migration: Use atomic ops properly for page accountings

To prepare for thread-safety on page accountings, at least below counters
need to be accessed only atomically, they are:

        ram_counters.transferred
        ram_counters.duplicate
        ram_counters.normal
        ram_counters.postcopy_bytes

There are a lot of other counters but they won't be accessed outside
migration thread, then they're still safe to be accessed without atomic
ops.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

1 files changed, 5 insertions, 5 deletions

diff --git a/migration/migration.c b/migration/migration.c
index f485eea5fb..de83c50f51 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1049,13 +1049,13 @@ static void populate_ram_info(MigrationInfo *info, MigrationState *s)
 
     info->has_ram = true;
     info->ram = g_malloc0(sizeof(*info->ram));
-    info->ram->transferred = ram_counters.transferred;
+    info->ram->transferred = stat64_get(&ram_atomic_counters.transferred);
     info->ram->total = ram_bytes_total();
-    info->ram->duplicate = ram_counters.duplicate;
+    info->ram->duplicate = stat64_get(&ram_atomic_counters.duplicate);
     /* legacy value.  It is not used anymore */
     info->ram->skipped = 0;
-    info->ram->normal = ram_counters.normal;
-    info->ram->normal_bytes = ram_counters.normal * page_size;
+    info->ram->normal = stat64_get(&ram_atomic_counters.normal);
+    info->ram->normal_bytes = info->ram->normal * page_size;
     info->ram->mbps = s->mbps;
     info->ram->dirty_sync_count = ram_counters.dirty_sync_count;
     info->ram->dirty_sync_missed_zero_copy =
@@ -1066,7 +1066,7 @@ static void populate_ram_info(MigrationInfo *info, MigrationState *s)
     info->ram->pages_per_second = s->pages_per_second;
     info->ram->precopy_bytes = ram_counters.precopy_bytes;
     info->ram->downtime_bytes = ram_counters.downtime_bytes;
-    info->ram->postcopy_bytes = ram_counters.postcopy_bytes;
+    info->ram->postcopy_bytes = stat64_get(&ram_atomic_counters.postcopy_bytes);
 
     if (migrate_use_xbzrle()) {
         info->has_xbzrle_cache = true;