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 WIN32
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 **********************************************************************/
64boolean_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 **********************************************************************/
116boolean_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 WIN32
134		SYSTEMTIME st;
135#else
136		struct timeval tv;
137		struct timezone tz;
138#endif				/*  WIN32 */
139
140		/* initiate the rand_value according to timeofday */
141		rand_value_init = TRUE;
142
143#ifdef WIN32
144		GetLocalTime(&st);
145		seed = st.wMilliseconds;
146#else
147		gettimeofday(&tv, &tz);
148		seed = tv.tv_usec;
149#endif				/*  WIN32 */
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
215Exit:
216	OSM_LOG_EXIT(p_log);
217	return res;
218}
219
220/**********************************************************************
221 **********************************************************************/
222boolean_t
223osm_pkt_randomizer_mad_drop(IN osm_log_t * p_log,
224			    IN osm_pkt_randomizer_t * p_pkt_randomizer,
225			    IN const ib_mad_t * p_mad)
226{
227	const ib_smp_t *p_smp;
228	boolean_t res = FALSE;
229	osm_dr_path_t dr_path;
230
231	OSM_LOG_ENTER(p_log);
232
233	p_smp = (ib_smp_t *) p_mad;
234
235	if (p_smp->mgmt_class != IB_MCLASS_SUBN_DIR)
236		/* This is a lid route mad. Don't drop it */
237		goto Exit;
238
239	osm_dr_path_init(&dr_path, 0,	/* The h_bind is not really important for us to save */
240			 p_smp->hop_count, p_smp->initial_path);
241
242	if (__osm_pkt_randomizer_process_path
243	    (p_log, p_pkt_randomizer, &dr_path)) {
244		/* the mad should be dropped o */
245		OSM_LOG(p_log, OSM_LOG_VERBOSE,
246			"mad TID: 0x%" PRIx64 " is being dropped\n",
247			cl_ntoh64(p_smp->trans_id));
248		res = TRUE;
249	}
250
251Exit:
252	OSM_LOG_EXIT(p_log);
253	return res;
254}
255
256/**********************************************************************
257 **********************************************************************/
258ib_api_status_t
259osm_pkt_randomizer_init(IN OUT osm_pkt_randomizer_t ** pp_pkt_randomizer,
260			IN osm_log_t * p_log)
261{
262	uint8_t tmp;
263	ib_api_status_t res = IB_SUCCESS;
264
265	OSM_LOG_ENTER(p_log);
266
267	*pp_pkt_randomizer = malloc(sizeof(osm_pkt_randomizer_t));
268	if (*pp_pkt_randomizer == NULL) {
269		res = IB_INSUFFICIENT_MEMORY;
270		goto Exit;
271	}
272	memset(*pp_pkt_randomizer, 0, sizeof(osm_pkt_randomizer_t));
273	(*pp_pkt_randomizer)->num_paths_initialized = 0;
274
275	tmp = atol(getenv("OSM_PKT_DROP_RATE"));
276	(*pp_pkt_randomizer)->osm_pkt_drop_rate = tmp;
277
278	if (getenv("OSM_PKT_NUM_UNSTABLE_LINKS") != NULL
279	    && (tmp = atol(getenv("OSM_PKT_NUM_UNSTABLE_LINKS"))) > 0)
280		(*pp_pkt_randomizer)->osm_pkt_num_unstable_links = tmp;
281	else
282		(*pp_pkt_randomizer)->osm_pkt_num_unstable_links = 1;
283
284	if (getenv("OSM_PKT_UNSTABLE_LINK_RATE") != NULL
285	    && (tmp = atol(getenv("OSM_PKT_UNSTABLE_LINK_RATE"))) > 0)
286		(*pp_pkt_randomizer)->osm_pkt_unstable_link_rate = tmp;
287	else
288		(*pp_pkt_randomizer)->osm_pkt_unstable_link_rate = 20;
289
290	OSM_LOG(p_log, OSM_LOG_VERBOSE, "Using OSM_PKT_DROP_RATE=%u \n"
291		"\t\t\t\t OSM_PKT_NUM_UNSTABLE_LINKS=%u \n"
292		"\t\t\t\t OSM_PKT_UNSTABLE_LINK_RATE=%u \n",
293		(*pp_pkt_randomizer)->osm_pkt_drop_rate,
294		(*pp_pkt_randomizer)->osm_pkt_num_unstable_links,
295		(*pp_pkt_randomizer)->osm_pkt_unstable_link_rate);
296
297	/* allocate the fault_dr_paths variable */
298	/* It is the number of the paths that will be saved as fault = osm_pkt_num_unstable_links */
299	(*pp_pkt_randomizer)->fault_dr_paths = malloc(sizeof(osm_dr_path_t) *
300						      (*pp_pkt_randomizer)->
301						      osm_pkt_num_unstable_links);
302	if ((*pp_pkt_randomizer)->fault_dr_paths == NULL) {
303		res = IB_INSUFFICIENT_MEMORY;
304		goto Exit;
305	}
306
307	memset((*pp_pkt_randomizer)->fault_dr_paths, 0,
308	       sizeof(osm_dr_path_t) *
309	       (*pp_pkt_randomizer)->osm_pkt_num_unstable_links);
310
311Exit:
312	OSM_LOG_EXIT(p_log);
313	return (res);
314}
315
316/**********************************************************************
317 **********************************************************************/
318void
319osm_pkt_randomizer_destroy(IN OUT osm_pkt_randomizer_t ** pp_pkt_randomizer,
320			   IN osm_log_t * p_log)
321{
322	OSM_LOG_ENTER(p_log);
323
324	if (*pp_pkt_randomizer != NULL) {
325		free((*pp_pkt_randomizer)->fault_dr_paths);
326		free(*pp_pkt_randomizer);
327	}
328	OSM_LOG_EXIT(p_log);
329}
330