1 // SPDX-License-Identifier: GPL-2.0
2 
3 #define _GNU_SOURCE
4 #include <linux/bpf.h>
5 #include <stdio.h>
6 #include <stdbool.h>
7 #include <unistd.h>
8 #include <errno.h>
9 #include <stdlib.h>
10 #include <string.h>
11 #include <pthread.h>
12 
13 #include <bpf/bpf.h>
14 #include <bpf/libbpf.h>
15 
16 #include <test_maps.h>
17 
18 struct test_lpm_key {
19 	__u32 prefix;
20 	__u32 data;
21 };
22 
23 struct get_next_key_ctx {
24 	struct test_lpm_key key;
25 	bool start;
26 	bool stop;
27 	int map_fd;
28 	int loop;
29 };
30 
get_next_key_fn(void * arg)31 static void *get_next_key_fn(void *arg)
32 {
33 	struct get_next_key_ctx *ctx = arg;
34 	struct test_lpm_key next_key;
35 	int i = 0;
36 
37 	while (!ctx->start)
38 		usleep(1);
39 
40 	while (!ctx->stop && i++ < ctx->loop)
41 		bpf_map_get_next_key(ctx->map_fd, &ctx->key, &next_key);
42 
43 	return NULL;
44 }
45 
abort_get_next_key(struct get_next_key_ctx * ctx,pthread_t * tids,unsigned int nr)46 static void abort_get_next_key(struct get_next_key_ctx *ctx, pthread_t *tids,
47 			       unsigned int nr)
48 {
49 	unsigned int i;
50 
51 	ctx->stop = true;
52 	ctx->start = true;
53 	for (i = 0; i < nr; i++)
54 		pthread_join(tids[i], NULL);
55 }
56 
57 /* This test aims to prevent regression of future. As long as the kernel does
58  * not panic, it is considered as success.
59  */
test_lpm_trie_map_get_next_key(void)60 void test_lpm_trie_map_get_next_key(void)
61 {
62 #define MAX_NR_THREADS 8
63 	LIBBPF_OPTS(bpf_map_create_opts, create_opts,
64 		    .map_flags = BPF_F_NO_PREALLOC);
65 	struct test_lpm_key key = {};
66 	__u32 val = 0;
67 	int map_fd;
68 	const __u32 max_prefixlen = 8 * (sizeof(key) - sizeof(key.prefix));
69 	const __u32 max_entries = max_prefixlen + 1;
70 	unsigned int i, nr = MAX_NR_THREADS, loop = 65536;
71 	pthread_t tids[MAX_NR_THREADS];
72 	struct get_next_key_ctx ctx;
73 	int err;
74 
75 	map_fd = bpf_map_create(BPF_MAP_TYPE_LPM_TRIE, "lpm_trie_map",
76 				sizeof(struct test_lpm_key), sizeof(__u32),
77 				max_entries, &create_opts);
78 	CHECK(map_fd == -1, "bpf_map_create()", "error:%s\n",
79 	      strerror(errno));
80 
81 	for (i = 0; i <= max_prefixlen; i++) {
82 		key.prefix = i;
83 		err = bpf_map_update_elem(map_fd, &key, &val, BPF_ANY);
84 		CHECK(err, "bpf_map_update_elem()", "error:%s\n",
85 		      strerror(errno));
86 	}
87 
88 	ctx.start = false;
89 	ctx.stop = false;
90 	ctx.map_fd = map_fd;
91 	ctx.loop = loop;
92 	memcpy(&ctx.key, &key, sizeof(key));
93 
94 	for (i = 0; i < nr; i++) {
95 		err = pthread_create(&tids[i], NULL, get_next_key_fn, &ctx);
96 		if (err) {
97 			abort_get_next_key(&ctx, tids, i);
98 			CHECK(err, "pthread_create", "error %d\n", err);
99 		}
100 	}
101 
102 	ctx.start = true;
103 	for (i = 0; i < nr; i++)
104 		pthread_join(tids[i], NULL);
105 
106 	printf("%s:PASS\n", __func__);
107 
108 	close(map_fd);
109 }
110