Creating new message to reply for MIG_CMD_POSTCOPY_RESUME. One uint32_t
is used as payload to let the source know whether destination is ready
to continue the migration.
Signed-off-by: Peter Xu <pet...@redhat.com>
---
migration/migration.c | 37 +++++++++++++++++++++++++++++++++++++
migration/migration.h | 1 +
migration/savevm.c | 3 ++-
migration/trace-events | 1 +
4 files changed, 41 insertions(+), 1 deletion(-)
diff --git a/migration/migration.c b/migration/migration.c
index c2b85ac..62f91ce 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -93,6 +93,7 @@ enum mig_rp_message_type {
MIG_RP_MSG_REQ_PAGES_ID, /* data (start: be64, len: be32, id: string) */
MIG_RP_MSG_REQ_PAGES, /* data (start: be64, len: be32) */
MIG_RP_MSG_RECV_BITMAP, /* send recved_bitmap back to source */
+ MIG_RP_MSG_RESUME_ACK, /* tell source that we are ready to resume */
MIG_RP_MSG_MAX
};
@@ -484,6 +485,14 @@ void migrate_send_rp_recv_bitmap(MigrationIncomingState
*mis,
trace_migrate_send_rp_recv_bitmap(block_name, res);
}
+void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value)
+{
+ uint32_t buf;
+
+ buf = cpu_to_be32(value);
+ migrate_send_rp_message(mis, MIG_RP_MSG_RESUME_ACK, sizeof(buf), &buf);
+}
+
MigrationCapabilityStatusList *qmp_query_migrate_capabilities(Error **errp)
{
MigrationCapabilityStatusList *head = NULL;
@@ -1595,6 +1604,7 @@ static struct rp_cmd_args {
[MIG_RP_MSG_REQ_PAGES] = { .len = 12, .name = "REQ_PAGES" },
[MIG_RP_MSG_REQ_PAGES_ID] = { .len = -1, .name = "REQ_PAGES_ID" },
[MIG_RP_MSG_RECV_BITMAP] = { .len = -1, .name = "RECV_BITMAP" },
+ [MIG_RP_MSG_RESUME_ACK] = { .len = 4, .name = "RESUME_ACK" },
[MIG_RP_MSG_MAX] = { .len = -1, .name = "MAX" },
};
@@ -1652,6 +1662,25 @@ static int migrate_handle_rp_recv_bitmap(MigrationState
*s, char *block_name)
return ram_dirty_bitmap_reload(s, block);
}
+static int migrate_handle_rp_resume_ack(MigrationState *s, uint32_t value)
+{
+ trace_source_return_path_thread_resume_ack(value);
+
+ /*
+ * Currently value will always be one. It can be used in the
+ * future to notify source that destination cannot continue.
+ */
+ assert(value == 1);
+
+ /* Now both sides are active. */
+ migrate_set_state(&s->state, MIGRATION_STATUS_POSTCOPY_RECOVER,
+ MIGRATION_STATUS_POSTCOPY_ACTIVE);
+
+ /* TODO: notify send thread that time to continue send pages */
+
+ return 0;
+}
+
/*
* Handles messages sent on the return path towards the source VM
*
@@ -1771,6 +1800,14 @@ retry:
}
break;
+ case MIG_RP_MSG_RESUME_ACK:
+ tmp32 = ldl_be_p(buf);
+ if (migrate_handle_rp_resume_ack(ms, tmp32)) {
+ mark_source_rp_bad(ms);
+ goto out;
+ }
+ break;
+
default:
break;
}
diff --git a/migration/migration.h b/migration/migration.h
index 4d38308..2a3f905 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -206,5 +206,6 @@ int migrate_send_rp_req_pages(MigrationIncomingState *mis,
const char* rbname,
ram_addr_t start, size_t len);
void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis,
char *block_name);
+void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value);
#endif
diff --git a/migration/savevm.c b/migration/savevm.c
index 2e330bc..02a67ac 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -1690,7 +1690,8 @@ static int
loadvm_postcopy_handle_resume(MigrationIncomingState *mis)
MIGRATION_STATUS_POSTCOPY_ACTIVE);
qemu_sem_post(&mis->postcopy_pause_sem_fault);
- /* TODO: Tell source that "we are ready" */
+ /* Tell source that "we are ready" */
+ migrate_send_rp_resume_ack(mis, 1);
return 0;
}
diff --git a/migration/trace-events b/migration/trace-events
index 04dd9d8..0b43fec 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -116,6 +116,7 @@ source_return_path_thread_entry(void) ""
source_return_path_thread_loop_top(void) ""
source_return_path_thread_pong(uint32_t val) "%x"
source_return_path_thread_shut(uint32_t val) "%x"
+source_return_path_thread_resume_ack(uint32_t v) "%"PRIu32
migrate_global_state_post_load(const char *state) "loaded state: %s"
migrate_global_state_pre_save(const char *state) "saved state: %s"
migration_thread_low_pending(uint64_t pending) "%" PRIu64
--
2.7.4
