bpf/prog_tests/ringbuf_multi.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 #define _GNU_SOURCE
0003 #include <test_progs.h>
0004 #include <sys/epoll.h>
0005 #include "test_ringbuf_multi.skel.h"
0006
0007 static int duration = 0;
0008
0009 struct sample {
0010     int pid;
0011     int seq;
0012     long value;
0013     char comm[16];
0014 };
0015
0016 static int process_sample(void *ctx, void *data, size_t len)
0017 {
0018     int ring = (unsigned long)ctx;
0019     struct sample *s = data;
0020
0021     switch (s->seq) {
0022     case 0:
0023         CHECK(ring != 1, "sample1_ring", "exp %d, got %d\n", 1, ring);
0024         CHECK(s->value != 333, "sample1_value", "exp %ld, got %ld\n",
0025               333L, s->value);
0026         break;
0027     case 1:
0028         CHECK(ring != 2, "sample2_ring", "exp %d, got %d\n", 2, ring);
0029         CHECK(s->value != 777, "sample2_value", "exp %ld, got %ld\n",
0030               777L, s->value);
0031         break;
0032     default:
0033         CHECK(true, "extra_sample", "unexpected sample seq %d, val %ld\n",
0034               s->seq, s->value);
0035         return -1;
0036     }
0037
0038     return 0;
0039 }
0040
0041 void test_ringbuf_multi(void)
0042 {
0043     struct test_ringbuf_multi *skel;
0044     struct ring_buffer *ringbuf = NULL;
0045     int err;
0046     int page_size = getpagesize();
0047     int proto_fd = -1;
0048
0049     skel = test_ringbuf_multi__open();
0050     if (CHECK(!skel, "skel_open", "skeleton open failed\n"))
0051         return;
0052
0053     /* validate ringbuf size adjustment logic */
0054     ASSERT_EQ(bpf_map__max_entries(skel->maps.ringbuf1), page_size, "rb1_size_before");
0055     ASSERT_OK(bpf_map__set_max_entries(skel->maps.ringbuf1, page_size + 1), "rb1_resize");
0056     ASSERT_EQ(bpf_map__max_entries(skel->maps.ringbuf1), 2 * page_size, "rb1_size_after");
0057     ASSERT_OK(bpf_map__set_max_entries(skel->maps.ringbuf1, page_size), "rb1_reset");
0058     ASSERT_EQ(bpf_map__max_entries(skel->maps.ringbuf1), page_size, "rb1_size_final");
0059
0060     proto_fd = bpf_map_create(BPF_MAP_TYPE_RINGBUF, NULL, 0, 0, page_size, NULL);
0061     if (CHECK(proto_fd < 0, "bpf_map_create", "bpf_map_create failed\n"))
0062         goto cleanup;
0063
0064     err = bpf_map__set_inner_map_fd(skel->maps.ringbuf_hash, proto_fd);
0065     if (CHECK(err != 0, "bpf_map__set_inner_map_fd", "bpf_map__set_inner_map_fd failed\n"))
0066         goto cleanup;
0067
0068     err = test_ringbuf_multi__load(skel);
0069     if (CHECK(err != 0, "skel_load", "skeleton load failed\n"))
0070         goto cleanup;
0071
0072     close(proto_fd);
0073     proto_fd = -1;
0074
0075     /* make sure we can't resize ringbuf after object load */
0076     if (!ASSERT_ERR(bpf_map__set_max_entries(skel->maps.ringbuf1, 3 * page_size), "rb1_resize_after_load"))
0077         goto cleanup;
0078
0079     /* only trigger BPF program for current process */
0080     skel->bss->pid = getpid();
0081
0082     ringbuf = ring_buffer__new(bpf_map__fd(skel->maps.ringbuf1),
0083                    process_sample, (void *)(long)1, NULL);
0084     if (CHECK(!ringbuf, "ringbuf_create", "failed to create ringbuf\n"))
0085         goto cleanup;
0086
0087     err = ring_buffer__add(ringbuf, bpf_map__fd(skel->maps.ringbuf2),
0088                   process_sample, (void *)(long)2);
0089     if (CHECK(err, "ringbuf_add", "failed to add another ring\n"))
0090         goto cleanup;
0091
0092     err = test_ringbuf_multi__attach(skel);
0093     if (CHECK(err, "skel_attach", "skeleton attachment failed: %d\n", err))
0094         goto cleanup;
0095
0096     /* trigger few samples, some will be skipped */
0097     skel->bss->target_ring = 0;
0098     skel->bss->value = 333;
0099     syscall(__NR_getpgid);
0100
0101     /* skipped, no ringbuf in slot 1 */
0102     skel->bss->target_ring = 1;
0103     skel->bss->value = 555;
0104     syscall(__NR_getpgid);
0105
0106     skel->bss->target_ring = 2;
0107     skel->bss->value = 777;
0108     syscall(__NR_getpgid);
0109
0110     /* poll for samples, should get 2 ringbufs back */
0111     err = ring_buffer__poll(ringbuf, -1);
0112     if (CHECK(err != 2, "poll_res", "expected 2 records, got %d\n", err))
0113         goto cleanup;
0114
0115     /* expect extra polling to return nothing */
0116     err = ring_buffer__poll(ringbuf, 0);
0117     if (CHECK(err < 0, "extra_samples", "poll result: %d\n", err))
0118         goto cleanup;
0119
0120     CHECK(skel->bss->dropped != 0, "err_dropped", "exp %ld, got %ld\n",
0121           0L, skel->bss->dropped);
0122     CHECK(skel->bss->skipped != 1, "err_skipped", "exp %ld, got %ld\n",
0123           1L, skel->bss->skipped);
0124     CHECK(skel->bss->total != 2, "err_total", "exp %ld, got %ld\n",
0125           2L, skel->bss->total);
0126
0127 cleanup:
0128     if (proto_fd >= 0)
0129         close(proto_fd);
0130     ring_buffer__free(ringbuf);
0131     test_ringbuf_multi__destroy(skel);
0132 }