1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include <linux/unistd.h> |
3 | #include <linux/bpf.h> |
4 | |
5 | #include <stdlib.h> |
6 | #include <stdio.h> |
7 | #include <unistd.h> |
8 | #include <string.h> |
9 | #include <errno.h> |
10 | #include <arpa/inet.h> |
11 | |
12 | #include <bpf/bpf.h> |
13 | #include "bpf_util.h" |
14 | |
15 | #define MAX_INDEX 64 |
16 | #define MAX_STARS 38 |
17 | |
18 | static void stars(char *str, long val, long max, int width) |
19 | { |
20 | int i; |
21 | |
22 | for (i = 0; i < (width * val / max) - 1 && i < width - 1; i++) |
23 | str[i] = '*'; |
24 | if (val > max) |
25 | str[i - 1] = '+'; |
26 | str[i] = '\0'; |
27 | } |
28 | |
29 | int main(int argc, char **argv) |
30 | { |
31 | unsigned int nr_cpus = bpf_num_possible_cpus(); |
32 | const char *map_filename = "/sys/fs/bpf/tc/globals/lwt_len_hist_map" ; |
33 | uint64_t values[nr_cpus], sum, max_value = 0, data[MAX_INDEX] = {}; |
34 | uint64_t key = 0, next_key, max_key = 0; |
35 | char starstr[MAX_STARS]; |
36 | int i, map_fd; |
37 | |
38 | map_fd = bpf_obj_get(map_filename); |
39 | if (map_fd < 0) { |
40 | fprintf(stderr, format: "bpf_obj_get(%s): %s(%d)\n" , |
41 | map_filename, strerror(errno), errno); |
42 | return -1; |
43 | } |
44 | |
45 | while (bpf_map_get_next_key(map_fd, &key, &next_key) == 0) { |
46 | if (next_key >= MAX_INDEX) { |
47 | fprintf(stderr, format: "Key %lu out of bounds\n" , next_key); |
48 | continue; |
49 | } |
50 | |
51 | bpf_map_lookup_elem(map_fd, &next_key, values); |
52 | |
53 | sum = 0; |
54 | for (i = 0; i < nr_cpus; i++) |
55 | sum += values[i]; |
56 | |
57 | data[next_key] = sum; |
58 | if (sum && next_key > max_key) |
59 | max_key = next_key; |
60 | |
61 | if (sum > max_value) |
62 | max_value = sum; |
63 | |
64 | key = next_key; |
65 | } |
66 | |
67 | for (i = 1; i <= max_key + 1; i++) { |
68 | stars(str: starstr, val: data[i - 1], max: max_value, MAX_STARS); |
69 | printf(format: "%8ld -> %-8ld : %-8ld |%-*s|\n" , |
70 | (1l << i) >> 1, (1l << i) - 1, data[i - 1], |
71 | MAX_STARS, starstr); |
72 | } |
73 | |
74 | close(fd: map_fd); |
75 | |
76 | return 0; |
77 | } |
78 | |