tests/heavy-wq.c

   1 /*
   2  * $Id$
   3  *
   4  * This file is part of Quagga.
   5  *
   6  * Quagga is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2, or (at your option) any
   9  * later version.
  10  *
  11  * Quagga is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with Quagga; see the file COPYING.  If not, write to the Free
  18  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  19  * 02111-1307, USA.
  20  */
  21
  22 /* This programme shows the effects of 'heavy' long-running functions
  23  * on the cooperative threading model.
  24  *
  25  * Run it with a config file containing 'password whatever', telnet to it
  26  * (it defaults to port 4000) and enter the 'clear foo string' command.
  27  * then type whatever and observe that the vty interface is unresponsive
  28  * for quite a period of time, due to the clear_something command
  29  * taking a very long time to complete.
  30  */
  31 #include <zebra.h>
  32
  33 #include "thread.h"
  34 #include "vty.h"
  35 #include "command.h"
  36 #include "memory.h"
  37 #include "log.h"
  38 #include "workqueue.h"
  39 #include <math.h>
  40
  41 extern struct thread_master *master;
  42 static struct work_queue *heavy_wq;
  43
  44 struct heavy_wq_node
  45 {
  46   char *str;
  47   int i;
  48 };
  49
  50 enum
  51 {
  52   ITERS_FIRST = 0,
  53   ITERS_ERR = 100,
  54   ITERS_LATER = 400,
  55   ITERS_PRINT = 10,
  56   ITERS_MAX = 1000,
  57 };
  58
  59 static void
  60 heavy_wq_add (struct vty *vty, const char *str, int i)
  61 {
  62   struct heavy_wq_node *hn;
  63
  64   if ((hn = XCALLOC (MTYPE_PREFIX_LIST, sizeof(struct heavy_wq_node))) == NULL)
  65     {
  66       zlog_err ("%s: unable to allocate hn", __func__);
  67       return;
  68     }
  69
  70   hn->i = i;
  71   if (!(hn->str = XSTRDUP (MTYPE_PREFIX_LIST_STR, str)))
  72     {
  73       zlog_err ("%s: unable to xstrdup", __func__);
  74       XFREE (MTYPE_PREFIX_LIST, hn);
  75       return;
  76     }
  77
  78   work_queue_add (heavy_wq, hn);
  79
  80   return;
  81 }
  82
  83 static void
  84 slow_func_err (struct work_queue *wq, struct work_queue_item *item)
  85 {
  86   printf ("%s: running error function\n", __func__);
  87 }
  88
  89 static void
  90 slow_func_del (struct work_queue *wq, void *data)
  91 {
  92   struct heavy_wq_node *hn = data;
  93   assert (hn && hn->str);
  94   printf ("%s: %s\n", __func__, hn->str);
  95   XFREE (MTYPE_PREFIX_LIST_STR, hn->str);
  96   hn->str = NULL;
  97   XFREE(MTYPE_PREFIX_LIST, hn);
  98 }
  99
 100 static wq_item_status
 101 slow_func (struct work_queue *wq, void *data)
 102 {
 103   struct heavy_wq_node *hn = data;
 104   double x = 1;
 105   int j;
 106
 107   assert (hn && hn->str);
 108
 109   for (j = 0; j < 300; j++)
 110     x += sin(x)*j;
 111
 112   if ((hn->i % ITERS_LATER) == 0)
 113     return WQ_RETRY_LATER;
 114
 115   if ((hn->i % ITERS_ERR) == 0)
 116     return WQ_RETRY_NOW;
 117
 118   if ((hn->i % ITERS_PRINT) == 0)
 119     printf ("%s did %d, x = %g\n", hn->str, hn->i, x);
 120
 121   return WQ_SUCCESS;
 122 }
 123
 124 static void
 125 clear_something (struct vty *vty, const char *str)
 126 {
 127   int i;
 128
 129   /* this could be like iterating through 150k of route_table
 130    * or worse, iterating through a list of peers, to bgp_stop them with
 131    * each having 150k route tables to process...
 132    */
 133   for (i = ITERS_FIRST; i < ITERS_MAX; i++)
 134     heavy_wq_add (vty, str, i);
 135 }
 136
 137 DEFUN (clear_foo,
 138        clear_foo_cmd,
 139        "clear foo .LINE",
 140        "clear command\n"
 141        "arbitrary string\n")
 142 {
 143   char *str;
 144   if (!argc)
 145     {
 146       vty_out (vty, "%% string argument required%s", VTY_NEWLINE);
 147       return CMD_WARNING;
 148     }
 149
 150   str = argv_concat (argv, argc, 0);
 151
 152   clear_something (vty, str);
 153   XFREE (MTYPE_TMP, str);
 154   return CMD_SUCCESS;
 155 }
 156
 157 static int
 158 heavy_wq_init ()
 159 {
 160   if (! (heavy_wq = work_queue_new (master, "heavy_work_queue")))
 161     {
 162       zlog_err ("%s: could not get new work queue!", __func__);
 163       return -1;
 164     }
 165
 166   heavy_wq->spec.workfunc = &slow_func;
 167   heavy_wq->spec.errorfunc = &slow_func_err;
 168   heavy_wq->spec.del_item_data = &slow_func_del;
 169   heavy_wq->spec.max_retries = 3;
 170   heavy_wq->spec.hold = 1000;
 171
 172   return 0;
 173 }
 174
 175 void
 176 test_init()
 177 {
 178   install_element (VIEW_NODE, &clear_foo_cmd);
 179   heavy_wq_init();
 180 }