4 * Copyright IBM, Corp. 2008
7 * Anthony Liguori <aliguori@us.ibm.com>
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
12 * Contributions after 2012-01-13 are licensed under the terms of the
13 * GNU GPL, version 2 or (at your option) any later version.
16 #include "qemu-common.h"
17 #include "qemu/error-report.h"
18 #include "qemu/main-loop.h"
19 #include "migration/migration.h"
20 #include "migration/qemu-file.h"
21 #include "sysemu/sysemu.h"
22 #include "block/block.h"
23 #include "qapi/qmp/qerror.h"
24 #include "qemu/sockets.h"
26 #include "migration/block.h"
27 #include "qemu/thread.h"
28 #include "qmp-commands.h"
30 #include "qapi/util.h"
31 #include "qapi-event.h"
34 #define MAX_THROTTLE (32 << 20) /* Migration transfer speed throttling */
36 /* Amount of time to allocate to each "chunk" of bandwidth-throttled
38 #define BUFFER_DELAY 100
39 #define XFER_LIMIT_RATIO (1000 / BUFFER_DELAY)
41 /* Default compression thread count */
42 #define DEFAULT_MIGRATE_COMPRESS_THREAD_COUNT 8
43 /* Default decompression thread count, usually decompression is at
44 * least 4 times as fast as compression.*/
45 #define DEFAULT_MIGRATE_DECOMPRESS_THREAD_COUNT 2
46 /*0: means nocompress, 1: best speed, ... 9: best compress ratio */
47 #define DEFAULT_MIGRATE_COMPRESS_LEVEL 1
48 /* Define default autoconverge cpu throttle migration parameters */
49 #define DEFAULT_MIGRATE_X_CPU_THROTTLE_INITIAL 20
50 #define DEFAULT_MIGRATE_X_CPU_THROTTLE_INCREMENT 10
52 /* Migration XBZRLE default cache size */
53 #define DEFAULT_MIGRATE_CACHE_SIZE (64 * 1024 * 1024)
55 static NotifierList migration_state_notifiers
=
56 NOTIFIER_LIST_INITIALIZER(migration_state_notifiers
);
58 static bool deferred_incoming
;
61 * Current state of incoming postcopy; note this is not part of
62 * MigrationIncomingState since it's state is used during cleanup
63 * at the end as MIS is being freed.
65 static PostcopyState incoming_postcopy_state
;
67 /* When we add fault tolerance, we could have several
68 migrations at once. For now we don't need to add
69 dynamic creation of migration */
72 MigrationState
*migrate_get_current(void)
74 static MigrationState current_migration
= {
75 .state
= MIGRATION_STATUS_NONE
,
76 .bandwidth_limit
= MAX_THROTTLE
,
77 .xbzrle_cache_size
= DEFAULT_MIGRATE_CACHE_SIZE
,
79 .parameters
[MIGRATION_PARAMETER_COMPRESS_LEVEL
] =
80 DEFAULT_MIGRATE_COMPRESS_LEVEL
,
81 .parameters
[MIGRATION_PARAMETER_COMPRESS_THREADS
] =
82 DEFAULT_MIGRATE_COMPRESS_THREAD_COUNT
,
83 .parameters
[MIGRATION_PARAMETER_DECOMPRESS_THREADS
] =
84 DEFAULT_MIGRATE_DECOMPRESS_THREAD_COUNT
,
85 .parameters
[MIGRATION_PARAMETER_X_CPU_THROTTLE_INITIAL
] =
86 DEFAULT_MIGRATE_X_CPU_THROTTLE_INITIAL
,
87 .parameters
[MIGRATION_PARAMETER_X_CPU_THROTTLE_INCREMENT
] =
88 DEFAULT_MIGRATE_X_CPU_THROTTLE_INCREMENT
,
91 return ¤t_migration
;
95 static MigrationIncomingState
*mis_current
;
97 MigrationIncomingState
*migration_incoming_get_current(void)
102 MigrationIncomingState
*migration_incoming_state_new(QEMUFile
* f
)
104 mis_current
= g_new0(MigrationIncomingState
, 1);
105 mis_current
->from_src_file
= f
;
106 QLIST_INIT(&mis_current
->loadvm_handlers
);
107 qemu_mutex_init(&mis_current
->rp_mutex
);
108 qemu_event_init(&mis_current
->main_thread_load_event
, false);
113 void migration_incoming_state_destroy(void)
115 qemu_event_destroy(&mis_current
->main_thread_load_event
);
116 loadvm_free_handlers(mis_current
);
125 uint8_t runstate
[100];
130 static GlobalState global_state
;
132 int global_state_store(void)
134 if (!runstate_store((char *)global_state
.runstate
,
135 sizeof(global_state
.runstate
))) {
136 error_report("runstate name too big: %s", global_state
.runstate
);
137 trace_migrate_state_too_big();
143 void global_state_store_running(void)
145 const char *state
= RunState_lookup
[RUN_STATE_RUNNING
];
146 strncpy((char *)global_state
.runstate
,
147 state
, sizeof(global_state
.runstate
));
150 static bool global_state_received(void)
152 return global_state
.received
;
155 static RunState
global_state_get_runstate(void)
157 return global_state
.state
;
160 void global_state_set_optional(void)
162 global_state
.optional
= true;
165 static bool global_state_needed(void *opaque
)
167 GlobalState
*s
= opaque
;
168 char *runstate
= (char *)s
->runstate
;
170 /* If it is not optional, it is mandatory */
172 if (s
->optional
== false) {
176 /* If state is running or paused, it is not needed */
178 if (strcmp(runstate
, "running") == 0 ||
179 strcmp(runstate
, "paused") == 0) {
183 /* for any other state it is needed */
187 static int global_state_post_load(void *opaque
, int version_id
)
189 GlobalState
*s
= opaque
;
190 Error
*local_err
= NULL
;
192 char *runstate
= (char *)s
->runstate
;
195 trace_migrate_global_state_post_load(runstate
);
197 r
= qapi_enum_parse(RunState_lookup
, runstate
, RUN_STATE_MAX
,
202 error_report_err(local_err
);
211 static void global_state_pre_save(void *opaque
)
213 GlobalState
*s
= opaque
;
215 trace_migrate_global_state_pre_save((char *)s
->runstate
);
216 s
->size
= strlen((char *)s
->runstate
) + 1;
219 static const VMStateDescription vmstate_globalstate
= {
220 .name
= "globalstate",
222 .minimum_version_id
= 1,
223 .post_load
= global_state_post_load
,
224 .pre_save
= global_state_pre_save
,
225 .needed
= global_state_needed
,
226 .fields
= (VMStateField
[]) {
227 VMSTATE_UINT32(size
, GlobalState
),
228 VMSTATE_BUFFER(runstate
, GlobalState
),
229 VMSTATE_END_OF_LIST()
233 void register_global_state(void)
235 /* We would use it independently that we receive it */
236 strcpy((char *)&global_state
.runstate
, "");
237 global_state
.received
= false;
238 vmstate_register(NULL
, 0, &vmstate_globalstate
, &global_state
);
241 static void migrate_generate_event(int new_state
)
243 if (migrate_use_events()) {
244 qapi_event_send_migration(new_state
, &error_abort
);
249 * Called on -incoming with a defer: uri.
250 * The migration can be started later after any parameters have been
253 static void deferred_incoming_migration(Error
**errp
)
255 if (deferred_incoming
) {
256 error_setg(errp
, "Incoming migration already deferred");
258 deferred_incoming
= true;
261 void qemu_start_incoming_migration(const char *uri
, Error
**errp
)
265 qapi_event_send_migration(MIGRATION_STATUS_SETUP
, &error_abort
);
266 if (!strcmp(uri
, "defer")) {
267 deferred_incoming_migration(errp
);
268 } else if (strstart(uri
, "tcp:", &p
)) {
269 tcp_start_incoming_migration(p
, errp
);
271 } else if (strstart(uri
, "rdma:", &p
)) {
272 rdma_start_incoming_migration(p
, errp
);
275 } else if (strstart(uri
, "exec:", &p
)) {
276 exec_start_incoming_migration(p
, errp
);
277 } else if (strstart(uri
, "unix:", &p
)) {
278 unix_start_incoming_migration(p
, errp
);
279 } else if (strstart(uri
, "fd:", &p
)) {
280 fd_start_incoming_migration(p
, errp
);
283 error_setg(errp
, "unknown migration protocol: %s", uri
);
287 static void process_incoming_migration_co(void *opaque
)
289 QEMUFile
*f
= opaque
;
290 Error
*local_err
= NULL
;
293 migration_incoming_state_new(f
);
294 postcopy_state_set(POSTCOPY_INCOMING_NONE
);
295 migrate_generate_event(MIGRATION_STATUS_ACTIVE
);
296 ret
= qemu_loadvm_state(f
);
299 free_xbzrle_decoded_buf();
300 migration_incoming_state_destroy();
303 migrate_generate_event(MIGRATION_STATUS_FAILED
);
304 error_report("load of migration failed: %s", strerror(-ret
));
305 migrate_decompress_threads_join();
309 /* Make sure all file formats flush their mutable metadata */
310 bdrv_invalidate_cache_all(&local_err
);
312 migrate_generate_event(MIGRATION_STATUS_FAILED
);
313 error_report_err(local_err
);
314 migrate_decompress_threads_join();
319 * This must happen after all error conditions are dealt with and
320 * we're sure the VM is going to be running on this host.
322 qemu_announce_self();
324 /* If global state section was not received or we are in running
325 state, we need to obey autostart. Any other state is set with
328 if (!global_state_received() ||
329 global_state_get_runstate() == RUN_STATE_RUNNING
) {
333 runstate_set(RUN_STATE_PAUSED
);
336 runstate_set(global_state_get_runstate());
338 migrate_decompress_threads_join();
340 * This must happen after any state changes since as soon as an external
341 * observer sees this event they might start to prod at the VM assuming
344 migrate_generate_event(MIGRATION_STATUS_COMPLETED
);
347 void process_incoming_migration(QEMUFile
*f
)
349 Coroutine
*co
= qemu_coroutine_create(process_incoming_migration_co
);
350 int fd
= qemu_get_fd(f
);
353 migrate_decompress_threads_create();
354 qemu_set_nonblock(fd
);
355 qemu_coroutine_enter(co
, f
);
359 * Send a message on the return channel back to the source
362 void migrate_send_rp_message(MigrationIncomingState
*mis
,
363 enum mig_rp_message_type message_type
,
364 uint16_t len
, void *data
)
366 trace_migrate_send_rp_message((int)message_type
, len
);
367 qemu_mutex_lock(&mis
->rp_mutex
);
368 qemu_put_be16(mis
->to_src_file
, (unsigned int)message_type
);
369 qemu_put_be16(mis
->to_src_file
, len
);
370 qemu_put_buffer(mis
->to_src_file
, data
, len
);
371 qemu_fflush(mis
->to_src_file
);
372 qemu_mutex_unlock(&mis
->rp_mutex
);
376 * Send a 'SHUT' message on the return channel with the given value
377 * to indicate that we've finished with the RP. Non-0 value indicates
380 void migrate_send_rp_shut(MigrationIncomingState
*mis
,
385 buf
= cpu_to_be32(value
);
386 migrate_send_rp_message(mis
, MIG_RP_MSG_SHUT
, sizeof(buf
), &buf
);
390 * Send a 'PONG' message on the return channel with the given value
391 * (normally in response to a 'PING')
393 void migrate_send_rp_pong(MigrationIncomingState
*mis
,
398 buf
= cpu_to_be32(value
);
399 migrate_send_rp_message(mis
, MIG_RP_MSG_PONG
, sizeof(buf
), &buf
);
402 /* amount of nanoseconds we are willing to wait for migration to be down.
403 * the choice of nanoseconds is because it is the maximum resolution that
404 * get_clock() can achieve. It is an internal measure. All user-visible
405 * units must be in seconds */
406 static uint64_t max_downtime
= 300000000;
408 uint64_t migrate_max_downtime(void)
413 MigrationCapabilityStatusList
*qmp_query_migrate_capabilities(Error
**errp
)
415 MigrationCapabilityStatusList
*head
= NULL
;
416 MigrationCapabilityStatusList
*caps
;
417 MigrationState
*s
= migrate_get_current();
420 caps
= NULL
; /* silence compiler warning */
421 for (i
= 0; i
< MIGRATION_CAPABILITY_MAX
; i
++) {
423 head
= g_malloc0(sizeof(*caps
));
426 caps
->next
= g_malloc0(sizeof(*caps
));
430 g_malloc(sizeof(*caps
->value
));
431 caps
->value
->capability
= i
;
432 caps
->value
->state
= s
->enabled_capabilities
[i
];
438 MigrationParameters
*qmp_query_migrate_parameters(Error
**errp
)
440 MigrationParameters
*params
;
441 MigrationState
*s
= migrate_get_current();
443 params
= g_malloc0(sizeof(*params
));
444 params
->compress_level
= s
->parameters
[MIGRATION_PARAMETER_COMPRESS_LEVEL
];
445 params
->compress_threads
=
446 s
->parameters
[MIGRATION_PARAMETER_COMPRESS_THREADS
];
447 params
->decompress_threads
=
448 s
->parameters
[MIGRATION_PARAMETER_DECOMPRESS_THREADS
];
449 params
->x_cpu_throttle_initial
=
450 s
->parameters
[MIGRATION_PARAMETER_X_CPU_THROTTLE_INITIAL
];
451 params
->x_cpu_throttle_increment
=
452 s
->parameters
[MIGRATION_PARAMETER_X_CPU_THROTTLE_INCREMENT
];
458 * Return true if we're already in the middle of a migration
459 * (i.e. any of the active or setup states)
461 static bool migration_is_setup_or_active(int state
)
464 case MIGRATION_STATUS_ACTIVE
:
465 case MIGRATION_STATUS_SETUP
:
474 static void get_xbzrle_cache_stats(MigrationInfo
*info
)
476 if (migrate_use_xbzrle()) {
477 info
->has_xbzrle_cache
= true;
478 info
->xbzrle_cache
= g_malloc0(sizeof(*info
->xbzrle_cache
));
479 info
->xbzrle_cache
->cache_size
= migrate_xbzrle_cache_size();
480 info
->xbzrle_cache
->bytes
= xbzrle_mig_bytes_transferred();
481 info
->xbzrle_cache
->pages
= xbzrle_mig_pages_transferred();
482 info
->xbzrle_cache
->cache_miss
= xbzrle_mig_pages_cache_miss();
483 info
->xbzrle_cache
->cache_miss_rate
= xbzrle_mig_cache_miss_rate();
484 info
->xbzrle_cache
->overflow
= xbzrle_mig_pages_overflow();
488 MigrationInfo
*qmp_query_migrate(Error
**errp
)
490 MigrationInfo
*info
= g_malloc0(sizeof(*info
));
491 MigrationState
*s
= migrate_get_current();
494 case MIGRATION_STATUS_NONE
:
495 /* no migration has happened ever */
497 case MIGRATION_STATUS_SETUP
:
498 info
->has_status
= true;
499 info
->has_total_time
= false;
501 case MIGRATION_STATUS_ACTIVE
:
502 case MIGRATION_STATUS_CANCELLING
:
503 info
->has_status
= true;
504 info
->has_total_time
= true;
505 info
->total_time
= qemu_clock_get_ms(QEMU_CLOCK_REALTIME
)
507 info
->has_expected_downtime
= true;
508 info
->expected_downtime
= s
->expected_downtime
;
509 info
->has_setup_time
= true;
510 info
->setup_time
= s
->setup_time
;
512 info
->has_ram
= true;
513 info
->ram
= g_malloc0(sizeof(*info
->ram
));
514 info
->ram
->transferred
= ram_bytes_transferred();
515 info
->ram
->remaining
= ram_bytes_remaining();
516 info
->ram
->total
= ram_bytes_total();
517 info
->ram
->duplicate
= dup_mig_pages_transferred();
518 info
->ram
->skipped
= skipped_mig_pages_transferred();
519 info
->ram
->normal
= norm_mig_pages_transferred();
520 info
->ram
->normal_bytes
= norm_mig_bytes_transferred();
521 info
->ram
->dirty_pages_rate
= s
->dirty_pages_rate
;
522 info
->ram
->mbps
= s
->mbps
;
523 info
->ram
->dirty_sync_count
= s
->dirty_sync_count
;
525 if (blk_mig_active()) {
526 info
->has_disk
= true;
527 info
->disk
= g_malloc0(sizeof(*info
->disk
));
528 info
->disk
->transferred
= blk_mig_bytes_transferred();
529 info
->disk
->remaining
= blk_mig_bytes_remaining();
530 info
->disk
->total
= blk_mig_bytes_total();
533 if (cpu_throttle_active()) {
534 info
->has_x_cpu_throttle_percentage
= true;
535 info
->x_cpu_throttle_percentage
= cpu_throttle_get_percentage();
538 get_xbzrle_cache_stats(info
);
540 case MIGRATION_STATUS_COMPLETED
:
541 get_xbzrle_cache_stats(info
);
543 info
->has_status
= true;
544 info
->has_total_time
= true;
545 info
->total_time
= s
->total_time
;
546 info
->has_downtime
= true;
547 info
->downtime
= s
->downtime
;
548 info
->has_setup_time
= true;
549 info
->setup_time
= s
->setup_time
;
551 info
->has_ram
= true;
552 info
->ram
= g_malloc0(sizeof(*info
->ram
));
553 info
->ram
->transferred
= ram_bytes_transferred();
554 info
->ram
->remaining
= 0;
555 info
->ram
->total
= ram_bytes_total();
556 info
->ram
->duplicate
= dup_mig_pages_transferred();
557 info
->ram
->skipped
= skipped_mig_pages_transferred();
558 info
->ram
->normal
= norm_mig_pages_transferred();
559 info
->ram
->normal_bytes
= norm_mig_bytes_transferred();
560 info
->ram
->mbps
= s
->mbps
;
561 info
->ram
->dirty_sync_count
= s
->dirty_sync_count
;
563 case MIGRATION_STATUS_FAILED
:
564 info
->has_status
= true;
566 case MIGRATION_STATUS_CANCELLED
:
567 info
->has_status
= true;
570 info
->status
= s
->state
;
575 void qmp_migrate_set_capabilities(MigrationCapabilityStatusList
*params
,
578 MigrationState
*s
= migrate_get_current();
579 MigrationCapabilityStatusList
*cap
;
581 if (migration_is_setup_or_active(s
->state
)) {
582 error_setg(errp
, QERR_MIGRATION_ACTIVE
);
586 for (cap
= params
; cap
; cap
= cap
->next
) {
587 s
->enabled_capabilities
[cap
->value
->capability
] = cap
->value
->state
;
590 if (migrate_postcopy_ram()) {
591 if (migrate_use_compression()) {
592 /* The decompression threads asynchronously write into RAM
593 * rather than use the atomic copies needed to avoid
594 * userfaulting. It should be possible to fix the decompression
595 * threads for compatibility in future.
597 error_report("Postcopy is not currently compatible with "
599 s
->enabled_capabilities
[MIGRATION_CAPABILITY_X_POSTCOPY_RAM
] =
605 void qmp_migrate_set_parameters(bool has_compress_level
,
606 int64_t compress_level
,
607 bool has_compress_threads
,
608 int64_t compress_threads
,
609 bool has_decompress_threads
,
610 int64_t decompress_threads
,
611 bool has_x_cpu_throttle_initial
,
612 int64_t x_cpu_throttle_initial
,
613 bool has_x_cpu_throttle_increment
,
614 int64_t x_cpu_throttle_increment
, Error
**errp
)
616 MigrationState
*s
= migrate_get_current();
618 if (has_compress_level
&& (compress_level
< 0 || compress_level
> 9)) {
619 error_setg(errp
, QERR_INVALID_PARAMETER_VALUE
, "compress_level",
620 "is invalid, it should be in the range of 0 to 9");
623 if (has_compress_threads
&&
624 (compress_threads
< 1 || compress_threads
> 255)) {
625 error_setg(errp
, QERR_INVALID_PARAMETER_VALUE
,
627 "is invalid, it should be in the range of 1 to 255");
630 if (has_decompress_threads
&&
631 (decompress_threads
< 1 || decompress_threads
> 255)) {
632 error_setg(errp
, QERR_INVALID_PARAMETER_VALUE
,
633 "decompress_threads",
634 "is invalid, it should be in the range of 1 to 255");
637 if (has_x_cpu_throttle_initial
&&
638 (x_cpu_throttle_initial
< 1 || x_cpu_throttle_initial
> 99)) {
639 error_setg(errp
, QERR_INVALID_PARAMETER_VALUE
,
640 "x_cpu_throttle_initial",
641 "an integer in the range of 1 to 99");
643 if (has_x_cpu_throttle_increment
&&
644 (x_cpu_throttle_increment
< 1 || x_cpu_throttle_increment
> 99)) {
645 error_setg(errp
, QERR_INVALID_PARAMETER_VALUE
,
646 "x_cpu_throttle_increment",
647 "an integer in the range of 1 to 99");
650 if (has_compress_level
) {
651 s
->parameters
[MIGRATION_PARAMETER_COMPRESS_LEVEL
] = compress_level
;
653 if (has_compress_threads
) {
654 s
->parameters
[MIGRATION_PARAMETER_COMPRESS_THREADS
] = compress_threads
;
656 if (has_decompress_threads
) {
657 s
->parameters
[MIGRATION_PARAMETER_DECOMPRESS_THREADS
] =
660 if (has_x_cpu_throttle_initial
) {
661 s
->parameters
[MIGRATION_PARAMETER_X_CPU_THROTTLE_INITIAL
] =
662 x_cpu_throttle_initial
;
665 if (has_x_cpu_throttle_increment
) {
666 s
->parameters
[MIGRATION_PARAMETER_X_CPU_THROTTLE_INCREMENT
] =
667 x_cpu_throttle_increment
;
671 void qmp_migrate_start_postcopy(Error
**errp
)
673 MigrationState
*s
= migrate_get_current();
675 if (!migrate_postcopy_ram()) {
676 error_setg(errp
, "Enable postcopy with migration_set_capability before"
677 " the start of migration");
681 if (s
->state
== MIGRATION_STATUS_NONE
) {
682 error_setg(errp
, "Postcopy must be started after migration has been"
687 * we don't error if migration has finished since that would be racy
688 * with issuing this command.
690 atomic_set(&s
->start_postcopy
, true);
693 /* shared migration helpers */
695 static void migrate_set_state(MigrationState
*s
, int old_state
, int new_state
)
697 if (atomic_cmpxchg(&s
->state
, old_state
, new_state
) == old_state
) {
698 trace_migrate_set_state(new_state
);
699 migrate_generate_event(new_state
);
703 static void migrate_fd_cleanup(void *opaque
)
705 MigrationState
*s
= opaque
;
707 qemu_bh_delete(s
->cleanup_bh
);
708 s
->cleanup_bh
= NULL
;
711 trace_migrate_fd_cleanup();
712 qemu_mutex_unlock_iothread();
713 qemu_thread_join(&s
->thread
);
714 qemu_mutex_lock_iothread();
716 migrate_compress_threads_join();
717 qemu_fclose(s
->file
);
721 assert(s
->state
!= MIGRATION_STATUS_ACTIVE
);
723 if (s
->state
== MIGRATION_STATUS_CANCELLING
) {
724 migrate_set_state(s
, MIGRATION_STATUS_CANCELLING
,
725 MIGRATION_STATUS_CANCELLED
);
728 notifier_list_notify(&migration_state_notifiers
, s
);
731 void migrate_fd_error(MigrationState
*s
)
733 trace_migrate_fd_error();
734 assert(s
->file
== NULL
);
735 migrate_set_state(s
, MIGRATION_STATUS_SETUP
, MIGRATION_STATUS_FAILED
);
736 notifier_list_notify(&migration_state_notifiers
, s
);
739 static void migrate_fd_cancel(MigrationState
*s
)
742 QEMUFile
*f
= migrate_get_current()->file
;
743 trace_migrate_fd_cancel();
745 if (s
->rp_state
.from_dst_file
) {
746 /* shutdown the rp socket, so causing the rp thread to shutdown */
747 qemu_file_shutdown(s
->rp_state
.from_dst_file
);
751 old_state
= s
->state
;
752 if (!migration_is_setup_or_active(old_state
)) {
755 migrate_set_state(s
, old_state
, MIGRATION_STATUS_CANCELLING
);
756 } while (s
->state
!= MIGRATION_STATUS_CANCELLING
);
759 * If we're unlucky the migration code might be stuck somewhere in a
760 * send/write while the network has failed and is waiting to timeout;
761 * if we've got shutdown(2) available then we can force it to quit.
762 * The outgoing qemu file gets closed in migrate_fd_cleanup that is
763 * called in a bh, so there is no race against this cancel.
765 if (s
->state
== MIGRATION_STATUS_CANCELLING
&& f
) {
766 qemu_file_shutdown(f
);
770 void add_migration_state_change_notifier(Notifier
*notify
)
772 notifier_list_add(&migration_state_notifiers
, notify
);
775 void remove_migration_state_change_notifier(Notifier
*notify
)
777 notifier_remove(notify
);
780 bool migration_in_setup(MigrationState
*s
)
782 return s
->state
== MIGRATION_STATUS_SETUP
;
785 bool migration_has_finished(MigrationState
*s
)
787 return s
->state
== MIGRATION_STATUS_COMPLETED
;
790 bool migration_has_failed(MigrationState
*s
)
792 return (s
->state
== MIGRATION_STATUS_CANCELLED
||
793 s
->state
== MIGRATION_STATUS_FAILED
);
796 MigrationState
*migrate_init(const MigrationParams
*params
)
798 MigrationState
*s
= migrate_get_current();
799 int64_t bandwidth_limit
= s
->bandwidth_limit
;
800 bool enabled_capabilities
[MIGRATION_CAPABILITY_MAX
];
801 int64_t xbzrle_cache_size
= s
->xbzrle_cache_size
;
802 int compress_level
= s
->parameters
[MIGRATION_PARAMETER_COMPRESS_LEVEL
];
803 int compress_thread_count
=
804 s
->parameters
[MIGRATION_PARAMETER_COMPRESS_THREADS
];
805 int decompress_thread_count
=
806 s
->parameters
[MIGRATION_PARAMETER_DECOMPRESS_THREADS
];
807 int x_cpu_throttle_initial
=
808 s
->parameters
[MIGRATION_PARAMETER_X_CPU_THROTTLE_INITIAL
];
809 int x_cpu_throttle_increment
=
810 s
->parameters
[MIGRATION_PARAMETER_X_CPU_THROTTLE_INCREMENT
];
812 memcpy(enabled_capabilities
, s
->enabled_capabilities
,
813 sizeof(enabled_capabilities
));
815 memset(s
, 0, sizeof(*s
));
817 memcpy(s
->enabled_capabilities
, enabled_capabilities
,
818 sizeof(enabled_capabilities
));
819 s
->xbzrle_cache_size
= xbzrle_cache_size
;
821 s
->parameters
[MIGRATION_PARAMETER_COMPRESS_LEVEL
] = compress_level
;
822 s
->parameters
[MIGRATION_PARAMETER_COMPRESS_THREADS
] =
823 compress_thread_count
;
824 s
->parameters
[MIGRATION_PARAMETER_DECOMPRESS_THREADS
] =
825 decompress_thread_count
;
826 s
->parameters
[MIGRATION_PARAMETER_X_CPU_THROTTLE_INITIAL
] =
827 x_cpu_throttle_initial
;
828 s
->parameters
[MIGRATION_PARAMETER_X_CPU_THROTTLE_INCREMENT
] =
829 x_cpu_throttle_increment
;
830 s
->bandwidth_limit
= bandwidth_limit
;
831 migrate_set_state(s
, MIGRATION_STATUS_NONE
, MIGRATION_STATUS_SETUP
);
833 s
->total_time
= qemu_clock_get_ms(QEMU_CLOCK_REALTIME
);
837 static GSList
*migration_blockers
;
839 void migrate_add_blocker(Error
*reason
)
841 migration_blockers
= g_slist_prepend(migration_blockers
, reason
);
844 void migrate_del_blocker(Error
*reason
)
846 migration_blockers
= g_slist_remove(migration_blockers
, reason
);
849 void qmp_migrate_incoming(const char *uri
, Error
**errp
)
851 Error
*local_err
= NULL
;
852 static bool once
= true;
854 if (!deferred_incoming
) {
855 error_setg(errp
, "For use with '-incoming defer'");
859 error_setg(errp
, "The incoming migration has already been started");
862 qemu_start_incoming_migration(uri
, &local_err
);
865 error_propagate(errp
, local_err
);
872 void qmp_migrate(const char *uri
, bool has_blk
, bool blk
,
873 bool has_inc
, bool inc
, bool has_detach
, bool detach
,
876 Error
*local_err
= NULL
;
877 MigrationState
*s
= migrate_get_current();
878 MigrationParams params
;
881 params
.blk
= has_blk
&& blk
;
882 params
.shared
= has_inc
&& inc
;
884 if (migration_is_setup_or_active(s
->state
) ||
885 s
->state
== MIGRATION_STATUS_CANCELLING
) {
886 error_setg(errp
, QERR_MIGRATION_ACTIVE
);
889 if (runstate_check(RUN_STATE_INMIGRATE
)) {
890 error_setg(errp
, "Guest is waiting for an incoming migration");
894 if (qemu_savevm_state_blocked(errp
)) {
898 if (migration_blockers
) {
899 *errp
= error_copy(migration_blockers
->data
);
903 /* We are starting a new migration, so we want to start in a clean
904 state. This change is only needed if previous migration
905 failed/was cancelled. We don't use migrate_set_state() because
906 we are setting the initial state, not changing it. */
907 s
->state
= MIGRATION_STATUS_NONE
;
909 s
= migrate_init(¶ms
);
911 if (strstart(uri
, "tcp:", &p
)) {
912 tcp_start_outgoing_migration(s
, p
, &local_err
);
914 } else if (strstart(uri
, "rdma:", &p
)) {
915 rdma_start_outgoing_migration(s
, p
, &local_err
);
918 } else if (strstart(uri
, "exec:", &p
)) {
919 exec_start_outgoing_migration(s
, p
, &local_err
);
920 } else if (strstart(uri
, "unix:", &p
)) {
921 unix_start_outgoing_migration(s
, p
, &local_err
);
922 } else if (strstart(uri
, "fd:", &p
)) {
923 fd_start_outgoing_migration(s
, p
, &local_err
);
926 error_setg(errp
, QERR_INVALID_PARAMETER_VALUE
, "uri",
927 "a valid migration protocol");
928 migrate_set_state(s
, MIGRATION_STATUS_SETUP
, MIGRATION_STATUS_FAILED
);
934 error_propagate(errp
, local_err
);
939 void qmp_migrate_cancel(Error
**errp
)
941 migrate_fd_cancel(migrate_get_current());
944 void qmp_migrate_set_cache_size(int64_t value
, Error
**errp
)
946 MigrationState
*s
= migrate_get_current();
949 /* Check for truncation */
950 if (value
!= (size_t)value
) {
951 error_setg(errp
, QERR_INVALID_PARAMETER_VALUE
, "cache size",
952 "exceeding address space");
956 /* Cache should not be larger than guest ram size */
957 if (value
> ram_bytes_total()) {
958 error_setg(errp
, QERR_INVALID_PARAMETER_VALUE
, "cache size",
959 "exceeds guest ram size ");
963 new_size
= xbzrle_cache_resize(value
);
965 error_setg(errp
, QERR_INVALID_PARAMETER_VALUE
, "cache size",
966 "is smaller than page size");
970 s
->xbzrle_cache_size
= new_size
;
973 int64_t qmp_query_migrate_cache_size(Error
**errp
)
975 return migrate_xbzrle_cache_size();
978 void qmp_migrate_set_speed(int64_t value
, Error
**errp
)
985 if (value
> SIZE_MAX
) {
989 s
= migrate_get_current();
990 s
->bandwidth_limit
= value
;
992 qemu_file_set_rate_limit(s
->file
, s
->bandwidth_limit
/ XFER_LIMIT_RATIO
);
996 void qmp_migrate_set_downtime(double value
, Error
**errp
)
999 value
= MAX(0, MIN(UINT64_MAX
, value
));
1000 max_downtime
= (uint64_t)value
;
1003 bool migrate_postcopy_ram(void)
1007 s
= migrate_get_current();
1009 return s
->enabled_capabilities
[MIGRATION_CAPABILITY_X_POSTCOPY_RAM
];
1012 bool migrate_auto_converge(void)
1016 s
= migrate_get_current();
1018 return s
->enabled_capabilities
[MIGRATION_CAPABILITY_AUTO_CONVERGE
];
1021 bool migrate_zero_blocks(void)
1025 s
= migrate_get_current();
1027 return s
->enabled_capabilities
[MIGRATION_CAPABILITY_ZERO_BLOCKS
];
1030 bool migrate_use_compression(void)
1034 s
= migrate_get_current();
1036 return s
->enabled_capabilities
[MIGRATION_CAPABILITY_COMPRESS
];
1039 int migrate_compress_level(void)
1043 s
= migrate_get_current();
1045 return s
->parameters
[MIGRATION_PARAMETER_COMPRESS_LEVEL
];
1048 int migrate_compress_threads(void)
1052 s
= migrate_get_current();
1054 return s
->parameters
[MIGRATION_PARAMETER_COMPRESS_THREADS
];
1057 int migrate_decompress_threads(void)
1061 s
= migrate_get_current();
1063 return s
->parameters
[MIGRATION_PARAMETER_DECOMPRESS_THREADS
];
1066 bool migrate_use_events(void)
1070 s
= migrate_get_current();
1072 return s
->enabled_capabilities
[MIGRATION_CAPABILITY_EVENTS
];
1075 int migrate_use_xbzrle(void)
1079 s
= migrate_get_current();
1081 return s
->enabled_capabilities
[MIGRATION_CAPABILITY_XBZRLE
];
1084 int64_t migrate_xbzrle_cache_size(void)
1088 s
= migrate_get_current();
1090 return s
->xbzrle_cache_size
;
1093 /* migration thread support */
1095 * Something bad happened to the RP stream, mark an error
1096 * The caller shall print or trace something to indicate why
1098 static void mark_source_rp_bad(MigrationState
*s
)
1100 s
->rp_state
.error
= true;
1103 static struct rp_cmd_args
{
1104 ssize_t len
; /* -1 = variable */
1107 [MIG_RP_MSG_INVALID
] = { .len
= -1, .name
= "INVALID" },
1108 [MIG_RP_MSG_SHUT
] = { .len
= 4, .name
= "SHUT" },
1109 [MIG_RP_MSG_PONG
] = { .len
= 4, .name
= "PONG" },
1110 [MIG_RP_MSG_MAX
] = { .len
= -1, .name
= "MAX" },
1114 * Handles messages sent on the return path towards the source VM
1117 static void *source_return_path_thread(void *opaque
)
1119 MigrationState
*ms
= opaque
;
1120 QEMUFile
*rp
= ms
->rp_state
.from_dst_file
;
1121 uint16_t header_len
, header_type
;
1122 const int max_len
= 512;
1123 uint8_t buf
[max_len
];
1124 uint32_t tmp32
, sibling_error
;
1127 trace_source_return_path_thread_entry();
1128 while (!ms
->rp_state
.error
&& !qemu_file_get_error(rp
) &&
1129 migration_is_setup_or_active(ms
->state
)) {
1130 trace_source_return_path_thread_loop_top();
1131 header_type
= qemu_get_be16(rp
);
1132 header_len
= qemu_get_be16(rp
);
1134 if (header_type
>= MIG_RP_MSG_MAX
||
1135 header_type
== MIG_RP_MSG_INVALID
) {
1136 error_report("RP: Received invalid message 0x%04x length 0x%04x",
1137 header_type
, header_len
);
1138 mark_source_rp_bad(ms
);
1142 if ((rp_cmd_args
[header_type
].len
!= -1 &&
1143 header_len
!= rp_cmd_args
[header_type
].len
) ||
1144 header_len
> max_len
) {
1145 error_report("RP: Received '%s' message (0x%04x) with"
1146 "incorrect length %d expecting %zu",
1147 rp_cmd_args
[header_type
].name
, header_type
, header_len
,
1148 (size_t)rp_cmd_args
[header_type
].len
);
1149 mark_source_rp_bad(ms
);
1153 /* We know we've got a valid header by this point */
1154 res
= qemu_get_buffer(rp
, buf
, header_len
);
1155 if (res
!= header_len
) {
1156 error_report("RP: Failed reading data for message 0x%04x"
1157 " read %d expected %d",
1158 header_type
, res
, header_len
);
1159 mark_source_rp_bad(ms
);
1163 /* OK, we have the message and the data */
1164 switch (header_type
) {
1165 case MIG_RP_MSG_SHUT
:
1166 sibling_error
= be32_to_cpup((uint32_t *)buf
);
1167 trace_source_return_path_thread_shut(sibling_error
);
1168 if (sibling_error
) {
1169 error_report("RP: Sibling indicated error %d", sibling_error
);
1170 mark_source_rp_bad(ms
);
1173 * We'll let the main thread deal with closing the RP
1174 * we could do a shutdown(2) on it, but we're the only user
1175 * anyway, so there's nothing gained.
1179 case MIG_RP_MSG_PONG
:
1180 tmp32
= be32_to_cpup((uint32_t *)buf
);
1181 trace_source_return_path_thread_pong(tmp32
);
1188 if (rp
&& qemu_file_get_error(rp
)) {
1189 trace_source_return_path_thread_bad_end();
1190 mark_source_rp_bad(ms
);
1193 trace_source_return_path_thread_end();
1195 ms
->rp_state
.from_dst_file
= NULL
;
1200 __attribute__ (( unused
)) /* Until later in patch series */
1201 static int open_return_path_on_source(MigrationState
*ms
)
1204 ms
->rp_state
.from_dst_file
= qemu_file_get_return_path(ms
->file
);
1205 if (!ms
->rp_state
.from_dst_file
) {
1209 trace_open_return_path_on_source();
1210 qemu_thread_create(&ms
->rp_state
.rp_thread
, "return path",
1211 source_return_path_thread
, ms
, QEMU_THREAD_JOINABLE
);
1213 trace_open_return_path_on_source_continue();
1218 __attribute__ (( unused
)) /* Until later in patch series */
1219 /* Returns 0 if the RP was ok, otherwise there was an error on the RP */
1220 static int await_return_path_close_on_source(MigrationState
*ms
)
1223 * If this is a normal exit then the destination will send a SHUT and the
1224 * rp_thread will exit, however if there's an error we need to cause
1227 if (qemu_file_get_error(ms
->file
) && ms
->rp_state
.from_dst_file
) {
1229 * shutdown(2), if we have it, will cause it to unblock if it's stuck
1230 * waiting for the destination.
1232 qemu_file_shutdown(ms
->rp_state
.from_dst_file
);
1233 mark_source_rp_bad(ms
);
1235 trace_await_return_path_close_on_source_joining();
1236 qemu_thread_join(&ms
->rp_state
.rp_thread
);
1237 trace_await_return_path_close_on_source_close();
1238 return ms
->rp_state
.error
;
1242 * migration_completion: Used by migration_thread when there's not much left.
1243 * The caller 'breaks' the loop when this returns.
1245 * @s: Current migration state
1246 * @*old_vm_running: Pointer to old_vm_running flag
1247 * @*start_time: Pointer to time to update
1249 static void migration_completion(MigrationState
*s
, bool *old_vm_running
,
1250 int64_t *start_time
)
1254 qemu_mutex_lock_iothread();
1255 *start_time
= qemu_clock_get_ms(QEMU_CLOCK_REALTIME
);
1256 qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER
);
1257 *old_vm_running
= runstate_is_running();
1259 ret
= global_state_store();
1261 ret
= vm_stop_force_state(RUN_STATE_FINISH_MIGRATE
);
1263 qemu_file_set_rate_limit(s
->file
, INT64_MAX
);
1264 qemu_savevm_state_complete_precopy(s
->file
);
1267 qemu_mutex_unlock_iothread();
1273 if (qemu_file_get_error(s
->file
)) {
1274 trace_migration_completion_file_err();
1278 migrate_set_state(s
, MIGRATION_STATUS_ACTIVE
, MIGRATION_STATUS_COMPLETED
);
1282 migrate_set_state(s
, MIGRATION_STATUS_ACTIVE
, MIGRATION_STATUS_FAILED
);
1286 * Master migration thread on the source VM.
1287 * It drives the migration and pumps the data down the outgoing channel.
1289 static void *migration_thread(void *opaque
)
1291 MigrationState
*s
= opaque
;
1292 int64_t initial_time
= qemu_clock_get_ms(QEMU_CLOCK_REALTIME
);
1293 int64_t setup_start
= qemu_clock_get_ms(QEMU_CLOCK_HOST
);
1294 int64_t initial_bytes
= 0;
1295 int64_t max_size
= 0;
1296 int64_t start_time
= initial_time
;
1298 bool old_vm_running
= false;
1300 rcu_register_thread();
1302 qemu_savevm_state_header(s
->file
);
1303 qemu_savevm_state_begin(s
->file
, &s
->params
);
1305 s
->setup_time
= qemu_clock_get_ms(QEMU_CLOCK_HOST
) - setup_start
;
1306 migrate_set_state(s
, MIGRATION_STATUS_SETUP
, MIGRATION_STATUS_ACTIVE
);
1308 while (s
->state
== MIGRATION_STATUS_ACTIVE
) {
1309 int64_t current_time
;
1310 uint64_t pending_size
;
1312 if (!qemu_file_rate_limit(s
->file
)) {
1313 uint64_t pend_post
, pend_nonpost
;
1315 qemu_savevm_state_pending(s
->file
, max_size
, &pend_nonpost
,
1317 pending_size
= pend_nonpost
+ pend_post
;
1318 trace_migrate_pending(pending_size
, max_size
,
1319 pend_post
, pend_nonpost
);
1320 if (pending_size
&& pending_size
>= max_size
) {
1321 qemu_savevm_state_iterate(s
->file
);
1323 trace_migration_thread_low_pending(pending_size
);
1324 migration_completion(s
, &old_vm_running
, &start_time
);
1329 if (qemu_file_get_error(s
->file
)) {
1330 migrate_set_state(s
, MIGRATION_STATUS_ACTIVE
,
1331 MIGRATION_STATUS_FAILED
);
1334 current_time
= qemu_clock_get_ms(QEMU_CLOCK_REALTIME
);
1335 if (current_time
>= initial_time
+ BUFFER_DELAY
) {
1336 uint64_t transferred_bytes
= qemu_ftell(s
->file
) - initial_bytes
;
1337 uint64_t time_spent
= current_time
- initial_time
;
1338 double bandwidth
= transferred_bytes
/ time_spent
;
1339 max_size
= bandwidth
* migrate_max_downtime() / 1000000;
1341 s
->mbps
= time_spent
? (((double) transferred_bytes
* 8.0) /
1342 ((double) time_spent
/ 1000.0)) / 1000.0 / 1000.0 : -1;
1344 trace_migrate_transferred(transferred_bytes
, time_spent
,
1345 bandwidth
, max_size
);
1346 /* if we haven't sent anything, we don't want to recalculate
1347 10000 is a small enough number for our purposes */
1348 if (s
->dirty_bytes_rate
&& transferred_bytes
> 10000) {
1349 s
->expected_downtime
= s
->dirty_bytes_rate
/ bandwidth
;
1352 qemu_file_reset_rate_limit(s
->file
);
1353 initial_time
= current_time
;
1354 initial_bytes
= qemu_ftell(s
->file
);
1356 if (qemu_file_rate_limit(s
->file
)) {
1357 /* usleep expects microseconds */
1358 g_usleep((initial_time
+ BUFFER_DELAY
- current_time
)*1000);
1362 /* If we enabled cpu throttling for auto-converge, turn it off. */
1363 cpu_throttle_stop();
1364 end_time
= qemu_clock_get_ms(QEMU_CLOCK_REALTIME
);
1366 qemu_mutex_lock_iothread();
1367 qemu_savevm_state_cleanup();
1368 if (s
->state
== MIGRATION_STATUS_COMPLETED
) {
1369 uint64_t transferred_bytes
= qemu_ftell(s
->file
);
1370 s
->total_time
= end_time
- s
->total_time
;
1371 s
->downtime
= end_time
- start_time
;
1372 if (s
->total_time
) {
1373 s
->mbps
= (((double) transferred_bytes
* 8.0) /
1374 ((double) s
->total_time
)) / 1000;
1376 runstate_set(RUN_STATE_POSTMIGRATE
);
1378 if (old_vm_running
) {
1382 qemu_bh_schedule(s
->cleanup_bh
);
1383 qemu_mutex_unlock_iothread();
1385 rcu_unregister_thread();
1389 void migrate_fd_connect(MigrationState
*s
)
1391 /* This is a best 1st approximation. ns to ms */
1392 s
->expected_downtime
= max_downtime
/1000000;
1393 s
->cleanup_bh
= qemu_bh_new(migrate_fd_cleanup
, s
);
1395 qemu_file_set_rate_limit(s
->file
,
1396 s
->bandwidth_limit
/ XFER_LIMIT_RATIO
);
1398 /* Notify before starting migration thread */
1399 notifier_list_notify(&migration_state_notifiers
, s
);
1401 migrate_compress_threads_create();
1402 qemu_thread_create(&s
->thread
, "migration", migration_thread
, s
,
1403 QEMU_THREAD_JOINABLE
);
1406 PostcopyState
postcopy_state_get(void)
1408 return atomic_mb_read(&incoming_postcopy_state
);
1411 /* Set the state and return the old state */
1412 PostcopyState
postcopy_state_set(PostcopyState new_state
)
1414 return atomic_xchg(&incoming_postcopy_state
, new_state
);