Patchwork [09/11] Add migration accounting for normal and duplicate pages

diff --git a/arch_init.c b/arch_init.c
index 69a39cb..12afc46 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -205,6 +205,40 @@  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)
 {
@@ -307,6 +341,7 @@  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;
@@ -322,6 +357,7 @@  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 */
@@ -443,6 +479,7 @@  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();
     }

     QLIST_FOREACH(block, &ram_list.blocks, next) {
@@ -490,6 +527,7 @@  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
diff --git a/migration.c b/migration.c
index 9b0e1fa..cae444c 100644
--- a/migration.c
+++ b/migration.c
@@ -156,6 +156,8 @@  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();

         if (blk_mig_active()) {
             info->has_disk = true;
@@ -168,6 +170,14 @@  MigrationInfo *qmp_query_migrate(Error **errp)
     case MIG_STATE_COMPLETED:
         get_capabilities(s, info);

+        info->has_ram = true;
+        info->ram = g_malloc0(sizeof(*info->ram));
+        info->ram->transferred = ram_bytes_transferred();
+        info->ram->remaining = ram_bytes_remaining();
+        info->ram->total = ram_bytes_total();
+        info->ram->duplicate = dup_mig_pages_transferred();
+        info->ram->normal = norm_mig_pages_transferred();
+
         info->has_status = true;
         info->status = g_strdup("completed");

diff --git a/migration.h b/migration.h
index 337e225..e4a7cd7 100644
--- a/migration.h
+++ b/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
  *
diff --git a/qapi-schema.json b/qapi-schema.json
index 0b5ccae..8676c1d 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -264,11 +264,15 @@ 
 #        migration has ended, it returns the total migration
 #        time. (since 1.2)
 #
-# Since: 0.14.0.
+# @duplicate: #optional, number of duplicate pages (since 1.2)
+#
+# @normal : #optional, number of normal pages (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' } }

 ##
 # @MigrationInfo
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 4ea38bf..9a4bff0 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -2099,6 +2099,8 @@  The main json-object contains the following:
          - "transferred": amount transferred (json-int)
          - "remaining": amount remaining (json-int)
          - "total": total (json-int)
+	 - "duplicate": number of duplicated pages (json-int)
+	 - "normal" : number of normal pages 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)