migration/postcopy: set all_zero to true on the first target page

For the first target page, all_zero is set to true for this round check.

After target_pages introduced, we could leverage this variable instead
of checking the address offset.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

diff --git a/migration/ram.c b/migration/ram.c
index 8ebaea255ee8ed33bef838645b72b2bda15c440a..460abfa2c356e76f1361099aed766b3df9a6cfd1 100644 (file)
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -4102,7 +4102,7 @@ static int ram_load_postcopy(QEMUFile *f)
             page_buffer = postcopy_host_page +
                           ((uintptr_t)host & (block->page_size - 1));
             /* If all TP are zero then we can optimise the place */
-            if (!((uintptr_t)host & (block->page_size - 1))) {
+            if (target_pages == 1) {
                 all_zero = true;
             } else {
                 /* not the 1st TP within the HP */