migration: Split save_live_pending() into state_pending_*

We split the function into to:

- state_pending_estimate: We estimate the remaining state size without
  stopping the machine.

- state pending_exact: We calculate the exact amount of remaining
  state.

The only "device" that implements different functions for _estimate()
and _exact() is ram.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

1 files changed, 34 insertions, 8 deletions

diff --git a/migration/savevm.c b/migration/savevm.c
index 5e4bccb966..7f9f770c1e 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -1472,10 +1472,10 @@ flush:
  * the result is split into the amount for units that can and
  * for units that can't do postcopy.
  */
-void qemu_savevm_state_pending(uint64_t threshold_size,
-                               uint64_t *res_precopy_only,
-                               uint64_t *res_compatible,
-                               uint64_t *res_postcopy_only)
+void qemu_savevm_state_pending_estimate(uint64_t threshold_size,
+                                        uint64_t *res_precopy_only,
+                                        uint64_t *res_compatible,
+                                        uint64_t *res_postcopy_only)
 {
     SaveStateEntry *se;
 
@@ -1485,7 +1485,7 @@ void qemu_savevm_state_pending(uint64_t threshold_size,
 
 
     QTAILQ_FOREACH(se, &savevm_state.handlers, entry) {
-        if (!se->ops || !se->ops->save_live_pending) {
+        if (!se->ops || !se->ops->state_pending_exact) {
             continue;
         }
         if (se->ops->is_active) {
@@ -1493,9 +1493,35 @@ void qemu_savevm_state_pending(uint64_t threshold_size,
                 continue;
             }
         }
-        se->ops->save_live_pending(se->opaque, threshold_size,
-                                   res_precopy_only, res_compatible,
-                                   res_postcopy_only);
+        se->ops->state_pending_exact(se->opaque, threshold_size,
+                                     res_precopy_only, res_compatible,
+                                     res_postcopy_only);
+    }
+}
+
+void qemu_savevm_state_pending_exact(uint64_t threshold_size,
+                                     uint64_t *res_precopy_only,
+                                     uint64_t *res_compatible,
+                                     uint64_t *res_postcopy_only)
+{
+    SaveStateEntry *se;
+
+    *res_precopy_only = 0;
+    *res_compatible = 0;
+    *res_postcopy_only = 0;
+
+    QTAILQ_FOREACH(se, &savevm_state.handlers, entry) {
+        if (!se->ops || !se->ops->state_pending_estimate) {
+            continue;
+        }
+        if (se->ops->is_active) {
+            if (!se->ops->is_active(se->opaque)) {
+                continue;
+            }
+        }
+        se->ops->state_pending_estimate(se->opaque, threshold_size,
+                                        res_precopy_only, res_compatible,
+                                        res_postcopy_only);
     }
 }