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 	int map_fd;
32 
33 	map_fd = bpf_create_map(map_type, sizeof(unsigned long long),
34 				sizeof(unsigned long long), size, map_flags);
35 
36 	if (map_fd == -1)
37 		perror("bpf_create_map");
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_load_program_attr prog;
46 	struct bpf_create_map_attr map;
47 	struct bpf_insn insns[] = {
48 		BPF_LD_MAP_VALUE(BPF_REG_9, 0, 0),
49 		BPF_LD_MAP_FD(BPF_REG_1, fd),
50 		BPF_LD_IMM64(BPF_REG_3, key),
51 		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
52 		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
53 		BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, 0),
54 		BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
55 		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4),
56 		BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0),
57 		BPF_STX_MEM(BPF_DW, BPF_REG_9, BPF_REG_1, 0),
58 		BPF_MOV64_IMM(BPF_REG_0, 42),
59 		BPF_JMP_IMM(BPF_JA, 0, 0, 1),
60 		BPF_MOV64_IMM(BPF_REG_0, 1),
61 		BPF_EXIT_INSN(),
62 	};
63 	__u8 data[64] = {};
64 	int mfd, pfd, ret, zero = 0;
65 	__u32 retval = 0;
66 
67 	memset(&map, 0, sizeof(map));
68 	map.map_type = BPF_MAP_TYPE_ARRAY;
69 	map.key_size = sizeof(int);
70 	map.value_size = sizeof(unsigned long long);
71 	map.max_entries = 1;
72 
73 	mfd = bpf_create_map_xattr(&map);
74 	if (mfd < 0)
75 		return -1;
76 
77 	insns[0].imm = mfd;
78 
79 	memset(&prog, 0, sizeof(prog));
80 	prog.prog_type = BPF_PROG_TYPE_SCHED_CLS;
81 	prog.insns = insns;
82 	prog.insns_cnt = ARRAY_SIZE(insns);
83 	prog.license = "GPL";
84 
85 	pfd = bpf_load_program_xattr(&prog, NULL, 0);
86 	if (pfd < 0) {
87 		close(mfd);
88 		return -1;
89 	}
90 
91 	ret = bpf_prog_test_run(pfd, 1, data, sizeof(data),
92 				NULL, NULL, &retval, NULL);
93 	if (ret < 0 || retval != 42) {
94 		ret = -1;
95 	} else {
96 		assert(!bpf_map_lookup_elem(mfd, &zero, value));
97 		ret = 0;
98 	}
99 	close(pfd);
100 	close(mfd);
101 	return ret;
102 }
103 
104 static int map_subset(int map0, int map1)
105 {
106 	unsigned long long next_key = 0;
107 	unsigned long long value0[nr_cpus], value1[nr_cpus];
108 	int ret;
109 
110 	while (!bpf_map_get_next_key(map1, &next_key, &next_key)) {
111 		assert(!bpf_map_lookup_elem(map1, &next_key, value1));
112 		ret = bpf_map_lookup_elem(map0, &next_key, value0);
113 		if (ret) {
114 			printf("key:%llu not found from map. %s(%d)\n",
115 			       next_key, strerror(errno), errno);
116 			return 0;
117 		}
118 		if (value0[0] != value1[0]) {
119 			printf("key:%llu value0:%llu != value1:%llu\n",
120 			       next_key, value0[0], value1[0]);
121 			return 0;
122 		}
123 	}
124 	return 1;
125 }
126 
127 static int map_equal(int lru_map, int expected)
128 {
129 	return map_subset(lru_map, expected) && map_subset(expected, lru_map);
130 }
131 
132 static int sched_next_online(int pid, int *next_to_try)
133 {
134 	cpu_set_t cpuset;
135 	int next = *next_to_try;
136 	int ret = -1;
137 
138 	while (next < nr_cpus) {
139 		CPU_ZERO(&cpuset);
140 		CPU_SET(next++, &cpuset);
141 		if (!sched_setaffinity(pid, sizeof(cpuset), &cpuset)) {
142 			ret = 0;
143 			break;
144 		}
145 	}
146 
147 	*next_to_try = next;
148 	return ret;
149 }
150 
151 /* Size of the LRU map is 2
152  * Add key=1 (+1 key)
153  * Add key=2 (+1 key)
154  * Lookup Key=1
155  * Add Key=3
156  *   => Key=2 will be removed by LRU
157  * Iterate map.  Only found key=1 and key=3
158  */
159 static void test_lru_sanity0(int map_type, int map_flags)
160 {
161 	unsigned long long key, value[nr_cpus];
162 	int lru_map_fd, expected_map_fd;
163 	int next_cpu = 0;
164 
165 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
166 	       map_flags);
167 
168 	assert(sched_next_online(0, &next_cpu) != -1);
169 
170 	if (map_flags & BPF_F_NO_COMMON_LRU)
171 		lru_map_fd = create_map(map_type, map_flags, 2 * nr_cpus);
172 	else
173 		lru_map_fd = create_map(map_type, map_flags, 2);
174 	assert(lru_map_fd != -1);
175 
176 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, 2);
177 	assert(expected_map_fd != -1);
178 
179 	value[0] = 1234;
180 
181 	/* insert key=1 element */
182 
183 	key = 1;
184 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
185 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
186 				    BPF_NOEXIST));
187 
188 	/* BPF_NOEXIST means: add new element if it doesn't exist */
189 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST) == -1
190 	       /* key=1 already exists */
191 	       && errno == EEXIST);
192 
193 	assert(bpf_map_update_elem(lru_map_fd, &key, value, -1) == -1 &&
194 	       errno == EINVAL);
195 
196 	/* insert key=2 element */
197 
198 	/* check that key=2 is not found */
199 	key = 2;
200 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
201 	       errno == ENOENT);
202 
203 	/* BPF_EXIST means: update existing element */
204 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_EXIST) == -1 &&
205 	       /* key=2 is not there */
206 	       errno == ENOENT);
207 
208 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
209 
210 	/* insert key=3 element */
211 
212 	/* check that key=3 is not found */
213 	key = 3;
214 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
215 	       errno == ENOENT);
216 
217 	/* check that key=1 can be found and mark the ref bit to
218 	 * stop LRU from removing key=1
219 	 */
220 	key = 1;
221 	assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
222 	assert(value[0] == 1234);
223 
224 	key = 3;
225 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
226 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
227 				    BPF_NOEXIST));
228 
229 	/* key=2 has been removed from the LRU */
230 	key = 2;
231 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
232 	       errno == ENOENT);
233 
234 	assert(map_equal(lru_map_fd, expected_map_fd));
235 
236 	close(expected_map_fd);
237 	close(lru_map_fd);
238 
239 	printf("Pass\n");
240 }
241 
242 /* Size of the LRU map is 1.5*tgt_free
243  * Insert 1 to tgt_free (+tgt_free keys)
244  * Lookup 1 to tgt_free/2
245  * Insert 1+tgt_free to 2*tgt_free (+tgt_free keys)
246  * => 1+tgt_free/2 to LOCALFREE_TARGET will be removed by LRU
247  */
248 static void test_lru_sanity1(int map_type, int map_flags, unsigned int tgt_free)
249 {
250 	unsigned long long key, end_key, value[nr_cpus];
251 	int lru_map_fd, expected_map_fd;
252 	unsigned int batch_size;
253 	unsigned int map_size;
254 	int next_cpu = 0;
255 
256 	if (map_flags & BPF_F_NO_COMMON_LRU)
257 		/* This test is only applicable to common LRU list */
258 		return;
259 
260 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
261 	       map_flags);
262 
263 	assert(sched_next_online(0, &next_cpu) != -1);
264 
265 	batch_size = tgt_free / 2;
266 	assert(batch_size * 2 == tgt_free);
267 
268 	map_size = tgt_free + batch_size;
269 	lru_map_fd = create_map(map_type, map_flags, map_size);
270 	assert(lru_map_fd != -1);
271 
272 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size);
273 	assert(expected_map_fd != -1);
274 
275 	value[0] = 1234;
276 
277 	/* Insert 1 to tgt_free (+tgt_free keys) */
278 	end_key = 1 + tgt_free;
279 	for (key = 1; key < end_key; key++)
280 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
281 					    BPF_NOEXIST));
282 
283 	/* Lookup 1 to tgt_free/2 */
284 	end_key = 1 + batch_size;
285 	for (key = 1; key < end_key; key++) {
286 		assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
287 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
288 					    BPF_NOEXIST));
289 	}
290 
291 	/* Insert 1+tgt_free to 2*tgt_free
292 	 * => 1+tgt_free/2 to LOCALFREE_TARGET will be
293 	 * removed by LRU
294 	 */
295 	key = 1 + tgt_free;
296 	end_key = key + tgt_free;
297 	for (; key < end_key; key++) {
298 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
299 					    BPF_NOEXIST));
300 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
301 					    BPF_NOEXIST));
302 	}
303 
304 	assert(map_equal(lru_map_fd, expected_map_fd));
305 
306 	close(expected_map_fd);
307 	close(lru_map_fd);
308 
309 	printf("Pass\n");
310 }
311 
312 /* Size of the LRU map 1.5 * tgt_free
313  * Insert 1 to tgt_free (+tgt_free keys)
314  * Update 1 to tgt_free/2
315  *   => The original 1 to tgt_free/2 will be removed due to
316  *      the LRU shrink process
317  * Re-insert 1 to tgt_free/2 again and do a lookup immeidately
318  * Insert 1+tgt_free to tgt_free*3/2
319  * Insert 1+tgt_free*3/2 to tgt_free*5/2
320  *   => Key 1+tgt_free to tgt_free*3/2
321  *      will be removed from LRU because it has never
322  *      been lookup and ref bit is not set
323  */
324 static void test_lru_sanity2(int map_type, int map_flags, unsigned int tgt_free)
325 {
326 	unsigned long long key, value[nr_cpus];
327 	unsigned long long end_key;
328 	int lru_map_fd, expected_map_fd;
329 	unsigned int batch_size;
330 	unsigned int map_size;
331 	int next_cpu = 0;
332 
333 	if (map_flags & BPF_F_NO_COMMON_LRU)
334 		/* This test is only applicable to common LRU list */
335 		return;
336 
337 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
338 	       map_flags);
339 
340 	assert(sched_next_online(0, &next_cpu) != -1);
341 
342 	batch_size = tgt_free / 2;
343 	assert(batch_size * 2 == tgt_free);
344 
345 	map_size = tgt_free + batch_size;
346 	lru_map_fd = create_map(map_type, map_flags, map_size);
347 	assert(lru_map_fd != -1);
348 
349 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size);
350 	assert(expected_map_fd != -1);
351 
352 	value[0] = 1234;
353 
354 	/* Insert 1 to tgt_free (+tgt_free keys) */
355 	end_key = 1 + tgt_free;
356 	for (key = 1; key < end_key; key++)
357 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
358 					    BPF_NOEXIST));
359 
360 	/* Any bpf_map_update_elem will require to acquire a new node
361 	 * from LRU first.
362 	 *
363 	 * The local list is running out of free nodes.
364 	 * It gets from the global LRU list which tries to
365 	 * shrink the inactive list to get tgt_free
366 	 * number of free nodes.
367 	 *
368 	 * Hence, the oldest key 1 to tgt_free/2
369 	 * are removed from the LRU list.
370 	 */
371 	key = 1;
372 	if (map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
373 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
374 					    BPF_NOEXIST));
375 		assert(!bpf_map_delete_elem(lru_map_fd, &key));
376 	} else {
377 		assert(bpf_map_update_elem(lru_map_fd, &key, value,
378 					   BPF_EXIST));
379 	}
380 
381 	/* Re-insert 1 to tgt_free/2 again and do a lookup
382 	 * immeidately.
383 	 */
384 	end_key = 1 + batch_size;
385 	value[0] = 4321;
386 	for (key = 1; key < end_key; key++) {
387 		assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
388 		       errno == ENOENT);
389 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
390 					    BPF_NOEXIST));
391 		assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
392 		assert(value[0] == 4321);
393 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
394 					    BPF_NOEXIST));
395 	}
396 
397 	value[0] = 1234;
398 
399 	/* Insert 1+tgt_free to tgt_free*3/2 */
400 	end_key = 1 + tgt_free + batch_size;
401 	for (key = 1 + tgt_free; key < end_key; key++)
402 		/* These newly added but not referenced keys will be
403 		 * gone during the next LRU shrink.
404 		 */
405 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
406 					    BPF_NOEXIST));
407 
408 	/* Insert 1+tgt_free*3/2 to  tgt_free*5/2 */
409 	end_key = key + tgt_free;
410 	for (; key < end_key; key++) {
411 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
412 					    BPF_NOEXIST));
413 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
414 					    BPF_NOEXIST));
415 	}
416 
417 	assert(map_equal(lru_map_fd, expected_map_fd));
418 
419 	close(expected_map_fd);
420 	close(lru_map_fd);
421 
422 	printf("Pass\n");
423 }
424 
425 /* Size of the LRU map is 2*tgt_free
426  * It is to test the active/inactive list rotation
427  * Insert 1 to 2*tgt_free (+2*tgt_free keys)
428  * Lookup key 1 to tgt_free*3/2
429  * Add 1+2*tgt_free to tgt_free*5/2 (+tgt_free/2 keys)
430  *  => key 1+tgt_free*3/2 to 2*tgt_free are removed from LRU
431  */
432 static void test_lru_sanity3(int map_type, int map_flags, unsigned int tgt_free)
433 {
434 	unsigned long long key, end_key, value[nr_cpus];
435 	int lru_map_fd, expected_map_fd;
436 	unsigned int batch_size;
437 	unsigned int map_size;
438 	int next_cpu = 0;
439 
440 	if (map_flags & BPF_F_NO_COMMON_LRU)
441 		/* This test is only applicable to common LRU list */
442 		return;
443 
444 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
445 	       map_flags);
446 
447 	assert(sched_next_online(0, &next_cpu) != -1);
448 
449 	batch_size = tgt_free / 2;
450 	assert(batch_size * 2 == tgt_free);
451 
452 	map_size = tgt_free * 2;
453 	lru_map_fd = create_map(map_type, map_flags, map_size);
454 	assert(lru_map_fd != -1);
455 
456 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size);
457 	assert(expected_map_fd != -1);
458 
459 	value[0] = 1234;
460 
461 	/* Insert 1 to 2*tgt_free (+2*tgt_free keys) */
462 	end_key = 1 + (2 * tgt_free);
463 	for (key = 1; key < end_key; key++)
464 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
465 					    BPF_NOEXIST));
466 
467 	/* Lookup key 1 to tgt_free*3/2 */
468 	end_key = tgt_free + batch_size;
469 	for (key = 1; key < end_key; key++) {
470 		assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
471 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
472 					    BPF_NOEXIST));
473 	}
474 
475 	/* Add 1+2*tgt_free to tgt_free*5/2
476 	 * (+tgt_free/2 keys)
477 	 */
478 	key = 2 * tgt_free + 1;
479 	end_key = key + batch_size;
480 	for (; key < end_key; key++) {
481 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
482 					    BPF_NOEXIST));
483 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
484 					    BPF_NOEXIST));
485 	}
486 
487 	assert(map_equal(lru_map_fd, expected_map_fd));
488 
489 	close(expected_map_fd);
490 	close(lru_map_fd);
491 
492 	printf("Pass\n");
493 }
494 
495 /* Test deletion */
496 static void test_lru_sanity4(int map_type, int map_flags, unsigned int tgt_free)
497 {
498 	int lru_map_fd, expected_map_fd;
499 	unsigned long long key, value[nr_cpus];
500 	unsigned long long end_key;
501 	int next_cpu = 0;
502 
503 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
504 	       map_flags);
505 
506 	assert(sched_next_online(0, &next_cpu) != -1);
507 
508 	if (map_flags & BPF_F_NO_COMMON_LRU)
509 		lru_map_fd = create_map(map_type, map_flags,
510 					3 * tgt_free * nr_cpus);
511 	else
512 		lru_map_fd = create_map(map_type, map_flags, 3 * tgt_free);
513 	assert(lru_map_fd != -1);
514 
515 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0,
516 				     3 * tgt_free);
517 	assert(expected_map_fd != -1);
518 
519 	value[0] = 1234;
520 
521 	for (key = 1; key <= 2 * tgt_free; key++)
522 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
523 					    BPF_NOEXIST));
524 
525 	key = 1;
526 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
527 
528 	for (key = 1; key <= tgt_free; key++) {
529 		assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
530 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
531 					    BPF_NOEXIST));
532 	}
533 
534 	for (; key <= 2 * tgt_free; key++) {
535 		assert(!bpf_map_delete_elem(lru_map_fd, &key));
536 		assert(bpf_map_delete_elem(lru_map_fd, &key));
537 	}
538 
539 	end_key = key + 2 * tgt_free;
540 	for (; key < end_key; key++) {
541 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
542 					    BPF_NOEXIST));
543 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
544 					    BPF_NOEXIST));
545 	}
546 
547 	assert(map_equal(lru_map_fd, expected_map_fd));
548 
549 	close(expected_map_fd);
550 	close(lru_map_fd);
551 
552 	printf("Pass\n");
553 }
554 
555 static void do_test_lru_sanity5(unsigned long long last_key, int map_fd)
556 {
557 	unsigned long long key, value[nr_cpus];
558 
559 	/* Ensure the last key inserted by previous CPU can be found */
560 	assert(!bpf_map_lookup_elem_with_ref_bit(map_fd, last_key, value));
561 	value[0] = 1234;
562 
563 	key = last_key + 1;
564 	assert(!bpf_map_update_elem(map_fd, &key, value, BPF_NOEXIST));
565 	assert(!bpf_map_lookup_elem_with_ref_bit(map_fd, key, value));
566 
567 	/* Cannot find the last key because it was removed by LRU */
568 	assert(bpf_map_lookup_elem(map_fd, &last_key, value) == -1 &&
569 	       errno == ENOENT);
570 }
571 
572 /* Test map with only one element */
573 static void test_lru_sanity5(int map_type, int map_flags)
574 {
575 	unsigned long long key, value[nr_cpus];
576 	int next_cpu = 0;
577 	int map_fd;
578 
579 	if (map_flags & BPF_F_NO_COMMON_LRU)
580 		return;
581 
582 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
583 	       map_flags);
584 
585 	map_fd = create_map(map_type, map_flags, 1);
586 	assert(map_fd != -1);
587 
588 	value[0] = 1234;
589 	key = 0;
590 	assert(!bpf_map_update_elem(map_fd, &key, value, BPF_NOEXIST));
591 
592 	while (sched_next_online(0, &next_cpu) != -1) {
593 		pid_t pid;
594 
595 		pid = fork();
596 		if (pid == 0) {
597 			do_test_lru_sanity5(key, map_fd);
598 			exit(0);
599 		} else if (pid == -1) {
600 			printf("couldn't spawn process to test key:%llu\n",
601 			       key);
602 			exit(1);
603 		} else {
604 			int status;
605 
606 			assert(waitpid(pid, &status, 0) == pid);
607 			assert(status == 0);
608 			key++;
609 		}
610 	}
611 
612 	close(map_fd);
613 	/* At least one key should be tested */
614 	assert(key > 0);
615 
616 	printf("Pass\n");
617 }
618 
619 /* Test list rotation for BPF_F_NO_COMMON_LRU map */
620 static void test_lru_sanity6(int map_type, int map_flags, int tgt_free)
621 {
622 	int lru_map_fd, expected_map_fd;
623 	unsigned long long key, value[nr_cpus];
624 	unsigned int map_size = tgt_free * 2;
625 	int next_cpu = 0;
626 
627 	if (!(map_flags & BPF_F_NO_COMMON_LRU))
628 		return;
629 
630 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
631 	       map_flags);
632 
633 	assert(sched_next_online(0, &next_cpu) != -1);
634 
635 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size);
636 	assert(expected_map_fd != -1);
637 
638 	lru_map_fd = create_map(map_type, map_flags, map_size * nr_cpus);
639 	assert(lru_map_fd != -1);
640 
641 	value[0] = 1234;
642 
643 	for (key = 1; key <= tgt_free; key++) {
644 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
645 					    BPF_NOEXIST));
646 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
647 					    BPF_NOEXIST));
648 	}
649 
650 	for (; key <= tgt_free * 2; key++) {
651 		unsigned long long stable_key;
652 
653 		/* Make ref bit sticky for key: [1, tgt_free] */
654 		for (stable_key = 1; stable_key <= tgt_free; stable_key++) {
655 			/* Mark the ref bit */
656 			assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd,
657 								 stable_key, value));
658 		}
659 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
660 					    BPF_NOEXIST));
661 	}
662 
663 	for (; key <= tgt_free * 3; key++) {
664 		assert(!bpf_map_update_elem(lru_map_fd, &key, value,
665 					    BPF_NOEXIST));
666 		assert(!bpf_map_update_elem(expected_map_fd, &key, value,
667 					    BPF_NOEXIST));
668 	}
669 
670 	assert(map_equal(lru_map_fd, expected_map_fd));
671 
672 	close(expected_map_fd);
673 	close(lru_map_fd);
674 
675 	printf("Pass\n");
676 }
677 
678 /* Size of the LRU map is 2
679  * Add key=1 (+1 key)
680  * Add key=2 (+1 key)
681  * Lookup Key=1 (datapath)
682  * Lookup Key=2 (syscall)
683  * Add Key=3
684  *   => Key=2 will be removed by LRU
685  * Iterate map.  Only found key=1 and key=3
686  */
687 static void test_lru_sanity7(int map_type, int map_flags)
688 {
689 	unsigned long long key, value[nr_cpus];
690 	int lru_map_fd, expected_map_fd;
691 	int next_cpu = 0;
692 
693 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
694 	       map_flags);
695 
696 	assert(sched_next_online(0, &next_cpu) != -1);
697 
698 	if (map_flags & BPF_F_NO_COMMON_LRU)
699 		lru_map_fd = create_map(map_type, map_flags, 2 * nr_cpus);
700 	else
701 		lru_map_fd = create_map(map_type, map_flags, 2);
702 	assert(lru_map_fd != -1);
703 
704 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, 2);
705 	assert(expected_map_fd != -1);
706 
707 	value[0] = 1234;
708 
709 	/* insert key=1 element */
710 
711 	key = 1;
712 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
713 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
714 				    BPF_NOEXIST));
715 
716 	/* BPF_NOEXIST means: add new element if it doesn't exist */
717 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST) == -1
718 	       /* key=1 already exists */
719 	       && errno == EEXIST);
720 
721 	/* insert key=2 element */
722 
723 	/* check that key=2 is not found */
724 	key = 2;
725 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
726 	       errno == ENOENT);
727 
728 	/* BPF_EXIST means: update existing element */
729 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_EXIST) == -1 &&
730 	       /* key=2 is not there */
731 	       errno == ENOENT);
732 
733 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
734 
735 	/* insert key=3 element */
736 
737 	/* check that key=3 is not found */
738 	key = 3;
739 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
740 	       errno == ENOENT);
741 
742 	/* check that key=1 can be found and mark the ref bit to
743 	 * stop LRU from removing key=1
744 	 */
745 	key = 1;
746 	assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
747 	assert(value[0] == 1234);
748 
749 	/* check that key=2 can be found and do _not_ mark ref bit.
750 	 * this will be evicted on next update.
751 	 */
752 	key = 2;
753 	assert(!bpf_map_lookup_elem(lru_map_fd, &key, value));
754 	assert(value[0] == 1234);
755 
756 	key = 3;
757 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
758 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
759 				    BPF_NOEXIST));
760 
761 	/* key=2 has been removed from the LRU */
762 	key = 2;
763 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
764 	       errno == ENOENT);
765 
766 	assert(map_equal(lru_map_fd, expected_map_fd));
767 
768 	close(expected_map_fd);
769 	close(lru_map_fd);
770 
771 	printf("Pass\n");
772 }
773 
774 /* Size of the LRU map is 2
775  * Add key=1 (+1 key)
776  * Add key=2 (+1 key)
777  * Lookup Key=1 (syscall)
778  * Lookup Key=2 (datapath)
779  * Add Key=3
780  *   => Key=1 will be removed by LRU
781  * Iterate map.  Only found key=2 and key=3
782  */
783 static void test_lru_sanity8(int map_type, int map_flags)
784 {
785 	unsigned long long key, value[nr_cpus];
786 	int lru_map_fd, expected_map_fd;
787 	int next_cpu = 0;
788 
789 	printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type,
790 	       map_flags);
791 
792 	assert(sched_next_online(0, &next_cpu) != -1);
793 
794 	if (map_flags & BPF_F_NO_COMMON_LRU)
795 		lru_map_fd = create_map(map_type, map_flags, 2 * nr_cpus);
796 	else
797 		lru_map_fd = create_map(map_type, map_flags, 2);
798 	assert(lru_map_fd != -1);
799 
800 	expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, 2);
801 	assert(expected_map_fd != -1);
802 
803 	value[0] = 1234;
804 
805 	/* insert key=1 element */
806 
807 	key = 1;
808 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
809 
810 	/* BPF_NOEXIST means: add new element if it doesn't exist */
811 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST) == -1
812 	       /* key=1 already exists */
813 	       && errno == EEXIST);
814 
815 	/* insert key=2 element */
816 
817 	/* check that key=2 is not found */
818 	key = 2;
819 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
820 	       errno == ENOENT);
821 
822 	/* BPF_EXIST means: update existing element */
823 	assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_EXIST) == -1 &&
824 	       /* key=2 is not there */
825 	       errno == ENOENT);
826 
827 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
828 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
829 				    BPF_NOEXIST));
830 
831 	/* insert key=3 element */
832 
833 	/* check that key=3 is not found */
834 	key = 3;
835 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
836 	       errno == ENOENT);
837 
838 	/* check that key=1 can be found and do _not_ mark ref bit.
839 	 * this will be evicted on next update.
840 	 */
841 	key = 1;
842 	assert(!bpf_map_lookup_elem(lru_map_fd, &key, value));
843 	assert(value[0] == 1234);
844 
845 	/* check that key=2 can be found and mark the ref bit to
846 	 * stop LRU from removing key=2
847 	 */
848 	key = 2;
849 	assert(!bpf_map_lookup_elem_with_ref_bit(lru_map_fd, key, value));
850 	assert(value[0] == 1234);
851 
852 	key = 3;
853 	assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST));
854 	assert(!bpf_map_update_elem(expected_map_fd, &key, value,
855 				    BPF_NOEXIST));
856 
857 	/* key=1 has been removed from the LRU */
858 	key = 1;
859 	assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 &&
860 	       errno == ENOENT);
861 
862 	assert(map_equal(lru_map_fd, expected_map_fd));
863 
864 	close(expected_map_fd);
865 	close(lru_map_fd);
866 
867 	printf("Pass\n");
868 }
869 
870 int main(int argc, char **argv)
871 {
872 	int map_types[] = {BPF_MAP_TYPE_LRU_HASH,
873 			     BPF_MAP_TYPE_LRU_PERCPU_HASH};
874 	int map_flags[] = {0, BPF_F_NO_COMMON_LRU};
875 	int t, f;
876 
877 	setbuf(stdout, NULL);
878 
879 	nr_cpus = bpf_num_possible_cpus();
880 	assert(nr_cpus != -1);
881 	printf("nr_cpus:%d\n\n", nr_cpus);
882 
883 	for (f = 0; f < sizeof(map_flags) / sizeof(*map_flags); f++) {
884 		unsigned int tgt_free = (map_flags[f] & BPF_F_NO_COMMON_LRU) ?
885 			PERCPU_FREE_TARGET : LOCAL_FREE_TARGET;
886 
887 		for (t = 0; t < sizeof(map_types) / sizeof(*map_types); t++) {
888 			test_lru_sanity0(map_types[t], map_flags[f]);
889 			test_lru_sanity1(map_types[t], map_flags[f], tgt_free);
890 			test_lru_sanity2(map_types[t], map_flags[f], tgt_free);
891 			test_lru_sanity3(map_types[t], map_flags[f], tgt_free);
892 			test_lru_sanity4(map_types[t], map_flags[f], tgt_free);
893 			test_lru_sanity5(map_types[t], map_flags[f]);
894 			test_lru_sanity6(map_types[t], map_flags[f], tgt_free);
895 			test_lru_sanity7(map_types[t], map_flags[f]);
896 			test_lru_sanity8(map_types[t], map_flags[f]);
897 
898 			printf("\n");
899 		}
900 	}
901 
902 	return 0;
903 }
904