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