xref: /freebsd/contrib/ofed/opensm/libvendor/osm_pkt_randomizer.c (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*
2  * Copyright (c) 2004-2008 Voltaire, Inc. All rights reserved.
3  * Copyright (c) 2002-2005 Mellanox Technologies LTD. All rights reserved.
4  * Copyright (c) 1996-2003 Intel Corporation. All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the
10  * OpenIB.org BSD license below:
11  *
12  *     Redistribution and use in source and binary forms, with or
13  *     without modification, are permitted provided that the following
14  *     conditions are met:
15  *
16  *      - Redistributions of source code must retain the above
17  *        copyright notice, this list of conditions and the following
18  *        disclaimer.
19  *
20  *      - Redistributions in binary form must reproduce the above
21  *        copyright notice, this list of conditions and the following
22  *        disclaimer in the documentation and/or other materials
23  *        provided with the distribution.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32  * SOFTWARE.
33  *
34  */
35 
36 /*
37  * Abstract:
38  *    Implementation of osm_pkt_randomizer_t.
39  *
40  */
41 
42 #if HAVE_CONFIG_H
43 #  include <config.h>
44 #endif				/* HAVE_CONFIG_H */
45 
46 #include <vendor/osm_pkt_randomizer.h>
47 #include <stdlib.h>
48 #include <string.h>
49 
50 #ifndef __WIN__
51 #include <sys/time.h>
52 #include <unistd.h>
53 #endif
54 
55 /**********************************************************************
56  * Return TRUE if the path is in a fault path, and FALSE otherwise.
57  * By in a fault path the meaning is that there is a path in the fault
58  * paths that the given path includes it.
59  * E.g: if there is a fault path: 0,1,4
60  * For the given path: 0,1,4,7 the return value will be TRUE, also for
61  * the given path: 0,1,4 the return value will be TRUE, but for
62  * the given paths: 0,1 or 0,3,1,4 - the return value will be FALSE.
63  **********************************************************************/
64 boolean_t
65 __osm_pkt_randomizer_is_path_in_fault_paths(IN osm_log_t * p_log,
66 					    IN osm_dr_path_t * p_dr_path,
67 					    IN osm_pkt_randomizer_t *
68 					    p_pkt_rand)
69 {
70 	boolean_t res = FALSE, found_path;
71 	osm_dr_path_t *p_found_dr_path;
72 	uint8_t ind1, ind2;
73 
74 	OSM_LOG_ENTER(p_log);
75 
76 	for (ind1 = 0; ind1 < p_pkt_rand->num_paths_initialized; ind1++) {
77 		found_path = TRUE;
78 		p_found_dr_path = &(p_pkt_rand->fault_dr_paths[ind1]);
79 		/* if the hop count of the found path is greater than the
80 		   hop count of the input path - then it is not part of it.
81 		   Check the next path. */
82 		if (p_found_dr_path->hop_count > p_dr_path->hop_count)
83 			continue;
84 
85 		/* go over all the ports in the found path and see if they match
86 		   the ports in the input path */
87 		for (ind2 = 0; ind2 <= p_found_dr_path->hop_count; ind2++)
88 			if (p_found_dr_path->path[ind2] !=
89 			    p_dr_path->path[ind2])
90 				found_path = FALSE;
91 
92 		/* If found_path is TRUE  then there is a full match of the path */
93 		if (found_path == TRUE) {
94 			OSM_LOG(p_log, OSM_LOG_VERBOSE,
95 				"Given path is in a fault path\n");
96 			res = TRUE;
97 			break;
98 		}
99 	}
100 
101 	OSM_LOG_EXIT(p_log);
102 	return res;
103 }
104 
105 /**********************************************************************
106  * For a given dr_path - return TRUE if the path should be dropped,
107  * return FALSE otherwise.
108  * The check uses random criteria in order to determine whether or not
109  * the path should be dropped.
110  * First - if not all paths are initialized, it randomally chooses if
111  * to use this path as a fault path or not.
112  * Second - if the path is in the fault paths (meaning - it is equal
113  * to or includes one of the fault paths) - then it randomally chooses
114  * if to drop it or not.
115  **********************************************************************/
116 boolean_t
117 __osm_pkt_randomizer_process_path(IN osm_log_t * p_log,
118 				  IN osm_pkt_randomizer_t * p_pkt_rand,
119 				  IN osm_dr_path_t * p_dr_path)
120 {
121 	boolean_t res = FALSE;
122 	static boolean_t rand_value_init = FALSE;
123 	static int rand_value;
124 	boolean_t in_fault_paths;
125 	uint8_t i;
126 	char buf[BUF_SIZE];
127 	char line[BUF_SIZE];
128 
129 	OSM_LOG_ENTER(p_log);
130 
131 	if (rand_value_init == FALSE) {
132 		int seed;
133 #ifdef __WIN__
134 		SYSTEMTIME st;
135 #else
136 		struct timeval tv;
137 		struct timezone tz;
138 #endif				/*  __WIN__ */
139 
140 		/* initiate the rand_value according to timeofday */
141 		rand_value_init = TRUE;
142 
143 #ifdef __WIN__
144 		GetLocalTime(&st);
145 		seed = st.wMilliseconds;
146 #else
147 		gettimeofday(&tv, &tz);
148 		seed = tv.tv_usec;
149 #endif				/*  __WIN__ */
150 
151 		srand(seed);
152 	}
153 
154 	/* If the hop_count is 1 - then this is a mad down to our local port - don't drop it */
155 	if (p_dr_path->hop_count <= 1)
156 		goto Exit;
157 
158 	rand_value = rand();
159 
160 	sprintf(buf, "Path: ");
161 	/* update the dr_path into the buf */
162 	for (i = 0; i <= p_dr_path->hop_count; i++) {
163 		sprintf(line, "[%X]", p_dr_path->path[i]);
164 		strcat(buf, line);
165 	}
166 
167 	/* Check if the path given is in one of the fault paths */
168 	in_fault_paths =
169 	    __osm_pkt_randomizer_is_path_in_fault_paths(p_log, p_dr_path,
170 							p_pkt_rand);
171 
172 	/* Check if all paths are initialized */
173 	if (p_pkt_rand->num_paths_initialized <
174 	    p_pkt_rand->osm_pkt_num_unstable_links) {
175 		/* Not all packets are initialized. */
176 		if (in_fault_paths == FALSE) {
177 			/* the path is not in the false paths. Check using the rand value
178 			   if to update it there or not. */
179 			if (rand_value %
180 			    (p_pkt_rand->osm_pkt_unstable_link_rate) == 0) {
181 				OSM_LOG(p_log, OSM_LOG_VERBOSE,
182 					"%s added to the fault_dr_paths list\n"
183 					"\t\t\t rand_value:%u, unstable_link_rate:%u \n",
184 					buf, rand_value,
185 					p_pkt_rand->osm_pkt_unstable_link_rate);
186 
187 				/* update the path in the fault paths */
188 				memcpy(&
189 				       (p_pkt_rand->
190 					fault_dr_paths[p_pkt_rand->
191 						       num_paths_initialized]),
192 				       p_dr_path, sizeof(osm_dr_path_t));
193 				p_pkt_rand->num_paths_initialized++;
194 				in_fault_paths = TRUE;
195 			}
196 		}
197 	}
198 
199 	if (in_fault_paths == FALSE) {
200 		/* If in_fault_paths is FALSE - just ignore the path */
201 		OSM_LOG(p_log, OSM_LOG_VERBOSE, "%s not in fault paths\n", buf);
202 		goto Exit;
203 	}
204 
205 	/* The path is in the fault paths. Need to choose (randomally if to drop it
206 	   or not. */
207 	rand_value = rand();
208 
209 	if (rand_value % (p_pkt_rand->osm_pkt_drop_rate) == 0) {
210 		/* drop the current packet */
211 		res = TRUE;
212 		OSM_LOG(p_log, OSM_LOG_VERBOSE, "Dropping path:%s\n", buf);
213 	}
214 
215 Exit:
216 	OSM_LOG_EXIT(p_log);
217 	return res;
218 }
219 
220 boolean_t
221 osm_pkt_randomizer_mad_drop(IN osm_log_t * p_log,
222 			    IN osm_pkt_randomizer_t * p_pkt_randomizer,
223 			    IN const ib_mad_t * p_mad)
224 {
225 	const ib_smp_t *p_smp;
226 	boolean_t res = FALSE;
227 	osm_dr_path_t dr_path;
228 
229 	OSM_LOG_ENTER(p_log);
230 
231 	p_smp = (ib_smp_t *) p_mad;
232 
233 	if (p_smp->mgmt_class != IB_MCLASS_SUBN_DIR)
234 		/* This is a lid route mad. Don't drop it */
235 		goto Exit;
236 
237 	osm_dr_path_init(&dr_path, p_smp->hop_count, p_smp->initial_path);
238 
239 	if (__osm_pkt_randomizer_process_path
240 	    (p_log, p_pkt_randomizer, &dr_path)) {
241 		/* the mad should be dropped o */
242 		OSM_LOG(p_log, OSM_LOG_VERBOSE,
243 			"mad TID: 0x%" PRIx64 " is being dropped\n",
244 			cl_ntoh64(p_smp->trans_id));
245 		res = TRUE;
246 	}
247 
248 Exit:
249 	OSM_LOG_EXIT(p_log);
250 	return res;
251 }
252 
253 ib_api_status_t
254 osm_pkt_randomizer_init(IN OUT osm_pkt_randomizer_t ** pp_pkt_randomizer,
255 			IN osm_log_t * p_log)
256 {
257 	uint8_t tmp;
258 	ib_api_status_t res = IB_SUCCESS;
259 
260 	OSM_LOG_ENTER(p_log);
261 
262 	*pp_pkt_randomizer = malloc(sizeof(osm_pkt_randomizer_t));
263 	if (*pp_pkt_randomizer == NULL) {
264 		res = IB_INSUFFICIENT_MEMORY;
265 		goto Exit;
266 	}
267 	memset(*pp_pkt_randomizer, 0, sizeof(osm_pkt_randomizer_t));
268 	(*pp_pkt_randomizer)->num_paths_initialized = 0;
269 
270 	tmp = atol(getenv("OSM_PKT_DROP_RATE"));
271 	(*pp_pkt_randomizer)->osm_pkt_drop_rate = tmp;
272 
273 	if (getenv("OSM_PKT_NUM_UNSTABLE_LINKS") != NULL
274 	    && (tmp = atol(getenv("OSM_PKT_NUM_UNSTABLE_LINKS"))) > 0)
275 		(*pp_pkt_randomizer)->osm_pkt_num_unstable_links = tmp;
276 	else
277 		(*pp_pkt_randomizer)->osm_pkt_num_unstable_links = 1;
278 
279 	if (getenv("OSM_PKT_UNSTABLE_LINK_RATE") != NULL
280 	    && (tmp = atol(getenv("OSM_PKT_UNSTABLE_LINK_RATE"))) > 0)
281 		(*pp_pkt_randomizer)->osm_pkt_unstable_link_rate = tmp;
282 	else
283 		(*pp_pkt_randomizer)->osm_pkt_unstable_link_rate = 20;
284 
285 	OSM_LOG(p_log, OSM_LOG_VERBOSE, "Using OSM_PKT_DROP_RATE=%u \n"
286 		"\t\t\t\t OSM_PKT_NUM_UNSTABLE_LINKS=%u \n"
287 		"\t\t\t\t OSM_PKT_UNSTABLE_LINK_RATE=%u \n",
288 		(*pp_pkt_randomizer)->osm_pkt_drop_rate,
289 		(*pp_pkt_randomizer)->osm_pkt_num_unstable_links,
290 		(*pp_pkt_randomizer)->osm_pkt_unstable_link_rate);
291 
292 	/* allocate the fault_dr_paths variable */
293 	/* It is the number of the paths that will be saved as fault = osm_pkt_num_unstable_links */
294 	(*pp_pkt_randomizer)->fault_dr_paths = malloc(sizeof(osm_dr_path_t) *
295 						      (*pp_pkt_randomizer)->
296 						      osm_pkt_num_unstable_links);
297 	if ((*pp_pkt_randomizer)->fault_dr_paths == NULL) {
298 		res = IB_INSUFFICIENT_MEMORY;
299 		goto Exit;
300 	}
301 
302 	memset((*pp_pkt_randomizer)->fault_dr_paths, 0,
303 	       sizeof(osm_dr_path_t) *
304 	       (*pp_pkt_randomizer)->osm_pkt_num_unstable_links);
305 
306 Exit:
307 	OSM_LOG_EXIT(p_log);
308 	return (res);
309 }
310 
311 void
312 osm_pkt_randomizer_destroy(IN OUT osm_pkt_randomizer_t ** pp_pkt_randomizer,
313 			   IN osm_log_t * p_log)
314 {
315 	OSM_LOG_ENTER(p_log);
316 
317 	if (*pp_pkt_randomizer != NULL) {
318 		free((*pp_pkt_randomizer)->fault_dr_paths);
319 		free(*pp_pkt_randomizer);
320 	}
321 	OSM_LOG_EXIT(p_log);
322 }
323