migration: expose the bitmap_sync_count to the end

expose the count that logs the times of updating the dirty bitmap to
end user.

Signed-off-by: ChenLiang <chenliang88@huawei.com>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

arch_init.c

@@ -537,6 +537,7 @@ static void migration_bitmap_sync(void)
         s->dirty_bytes_rate = s->dirty_pages_rate * TARGET_PAGE_SIZE;
         start_time = end_time;
         num_dirty_pages_period = 0;
+        s->dirty_sync_count = bitmap_sync_count;
     }
 }
 

hmp.c

@@ -188,6 +188,8 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
                        info->ram->normal);
         monitor_printf(mon, "normal bytes: %" PRIu64 " kbytes\n",
                        info->ram->normal_bytes >> 10);
+        monitor_printf(mon, "dirty sync count: %" PRIu64 "\n",
+                       info->ram->dirty_sync_count);
         if (info->ram->dirty_pages_rate) {
             monitor_printf(mon, "dirty pages rate: %" PRIu64 " pages\n",
                            info->ram->dirty_pages_rate);

include/migration/migration.h

@@ -61,6 +61,7 @@ struct MigrationState
     bool enabled_capabilities[MIGRATION_CAPABILITY_MAX];
     int64_t xbzrle_cache_size;
     int64_t setup_time;
+    int64_t dirty_sync_count;
 };
 
 void process_incoming_migration(QEMUFile *f);

migration.c

@@ -215,6 +215,7 @@ MigrationInfo *qmp_query_migrate(Error **errp)
         info->ram->normal_bytes = norm_mig_bytes_transferred();
         info->ram->dirty_pages_rate = s->dirty_pages_rate;
         info->ram->mbps = s->mbps;
+        info->ram->dirty_sync_count = s->dirty_sync_count;
 
         if (blk_mig_active()) {
             info->has_disk = true;
@@ -248,6 +249,7 @@ MigrationInfo *qmp_query_migrate(Error **errp)
         info->ram->normal = norm_mig_pages_transferred();
         info->ram->normal_bytes = norm_mig_bytes_transferred();
         info->ram->mbps = s->mbps;
+        info->ram->dirty_sync_count = s->dirty_sync_count;
         break;
     case MIG_STATE_ERROR:
         info->has_status = true;

qapi-schema.json

@@ -651,13 +651,15 @@
 #
 # @mbps: throughput in megabits/sec. (since 1.6)
 #
+# @dirty-sync-count: number of times that dirty ram was synchronized (since 2.1)
+#
 # Since: 0.14.0
 ##
 { 'type': 'MigrationStats',
   'data': {'transferred': 'int', 'remaining': 'int', 'total': 'int' ,
            'duplicate': 'int', 'skipped': 'int', 'normal': 'int',
            'normal-bytes': 'int', 'dirty-pages-rate' : 'int',
-           'mbps' : 'number' } }
+           'mbps' : 'number', 'dirty-sync-count' : 'int' } }
 
 ##
 # @XBZRLECacheStats

qmp-commands.hx

@@ -2967,6 +2967,7 @@ The main json-object contains the following:
             pages. This is just normal pages times size of one page,
             but this way upper levels don't need to care about page
             size (json-int)
+         - "dirty-sync-count": times that dirty ram was synchronized (json-int)
 - "disk": only present if "status" is "active" and it is a block migration,
   it is a json-object with the following disk information:
          - "transferred": amount transferred in bytes (json-int)
@@ -3004,7 +3005,8 @@ Examples:
           "downtime":12345,
           "duplicate":123,
           "normal":123,
-          "normal-bytes":123456
+          "normal-bytes":123456,
+          "dirty-sync-count":15
         }
      }
    }
@@ -3029,7 +3031,8 @@ Examples:
             "expected-downtime":12345,
             "duplicate":123,
             "normal":123,
-            "normal-bytes":123456
+            "normal-bytes":123456,
+            "dirty-sync-count":15
          }
       }
    }
@@ -3049,7 +3052,8 @@ Examples:
             "expected-downtime":12345,
             "duplicate":123,
             "normal":123,
-            "normal-bytes":123456
+            "normal-bytes":123456,
+            "dirty-sync-count":15
          },
          "disk":{
             "total":20971520,
@@ -3075,7 +3079,8 @@ Examples:
             "expected-downtime":12345,
             "duplicate":10,
             "normal":3333,
-            "normal-bytes":3412992
+            "normal-bytes":3412992,
+            "dirty-sync-count":15
          },
          "xbzrle-cache":{
             "cache-size":67108864,