@@ -95,6 +95,9 @@ enum mig_rp_message_type {
MIG_RP_MSG_MAX
};
+/* Migration channel types */
+enum { CH_MAIN, CH_MULTIFD, CH_POSTCOPY };
+
/* When we add fault tolerance, we could have several
migrations at once. For now we don't need to add
dynamic creation of migration */
@@ -947,28 +950,19 @@ void migration_fd_process_incoming(QEMUFile *f)
migration_incoming_process();
}
-/*
- * Returns true when we want to start a new incoming migration process,
- * false otherwise.
- */
-static bool migration_should_start_incoming(bool main_channel)
+static bool migration_has_main_and_multifd_channels(void)
{
- /* Multifd doesn't start unless all channels are established */
- if (migrate_multifd()) {
- return migration_has_all_channels();
+ MigrationIncomingState *mis = migration_incoming_get_current();
+ if (!mis->from_src_file) {
+ /* main channel not established */
+ return false;
}
- /* Preempt channel only starts when the main channel is created */
- if (migrate_postcopy_preempt()) {
- return main_channel;
+ if (migrate_multifd() && !multifd_recv_all_channels_created()) {
+ return false;
}
- /*
- * For all the rest types of migration, we should only reach here when
- * it's the main channel that's being created, and we should always
- * proceed with this channel.
- */
- assert(main_channel);
+ /* main channel and all multifd channels are established */
return true;
}
@@ -977,59 +971,84 @@ void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp)
MigrationIncomingState *mis = migration_incoming_get_current();
Error *local_err = NULL;
QEMUFile *f;
- bool default_channel = true;
+ uint8_t channel;
uint32_t channel_magic = 0;
int ret = 0;
- if (migrate_multifd() && !migrate_mapped_ram() &&
- !migrate_postcopy_ram() &&
- qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_READ_MSG_PEEK)) {
- /*
- * With multiple channels, it is possible that we receive channels
- * out of order on destination side, causing incorrect mapping of
- * source channels on destination side. Check channel MAGIC to
- * decide type of channel. Please note this is best effort, postcopy
- * preempt channel does not send any magic number so avoid it for
- * postcopy live migration. Also tls live migration already does
- * tls handshake while initializing main channel so with tls this
- * issue is not possible.
- */
- ret = migration_channel_read_peek(ioc, (void *)&channel_magic,
- sizeof(channel_magic), errp);
+ if (!migration_has_main_and_multifd_channels()) {
+ if (qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_READ_MSG_PEEK)) {
+ /*
+ * With multiple channels, it is possible that we receive channels
+ * out of order on destination side, causing incorrect mapping of
+ * source channels on destination side. Check channel MAGIC to
+ * decide type of channel. Please note this is best effort,
+ * postcopy preempt channel does not send any magic number so
+ * avoid it for postcopy live migration. Also tls live migration
+ * already does tls handshake while initializing main channel so
+ * with tls this issue is not possible.
+ */
+ ret = migration_channel_read_peek(ioc, (void *)&channel_magic,
+ sizeof(channel_magic), errp);
+ if (ret != 0) {
+ return;
+ }
- if (ret != 0) {
+ channel_magic = be32_to_cpu(channel_magic);
+ if (channel_magic == QEMU_VM_FILE_MAGIC) {
+ channel = CH_MAIN;
+ } else if (channel_magic == MULTIFD_MAGIC) {
+ channel = CH_MULTIFD;
+ } else if (!mis->from_src_file &&
+ mis->state == MIGRATION_STATUS_POSTCOPY_PAUSED) {
+ /* reconnect main channel for postcopy recovery */
+ channel = CH_MAIN;
+ } else {
+ error_setg(errp, "unknown channel magic: %u", channel_magic);
+ return;
+ }
+ } else if (mis->from_src_file && migrate_multifd()) {
+ /*
+ * Non-peekable channels like tls/file are processed as
+ * multifd channels when multifd is enabled.
+ */
+ channel = CH_MULTIFD;
+ } else if (!mis->from_src_file) {
+ channel = CH_MAIN;
+ } else {
+ error_setg(errp, "non-peekable channel used without multifd");
return;
}
-
- default_channel = (channel_magic == cpu_to_be32(QEMU_VM_FILE_MAGIC));
+ } else if (mis->from_src_file) {
+ channel = CH_POSTCOPY;
} else {
- default_channel = !mis->from_src_file;
+ channel = CH_MAIN;
}
if (multifd_recv_setup(errp) != 0) {
return;
}
- if (default_channel) {
+ if (channel == CH_MAIN) {
f = qemu_file_new_input(ioc);
migration_incoming_setup(f);
- } else {
+ } else if (channel == CH_MULTIFD) {
/* Multiple connections */
- assert(migration_needs_multiple_sockets());
if (migrate_multifd()) {
multifd_recv_new_channel(ioc, &local_err);
- } else {
- assert(migrate_postcopy_preempt());
- f = qemu_file_new_input(ioc);
- postcopy_preempt_new_channel(mis, f);
}
if (local_err) {
error_propagate(errp, local_err);
return;
}
+ } else if (channel == CH_POSTCOPY) {
+ assert(migrate_postcopy_preempt());
+ assert(!mis->postcopy_qemufile_dst);
+ f = qemu_file_new_input(ioc);
+ postcopy_preempt_new_channel(mis, f);
+ return;
}
- if (migration_should_start_incoming(default_channel)) {
+ if (migration_has_main_and_multifd_channels()) {
/* If it's a recovery, we're done */
if (postcopy_try_recover()) {
return;
@@ -1046,20 +1065,15 @@ void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp)
*/
bool migration_has_all_channels(void)
{
+ if (!migration_has_main_and_multifd_channels()) {
+ return false;
+ }
+
MigrationIncomingState *mis = migration_incoming_get_current();
-
- if (!mis->from_src_file) {
+ if (migrate_postcopy_preempt() && !mis->postcopy_qemufile_dst) {
return false;
}
- if (migrate_multifd()) {
- return multifd_recv_all_channels_created();
- }
-
- if (migrate_postcopy_preempt()) {
- return mis->postcopy_qemufile_dst != NULL;
- }
-
return true;
}
@@ -1470,6 +1484,8 @@ static void migration_cleanup(MigrationState *s)
assert(!migration_is_active());
+ file_cleanup_outgoing_migration();
+ socket_cleanup_outgoing_migration();
if (s->state == MIGRATION_STATUS_CANCELLING) {
migrate_set_state(&s->state, MIGRATION_STATUS_CANCELLING,
MIGRATION_STATUS_CANCELLED);
@@ -3382,8 +3398,11 @@ static MigIterateState migration_iteration_run(MigrationState *s)
}
/* Still a significant amount to transfer */
- if (!in_postcopy && must_precopy <= s->threshold_size && can_switchover &&
- qatomic_read(&s->start_postcopy)) {
+ if (!in_postcopy && must_precopy <= s->threshold_size
+ && can_switchover && qatomic_read(&s->start_postcopy)) {
+ if (migrate_multifd()) {
+ multifd_send_shutdown();
+ }
if (postcopy_start(s, &local_err)) {
migrate_set_error(s, local_err);
error_report_err(local_err);
@@ -16,6 +16,7 @@
#include "file.h"
#include "multifd.h"
#include "options.h"
+#include "migration.h"
#include "qapi/error.h"
#include "qemu/cutils.h"
#include "qemu/error-report.h"
@@ -391,7 +392,7 @@ int multifd_ram_flush_and_sync(QEMUFile *f)
MultiFDSyncReq req;
int ret;
- if (!migrate_multifd()) {
+ if (!migrate_multifd() || migration_in_postcopy()) {
return 0;
}
@@ -467,8 +467,6 @@ static bool multifd_send_cleanup_channel(MultiFDSendParams *p, Error **errp)
static void multifd_send_cleanup_state(void)
{
- file_cleanup_outgoing_migration();
- socket_cleanup_outgoing_migration();
qemu_sem_destroy(&multifd_send_state->channels_created);
qemu_sem_destroy(&multifd_send_state->channels_ready);
g_free(multifd_send_state->params);
@@ -481,7 +479,7 @@ void multifd_send_shutdown(void)
{
int i;
- if (!migrate_multifd()) {
+ if (!migrate_multifd() || !multifd_send_state) {
return;
}
@@ -1231,6 +1229,13 @@ static void *multifd_recv_thread(void *opaque)
}
if (has_data) {
+ /*
+ * multifd thread should not be active and receive data
+ * when migration is in the Postcopy phase. Two threads
+ * writing the same memory area could easily corrupt
+ * the guest state.
+ */
+ assert(!migration_in_postcopy());
ret = multifd_recv_state->ops->recv(p, &local_err);
if (ret != 0) {
break;
@@ -482,11 +482,6 @@ bool migrate_caps_check(bool *old_caps, bool *new_caps, Error **errp)
error_setg(errp, "Postcopy is not compatible with ignore-shared");
return false;
}
-
- if (new_caps[MIGRATION_CAPABILITY_MULTIFD]) {
- error_setg(errp, "Postcopy is not yet compatible with multifd");
- return false;
- }
}
if (new_caps[MIGRATION_CAPABILITY_BACKGROUND_SNAPSHOT]) {
@@ -1297,7 +1297,7 @@ static int find_dirty_block(RAMState *rs, PageSearchStatus *pss)
pss->page = 0;
pss->block = QLIST_NEXT_RCU(pss->block, next);
if (!pss->block) {
- if (multifd_ram_sync_per_round()) {
+ if (multifd_ram_sync_per_round() && !migration_in_postcopy()) {
QEMUFile *f = rs->pss[RAM_CHANNEL_PRECOPY].pss_channel;
int ret = multifd_ram_flush_and_sync(f);
if (ret < 0) {
@@ -1971,9 +1971,8 @@ static int ram_save_target_page(RAMState *rs, PageSearchStatus *pss)
}
}
- if (migrate_multifd()) {
- RAMBlock *block = pss->block;
- return ram_save_multifd_page(block, offset);
+ if (migrate_multifd() && !migration_in_postcopy()) {
+ return ram_save_multifd_page(pss->block, offset);
}
if (control_save_page(pss, offset, &res)) {