samples/bpf/tracex4_user.c

   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
  20 struct pair {
  21         long long val;
  22         __u64 ip;
  23 };
  24
  25 static __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
  33 static 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
  53 int 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 }