hammer2 - userland API / span work
[dragonfly.git] / sbin / hammer2 / msg_lnk.c
CommitLineData
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1/*
2 * Copyright (c) 2012 The DragonFly Project. All rights reserved.
3 *
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@dragonflybsd.org>
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
16 * distribution.
17 * 3. Neither the name of The DragonFly Project nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific, prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34/*
35 * LNK_SPAN PROTOCOL SUPPORT FUNCTIONS
36 *
37 * This code supports the LNK_SPAN protocol. Essentially all PFS's
38 * clients and services rendezvous with the userland hammer2 service and
39 * open LNK_SPAN transactions using a message header linkid of 0,
40 * registering any PFS's they have connectivity to with us.
41 *
42 * --
43 *
44 * Each registration maintains its own open LNK_SPAN message transaction.
45 * The SPANs are collected, aggregated, and retransmitted over available
46 * connections through the maintainance of additional LNK_SPAN message
47 * transactions on each link.
48 *
49 * The msgid for each active LNK_SPAN transaction we receive allows us to
50 * send a message to the target PFS (which might be one of many belonging
51 * to the same cluster), by specifying that msgid as the linkid in any
52 * message we send to the target PFS.
53 *
54 * Similarly the msgid we allocate for any LNK_SPAN transaction we transmit
55 * (and remember we will maintain multiple open LNK_SPAN transactions on
56 * each connection representing the topology span, so every node sees every
57 * other node as a separate open transaction). So, similarly the msgid for
58 * these active transactions which we initiated can be used by the other
59 * end to route messages through us to another node, ultimately winding up
60 * at the identified hammer2 PFS. We have to adjust the spanid in the message
61 * header at each hop to be representative of the outgoing LNK_SPAN we
62 * are forwarding the message through.
63 *
64 * --
65 *
66 * If we were to retransmit every LNK_SPAN transaction we receive it would
67 * create a huge mess, so we have to aggregate all received LNK_SPAN
68 * transactions, sort them by the fsid (the cluster) and sub-sort them by
69 * the pfs_fsid (individual nodes in the cluster), and only retransmit
7dc0f844 70 * (create outgoing transactions) for a subset of the nearest distance-hops
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71 * for each individual node.
72 *
73 * The higher level protocols can then issue transactions to the nodes making
74 * up a cluster to perform all actions required.
75 *
76 * --
77 *
78 * Since this is a large topology and a spanning tree protocol, links can
79 * go up and down all the time. Any time a link goes down its transaction
80 * is closed. The transaction has to be closed on both ends before we can
81 * delete (and potentially reuse) the related spanid. The LNK_SPAN being
82 * closed may have been propagated out to other connections and those related
83 * LNK_SPANs are also closed. Ultimately all routes via the lost LNK_SPAN
84 * go away, ultimately reaching all sources and all targets.
85 *
86 * Any messages in-transit using a route that goes away will be thrown away.
87 * Open transactions are only tracked at the two end-points. When a link
88 * failure propagates to an end-point the related open transactions lose
89 * their spanid and are automatically aborted.
90 *
91 * It is important to note that internal route nodes cannot just associate
92 * a lost LNK_SPAN transaction with another route to the same destination.
93 * Message transactions MUST be serialized and MUST be ordered. All messages
94 * for a transaction must run over the same route. So if the route used by
95 * an active transaction is lost, the related messages will be fully aborted
96 * and the higher protocol levels will retry as appropriate.
97 *
98 * It is also important to note that several paths to the same PFS can be
99 * propagated along the same link, which allows concurrency and even
100 * redundancy over several network interfaces or via different routes through
101 * the topology. Any given transaction will use only a single route but busy
102 * servers will often have hundreds of transactions active simultaniously,
103 * so having multiple active paths through the network topology for A<->B
104 * will improve performance.
105 *
106 * --
107 *
108 * Most protocols consolidate operations rather than simply relaying them.
109 * This is particularly true of LEAF protocols (such as strict HAMMER2
110 * clients), of which there can be millions connecting into the cluster at
111 * various points. The SPAN protocol is not used for these LEAF elements.
112 *
113 * Instead the primary service they connect to implements a proxy for the
114 * client protocols so the core topology only has to propagate a couple of
115 * LNK_SPANs and not millions. LNK_SPANs are meant to be used only for
116 * core master nodes and satellite slaves and cache nodes.
117 */
118
119#include "hammer2.h"
120
121/*
122 * RED-BLACK TREE DEFINITIONS
123 *
7dc0f844 124 * We need to track:
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125 *
126 * (1) shared fsid's (a cluster).
127 * (2) unique fsid's (a node in a cluster) <--- LNK_SPAN transactions.
128 *
129 * We need to aggegate all active LNK_SPANs, aggregate, and create our own
130 * outgoing LNK_SPAN transactions on each of our connections representing
131 * the aggregated state.
132 *
133 * h2span_connect - list of iocom connections who wish to receive SPAN
134 * propagation from other connections. Might contain
135 * a filter string. Only iocom's with an open
136 * LNK_CONN transactions are applicable for SPAN
137 * propagation.
138 *
139 * h2span_relay - List of links relayed (via SPAN). Essentially
140 * each relay structure represents a LNK_SPAN
141 * transaction that we initiated, verses h2span_link
142 * which is a LNK_SPAN transaction that we received.
143 *
144 * --
145 *
146 * h2span_cluster - Organizes the shared fsid's. One structure for
147 * each cluster.
148 *
149 * h2span_node - Organizes the nodes in a cluster. One structure
150 * for each unique {cluster,node}, aka {fsid, pfs_fsid}.
151 *
152 * h2span_link - Organizes all incoming and outgoing LNK_SPAN message
153 * transactions related to a node.
154 *
155 * One h2span_link structure for each incoming LNK_SPAN
156 * transaction. Links selected for propagation back
157 * out are also where the outgoing LNK_SPAN messages
158 * are indexed into (so we can propagate changes).
159 *
160 * The h2span_link's use a red-black tree to sort the
7dc0f844 161 * distance hop metric for the incoming LNK_SPAN. We
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162 * then select the top N for outgoing. When the
163 * topology changes the top N may also change and cause
164 * new outgoing LNK_SPAN transactions to be opened
165 * and less desireable ones to be closed, causing
166 * transactional aborts within the message flow in
167 * the process.
168 *
169 * Also note - All outgoing LNK_SPAN message transactions are also
170 * entered into a red-black tree for use by the routing
171 * function. This is handled by msg.c in the state
172 * code, not here.
173 */
174
175struct h2span_link;
176struct h2span_relay;
177TAILQ_HEAD(h2span_connect_queue, h2span_connect);
178TAILQ_HEAD(h2span_relay_queue, h2span_relay);
179
180RB_HEAD(h2span_cluster_tree, h2span_cluster);
181RB_HEAD(h2span_node_tree, h2span_node);
182RB_HEAD(h2span_link_tree, h2span_link);
183RB_HEAD(h2span_relay_tree, h2span_relay);
184
185/*
186 * Received LNK_CONN transaction enables SPAN protocol over connection.
187 * (may contain filter).
188 */
189struct h2span_connect {
190 TAILQ_ENTRY(h2span_connect) entry;
191 struct h2span_relay_tree tree;
192 hammer2_state_t *state;
193};
194
195/*
196 * All received LNK_SPANs are organized by cluster (pfs_clid),
197 * node (pfs_fsid), and link (received LNK_SPAN transaction).
198 */
199struct h2span_cluster {
200 RB_ENTRY(h2span_cluster) rbnode;
201 struct h2span_node_tree tree;
202 uuid_t pfs_clid; /* shared fsid */
203};
204
7dc0f844 205struct h2span_node {
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206 RB_ENTRY(h2span_node) rbnode;
207 struct h2span_link_tree tree;
208 struct h2span_cluster *cls;
209 uuid_t pfs_fsid; /* unique fsid */
81666e1b 210 char label[64];
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211};
212
213struct h2span_link {
214 RB_ENTRY(h2span_link) rbnode;
215 hammer2_state_t *state; /* state<->link */
216 struct h2span_node *node; /* related node */
7dc0f844 217 int32_t dist;
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218 struct h2span_relay_queue relayq; /* relay out */
219};
220
221/*
222 * Any LNK_SPAN transactions we receive which are relayed out other
223 * connections utilize this structure to track the LNK_SPAN transaction
224 * we initiate on the other connections, if selected for relay.
225 *
226 * In many respects this is the core of the protocol... actually figuring
227 * out what LNK_SPANs to relay. The spanid used for relaying is the
228 * address of the 'state' structure, which is why h2span_relay has to
229 * be entered into a RB-TREE based at h2span_connect (so we can look
230 * up the spanid to validate it).
231 */
232struct h2span_relay {
233 RB_ENTRY(h2span_relay) rbnode; /* from h2span_connect */
234 TAILQ_ENTRY(h2span_relay) entry; /* from link */
235 struct h2span_connect *conn;
236 hammer2_state_t *state; /* transmitted LNK_SPAN */
237 struct h2span_link *link; /* received LNK_SPAN */
238};
239
240
241typedef struct h2span_connect h2span_connect_t;
242typedef struct h2span_cluster h2span_cluster_t;
243typedef struct h2span_node h2span_node_t;
244typedef struct h2span_link h2span_link_t;
245typedef struct h2span_relay h2span_relay_t;
246
247static
248int
249h2span_cluster_cmp(h2span_cluster_t *cls1, h2span_cluster_t *cls2)
250{
251 return(uuid_compare(&cls1->pfs_clid, &cls2->pfs_clid, NULL));
252}
253
254static
255int
256h2span_node_cmp(h2span_node_t *node1, h2span_node_t *node2)
257{
258 return(uuid_compare(&node1->pfs_fsid, &node2->pfs_fsid, NULL));
259}
260
261static
262int
263h2span_link_cmp(h2span_link_t *link1, h2span_link_t *link2)
264{
7dc0f844 265 if (link1->dist < link2->dist)
8c280d5d 266 return(-1);
7dc0f844 267 if (link1->dist > link2->dist)
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268 return(1);
269 if ((intptr_t)link1 < (intptr_t)link2)
270 return(-1);
271 if ((intptr_t)link1 > (intptr_t)link2)
272 return(1);
273 return(0);
274}
275
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276/*
277 * Relay entries are sorted by node, subsorted by distance and link
278 * address (so we can match up the conn->tree relay topology with
279 * a node's link topology).
280 */
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281static
282int
283h2span_relay_cmp(h2span_relay_t *relay1, h2span_relay_t *relay2)
284{
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285 if ((intptr_t)relay1->link->node < (intptr_t)relay2->link->node)
286 return(-1);
287 if ((intptr_t)relay1->link->node > (intptr_t)relay2->link->node)
288 return(1);
289 if ((intptr_t)relay1->link->dist < (intptr_t)relay2->link->dist)
8c280d5d 290 return(-1);
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291 if ((intptr_t)relay1->link->dist > (intptr_t)relay2->link->dist)
292 return(1);
293 if ((intptr_t)relay1->link < (intptr_t)relay2->link)
294 return(-1);
295 if ((intptr_t)relay1->link > (intptr_t)relay2->link)
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296 return(1);
297 return(0);
298}
299
300RB_PROTOTYPE_STATIC(h2span_cluster_tree, h2span_cluster,
301 rbnode, h2span_cluster_cmp);
302RB_PROTOTYPE_STATIC(h2span_node_tree, h2span_node,
303 rbnode, h2span_node_cmp);
304RB_PROTOTYPE_STATIC(h2span_link_tree, h2span_link,
305 rbnode, h2span_link_cmp);
306RB_PROTOTYPE_STATIC(h2span_relay_tree, h2span_relay,
307 rbnode, h2span_relay_cmp);
308
309RB_GENERATE_STATIC(h2span_cluster_tree, h2span_cluster,
310 rbnode, h2span_cluster_cmp);
311RB_GENERATE_STATIC(h2span_node_tree, h2span_node,
312 rbnode, h2span_node_cmp);
313RB_GENERATE_STATIC(h2span_link_tree, h2span_link,
314 rbnode, h2span_link_cmp);
315RB_GENERATE_STATIC(h2span_relay_tree, h2span_relay,
316 rbnode, h2span_relay_cmp);
317
318/*
319 * Global mutex protects cluster_tree lookups.
320 */
321static pthread_mutex_t cluster_mtx;
322static struct h2span_cluster_tree cluster_tree = RB_INITIALIZER(cluster_tree);
323static struct h2span_connect_queue connq = TAILQ_HEAD_INITIALIZER(connq);
324
325static void hammer2_lnk_span(hammer2_state_t *state, hammer2_msg_t *msg);
326static void hammer2_lnk_conn(hammer2_state_t *state, hammer2_msg_t *msg);
7dc0f844 327static void hammer2_lnk_relay(hammer2_state_t *state, hammer2_msg_t *msg);
02454b3e 328static void hammer2_relay_scan(h2span_connect_t *conn, h2span_node_t *node);
7dc0f844 329static void hammer2_relay_delete(h2span_relay_t *relay);
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330
331/*
332 * Receive a HAMMER2_MSG_PROTO_LNK message. This only called for
333 * one-way and opening-transactions since state->func will be assigned
334 * in all other cases.
335 */
336void
337hammer2_msg_lnk(hammer2_iocom_t *iocom, hammer2_msg_t *msg)
338{
339 switch(msg->any.head.cmd & HAMMER2_MSGF_BASECMDMASK) {
340 case HAMMER2_LNK_CONN:
341 hammer2_lnk_conn(msg->state, msg);
342 break;
343 case HAMMER2_LNK_SPAN:
344 hammer2_lnk_span(msg->state, msg);
345 break;
346 default:
347 fprintf(stderr,
348 "MSG_PROTO_LNK: Unknown msg %08x\n", msg->any.head.cmd);
81666e1b 349 hammer2_msg_reply(iocom, msg, HAMMER2_MSG_ERR_NOSUPP);
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350 /* state invalid after reply */
351 break;
352 }
353}
354
355void
356hammer2_lnk_conn(hammer2_state_t *state, hammer2_msg_t *msg)
357{
358 h2span_connect_t *conn;
359 h2span_relay_t *relay;
360 char *alloc = NULL;
361
362 pthread_mutex_lock(&cluster_mtx);
363
364 /*
365 * On transaction start we allocate a new h2span_connect and
366 * acknowledge the request, leaving the transaction open.
7dc0f844 367 * We then relay priority-selected SPANs.
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368 */
369 if (msg->any.head.cmd & HAMMER2_MSGF_CREATE) {
370 state->func = hammer2_lnk_conn;
371
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372 fprintf(stderr, "LNK_CONN(%08x): %s/%s\n",
373 (uint32_t)msg->any.head.msgid,
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374 hammer2_uuid_to_str(&msg->any.lnk_conn.pfs_clid,
375 &alloc),
376 msg->any.lnk_conn.label);
377 free(alloc);
378
379 conn = hammer2_alloc(sizeof(*conn));
380
381 RB_INIT(&conn->tree);
382 conn->state = state;
383 state->any.conn = conn;
384 TAILQ_INSERT_TAIL(&connq, conn, entry);
385
8c280d5d 386 hammer2_msg_result(state->iocom, msg, 0);
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387
388 /*
389 * Span-synchronize all nodes with the new connection
390 */
391 hammer2_relay_scan(conn, NULL);
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392 }
393
394 /*
395 * On transaction terminate we clean out our h2span_connect
396 * and acknowledge the request, closing the transaction.
397 */
398 if (msg->any.head.cmd & HAMMER2_MSGF_DELETE) {
399 fprintf(stderr, "LNK_CONN: Terminated\n");
400 conn = state->any.conn;
401 assert(conn);
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402
403 /*
404 * Clean out all relays. This requires terminating each
405 * relay transaction.
406 */
8c280d5d 407 while ((relay = RB_ROOT(&conn->tree)) != NULL) {
7dc0f844 408 hammer2_relay_delete(relay);
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409 }
410
411 /*
412 * Clean out conn
413 */
414 conn->state = NULL;
415 msg->state->any.conn = NULL;
416 TAILQ_REMOVE(&connq, conn, entry);
417 hammer2_free(conn);
418
419 hammer2_msg_reply(state->iocom, msg, 0);
420 /* state invalid after reply */
421 }
422 pthread_mutex_unlock(&cluster_mtx);
423}
424
425void
426hammer2_lnk_span(hammer2_state_t *state, hammer2_msg_t *msg)
427{
428 h2span_cluster_t dummy_cls;
429 h2span_node_t dummy_node;
430 h2span_cluster_t *cls;
431 h2span_node_t *node;
432 h2span_link_t *slink;
433 h2span_relay_t *relay;
434 char *alloc = NULL;
435
436 pthread_mutex_lock(&cluster_mtx);
437
438 /*
439 * On transaction start we initialize the tracking infrastructure
440 */
441 if (msg->any.head.cmd & HAMMER2_MSGF_CREATE) {
442 state->func = hammer2_lnk_span;
443
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444 msg->any.lnk_span.label[sizeof(msg->any.lnk_span.label)-1] = 0;
445
446 fprintf(stderr, "LNK_SPAN: %s/%s dist=%d\n",
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447 hammer2_uuid_to_str(&msg->any.lnk_span.pfs_clid,
448 &alloc),
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449 msg->any.lnk_span.label,
450 msg->any.lnk_span.dist);
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451 free(alloc);
452
453 /*
454 * Find the cluster
455 */
456 dummy_cls.pfs_clid = msg->any.lnk_span.pfs_clid;
457 cls = RB_FIND(h2span_cluster_tree, &cluster_tree, &dummy_cls);
458 if (cls == NULL) {
459 cls = hammer2_alloc(sizeof(*cls));
460 cls->pfs_clid = msg->any.lnk_span.pfs_clid;
461 RB_INIT(&cls->tree);
462 RB_INSERT(h2span_cluster_tree, &cluster_tree, cls);
463 }
464
465 /*
466 * Find the node
467 */
468 dummy_node.pfs_fsid = msg->any.lnk_span.pfs_fsid;
469 node = RB_FIND(h2span_node_tree, &cls->tree, &dummy_node);
470 if (node == NULL) {
471 node = hammer2_alloc(sizeof(*node));
472 node->pfs_fsid = msg->any.lnk_span.pfs_fsid;
473 node->cls = cls;
474 RB_INIT(&node->tree);
475 RB_INSERT(h2span_node_tree, &cls->tree, node);
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476 snprintf(node->label, sizeof(node->label),
477 "%s", msg->any.lnk_span.label);
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478 }
479
480 /*
481 * Create the link
482 */
483 assert(state->any.link == NULL);
484 slink = hammer2_alloc(sizeof(*slink));
7dc0f844 485 TAILQ_INIT(&slink->relayq);
8c280d5d 486 slink->node = node;
7dc0f844 487 slink->dist = msg->any.lnk_span.dist;
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488 slink->state = state;
489 state->any.link = slink;
490 RB_INSERT(h2span_link_tree, &node->tree, slink);
491
02454b3e 492 hammer2_relay_scan(NULL, node);
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493 }
494
495 /*
496 * On transaction terminate we remove the tracking infrastructure.
497 */
498 if (msg->any.head.cmd & HAMMER2_MSGF_DELETE) {
499 slink = state->any.link;
500 assert(slink != NULL);
501 node = slink->node;
502 cls = node->cls;
503
504 /*
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505 * Clean out all relays. This requires terminating each
506 * relay transaction.
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507 */
508 while ((relay = TAILQ_FIRST(&slink->relayq)) != NULL) {
7dc0f844 509 hammer2_relay_delete(relay);
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510 }
511
512 /*
513 * Clean out the topology
514 */
515 RB_REMOVE(h2span_link_tree, &node->tree, slink);
516 if (RB_EMPTY(&node->tree)) {
517 RB_REMOVE(h2span_node_tree, &cls->tree, node);
518 if (RB_EMPTY(&cls->tree)) {
519 RB_REMOVE(h2span_cluster_tree,
520 &cluster_tree, cls);
521 hammer2_free(cls);
522 }
523 node->cls = NULL;
524 hammer2_free(node);
7dc0f844 525 node = NULL;
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526 }
527 state->any.link = NULL;
528 slink->state = NULL;
529 slink->node = NULL;
530 hammer2_free(slink);
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531
532 /*
533 * We have to terminate the transaction
534 */
535 hammer2_state_reply(state, 0);
536 /* state invalid after reply */
537
538 /*
539 * If the node still exists issue any required updates. If
540 * it doesn't then all related relays have already been
541 * removed and there's nothing left to do.
542 */
543 if (node)
02454b3e 544 hammer2_relay_scan(NULL, node);
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545 }
546
547 pthread_mutex_unlock(&cluster_mtx);
548}
549
550/*
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551 * Messages received on relay SPANs. These are open transactions so it is
552 * in fact possible for the other end to close the transaction.
553 *
554 * XXX MPRACE on state structure
555 */
556static void
557hammer2_lnk_relay(hammer2_state_t *state, hammer2_msg_t *msg)
558{
559 h2span_relay_t *relay;
560
561 if (msg->any.head.cmd & HAMMER2_MSGF_DELETE) {
562 pthread_mutex_lock(&cluster_mtx);
563 if ((relay = state->any.relay) != NULL) {
564 hammer2_relay_delete(relay);
565 } else {
566 hammer2_state_reply(state, 0);
567 }
568 pthread_mutex_unlock(&cluster_mtx);
569 }
570}
571
572/*
573 * Update relay transactions for SPANs.
574 *
575 * Called with cluster_mtx held.
576 */
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577static void hammer2_relay_scan_specific(h2span_node_t *node,
578 h2span_connect_t *conn);
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579
580static void
02454b3e 581hammer2_relay_scan(h2span_connect_t *conn, h2span_node_t *node)
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582{
583 h2span_cluster_t *cls;
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584
585 if (node) {
586 /*
587 * Iterate specific node
588 */
589 TAILQ_FOREACH(conn, &connq, entry)
02454b3e 590 hammer2_relay_scan_specific(node, conn);
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591 } else {
592 /*
02454b3e 593 * Full iteration.
7dc0f844 594 *
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595 * Iterate cluster ids, nodes, and either a specific connection
596 * or all connections.
7dc0f844 597 */
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598 RB_FOREACH(cls, h2span_cluster_tree, &cluster_tree) {
599 /*
600 * Iterate node ids
601 */
602 RB_FOREACH(node, h2span_node_tree, &cls->tree) {
603 /*
604 * Synchronize the node's link (received SPANs)
605 * with each connection's relays.
606 */
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607 if (conn) {
608 hammer2_relay_scan_specific(node, conn);
609 } else {
610 TAILQ_FOREACH(conn, &connq, entry) {
611 hammer2_relay_scan_specific(node,
612 conn);
613 }
614 assert(conn == NULL);
615 }
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616 }
617 }
618 }
619}
620
621/*
622 * Update the relay'd SPANs for this (node, conn).
623 *
624 * Iterate links and adjust relays to match. We only propagate the top link
625 * for now (XXX we want to propagate the top two).
626 *
627 * The hammer2_relay_scan_cmp() function locates the first relay element
628 * for any given node. The relay elements will be sub-sorted by dist.
8c280d5d 629 */
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630struct relay_scan_info {
631 h2span_node_t *node;
632 h2span_relay_t *relay;
633};
634
635static int
636hammer2_relay_scan_cmp(h2span_relay_t *relay, void *arg)
637{
638 struct relay_scan_info *info = arg;
639
640 if ((intptr_t)relay->link->node < (intptr_t)info->node)
641 return(-1);
642 if ((intptr_t)relay->link->node > (intptr_t)info->node)
643 return(1);
644 return(0);
645}
646
647static int
648hammer2_relay_scan_callback(h2span_relay_t *relay, void *arg)
649{
650 struct relay_scan_info *info = arg;
651
652 info->relay = relay;
653 return(-1);
654}
655
8c280d5d 656static void
02454b3e 657hammer2_relay_scan_specific(h2span_node_t *node, h2span_connect_t *conn)
8c280d5d 658{
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659 struct relay_scan_info info;
660 h2span_relay_t *relay;
661 h2span_relay_t *next_relay;
662 h2span_link_t *slink;
663 int count = 2;
664
665 info.node = node;
666 info.relay = NULL;
667
668 /*
669 * Locate the first related relay for the connection. relay will
670 * be NULL if there were none.
671 */
672 RB_SCAN(h2span_relay_tree, &conn->tree,
673 hammer2_relay_scan_cmp, hammer2_relay_scan_callback, &info);
674 relay = info.relay;
675
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676 if (DebugOpt > 8)
677 fprintf(stderr, "relay scan for connection %p\n", conn);
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678
679 /*
680 * Iterate the node's links (received SPANs) in distance order,
681 * lowest (best) dist first.
682 */
683 RB_FOREACH(slink, h2span_link_tree, &node->tree) {
684 /*
685 * PROPAGATE THE BEST RELAYS BY TRANSMITTING SPANs.
686 *
687 * Check for match against current best relay.
688 *
689 * A match failure means that the current best relay is not
690 * as good as the link, create a new relay for the link.
691 *
692 * (If some prior better link was removed it would have also
693 * removed the relay, so the relay can only match exactly or
694 * be worst).
695 */
696 info.relay = relay;
697 if (relay == NULL || relay->link != slink) {
698 hammer2_msg_t *msg;
699
700 assert(relay == NULL ||
02454b3e 701 relay->link->dist <= slink->dist);
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702 relay = hammer2_alloc(sizeof(*relay));
703 relay->conn = conn;
704 relay->link = slink;
705
706 msg = hammer2_msg_alloc(conn->state->iocom, 0,
707 HAMMER2_LNK_SPAN |
708 HAMMER2_MSGF_CREATE);
709 msg->any.lnk_span = slink->state->msg->any.lnk_span;
710 ++msg->any.lnk_span.dist; /* XXX add weighting */
711
712 hammer2_msg_write(conn->state->iocom, msg,
713 hammer2_lnk_relay, relay,
714 &relay->state);
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715 fprintf(stderr,
716 "RELAY SPAN ON CLS=%p NODE=%p FD %d state %p\n",
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717 node->cls, node,
718 conn->state->iocom->sock_fd, relay->state);
719
720 RB_INSERT(h2span_relay_tree, &conn->tree, relay);
721 TAILQ_INSERT_TAIL(&slink->relayq, relay, entry);
722 }
723
724 /*
725 * Iterate, figure out the next relay.
726 */
727 relay = RB_NEXT(h2span_relay_tree, &conn->tree, relay);
728 if (--count == 0) {
729 break;
730 continue;
731 }
732 }
733
734 /*
735 * Any remaining relay's belonging to this connection which match
736 * the node are in excess of the current aggregate spanning state
737 * and should be removed.
738 */
739 while (relay && relay->link->node == node) {
740 next_relay = RB_NEXT(h2span_relay_tree, &conn->tree, relay);
741 hammer2_relay_delete(relay);
742 relay = next_relay;
743 }
744}
745
746static
747void
748hammer2_relay_delete(h2span_relay_t *relay)
749{
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750 fprintf(stderr,
751 "RELAY DELETE ON CLS=%p NODE=%p FD %d STATE %p\n",
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752 relay->link->node->cls, relay->link->node,
753 relay->conn->state->iocom->sock_fd, relay->state);
754 fprintf(stderr, "RELAY TX %08x RX %08x\n", relay->state->txcmd, relay->state->rxcmd);
755
756 RB_REMOVE(h2span_relay_tree, &relay->conn->tree, relay);
757 TAILQ_REMOVE(&relay->link->relayq, relay, entry);
758
759 if (relay->state) {
760 relay->state->any.relay = NULL;
761 hammer2_state_reply(relay->state, 0);
762 /* state invalid after reply */
763 relay->state = NULL;
764 }
765 relay->conn = NULL;
766 relay->link = NULL;
767 hammer2_free(relay);
8c280d5d 768}
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769
770/*
771 * Dumps the spanning tree
772 */
773void
774shell_tree(hammer2_iocom_t *iocom, char *cmdbuf __unused)
775{
776 h2span_cluster_t *cls;
777 h2span_node_t *node;
778 h2span_link_t *slink;
779 char *uustr = NULL;
780
781 pthread_mutex_lock(&cluster_mtx);
782 RB_FOREACH(cls, h2span_cluster_tree, &cluster_tree) {
783 iocom_printf(iocom, "Cluster %s\n",
784 hammer2_uuid_to_str(&cls->pfs_clid, &uustr));
785 RB_FOREACH(node, h2span_node_tree, &cls->tree) {
786 iocom_printf(iocom, " Node %s (%s)\n",
787 hammer2_uuid_to_str(&node->pfs_fsid, &uustr),
788 node->label);
789 RB_FOREACH(slink, h2span_link_tree, &node->tree) {
790 iocom_printf(iocom, "\tLink dist=%d via %d\n",
791 slink->dist,
792 slink->state->iocom->sock_fd);
793 }
794 }
795 }
796 pthread_mutex_unlock(&cluster_mtx);
797 if (uustr)
798 free(uustr);
799#if 0
800 TAILQ_FOREACH(conn, &connq, entry) {
801 }
802#endif
803}