[V4,03/11] migration: add runstate function

Commit Message

Steven Sistare Aug. 29, 2023, 6:17 p.m. UTC

Create a subroutine for preserving the runstate after migration,
to be used in a subsequent patch.  No functional change.

Signed-off-by: Steve Sistare <[e-mail]>
Reviewed-by: Fabiano Rosas <[e-mail]>
---
 migration/migration.c | 37 ++++++++++++++++++++++---------------
 migration/migration.h |  1 +
 migration/savevm.c    | 13 +------------
 3 files changed, 24 insertions(+), 27 deletions(-)

Comments

Peter Xu Aug. 30, 2023, 4:11 p.m. UTC | #1

On Tue, Aug 29, 2023 at 11:17:58AM -0700, Steve Sistare wrote:
> Create a subroutine for preserving the runstate after migration,
> to be used in a subsequent patch.  No functional change.

There is actually a functional change when postcopy=on && colo=on, but I
don't think it's a valid use case, so maybe we should fail
migrate_caps_check perhaps when both set?  Not some immediate concern.

> 
> Signed-off-by: Steve Sistare <[e-mail]>
> Reviewed-by: Fabiano Rosas <[e-mail]>

Reviewed-by: Peter Xu <[e-mail]>

Patch

diff --git a/migration/migration.c b/migration/migration.c
index 5bcc761..a9ecb66 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -486,21 +486,8 @@  static void process_incoming_migration_bh(void *opaque)
 
     dirty_bitmap_mig_before_vm_start();
 
-    if (!global_state_received() ||
-        global_state_get_runstate() == RUN_STATE_RUNNING) {
-        if (autostart) {
-            vm_start();
-        } else {
-            runstate_set(RUN_STATE_PAUSED);
-        }
-    } else if (migration_incoming_colo_enabled()) {
-        migration_incoming_disable_colo();
-        vm_start();
-    } else if (global_state_get_runstate() == RUN_STATE_SUSPENDED) {
-        vm_prepare_start(false, global_state_get_runstate());
-    } else {
-        runstate_set(global_state_get_runstate());
-    }
+    migrate_set_runstate();
+
     /*
      * This must happen after any state changes since as soon as an external
      * observer sees this event they might start to prod at the VM assuming
@@ -1143,6 +1130,26 @@  void migrate_set_state(int *state, int old_state, int new_state)
     }
 }
 
+void migrate_set_runstate(void)
+{
+    RunState state = global_state_get_runstate();
+
+    if (!global_state_received() || state == RUN_STATE_RUNNING) {
+        if (autostart) {
+            vm_start();
+        } else {
+            runstate_set(RUN_STATE_PAUSED);
+        }
+    } else if (migration_incoming_colo_enabled()) {
+        migration_incoming_disable_colo();
+        vm_start();
+    } else if (state == RUN_STATE_SUSPENDED) {
+        vm_prepare_start(false, state);
+    } else {
+        runstate_set(state);
+    }
+}
+
 static void migrate_fd_cleanup(MigrationState *s)
 {
     qemu_bh_delete(s->cleanup_bh);
diff --git a/migration/migration.h b/migration/migration.h
index 6eea18d..45e9805 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -456,6 +456,7 @@  struct MigrationState {
 };
 
 void migrate_set_state(int *state, int old_state, int new_state);
+void migrate_set_runstate(void);
 
 void migration_fd_process_incoming(QEMUFile *f, Error **errp);
 void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp);
diff --git a/migration/savevm.c b/migration/savevm.c
index bae0a1a..eba3653 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -2070,18 +2070,7 @@  static void loadvm_postcopy_handle_run_bh(void *opaque)
 
     dirty_bitmap_mig_before_vm_start();
 
-    if (!global_state_received() ||
-        global_state_get_runstate() == RUN_STATE_RUNNING) {
-        if (autostart) {
-            vm_start();
-        } else {
-            runstate_set(RUN_STATE_PAUSED);
-        }
-    } else if (global_state_get_runstate() == RUN_STATE_SUSPENDED) {
-        vm_prepare_start(false, RUN_STATE_SUSPENDED);
-    } else {
-        runstate_set(global_state_get_runstate());
-    }
+    migrate_set_runstate();
 
     qemu_bh_delete(mis->bh);