tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c

   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 }