[Qemu-devel] [PATCH 15/18] migration: adjust migration_thread for local migration

[Lei Li <lilei@linux.vnet.ibm.com>]

Integrate localhost migration thread to migration_thread. As the mechanism
of local migration is different than the current migration, and it does
not need to do iterate.

So the whole thread can split into two stages, it will send all the ram
pages in qemu_savevm_state_begin stage, and send the device states in
qemu_save_device_state stage.

Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
---
 migration.c |   73 ++++++++++++++++++++++++++++++++++++----------------------
 1 files changed, 45 insertions(+), 28 deletions(-)

diff --git a/migration.c b/migration.c
index 2f85358..2471664 100644
--- a/migration.c
+++ b/migration.c
@@ -565,37 +565,54 @@ static void *migration_thread(void *opaque)
     while (s->state == MIG_STATE_ACTIVE) {
         int64_t current_time;
         uint64_t pending_size;
+        int ret;
 
-        if (!qemu_file_rate_limit(s->file)) {
-            DPRINTF("iterate\n");
-            pending_size = qemu_savevm_state_pending(s->file, max_size);
-            DPRINTF("pending size %lu max %lu\n", pending_size, max_size);
-            if (pending_size && pending_size >= max_size) {
-                qemu_savevm_state_iterate(s->file);
-            } else {
-                int ret;
-
-                DPRINTF("done iterating\n");
-                qemu_mutex_lock_iothread();
-                start_time = qemu_get_clock_ms(rt_clock);
-                qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
-                old_vm_running = runstate_is_running();
-
-                ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
-                if (ret >= 0) {
-                    qemu_file_set_rate_limit(s->file, INT_MAX);
-                    qemu_savevm_state_complete(s->file);
-                }
-                qemu_mutex_unlock_iothread();
+        if (s->enabled_capabilities[MIGRATION_CAPABILITY_LOCALHOST]) {
+            DPRINTF("local migration start\n");
 
-                if (ret < 0) {
-                    migrate_set_state(s, MIG_STATE_ACTIVE, MIG_STATE_ERROR);
-                    break;
-                }
+            ret = qemu_save_device_state(s->file);
+            if (ret < 0) {
+                migrate_set_state(s, MIG_STATE_ACTIVE, MIG_STATE_ERROR);
+                break;
+            }
 
-                if (!qemu_file_get_error(s->file)) {
-                    migrate_set_state(s, MIG_STATE_ACTIVE, MIG_STATE_COMPLETED);
-                    break;
+            if (!qemu_file_get_error(s->file)) {
+                DPRINTF("local migration completed\n");
+                migrate_set_state(s, MIG_STATE_ACTIVE, MIG_STATE_COMPLETED);
+                break;
+            }
+        } else {
+            if (!qemu_file_rate_limit(s->file)) {
+                DPRINTF("iterate\n");
+                pending_size = qemu_savevm_state_pending(s->file, max_size);
+                DPRINTF("pending size %lu max %lu\n", pending_size, max_size);
+                if (pending_size && pending_size >= max_size) {
+                    qemu_savevm_state_iterate(s->file);
+                } else {
+                    int ret;
+
+                    DPRINTF("done iterating\n");
+                    qemu_mutex_lock_iothread();
+                    start_time = qemu_get_clock_ms(rt_clock);
+                    qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
+                    old_vm_running = runstate_is_running();
+
+                    ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
+                    if (ret >= 0) {
+                        qemu_file_set_rate_limit(s->file, INT_MAX);
+                        qemu_savevm_state_complete(s->file);
+                    }
+                    qemu_mutex_unlock_iothread();
+
+                    if (ret < 0) {
+                        migrate_set_state(s, MIG_STATE_ACTIVE, MIG_STATE_ERROR);
+                        break;
+                    }
+
+                    if (!qemu_file_get_error(s->file)) {
+                        migrate_set_state(s, MIG_STATE_ACTIVE, MIG_STATE_COMPLETED);
+                        break;
+                    }
                 }
             }
         }
-- 
1.7.7.6