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 "bpf_rlimit.h"
22 #include "../../../include/linux/filter.h"
23 
24 #define LOCAL_FREE_TARGET	(128)
25 #define PERCPU_FREE_TARGET	(4)
26 
27 static int nr_cpus;
28 
29 static int create_map(int map_type, int map_flags, unsigned int size)
30 {
31 	LIBBPF_OPTS(bpf_map_create_opts, opts, .map_flags = map_flags);
32 	int map_fd;
33 
34 	map_fd = bpf_map_create(map_type, NULL,  sizeof(unsigned long long),
35 				sizeof(unsigned long long), size, &opts);
36 
37 	if (map_fd == -1)
38 		perror("bpf_map_create");
39 
40 	return map_fd;
41 }
42 
43 static int bpf_map_lookup_elem_with_ref_bit(int fd, unsigned long long key,
44 					    void *value)
45 {
46 	struct bpf_insn insns[] = {
47 		BPF_LD_MAP_VALUE(BPF_REG_9, 0, 0),
48 		BPF_LD_MAP_FD(BPF_REG_1, fd),
49 		BPF_LD_IMM64(BPF_REG_3, key),
50 		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
51 		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
52 		BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, 0),
53 		BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
54 		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4),
55 		BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0),
56 		BPF_STX_MEM(BPF_DW, BPF_REG_9, BPF_REG_1, 0),
57 		BPF_MOV64_IMM(BPF_REG_0, 42),
58 		BPF_JMP_IMM(BPF_JA, 0, 0, 1),
59 		BPF_MOV64_IMM(BPF_REG_0, 1),
60 		BPF_EXIT_INSN(),
61 	};
62 	__u8 data[64] = {};
63 	int mfd, pfd, ret, zero = 0;
64 	__u32 retval = 0;
65 
66 	mfd = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, sizeof(int), sizeof(__u64), 1, NULL);
67 	if (mfd < 0)
68 		return -1;
69 
70 	insns[0].imm = mfd;
71 
72 	pfd = bpf_prog_load(BPF_PROG_TYPE_SCHED_CLS, NULL, "GPL", insns, ARRAY_SIZE(insns), NULL);
73 	if (pfd < 0) {
74 		close(mfd);
75 		return -1;
76 	}
77 
78 	ret = bpf_prog_test_run(pfd, 1, data, sizeof(data),
79 				NULL, NULL, &retval, NULL);
80 	if (ret < 0 || retval != 42) {
81 		ret = -1;
82 	} else {
83 		assert(!bpf_map_lookup_elem(mfd, &zero, value));
84 		ret = 0;
85 	}
86 	close(pfd);
87 	close(mfd);
88 	return ret;
89 }
90 
91 static int map_subset(int map0, int map1)
92 {
93 	unsigned long long next_key = 0;
94 	unsigned long long value0[nr_cpus], value1[nr_cpus];
95 	int ret;
96 
97 	while (!bpf_map_get_next_key(map1, &next_key, &next_key)) {
98 		assert(!bpf_map_lookup_elem(map1, &next_key, value1));
99 		ret = bpf_map_lookup_elem(map0, &next_key, value0);
100 		if (ret) {
101 			printf("key:%llu not found from map. %s(%d)\n",
102 			       next_key, strerror(errno), errno);
103 			return 0;
104 		}
105 		if (value0[0] != value1[0]) {
106 			printf("key:%llu value0:%llu != value1:%llu\n",
107 			       next_key, value0[0], value1[0]);
108 			return 0;
109 		}
110 	}
111 	return 1;
112 }
113 
114 static int map_equal(int lru_map, int expected)
115 {
116 	return map_subset(lru_map, expected) && map_subset(expected, lru_map);
117 }
118 
119 static int sched_next_online(int pid, int *next_to_try)
120 {
121 	cpu_set_t cpuset;
122 	int next = *next_to_try;
123 	int ret = -1;
124 
125 	while (next < nr_cpus) {
126 		CPU_ZERO(&cpuset);
127 		CPU_SET(next++, &cpuset);
128 		if (!sched_setaffinity(pid, sizeof(cpuset), &cpuset)) {
129 			ret = 0;
130 			break;
131 		}
132 	}
133 
134 	*next_to_try = next;
135 	return ret;
136 }
137 
138 /* Size of the LRU map is 2
139  * Add key=1 (+1 key)
140  * Add key=2 (+1 key)
141  * Lookup Key=1
142  * Add Key=3
143  *   => Key=2 will be removed by LRU
144  * Iterate map.  Only found key=1 and key=3
145  */
146 static void test_lru_sanity0(int map_type, int map_flags)
147 {
148 	unsigned long long key, value[nr_cpus];
149 	int lru_map_fd, expected_map_fd;
150 	int next_cpu = 0;
151 
152 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
153 	       map_flags);
154 
155 	assert(sched_next_online(0, &next_cpu) != -1);
156 
157 	if (map_flags & BPF_F_NO_COMMON_LRU)
158 		lru_map_fd = create_map(map_type, map_flags, 2 * nr_cpus);
159 	else
160 		lru_map_fd = create_map(map_type, map_flags, 2);
161 	assert(lru_map_fd != -1);
162 
163 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, 2);
164 	assert(expected_map_fd != -1);
165 
166 	value[0] = 1234;
167 
168 	/* insert key=1 element */
169 
170 	key = 1;
171 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
172 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
173 				    BPF_NOEXIST));
174 
175 	/* BPF_NOEXIST means: add new element if it doesn't exist */
176 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST) == -1
177 	       /* key=1 already exists */
178 	       && errno == EEXIST);
179 
180 	assert(bpf_map_update_elem(lru_map_fd, &key, value, -1) == -1 &&
181 	       errno == EINVAL);
182 
183 	/* insert key=2 element */
184 
185 	/* check that key=2 is not found */
186 	key = 2;
187 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
188 	       errno == ENOENT);
189 
190 	/* BPF_EXIST means: update existing element */
191 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_EXIST) == -1 &&
192 	       /* key=2 is not there */
193 	       errno == ENOENT);
194 
195 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
196 
197 	/* insert key=3 element */
198 
199 	/* check that key=3 is not found */
200 	key = 3;
201 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
202 	       errno == ENOENT);
203 
204 	/* check that key=1 can be found and mark the ref bit to
205 	 * stop LRU from removing key=1
206 	 */
207 	key = 1;
208 	assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
209 	assert(value[0] == 1234);
210 
211 	key = 3;
212 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
213 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
214 				    BPF_NOEXIST));
215 
216 	/* key=2 has been removed from the LRU */
217 	key = 2;
218 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
219 	       errno == ENOENT);
220 
221 	/* lookup elem key=1 and delete it, then check it doesn't exist */
222 	key = 1;
223 	assert(!bpf_map_lookup_and_delete_elem(lru_map_fd, &key, &value));
224 	assert(value[0] == 1234);
225 
226 	/* remove the same element from the expected map */
227 	assert(!bpf_map_delete_elem(expected_map_fd, &key));
228 
229 	assert(map_equal(lru_map_fd, expected_map_fd));
230 
231 	close(expected_map_fd);
232 	close(lru_map_fd);
233 
234 	printf("Pass\n");
235 }
236 
237 /* Size of the LRU map is 1.5*tgt_free
238  * Insert 1 to tgt_free (+tgt_free keys)
239  * Lookup 1 to tgt_free/2
240  * Insert 1+tgt_free to 2*tgt_free (+tgt_free keys)
241  * => 1+tgt_free/2 to LOCALFREE_TARGET will be removed by LRU
242  */
243 static void test_lru_sanity1(int map_type, int map_flags, unsigned int tgt_free)
244 {
245 	unsigned long long key, end_key, value[nr_cpus];
246 	int lru_map_fd, expected_map_fd;
247 	unsigned int batch_size;
248 	unsigned int map_size;
249 	int next_cpu = 0;
250 
251 	if (map_flags & BPF_F_NO_COMMON_LRU)
252 		/* This test is only applicable to common LRU list */
253 		return;
254 
255 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
256 	       map_flags);
257 
258 	assert(sched_next_online(0, &next_cpu) != -1);
259 
260 	batch_size = tgt_free / 2;
261 	assert(batch_size * 2 == tgt_free);
262 
263 	map_size = tgt_free + batch_size;
264 	lru_map_fd = create_map(map_type, map_flags, map_size);
265 	assert(lru_map_fd != -1);
266 
267 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size);
268 	assert(expected_map_fd != -1);
269 
270 	value[0] = 1234;
271 
272 	/* Insert 1 to tgt_free (+tgt_free keys) */
273 	end_key = 1 + tgt_free;
274 	for (key = 1; key < end_key; key++)
275 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
276 					    BPF_NOEXIST));
277 
278 	/* Lookup 1 to tgt_free/2 */
279 	end_key = 1 + batch_size;
280 	for (key = 1; key < end_key; key++) {
281 		assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
282 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
283 					    BPF_NOEXIST));
284 	}
285 
286 	/* Insert 1+tgt_free to 2*tgt_free
287 	 * => 1+tgt_free/2 to LOCALFREE_TARGET will be
288 	 * removed by LRU
289 	 */
290 	key = 1 + tgt_free;
291 	end_key = key + tgt_free;
292 	for (; key < end_key; key++) {
293 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
294 					    BPF_NOEXIST));
295 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
296 					    BPF_NOEXIST));
297 	}
298 
299 	assert(map_equal(lru_map_fd, expected_map_fd));
300 
301 	close(expected_map_fd);
302 	close(lru_map_fd);
303 
304 	printf("Pass\n");
305 }
306 
307 /* Size of the LRU map 1.5 * tgt_free
308  * Insert 1 to tgt_free (+tgt_free keys)
309  * Update 1 to tgt_free/2
310  *   => The original 1 to tgt_free/2 will be removed due to
311  *      the LRU shrink process
312  * Re-insert 1 to tgt_free/2 again and do a lookup immeidately
313  * Insert 1+tgt_free to tgt_free*3/2
314  * Insert 1+tgt_free*3/2 to tgt_free*5/2
315  *   => Key 1+tgt_free to tgt_free*3/2
316  *      will be removed from LRU because it has never
317  *      been lookup and ref bit is not set
318  */
319 static void test_lru_sanity2(int map_type, int map_flags, unsigned int tgt_free)
320 {
321 	unsigned long long key, value[nr_cpus];
322 	unsigned long long end_key;
323 	int lru_map_fd, expected_map_fd;
324 	unsigned int batch_size;
325 	unsigned int map_size;
326 	int next_cpu = 0;
327 
328 	if (map_flags & BPF_F_NO_COMMON_LRU)
329 		/* This test is only applicable to common LRU list */
330 		return;
331 
332 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
333 	       map_flags);
334 
335 	assert(sched_next_online(0, &next_cpu) != -1);
336 
337 	batch_size = tgt_free / 2;
338 	assert(batch_size * 2 == tgt_free);
339 
340 	map_size = tgt_free + batch_size;
341 	lru_map_fd = create_map(map_type, map_flags, map_size);
342 	assert(lru_map_fd != -1);
343 
344 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size);
345 	assert(expected_map_fd != -1);
346 
347 	value[0] = 1234;
348 
349 	/* Insert 1 to tgt_free (+tgt_free keys) */
350 	end_key = 1 + tgt_free;
351 	for (key = 1; key < end_key; key++)
352 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
353 					    BPF_NOEXIST));
354 
355 	/* Any bpf_map_update_elem will require to acquire a new node
356 	 * from LRU first.
357 	 *
358 	 * The local list is running out of free nodes.
359 	 * It gets from the global LRU list which tries to
360 	 * shrink the inactive list to get tgt_free
361 	 * number of free nodes.
362 	 *
363 	 * Hence, the oldest key 1 to tgt_free/2
364 	 * are removed from the LRU list.
365 	 */
366 	key = 1;
367 	if (map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
368 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
369 					    BPF_NOEXIST));
370 		assert(!bpf_map_delete_elem(lru_map_fd, &key));
371 	} else {
372 		assert(bpf_map_update_elem(lru_map_fd, &key, value,
373 					   BPF_EXIST));
374 	}
375 
376 	/* Re-insert 1 to tgt_free/2 again and do a lookup
377 	 * immeidately.
378 	 */
379 	end_key = 1 + batch_size;
380 	value[0] = 4321;
381 	for (key = 1; key < end_key; key++) {
382 		assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
383 		       errno == ENOENT);
384 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
385 					    BPF_NOEXIST));
386 		assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
387 		assert(value[0] == 4321);
388 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
389 					    BPF_NOEXIST));
390 	}
391 
392 	value[0] = 1234;
393 
394 	/* Insert 1+tgt_free to tgt_free*3/2 */
395 	end_key = 1 + tgt_free + batch_size;
396 	for (key = 1 + tgt_free; key < end_key; key++)
397 		/* These newly added but not referenced keys will be
398 		 * gone during the next LRU shrink.
399 		 */
400 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
401 					    BPF_NOEXIST));
402 
403 	/* Insert 1+tgt_free*3/2 to  tgt_free*5/2 */
404 	end_key = key + tgt_free;
405 	for (; key < end_key; key++) {
406 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
407 					    BPF_NOEXIST));
408 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
409 					    BPF_NOEXIST));
410 	}
411 
412 	assert(map_equal(lru_map_fd, expected_map_fd));
413 
414 	close(expected_map_fd);
415 	close(lru_map_fd);
416 
417 	printf("Pass\n");
418 }
419 
420 /* Size of the LRU map is 2*tgt_free
421  * It is to test the active/inactive list rotation
422  * Insert 1 to 2*tgt_free (+2*tgt_free keys)
423  * Lookup key 1 to tgt_free*3/2
424  * Add 1+2*tgt_free to tgt_free*5/2 (+tgt_free/2 keys)
425  *  => key 1+tgt_free*3/2 to 2*tgt_free are removed from LRU
426  */
427 static void test_lru_sanity3(int map_type, int map_flags, unsigned int tgt_free)
428 {
429 	unsigned long long key, end_key, value[nr_cpus];
430 	int lru_map_fd, expected_map_fd;
431 	unsigned int batch_size;
432 	unsigned int map_size;
433 	int next_cpu = 0;
434 
435 	if (map_flags & BPF_F_NO_COMMON_LRU)
436 		/* This test is only applicable to common LRU list */
437 		return;
438 
439 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
440 	       map_flags);
441 
442 	assert(sched_next_online(0, &next_cpu) != -1);
443 
444 	batch_size = tgt_free / 2;
445 	assert(batch_size * 2 == tgt_free);
446 
447 	map_size = tgt_free * 2;
448 	lru_map_fd = create_map(map_type, map_flags, map_size);
449 	assert(lru_map_fd != -1);
450 
451 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size);
452 	assert(expected_map_fd != -1);
453 
454 	value[0] = 1234;
455 
456 	/* Insert 1 to 2*tgt_free (+2*tgt_free keys) */
457 	end_key = 1 + (2 * tgt_free);
458 	for (key = 1; key < end_key; key++)
459 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
460 					    BPF_NOEXIST));
461 
462 	/* Lookup key 1 to tgt_free*3/2 */
463 	end_key = tgt_free + batch_size;
464 	for (key = 1; key < end_key; key++) {
465 		assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
466 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
467 					    BPF_NOEXIST));
468 	}
469 
470 	/* Add 1+2*tgt_free to tgt_free*5/2
471 	 * (+tgt_free/2 keys)
472 	 */
473 	key = 2 * tgt_free + 1;
474 	end_key = key + batch_size;
475 	for (; key < end_key; key++) {
476 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
477 					    BPF_NOEXIST));
478 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
479 					    BPF_NOEXIST));
480 	}
481 
482 	assert(map_equal(lru_map_fd, expected_map_fd));
483 
484 	close(expected_map_fd);
485 	close(lru_map_fd);
486 
487 	printf("Pass\n");
488 }
489 
490 /* Test deletion */
491 static void test_lru_sanity4(int map_type, int map_flags, unsigned int tgt_free)
492 {
493 	int lru_map_fd, expected_map_fd;
494 	unsigned long long key, value[nr_cpus];
495 	unsigned long long end_key;
496 	int next_cpu = 0;
497 
498 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
499 	       map_flags);
500 
501 	assert(sched_next_online(0, &next_cpu) != -1);
502 
503 	if (map_flags & BPF_F_NO_COMMON_LRU)
504 		lru_map_fd = create_map(map_type, map_flags,
505 					3 * tgt_free * nr_cpus);
506 	else
507 		lru_map_fd = create_map(map_type, map_flags, 3 * tgt_free);
508 	assert(lru_map_fd != -1);
509 
510 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0,
511 				     3 * tgt_free);
512 	assert(expected_map_fd != -1);
513 
514 	value[0] = 1234;
515 
516 	for (key = 1; key <= 2 * tgt_free; key++)
517 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
518 					    BPF_NOEXIST));
519 
520 	key = 1;
521 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
522 
523 	for (key = 1; key <= tgt_free; key++) {
524 		assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
525 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
526 					    BPF_NOEXIST));
527 	}
528 
529 	for (; key <= 2 * tgt_free; key++) {
530 		assert(!bpf_map_delete_elem(lru_map_fd, &key));
531 		assert(bpf_map_delete_elem(lru_map_fd, &key));
532 	}
533 
534 	end_key = key + 2 * tgt_free;
535 	for (; key < end_key; key++) {
536 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
537 					    BPF_NOEXIST));
538 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
539 					    BPF_NOEXIST));
540 	}
541 
542 	assert(map_equal(lru_map_fd, expected_map_fd));
543 
544 	close(expected_map_fd);
545 	close(lru_map_fd);
546 
547 	printf("Pass\n");
548 }
549 
550 static void do_test_lru_sanity5(unsigned long long last_key, int map_fd)
551 {
552 	unsigned long long key, value[nr_cpus];
553 
554 	/* Ensure the last key inserted by previous CPU can be found */
555 	assert(!bpf_map_lookup_elem_with_ref_bit(map_fd, last_key, value));
556 	value[0] = 1234;
557 
558 	key = last_key + 1;
559 	assert(!bpf_map_update_elem(map_fd, &key, value, BPF_NOEXIST));
560 	assert(!bpf_map_lookup_elem_with_ref_bit(map_fd, key, value));
561 
562 	/* Cannot find the last key because it was removed by LRU */
563 	assert(bpf_map_lookup_elem(map_fd, &last_key, value) == -1 &&
564 	       errno == ENOENT);
565 }
566 
567 /* Test map with only one element */
568 static void test_lru_sanity5(int map_type, int map_flags)
569 {
570 	unsigned long long key, value[nr_cpus];
571 	int next_cpu = 0;
572 	int map_fd;
573 
574 	if (map_flags & BPF_F_NO_COMMON_LRU)
575 		return;
576 
577 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
578 	       map_flags);
579 
580 	map_fd = create_map(map_type, map_flags, 1);
581 	assert(map_fd != -1);
582 
583 	value[0] = 1234;
584 	key = 0;
585 	assert(!bpf_map_update_elem(map_fd, &key, value, BPF_NOEXIST));
586 
587 	while (sched_next_online(0, &next_cpu) != -1) {
588 		pid_t pid;
589 
590 		pid = fork();
591 		if (pid == 0) {
592 			do_test_lru_sanity5(key, map_fd);
593 			exit(0);
594 		} else if (pid == -1) {
595 			printf("couldn't spawn process to test key:%llu\n",
596 			       key);
597 			exit(1);
598 		} else {
599 			int status;
600 
601 			assert(waitpid(pid, &status, 0) == pid);
602 			assert(status == 0);
603 			key++;
604 		}
605 	}
606 
607 	close(map_fd);
608 	/* At least one key should be tested */
609 	assert(key > 0);
610 
611 	printf("Pass\n");
612 }
613 
614 /* Test list rotation for BPF_F_NO_COMMON_LRU map */
615 static void test_lru_sanity6(int map_type, int map_flags, int tgt_free)
616 {
617 	int lru_map_fd, expected_map_fd;
618 	unsigned long long key, value[nr_cpus];
619 	unsigned int map_size = tgt_free * 2;
620 	int next_cpu = 0;
621 
622 	if (!(map_flags & BPF_F_NO_COMMON_LRU))
623 		return;
624 
625 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
626 	       map_flags);
627 
628 	assert(sched_next_online(0, &next_cpu) != -1);
629 
630 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size);
631 	assert(expected_map_fd != -1);
632 
633 	lru_map_fd = create_map(map_type, map_flags, map_size * nr_cpus);
634 	assert(lru_map_fd != -1);
635 
636 	value[0] = 1234;
637 
638 	for (key = 1; key <= tgt_free; key++) {
639 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
640 					    BPF_NOEXIST));
641 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
642 					    BPF_NOEXIST));
643 	}
644 
645 	for (; key <= tgt_free * 2; key++) {
646 		unsigned long long stable_key;
647 
648 		/* Make ref bit sticky for key: [1, tgt_free] */
649 		for (stable_key = 1; stable_key <= tgt_free; stable_key++) {
650 			/* Mark the ref bit */
651 			assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd,
652 								 stable_key, value));
653 		}
654 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
655 					    BPF_NOEXIST));
656 	}
657 
658 	for (; key <= tgt_free * 3; key++) {
659 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
660 					    BPF_NOEXIST));
661 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
662 					    BPF_NOEXIST));
663 	}
664 
665 	assert(map_equal(lru_map_fd, expected_map_fd));
666 
667 	close(expected_map_fd);
668 	close(lru_map_fd);
669 
670 	printf("Pass\n");
671 }
672 
673 /* Size of the LRU map is 2
674  * Add key=1 (+1 key)
675  * Add key=2 (+1 key)
676  * Lookup Key=1 (datapath)
677  * Lookup Key=2 (syscall)
678  * Add Key=3
679  *   => Key=2 will be removed by LRU
680  * Iterate map.  Only found key=1 and key=3
681  */
682 static void test_lru_sanity7(int map_type, int map_flags)
683 {
684 	unsigned long long key, value[nr_cpus];
685 	int lru_map_fd, expected_map_fd;
686 	int next_cpu = 0;
687 
688 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
689 	       map_flags);
690 
691 	assert(sched_next_online(0, &next_cpu) != -1);
692 
693 	if (map_flags & BPF_F_NO_COMMON_LRU)
694 		lru_map_fd = create_map(map_type, map_flags, 2 * nr_cpus);
695 	else
696 		lru_map_fd = create_map(map_type, map_flags, 2);
697 	assert(lru_map_fd != -1);
698 
699 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, 2);
700 	assert(expected_map_fd != -1);
701 
702 	value[0] = 1234;
703 
704 	/* insert key=1 element */
705 
706 	key = 1;
707 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
708 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
709 				    BPF_NOEXIST));
710 
711 	/* BPF_NOEXIST means: add new element if it doesn't exist */
712 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST) == -1
713 	       /* key=1 already exists */
714 	       && errno == EEXIST);
715 
716 	/* insert key=2 element */
717 
718 	/* check that key=2 is not found */
719 	key = 2;
720 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
721 	       errno == ENOENT);
722 
723 	/* BPF_EXIST means: update existing element */
724 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_EXIST) == -1 &&
725 	       /* key=2 is not there */
726 	       errno == ENOENT);
727 
728 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
729 
730 	/* insert key=3 element */
731 
732 	/* check that key=3 is not found */
733 	key = 3;
734 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
735 	       errno == ENOENT);
736 
737 	/* check that key=1 can be found and mark the ref bit to
738 	 * stop LRU from removing key=1
739 	 */
740 	key = 1;
741 	assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
742 	assert(value[0] == 1234);
743 
744 	/* check that key=2 can be found and do _not_ mark ref bit.
745 	 * this will be evicted on next update.
746 	 */
747 	key = 2;
748 	assert(!bpf_map_lookup_elem(lru_map_fd, &key, value));
749 	assert(value[0] == 1234);
750 
751 	key = 3;
752 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
753 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
754 				    BPF_NOEXIST));
755 
756 	/* key=2 has been removed from the LRU */
757 	key = 2;
758 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
759 	       errno == ENOENT);
760 
761 	assert(map_equal(lru_map_fd, expected_map_fd));
762 
763 	close(expected_map_fd);
764 	close(lru_map_fd);
765 
766 	printf("Pass\n");
767 }
768 
769 /* Size of the LRU map is 2
770  * Add key=1 (+1 key)
771  * Add key=2 (+1 key)
772  * Lookup Key=1 (syscall)
773  * Lookup Key=2 (datapath)
774  * Add Key=3
775  *   => Key=1 will be removed by LRU
776  * Iterate map.  Only found key=2 and key=3
777  */
778 static void test_lru_sanity8(int map_type, int map_flags)
779 {
780 	unsigned long long key, value[nr_cpus];
781 	int lru_map_fd, expected_map_fd;
782 	int next_cpu = 0;
783 
784 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
785 	       map_flags);
786 
787 	assert(sched_next_online(0, &next_cpu) != -1);
788 
789 	if (map_flags & BPF_F_NO_COMMON_LRU)
790 		lru_map_fd = create_map(map_type, map_flags, 2 * nr_cpus);
791 	else
792 		lru_map_fd = create_map(map_type, map_flags, 2);
793 	assert(lru_map_fd != -1);
794 
795 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, 2);
796 	assert(expected_map_fd != -1);
797 
798 	value[0] = 1234;
799 
800 	/* insert key=1 element */
801 
802 	key = 1;
803 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
804 
805 	/* BPF_NOEXIST means: add new element if it doesn't exist */
806 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST) == -1
807 	       /* key=1 already exists */
808 	       && errno == EEXIST);
809 
810 	/* insert key=2 element */
811 
812 	/* check that key=2 is not found */
813 	key = 2;
814 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
815 	       errno == ENOENT);
816 
817 	/* BPF_EXIST means: update existing element */
818 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_EXIST) == -1 &&
819 	       /* key=2 is not there */
820 	       errno == ENOENT);
821 
822 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
823 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
824 				    BPF_NOEXIST));
825 
826 	/* insert key=3 element */
827 
828 	/* check that key=3 is not found */
829 	key = 3;
830 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
831 	       errno == ENOENT);
832 
833 	/* check that key=1 can be found and do _not_ mark ref bit.
834 	 * this will be evicted on next update.
835 	 */
836 	key = 1;
837 	assert(!bpf_map_lookup_elem(lru_map_fd, &key, value));
838 	assert(value[0] == 1234);
839 
840 	/* check that key=2 can be found and mark the ref bit to
841 	 * stop LRU from removing key=2
842 	 */
843 	key = 2;
844 	assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
845 	assert(value[0] == 1234);
846 
847 	key = 3;
848 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
849 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
850 				    BPF_NOEXIST));
851 
852 	/* key=1 has been removed from the LRU */
853 	key = 1;
854 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
855 	       errno == ENOENT);
856 
857 	assert(map_equal(lru_map_fd, expected_map_fd));
858 
859 	close(expected_map_fd);
860 	close(lru_map_fd);
861 
862 	printf("Pass\n");
863 }
864 
865 int main(int argc, char **argv)
866 {
867 	int map_types[] = {BPF_MAP_TYPE_LRU_HASH,
868 			     BPF_MAP_TYPE_LRU_PERCPU_HASH};
869 	int map_flags[] = {0, BPF_F_NO_COMMON_LRU};
870 	int t, f;
871 
872 	setbuf(stdout, NULL);
873 
874 	nr_cpus = bpf_num_possible_cpus();
875 	assert(nr_cpus != -1);
876 	printf("nr_cpus:%d\n\n", nr_cpus);
877 
878 	for (f = 0; f < sizeof(map_flags) / sizeof(*map_flags); f++) {
879 		unsigned int tgt_free = (map_flags[f] & BPF_F_NO_COMMON_LRU) ?
880 			PERCPU_FREE_TARGET : LOCAL_FREE_TARGET;
881 
882 		for (t = 0; t < sizeof(map_types) / sizeof(*map_types); t++) {
883 			test_lru_sanity0(map_types[t], map_flags[f]);
884 			test_lru_sanity1(map_types[t], map_flags[f], tgt_free);
885 			test_lru_sanity2(map_types[t], map_flags[f], tgt_free);
886 			test_lru_sanity3(map_types[t], map_flags[f], tgt_free);
887 			test_lru_sanity4(map_types[t], map_flags[f], tgt_free);
888 			test_lru_sanity5(map_types[t], map_flags[f]);
889 			test_lru_sanity6(map_types[t], map_flags[f], tgt_free);
890 			test_lru_sanity7(map_types[t], map_flags[f]);
891 			test_lru_sanity8(map_types[t], map_flags[f]);
892 
893 			printf("\n");
894 		}
895 	}
896 
897 	return 0;
898 }
899