1 /*
2 * GPL HEADER START
3 *
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
19 *
20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21 * CA 95054 USA or visit www.sun.com if you need additional information or
22 * have any questions.
23 *
24 * GPL HEADER END
25 */
26 /*
27 * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
29 *
30 * Copyright (c) 2012, Intel Corporation.
31 */
32 /*
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
35 *
36 * lnet/lnet/peer.c
37 */
38
39 #define DEBUG_SUBSYSTEM S_LNET
40
41 #include "../../include/linux/lnet/lib-lnet.h"
42
43 int
lnet_peer_tables_create(void)44 lnet_peer_tables_create(void)
45 {
46 struct lnet_peer_table *ptable;
47 struct list_head *hash;
48 int i;
49 int j;
50
51 the_lnet.ln_peer_tables = cfs_percpt_alloc(lnet_cpt_table(),
52 sizeof(*ptable));
53 if (the_lnet.ln_peer_tables == NULL) {
54 CERROR("Failed to allocate cpu-partition peer tables\n");
55 return -ENOMEM;
56 }
57
58 cfs_percpt_for_each(ptable, i, the_lnet.ln_peer_tables) {
59 INIT_LIST_HEAD(&ptable->pt_deathrow);
60
61 LIBCFS_CPT_ALLOC(hash, lnet_cpt_table(), i,
62 LNET_PEER_HASH_SIZE * sizeof(*hash));
63 if (hash == NULL) {
64 CERROR("Failed to create peer hash table\n");
65 lnet_peer_tables_destroy();
66 return -ENOMEM;
67 }
68
69 for (j = 0; j < LNET_PEER_HASH_SIZE; j++)
70 INIT_LIST_HEAD(&hash[j]);
71 ptable->pt_hash = hash; /* sign of initialization */
72 }
73
74 return 0;
75 }
76
77 void
lnet_peer_tables_destroy(void)78 lnet_peer_tables_destroy(void)
79 {
80 struct lnet_peer_table *ptable;
81 struct list_head *hash;
82 int i;
83 int j;
84
85 if (the_lnet.ln_peer_tables == NULL)
86 return;
87
88 cfs_percpt_for_each(ptable, i, the_lnet.ln_peer_tables) {
89 hash = ptable->pt_hash;
90 if (hash == NULL) /* not intialized */
91 break;
92
93 LASSERT(list_empty(&ptable->pt_deathrow));
94
95 ptable->pt_hash = NULL;
96 for (j = 0; j < LNET_PEER_HASH_SIZE; j++)
97 LASSERT(list_empty(&hash[j]));
98
99 LIBCFS_FREE(hash, LNET_PEER_HASH_SIZE * sizeof(*hash));
100 }
101
102 cfs_percpt_free(the_lnet.ln_peer_tables);
103 the_lnet.ln_peer_tables = NULL;
104 }
105
106 void
lnet_peer_tables_cleanup(void)107 lnet_peer_tables_cleanup(void)
108 {
109 struct lnet_peer_table *ptable;
110 int i;
111 int j;
112
113 LASSERT(the_lnet.ln_shutdown); /* i.e. no new peers */
114
115 cfs_percpt_for_each(ptable, i, the_lnet.ln_peer_tables) {
116 lnet_net_lock(i);
117
118 for (j = 0; j < LNET_PEER_HASH_SIZE; j++) {
119 struct list_head *peers = &ptable->pt_hash[j];
120
121 while (!list_empty(peers)) {
122 lnet_peer_t *lp = list_entry(peers->next,
123 lnet_peer_t,
124 lp_hashlist);
125 list_del_init(&lp->lp_hashlist);
126 /* lose hash table's ref */
127 lnet_peer_decref_locked(lp);
128 }
129 }
130
131 lnet_net_unlock(i);
132 }
133
134 cfs_percpt_for_each(ptable, i, the_lnet.ln_peer_tables) {
135 LIST_HEAD (deathrow);
136 lnet_peer_t *lp;
137
138 lnet_net_lock(i);
139
140 for (j = 3; ptable->pt_number != 0; j++) {
141 lnet_net_unlock(i);
142
143 if ((j & (j - 1)) == 0) {
144 CDEBUG(D_WARNING,
145 "Waiting for %d peers on peer table\n",
146 ptable->pt_number);
147 }
148 set_current_state(TASK_UNINTERRUPTIBLE);
149 schedule_timeout(cfs_time_seconds(1) / 2);
150 lnet_net_lock(i);
151 }
152 list_splice_init(&ptable->pt_deathrow, &deathrow);
153
154 lnet_net_unlock(i);
155
156 while (!list_empty(&deathrow)) {
157 lp = list_entry(deathrow.next,
158 lnet_peer_t, lp_hashlist);
159 list_del(&lp->lp_hashlist);
160 LIBCFS_FREE(lp, sizeof(*lp));
161 }
162 }
163 }
164
165 void
lnet_destroy_peer_locked(lnet_peer_t * lp)166 lnet_destroy_peer_locked(lnet_peer_t *lp)
167 {
168 struct lnet_peer_table *ptable;
169
170 LASSERT(lp->lp_refcount == 0);
171 LASSERT(lp->lp_rtr_refcount == 0);
172 LASSERT(list_empty(&lp->lp_txq));
173 LASSERT(list_empty(&lp->lp_hashlist));
174 LASSERT(lp->lp_txqnob == 0);
175
176 ptable = the_lnet.ln_peer_tables[lp->lp_cpt];
177 LASSERT(ptable->pt_number > 0);
178 ptable->pt_number--;
179
180 lnet_ni_decref_locked(lp->lp_ni, lp->lp_cpt);
181 lp->lp_ni = NULL;
182
183 list_add(&lp->lp_hashlist, &ptable->pt_deathrow);
184 }
185
186 lnet_peer_t *
lnet_find_peer_locked(struct lnet_peer_table * ptable,lnet_nid_t nid)187 lnet_find_peer_locked(struct lnet_peer_table *ptable, lnet_nid_t nid)
188 {
189 struct list_head *peers;
190 lnet_peer_t *lp;
191
192 LASSERT(!the_lnet.ln_shutdown);
193
194 peers = &ptable->pt_hash[lnet_nid2peerhash(nid)];
195 list_for_each_entry(lp, peers, lp_hashlist) {
196 if (lp->lp_nid == nid) {
197 lnet_peer_addref_locked(lp);
198 return lp;
199 }
200 }
201
202 return NULL;
203 }
204
205 int
lnet_nid2peer_locked(lnet_peer_t ** lpp,lnet_nid_t nid,int cpt)206 lnet_nid2peer_locked(lnet_peer_t **lpp, lnet_nid_t nid, int cpt)
207 {
208 struct lnet_peer_table *ptable;
209 lnet_peer_t *lp = NULL;
210 lnet_peer_t *lp2;
211 int cpt2;
212 int rc = 0;
213
214 *lpp = NULL;
215 if (the_lnet.ln_shutdown) /* it's shutting down */
216 return -ESHUTDOWN;
217
218 /* cpt can be LNET_LOCK_EX if it's called from router functions */
219 cpt2 = cpt != LNET_LOCK_EX ? cpt : lnet_cpt_of_nid_locked(nid);
220
221 ptable = the_lnet.ln_peer_tables[cpt2];
222 lp = lnet_find_peer_locked(ptable, nid);
223 if (lp != NULL) {
224 *lpp = lp;
225 return 0;
226 }
227
228 if (!list_empty(&ptable->pt_deathrow)) {
229 lp = list_entry(ptable->pt_deathrow.next,
230 lnet_peer_t, lp_hashlist);
231 list_del(&lp->lp_hashlist);
232 }
233
234 /*
235 * take extra refcount in case another thread has shutdown LNet
236 * and destroyed locks and peer-table before I finish the allocation
237 */
238 ptable->pt_number++;
239 lnet_net_unlock(cpt);
240
241 if (lp != NULL)
242 memset(lp, 0, sizeof(*lp));
243 else
244 LIBCFS_CPT_ALLOC(lp, lnet_cpt_table(), cpt2, sizeof(*lp));
245
246 if (lp == NULL) {
247 rc = -ENOMEM;
248 lnet_net_lock(cpt);
249 goto out;
250 }
251
252 INIT_LIST_HEAD(&lp->lp_txq);
253 INIT_LIST_HEAD(&lp->lp_rtrq);
254 INIT_LIST_HEAD(&lp->lp_routes);
255
256 lp->lp_notify = 0;
257 lp->lp_notifylnd = 0;
258 lp->lp_notifying = 0;
259 lp->lp_alive_count = 0;
260 lp->lp_timestamp = 0;
261 lp->lp_alive = !lnet_peers_start_down(); /* 1 bit!! */
262 lp->lp_last_alive = cfs_time_current(); /* assumes alive */
263 lp->lp_last_query = 0; /* haven't asked NI yet */
264 lp->lp_ping_timestamp = 0;
265 lp->lp_ping_feats = LNET_PING_FEAT_INVAL;
266 lp->lp_nid = nid;
267 lp->lp_cpt = cpt2;
268 lp->lp_refcount = 2; /* 1 for caller; 1 for hash */
269 lp->lp_rtr_refcount = 0;
270
271 lnet_net_lock(cpt);
272
273 if (the_lnet.ln_shutdown) {
274 rc = -ESHUTDOWN;
275 goto out;
276 }
277
278 lp2 = lnet_find_peer_locked(ptable, nid);
279 if (lp2 != NULL) {
280 *lpp = lp2;
281 goto out;
282 }
283
284 lp->lp_ni = lnet_net2ni_locked(LNET_NIDNET(nid), cpt2);
285 if (lp->lp_ni == NULL) {
286 rc = -EHOSTUNREACH;
287 goto out;
288 }
289
290 lp->lp_txcredits =
291 lp->lp_mintxcredits = lp->lp_ni->ni_peertxcredits;
292 lp->lp_rtrcredits =
293 lp->lp_minrtrcredits = lnet_peer_buffer_credits(lp->lp_ni);
294
295 list_add_tail(&lp->lp_hashlist,
296 &ptable->pt_hash[lnet_nid2peerhash(nid)]);
297 ptable->pt_version++;
298 *lpp = lp;
299
300 return 0;
301 out:
302 if (lp != NULL)
303 list_add(&lp->lp_hashlist, &ptable->pt_deathrow);
304 ptable->pt_number--;
305 return rc;
306 }
307
308 void
lnet_debug_peer(lnet_nid_t nid)309 lnet_debug_peer(lnet_nid_t nid)
310 {
311 char *aliveness = "NA";
312 lnet_peer_t *lp;
313 int rc;
314 int cpt;
315
316 cpt = lnet_cpt_of_nid(nid);
317 lnet_net_lock(cpt);
318
319 rc = lnet_nid2peer_locked(&lp, nid, cpt);
320 if (rc != 0) {
321 lnet_net_unlock(cpt);
322 CDEBUG(D_WARNING, "No peer %s\n", libcfs_nid2str(nid));
323 return;
324 }
325
326 if (lnet_isrouter(lp) || lnet_peer_aliveness_enabled(lp))
327 aliveness = lp->lp_alive ? "up" : "down";
328
329 CDEBUG(D_WARNING, "%-24s %4d %5s %5d %5d %5d %5d %5d %ld\n",
330 libcfs_nid2str(lp->lp_nid), lp->lp_refcount,
331 aliveness, lp->lp_ni->ni_peertxcredits,
332 lp->lp_rtrcredits, lp->lp_minrtrcredits,
333 lp->lp_txcredits, lp->lp_mintxcredits, lp->lp_txqnob);
334
335 lnet_peer_decref_locked(lp);
336
337 lnet_net_unlock(cpt);
338 }
339