tests/lib/test_heavy.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  */
   4
   5 /* This programme shows the effects of 'heavy' long-running functions
   6  * on the cooperative threading model.
   7  *
   8  * Run it with a config file containing 'password whatever', telnet to it
   9  * (it defaults to port 4000) and enter the 'clear foo string' command.
  10  * then type whatever and observe that the vty interface is unresponsive
  11  * for quite a period of time, due to the clear_something command
  12  * taking a very long time to complete.
  13  */
  14 #include <zebra.h>
  15
  16 #include "thread.h"
  17 #include "vty.h"
  18 #include "command.h"
  19 #include "memory.h"
  20 #include <math.h>
  21
  22 #include "tests.h"
  23
  24 enum { ITERS_FIRST = 0,
  25        ITERS_ERR = 100,
  26        ITERS_LATER = 400,
  27        ITERS_PRINT = 10,
  28        ITERS_MAX = 1000,
  29 };
  30
  31 static void slow_func(struct vty *vty, const char *str, const int i)
  32 {
  33         double x = 1;
  34         int j;
  35
  36         for (j = 0; j < 300; j++)
  37                 x += sin(x) * j;
  38
  39         if ((i % ITERS_LATER) == 0)
  40                 printf("%s: %d, temporary error, save this somehow and do it later..\n",
  41                        __func__, i);
  42
  43         if ((i % ITERS_ERR) == 0)
  44                 printf("%s: hard error\n", __func__);
  45
  46         if ((i % ITERS_PRINT) == 0)
  47                 printf("%s did %d, x = %g\n", str, i, x);
  48 }
  49
  50 static void clear_something(struct vty *vty, const char *str)
  51 {
  52         int i;
  53
  54         /* this could be like iterating through 150k of route_table
  55          * or worse, iterating through a list of peers, to bgp_stop them with
  56          * each having 150k route tables to process...
  57          */
  58         for (i = ITERS_FIRST; i < ITERS_MAX; i++)
  59                 slow_func(vty, str, i);
  60 }
  61
  62 DEFUN (clear_foo,
  63        clear_foo_cmd,
  64        "clear foo LINE...",
  65        "clear command\n"
  66        "arbitrary string\n")
  67 {
  68         char *str;
  69         if (!argc) {
  70                 vty_out(vty, "%% string argument required\n");
  71                 return CMD_WARNING;
  72         }
  73
  74         str = argv_concat(argv, argc, 0);
  75
  76         clear_something(vty, str);
  77         XFREE(MTYPE_TMP, str);
  78         return CMD_SUCCESS;
  79 }
  80
  81 static void slow_vty_init(void)
  82 {
  83         install_element(VIEW_NODE, &clear_foo_cmd);
  84 }
  85
  86 void test_init(void)
  87 {
  88         slow_vty_init();
  89 }