LXR linux/samples/bpf/tracex4

   1/* Copyright (c) 2015 PLUMgrid, http://plumgrid.com
   2 *
   3 * This program is free software; you can redistribute it and/or
   4 * modify it under the terms of version 2 of the GNU General Public
   5 * License as published by the Free Software Foundation.
   6 */
   7#include <stdio.h>
   8#include <stdlib.h>
   9#include <signal.h>
  10#include <unistd.h>
  11#include <stdbool.h>
  12#include <string.h>
  13#include <time.h>
  14#include <linux/bpf.h>
  15#include <sys/resource.h>
  16
  17#include "libbpf.h"
  18#include "bpf_load.h"
  19
  20struct pair {
  21        long long val;
  22        __u64 ip;
  23};
  24
  25static __u64 time_get_ns(void)
  26{
  27        struct timespec ts;
  28
  29        clock_gettime(CLOCK_MONOTONIC, &ts);
  30        return ts.tv_sec * 1000000000ull + ts.tv_nsec;
  31}
  32
  33static void print_old_objects(int fd)
  34{
  35        long long val = time_get_ns();
  36        __u64 key, next_key;
  37        struct pair v;
  38
  39        key = write(1, "\e[1;1H\e[2J", 12); /* clear screen */
  40
  41        key = -1;
  42        while (bpf_map_get_next_key(map_fd[0], &key, &next_key) == 0) {
  43                bpf_map_lookup_elem(map_fd[0], &next_key, &v);
  44                key = next_key;
  45                if (val - v.val < 1000000000ll)
  46                        /* object was allocated more then 1 sec ago */
  47                        continue;
  48                printf("obj 0x%llx is %2lldsec old was allocated at ip %llx\n",
  49                       next_key, (val - v.val) / 1000000000ll, v.ip);
  50        }
  51}
  52
  53int main(int ac, char **argv)
  54{
  55        struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
  56        char filename[256];
  57        int i;
  58
  59        snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
  60
  61        if (setrlimit(RLIMIT_MEMLOCK, &r)) {
  62                perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
  63                return 1;
  64        }
  65
  66        if (load_bpf_file(filename)) {
  67                printf("%s", bpf_log_buf);
  68                return 1;
  69        }
  70
  71        for (i = 0; ; i++) {
  72                print_old_objects(map_fd[1]);
  73                sleep(1);
  74        }
  75
  76        return 0;
  77}
  78