During migration, we would sync bitmap from ram_list.dirty_memory to
RAMBlock.bmap in cpu_physical_memory_sync_dirty_bitmap().
Since we set RAMBlock.bmap and ram_list.dirty_memory both to all 1, this
means at the first round this sync is meaningless and is a duplicated
work.
Leaving RAMBlock->bmap blank on allocating would have a side effect on
migration_dirty_pages, since it is calculated from the result of
cpu_physical_memory_sync_dirty_bitmap(). To keep it right, we need to
set migration_dirty_pages to 0 in ram_state_init().
Signed-off-by: Wei Yang <richardw.y...@linux.intel.com>
---
migration/ram.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/migration/ram.c b/migration/ram.c
index 95c51109d2..417874707d 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -3151,12 +3151,7 @@ static int ram_state_init(RAMState **rsp)
qemu_mutex_init(&(*rsp)->src_page_req_mutex);
QSIMPLEQ_INIT(&(*rsp)->src_page_requests);
- /*
- * Count the total number of pages used by ram blocks not including any
- * gaps due to alignment or unplugs.
- */
- (*rsp)->migration_dirty_pages = ram_bytes_total() >> TARGET_PAGE_BITS;
-
+ (*rsp)->migration_dirty_pages = 0;
ram_state_reset(*rsp);
return 0;
@@ -3172,7 +3167,6 @@ static void ram_list_init_bitmaps(void)
RAMBLOCK_FOREACH_NOT_IGNORED(block) {
pages = block->max_length >> TARGET_PAGE_BITS;
block->bmap = bitmap_new(pages);
- bitmap_set(block->bmap, 0, pages);
if (migrate_postcopy_ram()) {
block->unsentmap = bitmap_new(pages);
bitmap_set(block->unsentmap, 0, pages);
--
2.19.1
