[Qemu-devel] [PATCH COLO-Frame v10 17/38] COLO: synchronize PVM's state to SVM periodically

[zhanghailiang]

Do checkpoint periodically, the default interval is 200ms.

Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com>
Signed-off-by: Li Zhijian <lizhij...@cn.fujitsu.com>
---
 migration/colo.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/migration/colo.c b/migration/colo.c
index 0efab21..a6791f4 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -11,12 +11,19 @@
  */
 
 #include <unistd.h>
+#include "qemu/timer.h"
 #include "sysemu/sysemu.h"
 #include "migration/colo.h"
 #include "trace.h"
 #include "qemu/error-report.h"
 #include "qemu/sockets.h"
 
+/*
+ * checkpoint interval: unit ms
+ * Note: Please change this default value to 10000 when we support hybrid mode.
+ */
+#define CHECKPOINT_MAX_PEROID 200
+
 /* colo buffer */
 #define COLO_BUFFER_BASE_SIZE (4 * 1024 * 1024)
 
@@ -183,6 +190,7 @@ out:
 static void colo_process_checkpoint(MigrationState *s)
 {
     QEMUSizedBuffer *buffer = NULL;
+    int64_t current_time, checkpoint_time = qemu_clock_get_ms(QEMU_CLOCK_HOST);
     int fd, ret = 0;
 
     /* Dup the fd of to_dst_file */
@@ -220,11 +228,17 @@ static void colo_process_checkpoint(MigrationState *s)
     trace_colo_vm_state_change("stop", "run");
 
     while (s->state == MIGRATION_STATUS_COLO) {
+        current_time = qemu_clock_get_ms(QEMU_CLOCK_HOST);
+        if (current_time - checkpoint_time < CHECKPOINT_MAX_PEROID) {
+            g_usleep(100000);
+            continue;
+        }
         /* start a colo checkpoint */
         ret = colo_do_checkpoint_transaction(s, buffer);
         if (ret < 0) {
             goto out;
         }
+        checkpoint_time = qemu_clock_get_ms(QEMU_CLOCK_HOST);
     }
 
 out:
-- 
1.8.3.1