The first allow-oob=true command. It's used on destination side when
the postcopy migration is paused and ready for a recovery. After
execution, a new migration channel will be established for postcopy to
continue.
Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
Signed-off-by: Peter Xu <pet...@redhat.com>
---
qapi/migration.json | 20 ++++++++++++++++++++
migration/migration.h | 1 +
migration/migration.c | 24 ++++++++++++++++++++++++
migration/savevm.c | 3 +++
4 files changed, 48 insertions(+)
diff --git a/qapi/migration.json b/qapi/migration.json
index 25a6776af6..a1c2c238ab 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -1191,3 +1191,23 @@
# Since: 2.9
##
{ 'command': 'xen-colo-do-checkpoint' }
+
+##
+# @migrate-recover:
+#
+# Provide a recovery migration stream URI.
+#
+# @uri: the URI to be used for the recovery of migration stream.
+#
+# Returns: nothing.
+#
+# Example:
+#
+# -> { "execute": "migrate-recover",
+# "arguments": { "uri": "tcp:192.168.1.200:12345" } }
+# <- { "return": {} }
+#
+# Since: 2.12
+##
+{ 'command': 'migrate-recover', 'data': { 'uri': 'str' },
+ 'allow-oob': true }
diff --git a/migration/migration.h b/migration/migration.h
index 2f0dc34ae9..012bcd352b 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -77,6 +77,7 @@ struct MigrationIncomingState {
struct PostcopyBlocktimeContext *blocktime_ctx;
/* notify PAUSED postcopy incoming migrations to try to continue */
+ bool postcopy_recover_triggered;
QemuSemaphore postcopy_pause_sem_dst;
QemuSemaphore postcopy_pause_sem_fault;
};
diff --git a/migration/migration.c b/migration/migration.c
index c059579fee..03d1fc7bc3 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1470,6 +1470,30 @@ void qmp_migrate_incoming(const char *uri, Error **errp)
once = false;
}
+void qmp_migrate_recover(const char *uri, Error **errp)
+{
+ MigrationIncomingState *mis = migration_incoming_get_current();
+
+ if (mis->state != MIGRATION_STATUS_POSTCOPY_PAUSED) {
+ error_setg(errp, "Migrate recover can only be run "
+ "when postcopy is paused.");
+ return;
+ }
+
+ if (atomic_cmpxchg(&mis->postcopy_recover_triggered,
+ false, true) == true) {
+ error_setg(errp, "Migrate recovery is triggered already");
+ return;
+ }
+
+ /*
+ * Note that this call will never start a real migration; it will
+ * only re-setup the migration stream and poke existing migration
+ * to continue using that newly established channel.
+ */
+ qemu_start_incoming_migration(uri, errp);
+}
+
bool migration_is_blocked(Error **errp)
{
if (qemu_savevm_state_blocked(errp)) {
diff --git a/migration/savevm.c b/migration/savevm.c
index 8e7653badc..4251125831 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -2190,6 +2190,9 @@ static bool
postcopy_pause_incoming(MigrationIncomingState *mis)
{
trace_postcopy_pause_incoming();
+ /* Clear the triggered bit to allow one recovery */
+ mis->postcopy_recover_triggered = false;
+
migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE,
MIGRATION_STATUS_POSTCOPY_PAUSED);
--
2.14.3
