cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

lathist_user.c (2660B)


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