175 		assert(item->index == min);
176 	}
177 
178 	assert(item_delete(&tree, min) != 0);
179 
180 	for (i = 0; i < 2*max; i++)
181 		item_check_absent(&tree, i);
182 }
183 
184 static void multiorder_shrink(unsigned long index, int order)
185 {
186 	unsigned long i;
187 	unsigned long max = 1 << order;
188 	RADIX_TREE(tree, GFP_KERNEL);
189 	struct radix_tree_node *node;
190 
191 	printv(2, "Multiorder shrink index %ld, order %d\n", index, order);
192 
193 	assert(item_insert_order(&tree, 0, order) == 0);
194 
195 	node = tree.rnode;
196 
197 	assert(item_insert(&tree, index) == 0);
198 	assert(node != tree.rnode);
199 
200 	assert(item_delete(&tree, index) != 0);
201 	assert(node == tree.rnode);
202 
203 	for (i = 0; i < max; i++) {
204 		struct item *item = item_lookup(&tree, i);
205 		assert(item != 0);
206 		assert(item->index == 0);
207 	}
208 	for (i = max; i < 2*max; i++)
209 		item_check_absent(&tree, i);
210 
211 	if (!item_delete(&tree, 0)) {
212 		printv(2, "failed to delete index %ld (order %d)\n", index, order);
213 		abort();
214 	}
215 
216 	for (i = 0; i < 2*max; i++)
217 		item_check_absent(&tree, i);
218 }
219 
220 static void multiorder_insert_bug(void)
221 {
222 	RADIX_TREE(tree, GFP_KERNEL);
223 
224 	item_insert(&tree, 0);
225 	radix_tree_tag_set(&tree, 0, 0);
226 	item_insert_order(&tree, 3 << 6, 6);
227 
228 	item_kill_tree(&tree);
229 }
230 
231 void multiorder_iteration(void)
232 {
233 	RADIX_TREE(tree, GFP_KERNEL);
234 	struct radix_tree_iter iter;
235 	void **slot;
236 	int i, j, err;
237 
238 	printv(1, "Multiorder iteration test\n");
239 
240 #define NUM_ENTRIES 11
241 	int index[NUM_ENTRIES] = {0, 2, 4, 8, 16, 32, 34, 36, 64, 72, 128};
242 	int order[NUM_ENTRIES] = {1, 1, 2, 3,  4,  1,  0,  1,  3,  0, 7};
243 
244 	for (i = 0; i < NUM_ENTRIES; i++) {
245 		err = item_insert_order(&tree, index[i], order[i]);
246 		assert(!err);
247 	}
248 
249 	for (j = 0; j < 256; j++) {
250 		for (i = 0; i < NUM_ENTRIES; i++)
251 			if (j <= (index[i] | ((1 << order[i]) - 1)))
252 				break;
253 
254 		radix_tree_for_each_slot(slot, &tree, &iter, j) {
255 			int height = order[i] / RADIX_TREE_MAP_SHIFT;
256 			int shift = height * RADIX_TREE_MAP_SHIFT;
257 			unsigned long mask = (1UL << order[i]) - 1;
258 			struct item *item = *slot;
259 
260 			assert((iter.index | mask) == (index[i] | mask));
261 			assert(iter.shift == shift);
262 			assert(!radix_tree_is_internal_node(item));
263 			assert((item->index | mask) == (index[i] | mask));
264 			assert(item->order == order[i]);
265 			i++;
266 		}
267 	}
268 
269 	item_kill_tree(&tree);
270 }
271 
272 void multiorder_tagged_iteration(void)
273 {
274 	RADIX_TREE(tree, GFP_KERNEL);
275 	struct radix_tree_iter iter;
276 	void **slot;
277 	int i, j;
278 
279 	printv(1, "Multiorder tagged iteration test\n");
280 
281 #define MT_NUM_ENTRIES 9
282 	int index[MT_NUM_ENTRIES] = {0, 2, 4, 16, 32, 40, 64, 72, 128};
283 	int order[MT_NUM_ENTRIES] = {1, 0, 2, 4,  3,  1,  3,  0,   7};
284 
285 #define TAG_ENTRIES 7
286 	int tag_index[TAG_ENTRIES] = {0, 4, 16, 40, 64, 72, 128};
287 
288 	for (i = 0; i < MT_NUM_ENTRIES; i++)
289 		assert(!item_insert_order(&tree, index[i], order[i]));
290 
291 	assert(!radix_tree_tagged(&tree, 1));
292 
293 	for (i = 0; i < TAG_ENTRIES; i++)
294 		assert(radix_tree_tag_set(&tree, tag_index[i], 1));
295 
296 	for (j = 0; j < 256; j++) {
297 		int k;
298 
299 		for (i = 0; i < TAG_ENTRIES; i++) {
300 			for (k = i; index[k] < tag_index[i]; k++)
301 				;
302 			if (j <= (index[k] | ((1 << order[k]) - 1)))
303 				break;
304 		}
305 
306 		radix_tree_for_each_tagged(slot, &tree, &iter, j, 1) {
307 			unsigned long mask;
308 			struct item *item = *slot;
309 			for (k = i; index[k] < tag_index[i]; k++)
310 				;
311 			mask = (1UL << order[k]) - 1;
312 
313 			assert((iter.index | mask) == (tag_index[i] | mask));
314 			assert(!radix_tree_is_internal_node(item));
315 			assert((item->index | mask) == (tag_index[i] | mask));
316 			assert(item->order == order[k]);
317 			i++;
318 		}
319 	}
320 
321 	assert(tag_tagged_items(&tree, NULL, 0, ~0UL, TAG_ENTRIES, 1, 2) ==
322 				TAG_ENTRIES);
323 
324 	for (j = 0; j < 256; j++) {
325 		int mask, k;
326 
327 		for (i = 0; i < TAG_ENTRIES; i++) {
328 			for (k = i; index[k] < tag_index[i]; k++)
329 				;
330 			if (j <= (index[k] | ((1 << order[k]) - 1)))
331 				break;
332 		}
333 
334 		radix_tree_for_each_tagged(slot, &tree, &iter, j, 2) {
335 			struct item *item = *slot;
336 			for (k = i; index[k] < tag_index[i]; k++)
337 				;
338 			mask = (1 << order[k]) - 1;
339 
340 			assert((iter.index | mask) == (tag_index[i] | mask));
341 			assert(!radix_tree_is_internal_node(item));
342 			assert((item->index | mask) == (tag_index[i] | mask));
343 			assert(item->order == order[k]);
344 			i++;
345 		}
346 	}
347 
348 	assert(tag_tagged_items(&tree, NULL, 1, ~0UL, MT_NUM_ENTRIES * 2, 1, 0)
349 			== TAG_ENTRIES);
350 	i = 0;
351 	radix_tree_for_each_tagged(slot, &tree, &iter, 0, 0) {
352 		assert(iter.index == tag_index[i]);
353 		i++;
354 	}
355 
356 	item_kill_tree(&tree);
357 }
358 
359 /*
360  * Basic join checks: make sure we can't find an entry in the tree after
361  * a larger entry has replaced it
362  */
363 static void multiorder_join1(unsigned long index,
364 				unsigned order1, unsigned order2)
365 {
366 	unsigned long loc;
367 	void *item, *item2 = item_create(index + 1, order1);
368 	RADIX_TREE(tree, GFP_KERNEL);
369 
370 	item_insert_order(&tree, index, order2);
371 	item = radix_tree_lookup(&tree, index);
372 	radix_tree_join(&tree, index + 1, order1, item2);
373 	loc = find_item(&tree, item);
374 	if (loc == -1)
375 		free(item);
376 	item = radix_tree_lookup(&tree, index + 1);
377 	assert(item == item2);
378 	item_kill_tree(&tree);
379 }
380 
381 /*
382  * Check that the accounting of exceptional entries is handled correctly
383  * by joining an exceptional entry to a normal pointer.
384  */
385 static void multiorder_join2(unsigned order1, unsigned order2)
386 {
387 	RADIX_TREE(tree, GFP_KERNEL);
388 	struct radix_tree_node *node;
389 	void *item1 = item_create(0, order1);
390 	void *item2;
391 
392 	item_insert_order(&tree, 0, order2);
393 	radix_tree_insert(&tree, 1 << order2, (void *)0x12UL);
394 	item2 = __radix_tree_lookup(&tree, 1 << order2, &node, NULL);
395 	assert(item2 == (void *)0x12UL);
396 	assert(node->exceptional == 1);
397 
398 	item2 = radix_tree_lookup(&tree, 0);
399 	free(item2);
400 
401 	radix_tree_join(&tree, 0, order1, item1);
402 	item2 = __radix_tree_lookup(&tree, 1 << order2, &node, NULL);
403 	assert(item2 == item1);
404 	assert(node->exceptional == 0);
405 	item_kill_tree(&tree);
406 }
407 
408 /*
409  * This test revealed an accounting bug for exceptional entries at one point.
410  * Nodes were being freed back into the pool with an elevated exception count
411  * by radix_tree_join() and then radix_tree_split() was failing to zero the
412  * count of exceptional entries.
413  */
414 static void multiorder_join3(unsigned int order)
415 {
416 	RADIX_TREE(tree, GFP_KERNEL);
417 	struct radix_tree_node *node;
418 	void **slot;
419 	struct radix_tree_iter iter;
420 	unsigned long i;
421 
422 	for (i = 0; i < (1 << order); i++) {
423 		radix_tree_insert(&tree, i, (void *)0x12UL);
424 	}
425 
426 	radix_tree_join(&tree, 0, order, (void *)0x16UL);
427 	rcu_barrier();
428 
429 	radix_tree_split(&tree, 0, 0);
430 
431 	radix_tree_for_each_slot(slot, &tree, &iter, 0) {
432 		radix_tree_iter_replace(&tree, &iter, slot, (void *)0x12UL);
433 	}
434 
435 	__radix_tree_lookup(&tree, 0, &node, NULL);
436 	assert(node->exceptional == node->count);
437 
438 	item_kill_tree(&tree);
439 }
440 
441 static void multiorder_join(void)
442 {
443 	int i, j, idx;
444 
445 	for (idx = 0; idx < 1024; idx = idx * 2 + 3) {
446 		for (i = 1; i < 15; i++) {
447 			for (j = 0; j < i; j++) {
448 				multiorder_join1(idx, i, j);
449 			}
450 		}
451 	}
452 
453 	for (i = 1; i < 15; i++) {
454 		for (j = 0; j < i; j++) {
455 			multiorder_join2(i, j);
456 		}
457 	}
458 
459 	for (i = 3; i < 10; i++) {
460 		multiorder_join3(i);
461 	}
462 }
463 
464 static void check_mem(unsigned old_order, unsigned new_order, unsigned alloc)
465 {
466 	struct radix_tree_preload *rtp = &radix_tree_preloads;
467 	if (rtp->nr != 0)
468 		printv(2, "split(%u %u) remaining %u\n", old_order, new_order,
469 							rtp->nr);
470 	/*
471 	 * Can't check for equality here as some nodes may have been
472 	 * RCU-freed while we ran.  But we should never finish with more
473 	 * nodes allocated since they should have all been preloaded.
474 	 */
475 	if (nr_allocated > alloc)
476 		printv(2, "split(%u %u) allocated %u %u\n", old_order, new_order,
477 							alloc, nr_allocated);
478 }
479 
480 static void __multiorder_split(int old_order, int new_order)
481 {
482 	RADIX_TREE(tree, GFP_ATOMIC);
483 	void **slot;
484 	struct radix_tree_iter iter;
485 	unsigned alloc;
486 	struct item *item;
487 
488 	radix_tree_preload(GFP_KERNEL);
489 	assert(item_insert_order(&tree, 0, old_order) == 0);
490 	radix_tree_preload_end();
491 
492 	/* Wipe out the preloaded cache or it'll confuse check_mem() */
493 	radix_tree_cpu_dead(0);
494 
495 	item = radix_tree_tag_set(&tree, 0, 2);
496 
497 	radix_tree_split_preload(old_order, new_order, GFP_KERNEL);
498 	alloc = nr_allocated;
499 	radix_tree_split(&tree, 0, new_order);
500 	check_mem(old_order, new_order, alloc);
501 	radix_tree_for_each_slot(slot, &tree, &iter, 0) {
502 		radix_tree_iter_replace(&tree, &iter, slot,
503 					item_create(iter.index, new_order));
504 	}
505 	radix_tree_preload_end();
506 
507 	item_kill_tree(&tree);
508 	free(item);
509 }
510 
511 static void __multiorder_split2(int old_order, int new_order)
512 {
513 	RADIX_TREE(tree, GFP_KERNEL);
514 	void **slot;
515 	struct radix_tree_iter iter;
516 	struct radix_tree_node *node;
517 	void *item;
518 
519 	__radix_tree_insert(&tree, 0, old_order, (void *)0x12);
520 
521 	item = __radix_tree_lookup(&tree, 0, &node, NULL);
522 	assert(item == (void *)0x12);
523 	assert(node->exceptional > 0);
524 
525 	radix_tree_split(&tree, 0, new_order);
526 	radix_tree_for_each_slot(slot, &tree, &iter, 0) {
527 		radix_tree_iter_replace(&tree, &iter, slot,
528 					item_create(iter.index, new_order));
529 	}
530 
531 	item = __radix_tree_lookup(&tree, 0, &node, NULL);
532 	assert(item != (void *)0x12);
533 	assert(node->exceptional == 0);
534 
535 	item_kill_tree(&tree);
536 }
537 
538 static void __multiorder_split3(int old_order, int new_order)
539 {
540 	RADIX_TREE(tree, GFP_KERNEL);
541 	void **slot;
542 	struct radix_tree_iter iter;
543 	struct radix_tree_node *node;
544 	void *item;
545 
546 	__radix_tree_insert(&tree, 0, old_order, (void *)0x12);
547 
548 	item = __radix_tree_lookup(&tree, 0, &node, NULL);
549 	assert(item == (void *)0x12);
550 	assert(node->exceptional > 0);
551 
552 	radix_tree_split(&tree, 0, new_order);
553 	radix_tree_for_each_slot(slot, &tree, &iter, 0) {
554 		radix_tree_iter_replace(&tree, &iter, slot, (void *)0x16);
555 	}
556 
557 	item = __radix_tree_lookup(&tree, 0, &node, NULL);
558 	assert(item == (void *)0x16);
559 	assert(node->exceptional > 0);
560 
561 	item_kill_tree(&tree);
562 
563 	__radix_tree_insert(&tree, 0, old_order, (void *)0x12);
564 
565 	item = __radix_tree_lookup(&tree, 0, &node, NULL);
566 	assert(item == (void *)0x12);
567 	assert(node->exceptional > 0);
568 
569 	radix_tree_split(&tree, 0, new_order);
570 	radix_tree_for_each_slot(slot, &tree, &iter, 0) {
571 		if (iter.index == (1 << new_order))
572 			radix_tree_iter_replace(&tree, &iter, slot,
573 						(void *)0x16);
574 		else
575 			radix_tree_iter_replace(&tree, &iter, slot, NULL);
576 	}
577 
578 	item = __radix_tree_lookup(&tree, 1 << new_order, &node, NULL);
579 	assert(item == (void *)0x16);
580 	assert(node->count == node->exceptional);
581 	do {
582 		node = node->parent;
583 		if (!node)
584 			break;
585 		assert(node->count == 1);
586 		assert(node->exceptional == 0);
587 	} while (1);
588 
589 	item_kill_tree(&tree);
590 }
591 
592 static void multiorder_split(void)
593 {
594 	int i, j;
595 
596 	for (i = 3; i < 11; i++)
597 		for (j = 0; j < i; j++) {
598 			__multiorder_split(i, j);
599 			__multiorder_split2(i, j);
600 			__multiorder_split3(i, j);
601 		}
602 }
603 
604 static void multiorder_account(void)
605 {
606 	RADIX_TREE(tree, GFP_KERNEL);
607 	struct radix_tree_node *node;
608 	void **slot;
609 
610 	item_insert_order(&tree, 0, 5);
611 
612 	__radix_tree_insert(&tree, 1 << 5, 5, (void *)0x12);
613 	__radix_tree_lookup(&tree, 0, &node, NULL);
614 	assert(node->count == node->exceptional * 2);
615 	radix_tree_delete(&tree, 1 << 5);
616 	assert(node->exceptional == 0);
617 
618 	__radix_tree_insert(&tree, 1 << 5, 5, (void *)0x12);
619 	__radix_tree_lookup(&tree, 1 << 5, &node, &slot);
620 	assert(node->count == node->exceptional * 2);
621 	__radix_tree_replace(&tree, node, slot, NULL, NULL);
622 	assert(node->exceptional == 0);
623 
624 	item_kill_tree(&tree);
625 }
626 
627 void multiorder_checks(void)
628 {
629 	int i;
630 
631 	for (i = 0; i < 20; i++) {
632 		multiorder_check(200, i);
633 		multiorder_check(0, i);
634 		multiorder_check((1UL << i) + 1, i);
635 	}
636 
637 	for (i = 0; i < 15; i++)
638 		multiorder_shrink((1UL << (i + RADIX_TREE_MAP_SHIFT)), i);
639 
640 	multiorder_insert_bug();
641 	multiorder_tag_tests();
642 	multiorder_iteration();
643 	multiorder_tagged_iteration();
644 	multiorder_join();
645 	multiorder_split();
646 	multiorder_account();
647 
648 	radix_tree_cpu_dead(0);
649 }
650 
651 int __weak main(void)
652 {
653 	radix_tree_init();
654 	multiorder_checks();
655 	return 0;
656 }
657