xref: /openbmc/qemu/net/colo-compare.c (revision 2bfe11c8)
1 /*
2  * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO)
3  * (a.k.a. Fault Tolerance or Continuous Replication)
4  *
5  * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
6  * Copyright (c) 2016 FUJITSU LIMITED
7  * Copyright (c) 2016 Intel Corporation
8  *
9  * Author: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
10  *
11  * This work is licensed under the terms of the GNU GPL, version 2 or
12  * later.  See the COPYING file in the top-level directory.
13  */
14 
15 #include "qemu/osdep.h"
16 #include "qemu/error-report.h"
17 #include "trace.h"
18 #include "qemu-common.h"
19 #include "qapi/qmp/qerror.h"
20 #include "qapi/error.h"
21 #include "net/net.h"
22 #include "net/eth.h"
23 #include "qom/object_interfaces.h"
24 #include "qemu/iov.h"
25 #include "qom/object.h"
26 #include "qemu/typedefs.h"
27 #include "net/queue.h"
28 #include "sysemu/char.h"
29 #include "qemu/sockets.h"
30 #include "qapi-visit.h"
31 #include "net/colo.h"
32 
33 #define TYPE_COLO_COMPARE "colo-compare"
34 #define COLO_COMPARE(obj) \
35     OBJECT_CHECK(CompareState, (obj), TYPE_COLO_COMPARE)
36 
37 #define COMPARE_READ_LEN_MAX NET_BUFSIZE
38 #define MAX_QUEUE_SIZE 1024
39 
40 /* TODO: Should be configurable */
41 #define REGULAR_PACKET_CHECK_MS 3000
42 
43 /*
44   + CompareState ++
45   |               |
46   +---------------+   +---------------+         +---------------+
47   |conn list      +--->conn           +--------->conn           |
48   +---------------+   +---------------+         +---------------+
49   |               |     |           |             |          |
50   +---------------+ +---v----+  +---v----+    +---v----+ +---v----+
51                     |primary |  |secondary    |primary | |secondary
52                     |packet  |  |packet  +    |packet  | |packet  +
53                     +--------+  +--------+    +--------+ +--------+
54                         |           |             |          |
55                     +---v----+  +---v----+    +---v----+ +---v----+
56                     |primary |  |secondary    |primary | |secondary
57                     |packet  |  |packet  +    |packet  | |packet  +
58                     +--------+  +--------+    +--------+ +--------+
59                         |           |             |          |
60                     +---v----+  +---v----+    +---v----+ +---v----+
61                     |primary |  |secondary    |primary | |secondary
62                     |packet  |  |packet  +    |packet  | |packet  +
63                     +--------+  +--------+    +--------+ +--------+
64 */
65 typedef struct CompareState {
66     Object parent;
67 
68     char *pri_indev;
69     char *sec_indev;
70     char *outdev;
71     CharDriverState *chr_pri_in;
72     CharDriverState *chr_sec_in;
73     CharDriverState *chr_out;
74     SocketReadState pri_rs;
75     SocketReadState sec_rs;
76 
77     /* connection list: the connections belonged to this NIC could be found
78      * in this list.
79      * element type: Connection
80      */
81     GQueue conn_list;
82     /* hashtable to save connection */
83     GHashTable *connection_track_table;
84     /* compare thread, a thread for each NIC */
85     QemuThread thread;
86     /* Timer used on the primary to find packets that are never matched */
87     QEMUTimer *timer;
88     QemuMutex timer_check_lock;
89 } CompareState;
90 
91 typedef struct CompareClass {
92     ObjectClass parent_class;
93 } CompareClass;
94 
95 typedef struct CompareChardevProps {
96     bool is_socket;
97 } CompareChardevProps;
98 
99 enum {
100     PRIMARY_IN = 0,
101     SECONDARY_IN,
102 };
103 
104 static int compare_chr_send(CharDriverState *out,
105                             const uint8_t *buf,
106                             uint32_t size);
107 
108 /*
109  * Return 0 on success, if return -1 means the pkt
110  * is unsupported(arp and ipv6) and will be sent later
111  */
112 static int packet_enqueue(CompareState *s, int mode)
113 {
114     ConnectionKey key;
115     Packet *pkt = NULL;
116     Connection *conn;
117 
118     if (mode == PRIMARY_IN) {
119         pkt = packet_new(s->pri_rs.buf, s->pri_rs.packet_len);
120     } else {
121         pkt = packet_new(s->sec_rs.buf, s->sec_rs.packet_len);
122     }
123 
124     if (parse_packet_early(pkt)) {
125         packet_destroy(pkt, NULL);
126         pkt = NULL;
127         return -1;
128     }
129     fill_connection_key(pkt, &key);
130 
131     conn = connection_get(s->connection_track_table,
132                           &key,
133                           &s->conn_list);
134 
135     if (!conn->processing) {
136         g_queue_push_tail(&s->conn_list, conn);
137         conn->processing = true;
138     }
139 
140     if (mode == PRIMARY_IN) {
141         if (g_queue_get_length(&conn->primary_list) <=
142                                MAX_QUEUE_SIZE) {
143             g_queue_push_tail(&conn->primary_list, pkt);
144         } else {
145             error_report("colo compare primary queue size too big,"
146                          "drop packet");
147         }
148     } else {
149         if (g_queue_get_length(&conn->secondary_list) <=
150                                MAX_QUEUE_SIZE) {
151             g_queue_push_tail(&conn->secondary_list, pkt);
152         } else {
153             error_report("colo compare secondary queue size too big,"
154                          "drop packet");
155         }
156     }
157 
158     return 0;
159 }
160 
161 /*
162  * The IP packets sent by primary and secondary
163  * will be compared in here
164  * TODO support ip fragment, Out-Of-Order
165  * return:    0  means packet same
166  *            > 0 || < 0 means packet different
167  */
168 static int colo_packet_compare(Packet *ppkt, Packet *spkt)
169 {
170     trace_colo_compare_ip_info(ppkt->size, inet_ntoa(ppkt->ip->ip_src),
171                                inet_ntoa(ppkt->ip->ip_dst), spkt->size,
172                                inet_ntoa(spkt->ip->ip_src),
173                                inet_ntoa(spkt->ip->ip_dst));
174 
175     if (ppkt->size == spkt->size) {
176         return memcmp(ppkt->data, spkt->data, spkt->size);
177     } else {
178         return -1;
179     }
180 }
181 
182 /*
183  * Called from the compare thread on the primary
184  * for compare tcp packet
185  * compare_tcp copied from Dr. David Alan Gilbert's branch
186  */
187 static int colo_packet_compare_tcp(Packet *spkt, Packet *ppkt)
188 {
189     struct tcphdr *ptcp, *stcp;
190     int res;
191     char *sdebug, *ddebug;
192 
193     trace_colo_compare_main("compare tcp");
194     if (ppkt->size != spkt->size) {
195         if (trace_event_get_state(TRACE_COLO_COMPARE_MISCOMPARE)) {
196             trace_colo_compare_main("pkt size not same");
197         }
198         return -1;
199     }
200 
201     ptcp = (struct tcphdr *)ppkt->transport_header;
202     stcp = (struct tcphdr *)spkt->transport_header;
203 
204     /*
205      * The 'identification' field in the IP header is *very* random
206      * it almost never matches.  Fudge this by ignoring differences in
207      * unfragmented packets; they'll normally sort themselves out if different
208      * anyway, and it should recover at the TCP level.
209      * An alternative would be to get both the primary and secondary to rewrite
210      * somehow; but that would need some sync traffic to sync the state
211      */
212     if (ntohs(ppkt->ip->ip_off) & IP_DF) {
213         spkt->ip->ip_id = ppkt->ip->ip_id;
214         /* and the sum will be different if the IDs were different */
215         spkt->ip->ip_sum = ppkt->ip->ip_sum;
216     }
217 
218     res = memcmp(ppkt->data + ETH_HLEN, spkt->data + ETH_HLEN,
219                 (spkt->size - ETH_HLEN));
220 
221     if (res != 0 && trace_event_get_state(TRACE_COLO_COMPARE_MISCOMPARE)) {
222         sdebug = strdup(inet_ntoa(ppkt->ip->ip_src));
223         ddebug = strdup(inet_ntoa(ppkt->ip->ip_dst));
224         fprintf(stderr, "%s: src/dst: %s/%s p: seq/ack=%u/%u"
225                 " s: seq/ack=%u/%u res=%d flags=%x/%x\n",
226                 __func__, sdebug, ddebug,
227                 (unsigned int)ntohl(ptcp->th_seq),
228                 (unsigned int)ntohl(ptcp->th_ack),
229                 (unsigned int)ntohl(stcp->th_seq),
230                 (unsigned int)ntohl(stcp->th_ack),
231                 res, ptcp->th_flags, stcp->th_flags);
232 
233         fprintf(stderr, "Primary len = %d\n", ppkt->size);
234         qemu_hexdump((char *)ppkt->data, stderr, "colo-compare", ppkt->size);
235         fprintf(stderr, "Secondary len = %d\n", spkt->size);
236         qemu_hexdump((char *)spkt->data, stderr, "colo-compare", spkt->size);
237 
238         g_free(sdebug);
239         g_free(ddebug);
240     }
241 
242     return res;
243 }
244 
245 /*
246  * Called from the compare thread on the primary
247  * for compare udp packet
248  */
249 static int colo_packet_compare_udp(Packet *spkt, Packet *ppkt)
250 {
251     int ret;
252 
253     trace_colo_compare_main("compare udp");
254     ret = colo_packet_compare(ppkt, spkt);
255 
256     if (ret) {
257         trace_colo_compare_udp_miscompare("primary pkt size", ppkt->size);
258         qemu_hexdump((char *)ppkt->data, stderr, "colo-compare", ppkt->size);
259         trace_colo_compare_udp_miscompare("Secondary pkt size", spkt->size);
260         qemu_hexdump((char *)spkt->data, stderr, "colo-compare", spkt->size);
261     }
262 
263     return ret;
264 }
265 
266 /*
267  * Called from the compare thread on the primary
268  * for compare icmp packet
269  */
270 static int colo_packet_compare_icmp(Packet *spkt, Packet *ppkt)
271 {
272     int network_length;
273 
274     trace_colo_compare_main("compare icmp");
275     network_length = ppkt->ip->ip_hl * 4;
276     if (ppkt->size != spkt->size ||
277         ppkt->size < network_length + ETH_HLEN) {
278         return -1;
279     }
280 
281     if (colo_packet_compare(ppkt, spkt)) {
282         trace_colo_compare_icmp_miscompare("primary pkt size",
283                                            ppkt->size);
284         qemu_hexdump((char *)ppkt->data, stderr, "colo-compare",
285                      ppkt->size);
286         trace_colo_compare_icmp_miscompare("Secondary pkt size",
287                                            spkt->size);
288         qemu_hexdump((char *)spkt->data, stderr, "colo-compare",
289                      spkt->size);
290         return -1;
291     } else {
292         return 0;
293     }
294 }
295 
296 /*
297  * Called from the compare thread on the primary
298  * for compare other packet
299  */
300 static int colo_packet_compare_other(Packet *spkt, Packet *ppkt)
301 {
302     trace_colo_compare_main("compare other");
303     trace_colo_compare_ip_info(ppkt->size, inet_ntoa(ppkt->ip->ip_src),
304                                inet_ntoa(ppkt->ip->ip_dst), spkt->size,
305                                inet_ntoa(spkt->ip->ip_src),
306                                inet_ntoa(spkt->ip->ip_dst));
307     return colo_packet_compare(ppkt, spkt);
308 }
309 
310 static int colo_old_packet_check_one(Packet *pkt, int64_t *check_time)
311 {
312     int64_t now = qemu_clock_get_ms(QEMU_CLOCK_HOST);
313 
314     if ((now - pkt->creation_ms) > (*check_time)) {
315         trace_colo_old_packet_check_found(pkt->creation_ms);
316         return 0;
317     } else {
318         return 1;
319     }
320 }
321 
322 static void colo_old_packet_check_one_conn(void *opaque,
323                                            void *user_data)
324 {
325     Connection *conn = opaque;
326     GList *result = NULL;
327     int64_t check_time = REGULAR_PACKET_CHECK_MS;
328 
329     result = g_queue_find_custom(&conn->primary_list,
330                                  &check_time,
331                                  (GCompareFunc)colo_old_packet_check_one);
332 
333     if (result) {
334         /* do checkpoint will flush old packet */
335         /* TODO: colo_notify_checkpoint();*/
336     }
337 }
338 
339 /*
340  * Look for old packets that the secondary hasn't matched,
341  * if we have some then we have to checkpoint to wake
342  * the secondary up.
343  */
344 static void colo_old_packet_check(void *opaque)
345 {
346     CompareState *s = opaque;
347 
348     g_queue_foreach(&s->conn_list, colo_old_packet_check_one_conn, NULL);
349 }
350 
351 /*
352  * Called from the compare thread on the primary
353  * for compare connection
354  */
355 static void colo_compare_connection(void *opaque, void *user_data)
356 {
357     CompareState *s = user_data;
358     Connection *conn = opaque;
359     Packet *pkt = NULL;
360     GList *result = NULL;
361     int ret;
362 
363     while (!g_queue_is_empty(&conn->primary_list) &&
364            !g_queue_is_empty(&conn->secondary_list)) {
365         qemu_mutex_lock(&s->timer_check_lock);
366         pkt = g_queue_pop_tail(&conn->primary_list);
367         qemu_mutex_unlock(&s->timer_check_lock);
368         switch (conn->ip_proto) {
369         case IPPROTO_TCP:
370             result = g_queue_find_custom(&conn->secondary_list,
371                      pkt, (GCompareFunc)colo_packet_compare_tcp);
372             break;
373         case IPPROTO_UDP:
374             result = g_queue_find_custom(&conn->secondary_list,
375                      pkt, (GCompareFunc)colo_packet_compare_udp);
376             break;
377         case IPPROTO_ICMP:
378             result = g_queue_find_custom(&conn->secondary_list,
379                      pkt, (GCompareFunc)colo_packet_compare_icmp);
380             break;
381         default:
382             result = g_queue_find_custom(&conn->secondary_list,
383                      pkt, (GCompareFunc)colo_packet_compare_other);
384             break;
385         }
386 
387         if (result) {
388             ret = compare_chr_send(s->chr_out, pkt->data, pkt->size);
389             if (ret < 0) {
390                 error_report("colo_send_primary_packet failed");
391             }
392             trace_colo_compare_main("packet same and release packet");
393             g_queue_remove(&conn->secondary_list, result->data);
394             packet_destroy(pkt, NULL);
395         } else {
396             /*
397              * If one packet arrive late, the secondary_list or
398              * primary_list will be empty, so we can't compare it
399              * until next comparison.
400              */
401             trace_colo_compare_main("packet different");
402             qemu_mutex_lock(&s->timer_check_lock);
403             g_queue_push_tail(&conn->primary_list, pkt);
404             qemu_mutex_unlock(&s->timer_check_lock);
405             /* TODO: colo_notify_checkpoint();*/
406             break;
407         }
408     }
409 }
410 
411 static int compare_chr_send(CharDriverState *out,
412                             const uint8_t *buf,
413                             uint32_t size)
414 {
415     int ret = 0;
416     uint32_t len = htonl(size);
417 
418     if (!size) {
419         return 0;
420     }
421 
422     ret = qemu_chr_fe_write_all(out, (uint8_t *)&len, sizeof(len));
423     if (ret != sizeof(len)) {
424         goto err;
425     }
426 
427     ret = qemu_chr_fe_write_all(out, (uint8_t *)buf, size);
428     if (ret != size) {
429         goto err;
430     }
431 
432     return 0;
433 
434 err:
435     return ret < 0 ? ret : -EIO;
436 }
437 
438 static int compare_chr_can_read(void *opaque)
439 {
440     return COMPARE_READ_LEN_MAX;
441 }
442 
443 /*
444  * Called from the main thread on the primary for packets
445  * arriving over the socket from the primary.
446  */
447 static void compare_pri_chr_in(void *opaque, const uint8_t *buf, int size)
448 {
449     CompareState *s = COLO_COMPARE(opaque);
450     int ret;
451 
452     ret = net_fill_rstate(&s->pri_rs, buf, size);
453     if (ret == -1) {
454         qemu_chr_add_handlers(s->chr_pri_in, NULL, NULL, NULL, NULL);
455         error_report("colo-compare primary_in error");
456     }
457 }
458 
459 /*
460  * Called from the main thread on the primary for packets
461  * arriving over the socket from the secondary.
462  */
463 static void compare_sec_chr_in(void *opaque, const uint8_t *buf, int size)
464 {
465     CompareState *s = COLO_COMPARE(opaque);
466     int ret;
467 
468     ret = net_fill_rstate(&s->sec_rs, buf, size);
469     if (ret == -1) {
470         qemu_chr_add_handlers(s->chr_sec_in, NULL, NULL, NULL, NULL);
471         error_report("colo-compare secondary_in error");
472     }
473 }
474 
475 static void *colo_compare_thread(void *opaque)
476 {
477     GMainContext *worker_context;
478     GMainLoop *compare_loop;
479     CompareState *s = opaque;
480 
481     worker_context = g_main_context_new();
482 
483     qemu_chr_add_handlers_full(s->chr_pri_in, compare_chr_can_read,
484                           compare_pri_chr_in, NULL, s, worker_context);
485     qemu_chr_add_handlers_full(s->chr_sec_in, compare_chr_can_read,
486                           compare_sec_chr_in, NULL, s, worker_context);
487 
488     compare_loop = g_main_loop_new(worker_context, FALSE);
489 
490     g_main_loop_run(compare_loop);
491 
492     g_main_loop_unref(compare_loop);
493     g_main_context_unref(worker_context);
494     return NULL;
495 }
496 
497 static char *compare_get_pri_indev(Object *obj, Error **errp)
498 {
499     CompareState *s = COLO_COMPARE(obj);
500 
501     return g_strdup(s->pri_indev);
502 }
503 
504 static void compare_set_pri_indev(Object *obj, const char *value, Error **errp)
505 {
506     CompareState *s = COLO_COMPARE(obj);
507 
508     g_free(s->pri_indev);
509     s->pri_indev = g_strdup(value);
510 }
511 
512 static char *compare_get_sec_indev(Object *obj, Error **errp)
513 {
514     CompareState *s = COLO_COMPARE(obj);
515 
516     return g_strdup(s->sec_indev);
517 }
518 
519 static void compare_set_sec_indev(Object *obj, const char *value, Error **errp)
520 {
521     CompareState *s = COLO_COMPARE(obj);
522 
523     g_free(s->sec_indev);
524     s->sec_indev = g_strdup(value);
525 }
526 
527 static char *compare_get_outdev(Object *obj, Error **errp)
528 {
529     CompareState *s = COLO_COMPARE(obj);
530 
531     return g_strdup(s->outdev);
532 }
533 
534 static void compare_set_outdev(Object *obj, const char *value, Error **errp)
535 {
536     CompareState *s = COLO_COMPARE(obj);
537 
538     g_free(s->outdev);
539     s->outdev = g_strdup(value);
540 }
541 
542 static void compare_pri_rs_finalize(SocketReadState *pri_rs)
543 {
544     CompareState *s = container_of(pri_rs, CompareState, pri_rs);
545 
546     if (packet_enqueue(s, PRIMARY_IN)) {
547         trace_colo_compare_main("primary: unsupported packet in");
548         compare_chr_send(s->chr_out, pri_rs->buf, pri_rs->packet_len);
549     } else {
550         /* compare connection */
551         g_queue_foreach(&s->conn_list, colo_compare_connection, s);
552     }
553 }
554 
555 static void compare_sec_rs_finalize(SocketReadState *sec_rs)
556 {
557     CompareState *s = container_of(sec_rs, CompareState, sec_rs);
558 
559     if (packet_enqueue(s, SECONDARY_IN)) {
560         trace_colo_compare_main("secondary: unsupported packet in");
561     } else {
562         /* compare connection */
563         g_queue_foreach(&s->conn_list, colo_compare_connection, s);
564     }
565 }
566 
567 static int compare_chardev_opts(void *opaque,
568                                 const char *name, const char *value,
569                                 Error **errp)
570 {
571     CompareChardevProps *props = opaque;
572 
573     if (strcmp(name, "backend") == 0 &&
574         strcmp(value, "socket") == 0) {
575         props->is_socket = true;
576         return 0;
577     } else if (strcmp(name, "host") == 0 ||
578               (strcmp(name, "port") == 0) ||
579               (strcmp(name, "server") == 0) ||
580               (strcmp(name, "wait") == 0) ||
581               (strcmp(name, "path") == 0)) {
582         return 0;
583     } else {
584         error_setg(errp,
585                    "COLO-compare does not support a chardev with option %s=%s",
586                    name, value);
587         return -1;
588     }
589 }
590 
591 /*
592  * Return 0 is success.
593  * Return 1 is failed.
594  */
595 static int find_and_check_chardev(CharDriverState **chr,
596                                   char *chr_name,
597                                   Error **errp)
598 {
599     CompareChardevProps props;
600 
601     *chr = qemu_chr_find(chr_name);
602     if (*chr == NULL) {
603         error_setg(errp, "Device '%s' not found",
604                    chr_name);
605         return 1;
606     }
607 
608     memset(&props, 0, sizeof(props));
609     if (qemu_opt_foreach((*chr)->opts, compare_chardev_opts, &props, errp)) {
610         return 1;
611     }
612 
613     if (!props.is_socket) {
614         error_setg(errp, "chardev \"%s\" is not a tcp socket",
615                    chr_name);
616         return 1;
617     }
618     return 0;
619 }
620 
621 /*
622  * Check old packet regularly so it can watch for any packets
623  * that the secondary hasn't produced equivalents of.
624  */
625 static void check_old_packet_regular(void *opaque)
626 {
627     CompareState *s = opaque;
628 
629     timer_mod(s->timer, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) +
630               REGULAR_PACKET_CHECK_MS);
631     /* if have old packet we will notify checkpoint */
632     /*
633      * TODO: Make timer handler run in compare thread
634      * like qemu_chr_add_handlers_full.
635      */
636     qemu_mutex_lock(&s->timer_check_lock);
637     colo_old_packet_check(s);
638     qemu_mutex_unlock(&s->timer_check_lock);
639 }
640 
641 /*
642  * Called from the main thread on the primary
643  * to setup colo-compare.
644  */
645 static void colo_compare_complete(UserCreatable *uc, Error **errp)
646 {
647     CompareState *s = COLO_COMPARE(uc);
648     char thread_name[64];
649     static int compare_id;
650 
651     if (!s->pri_indev || !s->sec_indev || !s->outdev) {
652         error_setg(errp, "colo compare needs 'primary_in' ,"
653                    "'secondary_in','outdev' property set");
654         return;
655     } else if (!strcmp(s->pri_indev, s->outdev) ||
656                !strcmp(s->sec_indev, s->outdev) ||
657                !strcmp(s->pri_indev, s->sec_indev)) {
658         error_setg(errp, "'indev' and 'outdev' could not be same "
659                    "for compare module");
660         return;
661     }
662 
663     if (find_and_check_chardev(&s->chr_pri_in, s->pri_indev, errp)) {
664         return;
665     }
666 
667     if (find_and_check_chardev(&s->chr_sec_in, s->sec_indev, errp)) {
668         return;
669     }
670 
671     if (find_and_check_chardev(&s->chr_out, s->outdev, errp)) {
672         return;
673     }
674 
675     qemu_chr_fe_claim_no_fail(s->chr_pri_in);
676 
677     qemu_chr_fe_claim_no_fail(s->chr_sec_in);
678 
679     qemu_chr_fe_claim_no_fail(s->chr_out);
680 
681     net_socket_rs_init(&s->pri_rs, compare_pri_rs_finalize);
682     net_socket_rs_init(&s->sec_rs, compare_sec_rs_finalize);
683 
684     g_queue_init(&s->conn_list);
685     qemu_mutex_init(&s->timer_check_lock);
686 
687     s->connection_track_table = g_hash_table_new_full(connection_key_hash,
688                                                       connection_key_equal,
689                                                       g_free,
690                                                       connection_destroy);
691 
692     sprintf(thread_name, "colo-compare %d", compare_id);
693     qemu_thread_create(&s->thread, thread_name,
694                        colo_compare_thread, s,
695                        QEMU_THREAD_JOINABLE);
696     compare_id++;
697 
698     /* A regular timer to kick any packets that the secondary doesn't match */
699     s->timer = timer_new_ms(QEMU_CLOCK_VIRTUAL, /* Only when guest runs */
700                             check_old_packet_regular, s);
701     timer_mod(s->timer, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) +
702                         REGULAR_PACKET_CHECK_MS);
703 
704     return;
705 }
706 
707 static void colo_compare_class_init(ObjectClass *oc, void *data)
708 {
709     UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
710 
711     ucc->complete = colo_compare_complete;
712 }
713 
714 static void colo_compare_init(Object *obj)
715 {
716     object_property_add_str(obj, "primary_in",
717                             compare_get_pri_indev, compare_set_pri_indev,
718                             NULL);
719     object_property_add_str(obj, "secondary_in",
720                             compare_get_sec_indev, compare_set_sec_indev,
721                             NULL);
722     object_property_add_str(obj, "outdev",
723                             compare_get_outdev, compare_set_outdev,
724                             NULL);
725 }
726 
727 static void colo_compare_finalize(Object *obj)
728 {
729     CompareState *s = COLO_COMPARE(obj);
730 
731     if (s->chr_pri_in) {
732         qemu_chr_add_handlers(s->chr_pri_in, NULL, NULL, NULL, NULL);
733         qemu_chr_fe_release(s->chr_pri_in);
734     }
735     if (s->chr_sec_in) {
736         qemu_chr_add_handlers(s->chr_sec_in, NULL, NULL, NULL, NULL);
737         qemu_chr_fe_release(s->chr_sec_in);
738     }
739     if (s->chr_out) {
740         qemu_chr_fe_release(s->chr_out);
741     }
742 
743     g_queue_free(&s->conn_list);
744 
745     if (qemu_thread_is_self(&s->thread)) {
746         /* compare connection */
747         g_queue_foreach(&s->conn_list, colo_compare_connection, s);
748         qemu_thread_join(&s->thread);
749     }
750 
751     if (s->timer) {
752         timer_del(s->timer);
753     }
754 
755     qemu_mutex_destroy(&s->timer_check_lock);
756 
757     g_free(s->pri_indev);
758     g_free(s->sec_indev);
759     g_free(s->outdev);
760 }
761 
762 static const TypeInfo colo_compare_info = {
763     .name = TYPE_COLO_COMPARE,
764     .parent = TYPE_OBJECT,
765     .instance_size = sizeof(CompareState),
766     .instance_init = colo_compare_init,
767     .instance_finalize = colo_compare_finalize,
768     .class_size = sizeof(CompareClass),
769     .class_init = colo_compare_class_init,
770     .interfaces = (InterfaceInfo[]) {
771         { TYPE_USER_CREATABLE },
772         { }
773     }
774 };
775 
776 static void register_types(void)
777 {
778     type_register_static(&colo_compare_info);
779 }
780 
781 type_init(register_types);
782