[Qemu-devel] [PATCH COLO-Frame v13 03/39] COLO: migrate colo related info to secondary node

[zhanghailiang <zhang.zhanghailiang@huawei.com>]

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

We skip this section if colo is not enabled (i.e.
migrate_set_capability colo off), so that, It not break compatibility with migration
however the --enable-colo/disable-colo on the source/destination;

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
v11:
- Add Reviewed-by tag
v10:
- Use VMSTATE_BOOL instead of VMSTATE_UNIT32 for 'colo_requested' (Dave's suggestion).
---
 include/migration/colo.h |  2 ++
 migration/Makefile.objs  |  1 +
 migration/colo-comm.c    | 50 ++++++++++++++++++++++++++++++++++++++++++++++++
 vl.c                     |  3 ++-
 4 files changed, 55 insertions(+), 1 deletion(-)
 create mode 100644 migration/colo-comm.c

diff --git a/include/migration/colo.h b/include/migration/colo.h
index c60a590..9b6662d 100644
--- a/include/migration/colo.h
+++ b/include/migration/colo.h
@@ -14,7 +14,9 @@
 #define QEMU_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 65ecc35..81b5713 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 postcopy-ram.o
diff --git a/migration/colo-comm.c b/migration/colo-comm.c
new file mode 100644
index 0000000..fb407e0
--- /dev/null
+++ b/migration/colo-comm.c
@@ -0,0 +1,50 @@
+/*
+ * 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/colo.h>
+#include "trace.h"
+
+typedef struct {
+     bool colo_requested;
+} COLOInfo;
+
+static COLOInfo colo_info;
+
+static void colo_info_pre_save(void *opaque)
+{
+    COLOInfo *s = opaque;
+
+    s->colo_requested = migrate_colo_enabled();
+}
+
+static bool colo_info_need(void *opaque)
+{
+   return migrate_colo_enabled();
+}
+
+static const VMStateDescription colo_state = {
+     .name = "COLOState",
+     .version_id = 1,
+     .minimum_version_id = 1,
+     .pre_save = colo_info_pre_save,
+     .needed = colo_info_need,
+     .fields = (VMStateField[]) {
+         VMSTATE_BOOL(colo_requested, COLOInfo),
+         VMSTATE_END_OF_LIST()
+        },
+};
+
+void colo_info_mig_init(void)
+{
+    vmstate_register(NULL, 0, &colo_state, &colo_info);
+}
diff --git a/vl.c b/vl.c
index 5aaea77..5ac49ce 100644
--- a/vl.c
+++ b/vl.c
@@ -91,6 +91,7 @@ int main(int argc, char **argv)
 #include "sysemu/dma.h"
 #include "audio/audio.h"
 #include "migration/migration.h"
+#include "migration/colo.h"
 #include "sysemu/kvm.h"
 #include "qapi/qmp/qjson.h"
 #include "qemu/option.h"
@@ -4450,7 +4451,7 @@ int main(int argc, char **argv, char **envp)
 
     blk_mig_init();
     ram_mig_init();
-
+    colo_info_mig_init();
     /* 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) {
-- 
1.8.3.1