1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com
3*4882a593Smuzhiyun * Copyright (c) 2015 BMW Car IT GmbH
4*4882a593Smuzhiyun */
5*4882a593Smuzhiyun #include <stdio.h>
6*4882a593Smuzhiyun #include <unistd.h>
7*4882a593Smuzhiyun #include <stdlib.h>
8*4882a593Smuzhiyun #include <signal.h>
9*4882a593Smuzhiyun #include <bpf/libbpf.h>
10*4882a593Smuzhiyun #include <bpf/bpf.h>
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun #define MAX_ENTRIES 20
13*4882a593Smuzhiyun #define MAX_CPU 4
14*4882a593Smuzhiyun #define MAX_STARS 40
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun struct cpu_hist {
17*4882a593Smuzhiyun long data[MAX_ENTRIES];
18*4882a593Smuzhiyun long max;
19*4882a593Smuzhiyun };
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun static struct cpu_hist cpu_hist[MAX_CPU];
22*4882a593Smuzhiyun
stars(char * str,long val,long max,int width)23*4882a593Smuzhiyun static void stars(char *str, long val, long max, int width)
24*4882a593Smuzhiyun {
25*4882a593Smuzhiyun int i;
26*4882a593Smuzhiyun
27*4882a593Smuzhiyun for (i = 0; i < (width * val / max) - 1 && i < width - 1; i++)
28*4882a593Smuzhiyun str[i] = '*';
29*4882a593Smuzhiyun if (val > max)
30*4882a593Smuzhiyun str[i - 1] = '+';
31*4882a593Smuzhiyun str[i] = '\0';
32*4882a593Smuzhiyun }
33*4882a593Smuzhiyun
print_hist(void)34*4882a593Smuzhiyun static void print_hist(void)
35*4882a593Smuzhiyun {
36*4882a593Smuzhiyun char starstr[MAX_STARS];
37*4882a593Smuzhiyun struct cpu_hist *hist;
38*4882a593Smuzhiyun int i, j;
39*4882a593Smuzhiyun
40*4882a593Smuzhiyun /* clear screen */
41*4882a593Smuzhiyun printf("\033[2J");
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun for (j = 0; j < MAX_CPU; j++) {
44*4882a593Smuzhiyun hist = &cpu_hist[j];
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun /* ignore CPUs without data (maybe offline?) */
47*4882a593Smuzhiyun if (hist->max == 0)
48*4882a593Smuzhiyun continue;
49*4882a593Smuzhiyun
50*4882a593Smuzhiyun printf("CPU %d\n", j);
51*4882a593Smuzhiyun printf(" latency : count distribution\n");
52*4882a593Smuzhiyun for (i = 1; i <= MAX_ENTRIES; i++) {
53*4882a593Smuzhiyun stars(starstr, hist->data[i - 1], hist->max, MAX_STARS);
54*4882a593Smuzhiyun printf("%8ld -> %-8ld : %-8ld |%-*s|\n",
55*4882a593Smuzhiyun (1l << i) >> 1, (1l << i) - 1,
56*4882a593Smuzhiyun hist->data[i - 1], MAX_STARS, starstr);
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun }
59*4882a593Smuzhiyun }
60*4882a593Smuzhiyun
get_data(int fd)61*4882a593Smuzhiyun static void get_data(int fd)
62*4882a593Smuzhiyun {
63*4882a593Smuzhiyun long key, value;
64*4882a593Smuzhiyun int c, i;
65*4882a593Smuzhiyun
66*4882a593Smuzhiyun for (i = 0; i < MAX_CPU; i++)
67*4882a593Smuzhiyun cpu_hist[i].max = 0;
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun for (c = 0; c < MAX_CPU; c++) {
70*4882a593Smuzhiyun for (i = 0; i < MAX_ENTRIES; i++) {
71*4882a593Smuzhiyun key = c * MAX_ENTRIES + i;
72*4882a593Smuzhiyun bpf_map_lookup_elem(fd, &key, &value);
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun cpu_hist[c].data[i] = value;
75*4882a593Smuzhiyun if (value > cpu_hist[c].max)
76*4882a593Smuzhiyun cpu_hist[c].max = value;
77*4882a593Smuzhiyun }
78*4882a593Smuzhiyun }
79*4882a593Smuzhiyun }
80*4882a593Smuzhiyun
main(int argc,char ** argv)81*4882a593Smuzhiyun int main(int argc, char **argv)
82*4882a593Smuzhiyun {
83*4882a593Smuzhiyun struct bpf_link *links[2];
84*4882a593Smuzhiyun struct bpf_program *prog;
85*4882a593Smuzhiyun struct bpf_object *obj;
86*4882a593Smuzhiyun char filename[256];
87*4882a593Smuzhiyun int map_fd, i = 0;
88*4882a593Smuzhiyun
89*4882a593Smuzhiyun snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
90*4882a593Smuzhiyun obj = bpf_object__open_file(filename, NULL);
91*4882a593Smuzhiyun if (libbpf_get_error(obj)) {
92*4882a593Smuzhiyun fprintf(stderr, "ERROR: opening BPF object file failed\n");
93*4882a593Smuzhiyun return 0;
94*4882a593Smuzhiyun }
95*4882a593Smuzhiyun
96*4882a593Smuzhiyun /* load BPF program */
97*4882a593Smuzhiyun if (bpf_object__load(obj)) {
98*4882a593Smuzhiyun fprintf(stderr, "ERROR: loading BPF object file failed\n");
99*4882a593Smuzhiyun goto cleanup;
100*4882a593Smuzhiyun }
101*4882a593Smuzhiyun
102*4882a593Smuzhiyun map_fd = bpf_object__find_map_fd_by_name(obj, "my_lat");
103*4882a593Smuzhiyun if (map_fd < 0) {
104*4882a593Smuzhiyun fprintf(stderr, "ERROR: finding a map in obj file failed\n");
105*4882a593Smuzhiyun goto cleanup;
106*4882a593Smuzhiyun }
107*4882a593Smuzhiyun
108*4882a593Smuzhiyun bpf_object__for_each_program(prog, obj) {
109*4882a593Smuzhiyun links[i] = bpf_program__attach(prog);
110*4882a593Smuzhiyun if (libbpf_get_error(links[i])) {
111*4882a593Smuzhiyun fprintf(stderr, "ERROR: bpf_program__attach failed\n");
112*4882a593Smuzhiyun links[i] = NULL;
113*4882a593Smuzhiyun goto cleanup;
114*4882a593Smuzhiyun }
115*4882a593Smuzhiyun i++;
116*4882a593Smuzhiyun }
117*4882a593Smuzhiyun
118*4882a593Smuzhiyun while (1) {
119*4882a593Smuzhiyun get_data(map_fd);
120*4882a593Smuzhiyun print_hist();
121*4882a593Smuzhiyun sleep(5);
122*4882a593Smuzhiyun }
123*4882a593Smuzhiyun
124*4882a593Smuzhiyun cleanup:
125*4882a593Smuzhiyun for (i--; i >= 0; i--)
126*4882a593Smuzhiyun bpf_link__destroy(links[i]);
127*4882a593Smuzhiyun
128*4882a593Smuzhiyun bpf_object__close(obj);
129*4882a593Smuzhiyun return 0;
130*4882a593Smuzhiyun }
131