migration: unfold rest of migrate_fd_put_ready() into thread

This will allow us finer control in next patches.
Signed-off-by: NJuan Quintela <quintela@redhat.com>
Reviewed-by: NReviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>

migration.c

@@ -662,20 +662,47 @@ static int64_t buffered_get_rate_limit(void *opaque)
     return s->xfer_limit;
 }
 
-static bool migrate_fd_put_ready(MigrationState *s, uint64_t max_size)
+static void *buffered_file_thread(void *opaque)
 {
+    MigrationState *s = opaque;
+    int64_t initial_time = qemu_get_clock_ms(rt_clock);
+    int64_t max_size = 0;
+    bool last_round = false;
     int ret;
+
+    qemu_mutex_lock_iothread();
+    DPRINTF("beginning savevm\n");
+    ret = qemu_savevm_state_begin(s->file, &s->params);
+    if (ret < 0) {
+        DPRINTF("failed, %d\n", ret);
+        qemu_mutex_unlock_iothread();
+        goto out;
+    }
+    qemu_mutex_unlock_iothread();
+
+    while (true) {
+        int64_t current_time = qemu_get_clock_ms(rt_clock);
         uint64_t pending_size;
-    bool last_round = false;
 
         qemu_mutex_lock_iothread();
+        if (s->state != MIG_STATE_ACTIVE) {
+            DPRINTF("put_ready returning because of non-active state\n");
+            qemu_mutex_unlock_iothread();
+            break;
+        }
+        if (s->complete) {
+            qemu_mutex_unlock_iothread();
+            break;
+        }
+        if (s->bytes_xfer < s->xfer_limit) {
             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 >= max_size) {
                 ret = qemu_savevm_state_iterate(s->file);
                 if (ret < 0) {
-            migrate_fd_error(s);
+                    qemu_mutex_unlock_iothread();
+                    break;
                 }
             } else {
                 int old_vm_running = runstate_is_running();
@@ -689,9 +716,10 @@ static bool migrate_fd_put_ready(MigrationState *s, uint64_t max_size)
                 } else {
                     vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
                 }
-
-        if (qemu_savevm_state_complete(s->file) < 0) {
-            migrate_fd_error(s);
+                ret = qemu_savevm_state_complete(s->file);
+                if (ret < 0) {
+                    qemu_mutex_unlock_iothread();
+                    break;
                 } else {
                     migrate_fd_completed(s);
                 }
@@ -705,41 +733,6 @@ static bool migrate_fd_put_ready(MigrationState *s, uint64_t max_size)
                 }
                 last_round = true;
             }
-    qemu_mutex_unlock_iothread();
-
-    return last_round;
-}
-
-static void *buffered_file_thread(void *opaque)
-{
-    MigrationState *s = opaque;
-    int64_t initial_time = qemu_get_clock_ms(rt_clock);
-    int64_t max_size = 0;
-    bool last_round = false;
-    int ret;
-
-    qemu_mutex_lock_iothread();
-    DPRINTF("beginning savevm\n");
-    ret = qemu_savevm_state_begin(s->file, &s->params);
-    if (ret < 0) {
-        DPRINTF("failed, %d\n", ret);
-        qemu_mutex_unlock_iothread();
-        goto out;
-    }
-    qemu_mutex_unlock_iothread();
-
-    while (true) {
-        int64_t current_time = qemu_get_clock_ms(rt_clock);
-
-        qemu_mutex_lock_iothread();
-        if (s->state != MIG_STATE_ACTIVE) {
-            DPRINTF("put_ready returning because of non-active state\n");
-            qemu_mutex_unlock_iothread();
-            break;
-        }
-        if (s->complete) {
-            qemu_mutex_unlock_iothread();
-            break;
         }
         qemu_mutex_unlock_iothread();
         if (current_time >= initial_time + BUFFER_DELAY) {
@@ -763,12 +756,6 @@ static void *buffered_file_thread(void *opaque)
         if (ret < 0) {
             break;
         }
-
-        DPRINTF("file is ready\n");
-        if (s->bytes_xfer < s->xfer_limit) {
-            DPRINTF("notifying client\n");
-            last_round = migrate_fd_put_ready(s, max_size);
-        }
     }
 
 out: