tools/testing/selftests/bpf/test_netcnt.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include <errno.h>
   6 #include <assert.h>
   7 #include <sys/sysinfo.h>
   8 #include <sys/time.h>
   9
  10 #include <linux/bpf.h>
  11 #include <bpf/bpf.h>
  12 #include <bpf/libbpf.h>
  13
  14 #include "cgroup_helpers.h"
  15 #include "bpf_rlimit.h"
  16 #include "netcnt_common.h"
  17
  18 #define BPF_PROG "./netcnt_prog.o"
  19 #define TEST_CGROUP "/test-network-counters/"
  20
  21 static int bpf_find_map(const char *test, struct bpf_object *obj,
  22                         const char *name)
  23 {
  24         struct bpf_map *map;
  25
  26         map = bpf_object__find_map_by_name(obj, name);
  27         if (!map) {
  28                 printf("%s:FAIL:map '%s' not found\n", test, name);
  29                 return -1;
  30         }
  31         return bpf_map__fd(map);
  32 }
  33
  34 int main(int argc, char **argv)
  35 {
  36         struct percpu_net_cnt *percpu_netcnt;
  37         struct bpf_cgroup_storage_key key;
  38         int map_fd, percpu_map_fd;
  39         int error = EXIT_FAILURE;
  40         struct net_cnt netcnt;
  41         struct bpf_object *obj;
  42         int prog_fd, cgroup_fd;
  43         unsigned long packets;
  44         unsigned long bytes;
  45         int cpu, nproc;
  46         __u32 prog_cnt;
  47
  48         nproc = get_nprocs_conf();
  49         percpu_netcnt = malloc(sizeof(*percpu_netcnt) * nproc);
  50         if (!percpu_netcnt) {
  51                 printf("Not enough memory for per-cpu area (%d cpus)\n", nproc);
  52                 goto err;
  53         }
  54
  55         if (bpf_prog_load(BPF_PROG, BPF_PROG_TYPE_CGROUP_SKB,
  56                           &obj, &prog_fd)) {
  57                 printf("Failed to load bpf program\n");
  58                 goto out;
  59         }
  60
  61         cgroup_fd = cgroup_setup_and_join(TEST_CGROUP);
  62         if (cgroup_fd < 0)
  63                 goto err;
  64
  65         /* Attach bpf program */
  66         if (bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_INET_EGRESS, 0)) {
  67                 printf("Failed to attach bpf program");
  68                 goto err;
  69         }
  70
  71         if (system("which ping6 &>/dev/null") == 0)
  72                 assert(!system("ping6 ::1 -c 10000 -f -q > /dev/null"));
  73         else
  74                 assert(!system("ping -6 ::1 -c 10000 -f -q > /dev/null"));
  75
  76         if (bpf_prog_query(cgroup_fd, BPF_CGROUP_INET_EGRESS, 0, NULL, NULL,
  77                            &prog_cnt)) {
  78                 printf("Failed to query attached programs");
  79                 goto err;
  80         }
  81
  82         map_fd = bpf_find_map(__func__, obj, "netcnt");
  83         if (map_fd < 0) {
  84                 printf("Failed to find bpf map with net counters");
  85                 goto err;
  86         }
  87
  88         percpu_map_fd = bpf_find_map(__func__, obj, "percpu_netcnt");
  89         if (percpu_map_fd < 0) {
  90                 printf("Failed to find bpf map with percpu net counters");
  91                 goto err;
  92         }
  93
  94         if (bpf_map_get_next_key(map_fd, NULL, &key)) {
  95                 printf("Failed to get key in cgroup storage\n");
  96                 goto err;
  97         }
  98
  99         if (bpf_map_lookup_elem(map_fd, &key, &netcnt)) {
 100                 printf("Failed to lookup cgroup storage\n");
 101                 goto err;
 102         }
 103
 104         if (bpf_map_lookup_elem(percpu_map_fd, &key, &percpu_netcnt[0])) {
 105                 printf("Failed to lookup percpu cgroup storage\n");
 106                 goto err;
 107         }
 108
 109         /* Some packets can be still in per-cpu cache, but not more than
 110          * MAX_PERCPU_PACKETS.
 111          */
 112         packets = netcnt.packets;
 113         bytes = netcnt.bytes;
 114         for (cpu = 0; cpu < nproc; cpu++) {
 115                 if (percpu_netcnt[cpu].packets > MAX_PERCPU_PACKETS) {
 116                         printf("Unexpected percpu value: %llu\n",
 117                                percpu_netcnt[cpu].packets);
 118                         goto err;
 119                 }
 120
 121                 packets += percpu_netcnt[cpu].packets;
 122                 bytes += percpu_netcnt[cpu].bytes;
 123         }
 124
 125         /* No packets should be lost */
 126         if (packets != 10000) {
 127                 printf("Unexpected packet count: %lu\n", packets);
 128                 goto err;
 129         }
 130
 131         /* Let's check that bytes counter matches the number of packets
 132          * multiplied by the size of ipv6 ICMP packet.
 133          */
 134         if (bytes != packets * 104) {
 135                 printf("Unexpected bytes count: %lu\n", bytes);
 136                 goto err;
 137         }
 138
 139         error = 0;
 140         printf("test_netcnt:PASS\n");
 141
 142 err:
 143         cleanup_cgroup_environment();
 144         free(percpu_netcnt);
 145
 146 out:
 147         return error;
 148 }