[Qemu-devel] [RFC PATCH v4 03/28] COLO: migrate colo related info to slave

[zhanghailiang]

We can know if VM in destination should go into COLO mode by refer to
the info that has been migrated from PVM.

Signed-off-by: zhanghailiang <address@hidden>
Signed-off-by: Yang Hongyang <address@hidden>
Signed-off-by: Lai Jiangshan <address@hidden>
Signed-off-by: Gonglei <address@hidden>
---
 include/migration/migration-colo.h |  2 ++
 migration/Makefile.objs            |  1 +
 migration/colo-comm.c              | 55 ++++++++++++++++++++++++++++++++++++++
 vl.c                               |  5 +++-
 4 files changed, 62 insertions(+), 1 deletion(-)
 create mode 100644 migration/colo-comm.c

diff --git a/include/migration/migration-colo.h 
b/include/migration/migration-colo.h
index 6fdbb94..de68c72 100644
--- a/include/migration/migration-colo.h
+++ b/include/migration/migration-colo.h
@@ -14,7 +14,9 @@
 #define QEMU_MIGRATION_COLO_H
 
 #include "qemu-common.h"
+#include "migration/migration.h"
 
 bool colo_supported(void);
+void colo_info_mig_init(void);
 
 #endif
diff --git a/migration/Makefile.objs b/migration/Makefile.objs
index 5a25d39..cb7bd30 100644
--- a/migration/Makefile.objs
+++ b/migration/Makefile.objs
@@ -1,5 +1,6 @@
 common-obj-y += migration.o tcp.o
 common-obj-$(CONFIG_COLO) += colo.o
+common-obj-y += colo-comm.o
 common-obj-y += vmstate.o
 common-obj-y += qemu-file.o qemu-file-buf.o qemu-file-unix.o qemu-file-stdio.o
 common-obj-y += xbzrle.o
diff --git a/migration/colo-comm.c b/migration/colo-comm.c
new file mode 100644
index 0000000..cab97e9
--- /dev/null
+++ b/migration/colo-comm.c
@@ -0,0 +1,55 @@
+/*
+ * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO)
+ * (a.k.a. Fault Tolerance or Continuous Replication)
+ *
+ * Copyright (c) 2015 HUAWEI TECHNOLOGIES CO.,LTD.
+ * Copyright (c) 2015 FUJITSU LIMITED
+ * Copyright (c) 2015 Intel Corporation
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later. See the COPYING file in the top-level directory.
+ *
+ */
+
+#include <migration/migration-colo.h>
+
+#define DEBUG_COLO_COMMON 0
+
+#define DPRINTF(fmt, ...)                                  \
+    do {                                                   \
+        if (DEBUG_COLO_COMMON) {                           \
+            fprintf(stderr, "COLO: " fmt, ## __VA_ARGS__); \
+        }                                                  \
+    } while (0)
+
+static bool colo_requested;
+
+/* save */
+static void colo_info_save(QEMUFile *f, void *opaque)
+{
+    qemu_put_byte(f, migrate_enable_colo());
+}
+
+/* restore */
+static int colo_info_load(QEMUFile *f, void *opaque, int version_id)
+{
+    int value = qemu_get_byte(f);
+
+    if (value && !colo_requested) {
+        DPRINTF("COLO requested!\n");
+    }
+    colo_requested = value;
+
+    return 0;
+}
+
+static SaveVMHandlers savevm_colo_info_handlers = {
+    .save_state = colo_info_save,
+    .load_state = colo_info_load,
+};
+
+void colo_info_mig_init(void)
+{
+    register_savevm_live(NULL, "colo", -1, 1,
+                         &savevm_colo_info_handlers, NULL);
+}
diff --git a/vl.c b/vl.c
index 75ec292..9724992 100644
--- a/vl.c
+++ b/vl.c
@@ -90,6 +90,7 @@ int main(int argc, char **argv)
 #include "sysemu/dma.h"
 #include "audio/audio.h"
 #include "migration/migration.h"
+#include "migration/migration-colo.h"
 #include "sysemu/kvm.h"
 #include "qapi/qmp/qjson.h"
 #include "qemu/option.h"
@@ -4149,7 +4150,9 @@ int main(int argc, char **argv, char **envp)
 
     blk_mig_init();
     ram_mig_init();
-
+#ifdef CONFIG_COLO
+    colo_info_mig_init();
+#endif
     /* If the currently selected machine wishes to override the units-per-bus
      * property of its default HBA interface type, do so now. */
     if (machine_class->units_per_default_bus) {
-- 
1.7.12.4