When the host page is a huge page and something is sent in the
current iteration, the migration_rate_limit() should be executed.
If not, this function can be omitted to save time.
Rename tmppages to pages_this_iteration to express its meaning
more clearly.
Signed-off-by: Keqian Zhu <zhukeqi...@huawei.com>
Signed-off-by: Kunkun Jiang <jiangkun...@huawei.com>
---
migration/ram.c | 21 ++++++++++++++-------
1 file changed, 14 insertions(+), 7 deletions(-)
diff --git a/migration/ram.c b/migration/ram.c
index a168da5cdd..9fc5b2997c 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -1988,7 +1988,7 @@ static int ram_save_target_page(RAMState *rs,
PageSearchStatus *pss,
static int ram_save_host_page(RAMState *rs, PageSearchStatus *pss,
bool last_stage)
{
- int tmppages, pages = 0;
+ int pages = 0;
size_t pagesize_bits =
qemu_ram_pagesize(pss->block) >> TARGET_PAGE_BITS;
unsigned long start_page = pss->page;
@@ -2000,21 +2000,28 @@ static int ram_save_host_page(RAMState *rs,
PageSearchStatus *pss,
}
do {
+ int pages_this_iteration = 0;
+
/* Check if the page is dirty and send it if it is */
if (!migration_bitmap_clear_dirty(rs, pss->block, pss->page)) {
pss->page++;
continue;
}
- tmppages = ram_save_target_page(rs, pss, last_stage);
- if (tmppages < 0) {
- return tmppages;
+ pages_this_iteration = ram_save_target_page(rs, pss, last_stage);
+ if (pages_this_iteration < 0) {
+ return pages_this_iteration;
}
- pages += tmppages;
+ pages += pages_this_iteration;
pss->page++;
- /* Allow rate limiting to happen in the middle of huge pages */
- migration_rate_limit();
+ /*
+ * Allow rate limiting to happen in the middle of huge pages if
+ * something is sent in the current iteration.
+ */
+ if (pagesize_bits > 1 && pages_this_iteration > 0) {
+ migration_rate_limit();
+ }
} while ((pss->page & (pagesize_bits - 1)) &&
offset_in_ramblock(pss->block,
((ram_addr_t)pss->page) << TARGET_PAGE_BITS));
--
2.23.0
