xref: /linux/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c (revision a6bdc082ad1c91d389a6ba0c7a1945818f732114)
1 // SPDX-License-Identifier: GPL-2.0
2 #define _GNU_SOURCE
3 #include <test_progs.h>
4 #include <sys/epoll.h>
5 #include "test_ringbuf_multi.skel.h"
6 
7 static int duration = 0;
8 
9 struct sample {
10 	int pid;
11 	int seq;
12 	long value;
13 	char comm[16];
14 };
15 
16 static int process_sample(void *ctx, void *data, size_t len)
17 {
18 	int ring = (unsigned long)ctx;
19 	struct sample *s = data;
20 
21 	switch (s->seq) {
22 	case 0:
23 		CHECK(ring != 1, "sample1_ring", "exp %d, got %d\n", 1, ring);
24 		CHECK(s->value != 333, "sample1_value", "exp %ld, got %ld\n",
25 		      333L, s->value);
26 		break;
27 	case 1:
28 		CHECK(ring != 2, "sample2_ring", "exp %d, got %d\n", 2, ring);
29 		CHECK(s->value != 777, "sample2_value", "exp %ld, got %ld\n",
30 		      777L, s->value);
31 		break;
32 	default:
33 		CHECK(true, "extra_sample", "unexpected sample seq %d, val %ld\n",
34 		      s->seq, s->value);
35 		return -1;
36 	}
37 
38 	return 0;
39 }
40 
41 void test_ringbuf_multi(void)
42 {
43 	struct test_ringbuf_multi *skel;
44 	struct ring_buffer *ringbuf = NULL;
45 	struct ring *ring_old;
46 	struct ring *ring;
47 	int err;
48 	int page_size = getpagesize();
49 	int proto_fd = -1;
50 
51 	skel = test_ringbuf_multi__open();
52 	if (CHECK(!skel, "skel_open", "skeleton open failed\n"))
53 		return;
54 
55 	/* validate ringbuf size adjustment logic */
56 	ASSERT_EQ(bpf_map__max_entries(skel->maps.ringbuf1), page_size, "rb1_size_before");
57 	ASSERT_OK(bpf_map__set_max_entries(skel->maps.ringbuf1, page_size + 1), "rb1_resize");
58 	ASSERT_EQ(bpf_map__max_entries(skel->maps.ringbuf1), 2 * page_size, "rb1_size_after");
59 	ASSERT_OK(bpf_map__set_max_entries(skel->maps.ringbuf1, page_size), "rb1_reset");
60 	ASSERT_EQ(bpf_map__max_entries(skel->maps.ringbuf1), page_size, "rb1_size_final");
61 
62 	proto_fd = bpf_map_create(BPF_MAP_TYPE_RINGBUF, NULL, 0, 0, page_size, NULL);
63 	if (CHECK(proto_fd < 0, "bpf_map_create", "bpf_map_create failed\n"))
64 		goto cleanup;
65 
66 	err = bpf_map__set_inner_map_fd(skel->maps.ringbuf_hash, proto_fd);
67 	if (CHECK(err != 0, "bpf_map__set_inner_map_fd", "bpf_map__set_inner_map_fd failed\n"))
68 		goto cleanup;
69 
70 	err = test_ringbuf_multi__load(skel);
71 	if (CHECK(err != 0, "skel_load", "skeleton load failed\n"))
72 		goto cleanup;
73 
74 	close(proto_fd);
75 	proto_fd = -1;
76 
77 	/* make sure we can't resize ringbuf after object load */
78 	if (!ASSERT_ERR(bpf_map__set_max_entries(skel->maps.ringbuf1, 3 * page_size), "rb1_resize_after_load"))
79 		goto cleanup;
80 
81 	/* only trigger BPF program for current process */
82 	skel->bss->pid = getpid();
83 
84 	ringbuf = ring_buffer__new(bpf_map__fd(skel->maps.ringbuf1),
85 				   process_sample, (void *)(long)1, NULL);
86 	if (CHECK(!ringbuf, "ringbuf_create", "failed to create ringbuf\n"))
87 		goto cleanup;
88 
89 	/* verify ring_buffer__ring returns expected results */
90 	ring = ring_buffer__ring(ringbuf, 0);
91 	if (!ASSERT_OK_PTR(ring, "ring_buffer__ring_idx_0"))
92 		goto cleanup;
93 	ring_old = ring;
94 	ring = ring_buffer__ring(ringbuf, 1);
95 	ASSERT_ERR_PTR(ring, "ring_buffer__ring_idx_1");
96 
97 	err = ring_buffer__add(ringbuf, bpf_map__fd(skel->maps.ringbuf2),
98 			      process_sample, (void *)(long)2);
99 	if (CHECK(err, "ringbuf_add", "failed to add another ring\n"))
100 		goto cleanup;
101 
102 	/* verify adding a new ring didn't invalidate our older pointer */
103 	ring = ring_buffer__ring(ringbuf, 0);
104 	if (!ASSERT_EQ(ring, ring_old, "ring_buffer__ring_again"))
105 		goto cleanup;
106 
107 	err = test_ringbuf_multi__attach(skel);
108 	if (CHECK(err, "skel_attach", "skeleton attachment failed: %d\n", err))
109 		goto cleanup;
110 
111 	/* trigger few samples, some will be skipped */
112 	skel->bss->target_ring = 0;
113 	skel->bss->value = 333;
114 	syscall(__NR_getpgid);
115 
116 	/* skipped, no ringbuf in slot 1 */
117 	skel->bss->target_ring = 1;
118 	skel->bss->value = 555;
119 	syscall(__NR_getpgid);
120 
121 	skel->bss->target_ring = 2;
122 	skel->bss->value = 777;
123 	syscall(__NR_getpgid);
124 
125 	/* poll for samples, should get 2 ringbufs back */
126 	err = ring_buffer__poll(ringbuf, -1);
127 	if (CHECK(err != 2, "poll_res", "expected 2 records, got %d\n", err))
128 		goto cleanup;
129 
130 	/* expect extra polling to return nothing */
131 	err = ring_buffer__poll(ringbuf, 0);
132 	if (CHECK(err < 0, "extra_samples", "poll result: %d\n", err))
133 		goto cleanup;
134 
135 	CHECK(skel->bss->dropped != 0, "err_dropped", "exp %ld, got %ld\n",
136 	      0L, skel->bss->dropped);
137 	CHECK(skel->bss->skipped != 1, "err_skipped", "exp %ld, got %ld\n",
138 	      1L, skel->bss->skipped);
139 	CHECK(skel->bss->total != 2, "err_total", "exp %ld, got %ld\n",
140 	      2L, skel->bss->total);
141 
142 cleanup:
143 	if (proto_fd >= 0)
144 		close(proto_fd);
145 	ring_buffer__free(ringbuf);
146 	test_ringbuf_multi__destroy(skel);
147 }
148