Add migration accounting for normal and duplicate pages

Signed-off-by: Benoit Hudzia <benoit.hudzia@sap.com>
Signed-off-by: Petter Svard <petters@cs.umu.se>
Signed-off-by: Aidan Shribman <aidan.shribman@sap.com>
Signed-off-by: Orit Wasserman <owasserm@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

arch_init.c

@@ -201,6 +201,40 @@ int64_t xbzrle_cache_resize(int64_t new_size)
     return pow2floor(new_size);
 }
 
+/* accounting for migration statistics */
+typedef struct AccountingInfo {
+    uint64_t dup_pages;
+    uint64_t norm_pages;
+    uint64_t iterations;
+} AccountingInfo;
+
+static AccountingInfo acct_info;
+
+static void acct_clear(void)
+{
+    memset(&acct_info, 0, sizeof(acct_info));
+}
+
+uint64_t dup_mig_bytes_transferred(void)
+{
+    return acct_info.dup_pages * TARGET_PAGE_SIZE;
+}
+
+uint64_t dup_mig_pages_transferred(void)
+{
+    return acct_info.dup_pages;
+}
+
+uint64_t norm_mig_bytes_transferred(void)
+{
+    return acct_info.norm_pages * TARGET_PAGE_SIZE;
+}
+
+uint64_t norm_mig_pages_transferred(void)
+{
+    return acct_info.norm_pages;
+}
+
 static void save_block_hdr(QEMUFile *f, RAMBlock *block, ram_addr_t offset,
         int cont, int flag)
 {
@@ -295,6 +329,7 @@ static int ram_save_block(QEMUFile *f)
             p = memory_region_get_ram_ptr(mr) + offset;
 
             if (is_dup_page(p)) {
+                acct_info.dup_pages++;
                 save_block_hdr(f, block, offset, cont, RAM_SAVE_FLAG_COMPRESS);
                 qemu_put_byte(f, *p);
                 bytes_sent = 1;
@@ -310,6 +345,7 @@ static int ram_save_block(QEMUFile *f)
                 save_block_hdr(f, block, offset, cont, RAM_SAVE_FLAG_PAGE);
                 qemu_put_buffer(f, p, TARGET_PAGE_SIZE);
                 bytes_sent = TARGET_PAGE_SIZE;
+                acct_info.norm_pages++;
             }
 
             /* if page is unmodified, continue to the next */
@@ -431,6 +467,7 @@ static int ram_save_setup(QEMUFile *f, void *opaque)
         }
         XBZRLE.encoded_buf = g_malloc0(TARGET_PAGE_SIZE);
         XBZRLE.current_buf = g_malloc(TARGET_PAGE_SIZE);
+        acct_clear();
     }
 
     /* Make sure all dirty bits are set */
@@ -479,6 +516,7 @@ static int ram_save_iterate(QEMUFile *f, void *opaque)
             break;
         }
         bytes_transferred += bytes_sent;
+        acct_info.iterations++;
         /* we want to check in the 1st loop, just in case it was the 1st time
            and we had to sync the dirty bitmap.
            qemu_get_clock_ns() is a bit expensive, so we only check each some

hmp.c

@@ -160,6 +160,12 @@ void hmp_info_migrate(Monitor *mon)
                        info->ram->total >> 10);
         monitor_printf(mon, "total time: %" PRIu64 " milliseconds\n",
                        info->ram->total_time);
+        monitor_printf(mon, "duplicate: %" PRIu64 " pages\n",
+                       info->ram->duplicate);
+        monitor_printf(mon, "normal: %" PRIu64 " pages\n",
+                       info->ram->normal);
+        monitor_printf(mon, "normal bytes: %" PRIu64 " kbytes\n",
+                       info->ram->normal_bytes >> 10);
     }
 
     if (info->has_disk) {

migration.c

@@ -161,6 +161,9 @@ MigrationInfo *qmp_query_migrate(Error **errp)
         info->ram->total = ram_bytes_total();
         info->ram->total_time = qemu_get_clock_ms(rt_clock)
             - s->total_time;
+        info->ram->duplicate = dup_mig_pages_transferred();
+        info->ram->normal = norm_mig_pages_transferred();
+        info->ram->normal_bytes = norm_mig_bytes_transferred();
 
         if (blk_mig_active()) {
             info->has_disk = true;
@@ -180,6 +183,9 @@ MigrationInfo *qmp_query_migrate(Error **errp)
         info->ram->remaining = 0;
         info->ram->total = ram_bytes_total();
         info->ram->total_time = s->total_time;
+        info->ram->duplicate = dup_mig_pages_transferred();
+        info->ram->normal = norm_mig_pages_transferred();
+        info->ram->normal_bytes = norm_mig_bytes_transferred();
         break;
     case MIG_STATE_ERROR:
         info->has_status = true;

migration.h

@@ -87,6 +87,11 @@ uint64_t ram_bytes_total(void);
 
 extern SaveVMHandlers savevm_ram_handlers;
 
+uint64_t dup_mig_bytes_transferred(void);
+uint64_t dup_mig_pages_transferred(void);
+uint64_t norm_mig_bytes_transferred(void);
+uint64_t norm_mig_pages_transferred(void);
+
 /**
  * @migrate_add_blocker - prevent migration from proceeding
  *

qapi-schema.json

@@ -264,11 +264,18 @@
 #        migration has ended, it returns the total migration
 #        time. (since 1.2)
 #
-# Since: 0.14.0.
+# @duplicate: number of duplicate pages (since 1.2)
+#
+# @normal : number of normal pages (since 1.2)
+#
+# @normal-bytes : number of normal bytes sent (since 1.2)
+#
+# Since: 0.14.0
 ##
 { 'type': 'MigrationStats',
   'data': {'transferred': 'int', 'remaining': 'int', 'total': 'int' ,
-           'total-time': 'int' } }
+           'total-time': 'int', 'duplicate': 'int', 'normal': 'int',
+           'normal-bytes': 'int' } }
 
 ##
 # @MigrationInfo

qmp-commands.hx

@@ -2125,6 +2125,9 @@ The main json-object contains the following:
          - "total-time": total amount of ms since migration started.  If
                          migration has ended, it returns the total migration time
                          (json-int)
+         - "duplicate": number of duplicated pages (json-int)
+         - "normal" : number of normal pages transferred (json-int)
+         - "normal-bytes" : number of normal bytes transferred (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 (in bytes):
          - "transferred": amount transferred (json-int)
@@ -2141,7 +2144,19 @@ Examples:
 2. Migration is done and has succeeded
 
 -> { "execute": "query-migrate" }
-<- { "return": { "status": "completed" } }
+<- { "return": {
+        "status": "completed",
+        "ram":{
+          "transferred":123,
+          "remaining":123,
+          "total":246,
+          "total-time":12345,
+          "duplicate":123,
+          "normal":123,
+          "normal-bytes":123456
+        }
+     }
+   }
 
 3. Migration is done and has failed
 
@@ -2158,7 +2173,10 @@ Examples:
             "transferred":123,
             "remaining":123,
             "total":246,
-            "total-time":12345
+            "total-time":12345,
+            "duplicate":123,
+            "normal":123,
+            "normal-bytes":123456
          }
       }
    }
@@ -2173,7 +2191,10 @@ Examples:
             "total":1057024,
             "remaining":1053304,
             "transferred":3720,
-            "total-time":12345
+            "total-time":12345,
+            "duplicate":123,
+            "normal":123,
+            "normal-bytes":123456
          },
          "disk":{
             "total":20971520,