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 "libbpf.h"
  16 #include "bpf_load.h"
  17
  18 struct pair {
  19         long long val;
  20         __u64 ip;
  21 };
  22
  23 static __u64 time_get_ns(void)
  24 {
  25         struct timespec ts;
  26
  27         clock_gettime(CLOCK_MONOTONIC, &ts);
  28         return ts.tv_sec * 1000000000ull + ts.tv_nsec;
  29 }
  30
  31 static void print_old_objects(int fd)
  32 {
  33         long long val = time_get_ns();
  34         __u64 key, next_key;
  35         struct pair v;
  36
  37         key = write(1, "\e[1;1H\e[2J", 12); /* clear screen */
  38
  39         key = -1;
  40         while (bpf_get_next_key(map_fd[0], &key, &next_key) == 0) {
  41                 bpf_lookup_elem(map_fd[0], &next_key, &v);
  42                 key = next_key;
  43                 if (val - v.val < 1000000000ll)
  44                         /* object was allocated more then 1 sec ago */
  45                         continue;
  46                 printf("obj 0x%llx is %2lldsec old was allocated at ip %llx\n",
  47                        next_key, (val - v.val) / 1000000000ll, v.ip);
  48         }
  49 }
  50
  51 int main(int ac, char **argv)
  52 {
  53         char filename[256];
  54         int i;
  55
  56         snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
  57
  58         if (load_bpf_file(filename)) {
  59                 printf("%s", bpf_log_buf);
  60                 return 1;
  61         }
  62
  63         for (i = 0; ; i++) {
  64                 print_old_objects(map_fd[1]);
  65                 sleep(1);
  66         }
  67
  68         return 0;
  69 }