1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2016 Facebook
4  */
5 #define _GNU_SOURCE
6 #include <stdio.h>
7 #include <unistd.h>
8 #include <errno.h>
9 #include <string.h>
10 #include <assert.h>
11 #include <sched.h>
12 #include <stdlib.h>
13 #include <time.h>
14 
15 #include <sys/wait.h>
16 
17 #include <bpf/bpf.h>
18 #include <bpf/libbpf.h>
19 
20 #include "bpf_util.h"
21 #include "../../../include/linux/filter.h"
22 
23 #define LOCAL_FREE_TARGET	(128)
24 #define PERCPU_FREE_TARGET	(4)
25 
26 static int nr_cpus;
27 
28 static int create_map(int map_type, int map_flags, unsigned int size)
29 {
30 	LIBBPF_OPTS(bpf_map_create_opts, opts, .map_flags = map_flags);
31 	int map_fd;
32 
33 	map_fd = bpf_map_create(map_type, NULL,  sizeof(unsigned long long),
34 				sizeof(unsigned long long), size, &opts);
35 
36 	if (map_fd == -1)
37 		perror("bpf_map_create");
38 
39 	return map_fd;
40 }
41 
42 static int bpf_map_lookup_elem_with_ref_bit(int fd, unsigned long long key,
43 					    void *value)
44 {
45 	struct bpf_insn insns[] = {
46 		BPF_LD_MAP_VALUE(BPF_REG_9, 0, 0),
47 		BPF_LD_MAP_FD(BPF_REG_1, fd),
48 		BPF_LD_IMM64(BPF_REG_3, key),
49 		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
50 		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
51 		BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, 0),
52 		BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
53 		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4),
54 		BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0),
55 		BPF_STX_MEM(BPF_DW, BPF_REG_9, BPF_REG_1, 0),
56 		BPF_MOV64_IMM(BPF_REG_0, 42),
57 		BPF_JMP_IMM(BPF_JA, 0, 0, 1),
58 		BPF_MOV64_IMM(BPF_REG_0, 1),
59 		BPF_EXIT_INSN(),
60 	};
61 	__u8 data[64] = {};
62 	int mfd, pfd, ret, zero = 0;
63 	LIBBPF_OPTS(bpf_test_run_opts, topts,
64 		.data_in = data,
65 		.data_size_in = sizeof(data),
66 		.repeat = 1,
67 	);
68 
69 	mfd = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, sizeof(int), sizeof(__u64), 1, NULL);
70 	if (mfd < 0)
71 		return -1;
72 
73 	insns[0].imm = mfd;
74 
75 	pfd = bpf_prog_load(BPF_PROG_TYPE_SCHED_CLS, NULL, "GPL", insns, ARRAY_SIZE(insns), NULL);
76 	if (pfd < 0) {
77 		close(mfd);
78 		return -1;
79 	}
80 
81 	ret = bpf_prog_test_run_opts(pfd, &topts);
82 	if (ret < 0 || topts.retval != 42) {
83 		ret = -1;
84 	} else {
85 		assert(!bpf_map_lookup_elem(mfd, &zero, value));
86 		ret = 0;
87 	}
88 	close(pfd);
89 	close(mfd);
90 	return ret;
91 }
92 
93 static int map_subset(int map0, int map1)
94 {
95 	unsigned long long next_key = 0;
96 	unsigned long long value0[nr_cpus], value1[nr_cpus];
97 	int ret;
98 
99 	while (!bpf_map_get_next_key(map1, &next_key, &next_key)) {
100 		assert(!bpf_map_lookup_elem(map1, &next_key, value1));
101 		ret = bpf_map_lookup_elem(map0, &next_key, value0);
102 		if (ret) {
103 			printf("key:%llu not found from map. %s(%d)\n",
104 			       next_key, strerror(errno), errno);
105 			return 0;
106 		}
107 		if (value0[0] != value1[0]) {
108 			printf("key:%llu value0:%llu != value1:%llu\n",
109 			       next_key, value0[0], value1[0]);
110 			return 0;
111 		}
112 	}
113 	return 1;
114 }
115 
116 static int map_equal(int lru_map, int expected)
117 {
118 	return map_subset(lru_map, expected) && map_subset(expected, lru_map);
119 }
120 
121 static int sched_next_online(int pid, int *next_to_try)
122 {
123 	cpu_set_t cpuset;
124 	int next = *next_to_try;
125 	int ret = -1;
126 
127 	while (next < nr_cpus) {
128 		CPU_ZERO(&cpuset);
129 		CPU_SET(next, &cpuset);
130 		next++;
131 		if (!sched_setaffinity(pid, sizeof(cpuset), &cpuset)) {
132 			ret = 0;
133 			break;
134 		}
135 	}
136 
137 	*next_to_try = next;
138 	return ret;
139 }
140 
141 /* Size of the LRU map is 2
142  * Add key=1 (+1 key)
143  * Add key=2 (+1 key)
144  * Lookup Key=1
145  * Add Key=3
146  *   => Key=2 will be removed by LRU
147  * Iterate map.  Only found key=1 and key=3
148  */
149 static void test_lru_sanity0(int map_type, int map_flags)
150 {
151 	unsigned long long key, value[nr_cpus];
152 	int lru_map_fd, expected_map_fd;
153 	int next_cpu = 0;
154 
155 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
156 	       map_flags);
157 
158 	assert(sched_next_online(0, &next_cpu) != -1);
159 
160 	if (map_flags & BPF_F_NO_COMMON_LRU)
161 		lru_map_fd = create_map(map_type, map_flags, 2 * nr_cpus);
162 	else
163 		lru_map_fd = create_map(map_type, map_flags, 2);
164 	assert(lru_map_fd != -1);
165 
166 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, 2);
167 	assert(expected_map_fd != -1);
168 
169 	value[0] = 1234;
170 
171 	/* insert key=1 element */
172 
173 	key = 1;
174 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
175 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
176 				    BPF_NOEXIST));
177 
178 	/* BPF_NOEXIST means: add new element if it doesn't exist */
179 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST) == -EEXIST);
180 	/* key=1 already exists */
181 
182 	assert(bpf_map_update_elem(lru_map_fd, &key, value, -1) == -EINVAL);
183 
184 	/* insert key=2 element */
185 
186 	/* check that key=2 is not found */
187 	key = 2;
188 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -ENOENT);
189 
190 	/* BPF_EXIST means: update existing element */
191 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_EXIST) == -ENOENT);
192 	/* key=2 is not there */
193 
194 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
195 
196 	/* insert key=3 element */
197 
198 	/* check that key=3 is not found */
199 	key = 3;
200 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -ENOENT);
201 
202 	/* check that key=1 can be found and mark the ref bit to
203 	 * stop LRU from removing key=1
204 	 */
205 	key = 1;
206 	assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
207 	assert(value[0] == 1234);
208 
209 	key = 3;
210 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
211 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
212 				    BPF_NOEXIST));
213 
214 	/* key=2 has been removed from the LRU */
215 	key = 2;
216 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -ENOENT);
217 
218 	/* lookup elem key=1 and delete it, then check it doesn't exist */
219 	key = 1;
220 	assert(!bpf_map_lookup_and_delete_elem(lru_map_fd, &key, &value));
221 	assert(value[0] == 1234);
222 
223 	/* remove the same element from the expected map */
224 	assert(!bpf_map_delete_elem(expected_map_fd, &key));
225 
226 	assert(map_equal(lru_map_fd, expected_map_fd));
227 
228 	close(expected_map_fd);
229 	close(lru_map_fd);
230 
231 	printf("Pass\n");
232 }
233 
234 /* Size of the LRU map is 1.5*tgt_free
235  * Insert 1 to tgt_free (+tgt_free keys)
236  * Lookup 1 to tgt_free/2
237  * Insert 1+tgt_free to 2*tgt_free (+tgt_free keys)
238  * => 1+tgt_free/2 to LOCALFREE_TARGET will be removed by LRU
239  */
240 static void test_lru_sanity1(int map_type, int map_flags, unsigned int tgt_free)
241 {
242 	unsigned long long key, end_key, value[nr_cpus];
243 	int lru_map_fd, expected_map_fd;
244 	unsigned int batch_size;
245 	unsigned int map_size;
246 	int next_cpu = 0;
247 
248 	if (map_flags & BPF_F_NO_COMMON_LRU)
249 		/* This test is only applicable to common LRU list */
250 		return;
251 
252 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
253 	       map_flags);
254 
255 	assert(sched_next_online(0, &next_cpu) != -1);
256 
257 	batch_size = tgt_free / 2;
258 	assert(batch_size * 2 == tgt_free);
259 
260 	map_size = tgt_free + batch_size;
261 	lru_map_fd = create_map(map_type, map_flags, map_size);
262 	assert(lru_map_fd != -1);
263 
264 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size);
265 	assert(expected_map_fd != -1);
266 
267 	value[0] = 1234;
268 
269 	/* Insert 1 to tgt_free (+tgt_free keys) */
270 	end_key = 1 + tgt_free;
271 	for (key = 1; key < end_key; key++)
272 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
273 					    BPF_NOEXIST));
274 
275 	/* Lookup 1 to tgt_free/2 */
276 	end_key = 1 + batch_size;
277 	for (key = 1; key < end_key; key++) {
278 		assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
279 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
280 					    BPF_NOEXIST));
281 	}
282 
283 	/* Insert 1+tgt_free to 2*tgt_free
284 	 * => 1+tgt_free/2 to LOCALFREE_TARGET will be
285 	 * removed by LRU
286 	 */
287 	key = 1 + tgt_free;
288 	end_key = key + tgt_free;
289 	for (; key < end_key; key++) {
290 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
291 					    BPF_NOEXIST));
292 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
293 					    BPF_NOEXIST));
294 	}
295 
296 	assert(map_equal(lru_map_fd, expected_map_fd));
297 
298 	close(expected_map_fd);
299 	close(lru_map_fd);
300 
301 	printf("Pass\n");
302 }
303 
304 /* Size of the LRU map 1.5 * tgt_free
305  * Insert 1 to tgt_free (+tgt_free keys)
306  * Update 1 to tgt_free/2
307  *   => The original 1 to tgt_free/2 will be removed due to
308  *      the LRU shrink process
309  * Re-insert 1 to tgt_free/2 again and do a lookup immeidately
310  * Insert 1+tgt_free to tgt_free*3/2
311  * Insert 1+tgt_free*3/2 to tgt_free*5/2
312  *   => Key 1+tgt_free to tgt_free*3/2
313  *      will be removed from LRU because it has never
314  *      been lookup and ref bit is not set
315  */
316 static void test_lru_sanity2(int map_type, int map_flags, unsigned int tgt_free)
317 {
318 	unsigned long long key, value[nr_cpus];
319 	unsigned long long end_key;
320 	int lru_map_fd, expected_map_fd;
321 	unsigned int batch_size;
322 	unsigned int map_size;
323 	int next_cpu = 0;
324 
325 	if (map_flags & BPF_F_NO_COMMON_LRU)
326 		/* This test is only applicable to common LRU list */
327 		return;
328 
329 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
330 	       map_flags);
331 
332 	assert(sched_next_online(0, &next_cpu) != -1);
333 
334 	batch_size = tgt_free / 2;
335 	assert(batch_size * 2 == tgt_free);
336 
337 	map_size = tgt_free + batch_size;
338 	lru_map_fd = create_map(map_type, map_flags, map_size);
339 	assert(lru_map_fd != -1);
340 
341 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size);
342 	assert(expected_map_fd != -1);
343 
344 	value[0] = 1234;
345 
346 	/* Insert 1 to tgt_free (+tgt_free keys) */
347 	end_key = 1 + tgt_free;
348 	for (key = 1; key < end_key; key++)
349 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
350 					    BPF_NOEXIST));
351 
352 	/* Any bpf_map_update_elem will require to acquire a new node
353 	 * from LRU first.
354 	 *
355 	 * The local list is running out of free nodes.
356 	 * It gets from the global LRU list which tries to
357 	 * shrink the inactive list to get tgt_free
358 	 * number of free nodes.
359 	 *
360 	 * Hence, the oldest key 1 to tgt_free/2
361 	 * are removed from the LRU list.
362 	 */
363 	key = 1;
364 	if (map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
365 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
366 					    BPF_NOEXIST));
367 		assert(!bpf_map_delete_elem(lru_map_fd, &key));
368 	} else {
369 		assert(bpf_map_update_elem(lru_map_fd, &key, value,
370 					   BPF_EXIST));
371 	}
372 
373 	/* Re-insert 1 to tgt_free/2 again and do a lookup
374 	 * immeidately.
375 	 */
376 	end_key = 1 + batch_size;
377 	value[0] = 4321;
378 	for (key = 1; key < end_key; key++) {
379 		assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -ENOENT);
380 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
381 					    BPF_NOEXIST));
382 		assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
383 		assert(value[0] == 4321);
384 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
385 					    BPF_NOEXIST));
386 	}
387 
388 	value[0] = 1234;
389 
390 	/* Insert 1+tgt_free to tgt_free*3/2 */
391 	end_key = 1 + tgt_free + batch_size;
392 	for (key = 1 + tgt_free; key < end_key; key++)
393 		/* These newly added but not referenced keys will be
394 		 * gone during the next LRU shrink.
395 		 */
396 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
397 					    BPF_NOEXIST));
398 
399 	/* Insert 1+tgt_free*3/2 to  tgt_free*5/2 */
400 	end_key = key + tgt_free;
401 	for (; key < end_key; key++) {
402 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
403 					    BPF_NOEXIST));
404 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
405 					    BPF_NOEXIST));
406 	}
407 
408 	assert(map_equal(lru_map_fd, expected_map_fd));
409 
410 	close(expected_map_fd);
411 	close(lru_map_fd);
412 
413 	printf("Pass\n");
414 }
415 
416 /* Size of the LRU map is 2*tgt_free
417  * It is to test the active/inactive list rotation
418  * Insert 1 to 2*tgt_free (+2*tgt_free keys)
419  * Lookup key 1 to tgt_free*3/2
420  * Add 1+2*tgt_free to tgt_free*5/2 (+tgt_free/2 keys)
421  *  => key 1+tgt_free*3/2 to 2*tgt_free are removed from LRU
422  */
423 static void test_lru_sanity3(int map_type, int map_flags, unsigned int tgt_free)
424 {
425 	unsigned long long key, end_key, value[nr_cpus];
426 	int lru_map_fd, expected_map_fd;
427 	unsigned int batch_size;
428 	unsigned int map_size;
429 	int next_cpu = 0;
430 
431 	if (map_flags & BPF_F_NO_COMMON_LRU)
432 		/* This test is only applicable to common LRU list */
433 		return;
434 
435 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
436 	       map_flags);
437 
438 	assert(sched_next_online(0, &next_cpu) != -1);
439 
440 	batch_size = tgt_free / 2;
441 	assert(batch_size * 2 == tgt_free);
442 
443 	map_size = tgt_free * 2;
444 	lru_map_fd = create_map(map_type, map_flags, map_size);
445 	assert(lru_map_fd != -1);
446 
447 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size);
448 	assert(expected_map_fd != -1);
449 
450 	value[0] = 1234;
451 
452 	/* Insert 1 to 2*tgt_free (+2*tgt_free keys) */
453 	end_key = 1 + (2 * tgt_free);
454 	for (key = 1; key < end_key; key++)
455 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
456 					    BPF_NOEXIST));
457 
458 	/* Lookup key 1 to tgt_free*3/2 */
459 	end_key = tgt_free + batch_size;
460 	for (key = 1; key < end_key; key++) {
461 		assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
462 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
463 					    BPF_NOEXIST));
464 	}
465 
466 	/* Add 1+2*tgt_free to tgt_free*5/2
467 	 * (+tgt_free/2 keys)
468 	 */
469 	key = 2 * tgt_free + 1;
470 	end_key = key + batch_size;
471 	for (; key < end_key; key++) {
472 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
473 					    BPF_NOEXIST));
474 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
475 					    BPF_NOEXIST));
476 	}
477 
478 	assert(map_equal(lru_map_fd, expected_map_fd));
479 
480 	close(expected_map_fd);
481 	close(lru_map_fd);
482 
483 	printf("Pass\n");
484 }
485 
486 /* Test deletion */
487 static void test_lru_sanity4(int map_type, int map_flags, unsigned int tgt_free)
488 {
489 	int lru_map_fd, expected_map_fd;
490 	unsigned long long key, value[nr_cpus];
491 	unsigned long long end_key;
492 	int next_cpu = 0;
493 
494 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
495 	       map_flags);
496 
497 	assert(sched_next_online(0, &next_cpu) != -1);
498 
499 	if (map_flags & BPF_F_NO_COMMON_LRU)
500 		lru_map_fd = create_map(map_type, map_flags,
501 					3 * tgt_free * nr_cpus);
502 	else
503 		lru_map_fd = create_map(map_type, map_flags, 3 * tgt_free);
504 	assert(lru_map_fd != -1);
505 
506 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0,
507 				     3 * tgt_free);
508 	assert(expected_map_fd != -1);
509 
510 	value[0] = 1234;
511 
512 	for (key = 1; key <= 2 * tgt_free; key++)
513 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
514 					    BPF_NOEXIST));
515 
516 	key = 1;
517 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
518 
519 	for (key = 1; key <= tgt_free; key++) {
520 		assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
521 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
522 					    BPF_NOEXIST));
523 	}
524 
525 	for (; key <= 2 * tgt_free; key++) {
526 		assert(!bpf_map_delete_elem(lru_map_fd, &key));
527 		assert(bpf_map_delete_elem(lru_map_fd, &key));
528 	}
529 
530 	end_key = key + 2 * tgt_free;
531 	for (; key < end_key; key++) {
532 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
533 					    BPF_NOEXIST));
534 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
535 					    BPF_NOEXIST));
536 	}
537 
538 	assert(map_equal(lru_map_fd, expected_map_fd));
539 
540 	close(expected_map_fd);
541 	close(lru_map_fd);
542 
543 	printf("Pass\n");
544 }
545 
546 static void do_test_lru_sanity5(unsigned long long last_key, int map_fd)
547 {
548 	unsigned long long key, value[nr_cpus];
549 
550 	/* Ensure the last key inserted by previous CPU can be found */
551 	assert(!bpf_map_lookup_elem_with_ref_bit(map_fd, last_key, value));
552 	value[0] = 1234;
553 
554 	key = last_key + 1;
555 	assert(!bpf_map_update_elem(map_fd, &key, value, BPF_NOEXIST));
556 	assert(!bpf_map_lookup_elem_with_ref_bit(map_fd, key, value));
557 
558 	/* Cannot find the last key because it was removed by LRU */
559 	assert(bpf_map_lookup_elem(map_fd, &last_key, value) == -ENOENT);
560 }
561 
562 /* Test map with only one element */
563 static void test_lru_sanity5(int map_type, int map_flags)
564 {
565 	unsigned long long key, value[nr_cpus];
566 	int next_cpu = 0;
567 	int map_fd;
568 
569 	if (map_flags & BPF_F_NO_COMMON_LRU)
570 		return;
571 
572 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
573 	       map_flags);
574 
575 	map_fd = create_map(map_type, map_flags, 1);
576 	assert(map_fd != -1);
577 
578 	value[0] = 1234;
579 	key = 0;
580 	assert(!bpf_map_update_elem(map_fd, &key, value, BPF_NOEXIST));
581 
582 	while (sched_next_online(0, &next_cpu) != -1) {
583 		pid_t pid;
584 
585 		pid = fork();
586 		if (pid == 0) {
587 			do_test_lru_sanity5(key, map_fd);
588 			exit(0);
589 		} else if (pid == -1) {
590 			printf("couldn't spawn process to test key:%llu\n",
591 			       key);
592 			exit(1);
593 		} else {
594 			int status;
595 
596 			assert(waitpid(pid, &status, 0) == pid);
597 			assert(status == 0);
598 			key++;
599 		}
600 	}
601 
602 	close(map_fd);
603 	/* At least one key should be tested */
604 	assert(key > 0);
605 
606 	printf("Pass\n");
607 }
608 
609 /* Test list rotation for BPF_F_NO_COMMON_LRU map */
610 static void test_lru_sanity6(int map_type, int map_flags, int tgt_free)
611 {
612 	int lru_map_fd, expected_map_fd;
613 	unsigned long long key, value[nr_cpus];
614 	unsigned int map_size = tgt_free * 2;
615 	int next_cpu = 0;
616 
617 	if (!(map_flags & BPF_F_NO_COMMON_LRU))
618 		return;
619 
620 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
621 	       map_flags);
622 
623 	assert(sched_next_online(0, &next_cpu) != -1);
624 
625 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size);
626 	assert(expected_map_fd != -1);
627 
628 	lru_map_fd = create_map(map_type, map_flags, map_size * nr_cpus);
629 	assert(lru_map_fd != -1);
630 
631 	value[0] = 1234;
632 
633 	for (key = 1; key <= tgt_free; key++) {
634 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
635 					    BPF_NOEXIST));
636 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
637 					    BPF_NOEXIST));
638 	}
639 
640 	for (; key <= tgt_free * 2; key++) {
641 		unsigned long long stable_key;
642 
643 		/* Make ref bit sticky for key: [1, tgt_free] */
644 		for (stable_key = 1; stable_key <= tgt_free; stable_key++) {
645 			/* Mark the ref bit */
646 			assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd,
647 								 stable_key, value));
648 		}
649 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
650 					    BPF_NOEXIST));
651 	}
652 
653 	for (; key <= tgt_free * 3; key++) {
654 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
655 					    BPF_NOEXIST));
656 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
657 					    BPF_NOEXIST));
658 	}
659 
660 	assert(map_equal(lru_map_fd, expected_map_fd));
661 
662 	close(expected_map_fd);
663 	close(lru_map_fd);
664 
665 	printf("Pass\n");
666 }
667 
668 /* Size of the LRU map is 2
669  * Add key=1 (+1 key)
670  * Add key=2 (+1 key)
671  * Lookup Key=1 (datapath)
672  * Lookup Key=2 (syscall)
673  * Add Key=3
674  *   => Key=2 will be removed by LRU
675  * Iterate map.  Only found key=1 and key=3
676  */
677 static void test_lru_sanity7(int map_type, int map_flags)
678 {
679 	unsigned long long key, value[nr_cpus];
680 	int lru_map_fd, expected_map_fd;
681 	int next_cpu = 0;
682 
683 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
684 	       map_flags);
685 
686 	assert(sched_next_online(0, &next_cpu) != -1);
687 
688 	if (map_flags & BPF_F_NO_COMMON_LRU)
689 		lru_map_fd = create_map(map_type, map_flags, 2 * nr_cpus);
690 	else
691 		lru_map_fd = create_map(map_type, map_flags, 2);
692 	assert(lru_map_fd != -1);
693 
694 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, 2);
695 	assert(expected_map_fd != -1);
696 
697 	value[0] = 1234;
698 
699 	/* insert key=1 element */
700 
701 	key = 1;
702 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
703 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
704 				    BPF_NOEXIST));
705 
706 	/* BPF_NOEXIST means: add new element if it doesn't exist */
707 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST) == -EEXIST);
708 	/* key=1 already exists */
709 
710 	/* insert key=2 element */
711 
712 	/* check that key=2 is not found */
713 	key = 2;
714 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -ENOENT);
715 
716 	/* BPF_EXIST means: update existing element */
717 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_EXIST) == -ENOENT);
718 	/* key=2 is not there */
719 
720 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
721 
722 	/* insert key=3 element */
723 
724 	/* check that key=3 is not found */
725 	key = 3;
726 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -ENOENT);
727 
728 	/* check that key=1 can be found and mark the ref bit to
729 	 * stop LRU from removing key=1
730 	 */
731 	key = 1;
732 	assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
733 	assert(value[0] == 1234);
734 
735 	/* check that key=2 can be found and do _not_ mark ref bit.
736 	 * this will be evicted on next update.
737 	 */
738 	key = 2;
739 	assert(!bpf_map_lookup_elem(lru_map_fd, &key, value));
740 	assert(value[0] == 1234);
741 
742 	key = 3;
743 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
744 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
745 				    BPF_NOEXIST));
746 
747 	/* key=2 has been removed from the LRU */
748 	key = 2;
749 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -ENOENT);
750 
751 	assert(map_equal(lru_map_fd, expected_map_fd));
752 
753 	close(expected_map_fd);
754 	close(lru_map_fd);
755 
756 	printf("Pass\n");
757 }
758 
759 /* Size of the LRU map is 2
760  * Add key=1 (+1 key)
761  * Add key=2 (+1 key)
762  * Lookup Key=1 (syscall)
763  * Lookup Key=2 (datapath)
764  * Add Key=3
765  *   => Key=1 will be removed by LRU
766  * Iterate map.  Only found key=2 and key=3
767  */
768 static void test_lru_sanity8(int map_type, int map_flags)
769 {
770 	unsigned long long key, value[nr_cpus];
771 	int lru_map_fd, expected_map_fd;
772 	int next_cpu = 0;
773 
774 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
775 	       map_flags);
776 
777 	assert(sched_next_online(0, &next_cpu) != -1);
778 
779 	if (map_flags & BPF_F_NO_COMMON_LRU)
780 		lru_map_fd = create_map(map_type, map_flags, 2 * nr_cpus);
781 	else
782 		lru_map_fd = create_map(map_type, map_flags, 2);
783 	assert(lru_map_fd != -1);
784 
785 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, 2);
786 	assert(expected_map_fd != -1);
787 
788 	value[0] = 1234;
789 
790 	/* insert key=1 element */
791 
792 	key = 1;
793 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
794 
795 	/* BPF_NOEXIST means: add new element if it doesn't exist */
796 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST) == -EEXIST);
797 	/* key=1 already exists */
798 
799 	/* insert key=2 element */
800 
801 	/* check that key=2 is not found */
802 	key = 2;
803 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -ENOENT);
804 
805 	/* BPF_EXIST means: update existing element */
806 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_EXIST) == -ENOENT);
807 	/* key=2 is not there */
808 
809 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
810 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
811 				    BPF_NOEXIST));
812 
813 	/* insert key=3 element */
814 
815 	/* check that key=3 is not found */
816 	key = 3;
817 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -ENOENT);
818 
819 	/* check that key=1 can be found and do _not_ mark ref bit.
820 	 * this will be evicted on next update.
821 	 */
822 	key = 1;
823 	assert(!bpf_map_lookup_elem(lru_map_fd, &key, value));
824 	assert(value[0] == 1234);
825 
826 	/* check that key=2 can be found and mark the ref bit to
827 	 * stop LRU from removing key=2
828 	 */
829 	key = 2;
830 	assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
831 	assert(value[0] == 1234);
832 
833 	key = 3;
834 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
835 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
836 				    BPF_NOEXIST));
837 
838 	/* key=1 has been removed from the LRU */
839 	key = 1;
840 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -ENOENT);
841 
842 	assert(map_equal(lru_map_fd, expected_map_fd));
843 
844 	close(expected_map_fd);
845 	close(lru_map_fd);
846 
847 	printf("Pass\n");
848 }
849 
850 int main(int argc, char **argv)
851 {
852 	int map_types[] = {BPF_MAP_TYPE_LRU_HASH,
853 			     BPF_MAP_TYPE_LRU_PERCPU_HASH};
854 	int map_flags[] = {0, BPF_F_NO_COMMON_LRU};
855 	int t, f;
856 
857 	setbuf(stdout, NULL);
858 
859 	nr_cpus = bpf_num_possible_cpus();
860 	assert(nr_cpus != -1);
861 	printf("nr_cpus:%d\n\n", nr_cpus);
862 
863 	/* Use libbpf 1.0 API mode */
864 	libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
865 
866 	for (f = 0; f < ARRAY_SIZE(map_flags); f++) {
867 		unsigned int tgt_free = (map_flags[f] & BPF_F_NO_COMMON_LRU) ?
868 			PERCPU_FREE_TARGET : LOCAL_FREE_TARGET;
869 
870 		for (t = 0; t < ARRAY_SIZE(map_types); t++) {
871 			test_lru_sanity0(map_types[t], map_flags[f]);
872 			test_lru_sanity1(map_types[t], map_flags[f], tgt_free);
873 			test_lru_sanity2(map_types[t], map_flags[f], tgt_free);
874 			test_lru_sanity3(map_types[t], map_flags[f], tgt_free);
875 			test_lru_sanity4(map_types[t], map_flags[f], tgt_free);
876 			test_lru_sanity5(map_types[t], map_flags[f]);
877 			test_lru_sanity6(map_types[t], map_flags[f], tgt_free);
878 			test_lru_sanity7(map_types[t], map_flags[f]);
879 			test_lru_sanity8(map_types[t], map_flags[f]);
880 
881 			printf("\n");
882 		}
883 	}
884 
885 	return 0;
886 }
887