[PATCH v4 07/10] migration: Refactor auto-converge capability logic

[huangy81]

From: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>

Check if block migration is running before throttling
guest down in auto-converge way.

Note that this modification is kind of like code clean,
because block migration does not depend on auto-converge
capability, so the order of checks can be adjusted.

Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
Acked-by: Peter Xu <peterx@redhat.com>
---
 migration/ram.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/migration/ram.c b/migration/ram.c
index 521912385d..3e5dff4068 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -1200,7 +1200,11 @@ static void migration_trigger_throttle(RAMState *rs)
     /* During block migration the auto-converge logic incorrectly detects
      * that ram migration makes no progress. Avoid this by disabling the
      * throttling logic during the bulk phase of block migration. */
-    if (migrate_auto_converge() && !blk_mig_bulk_active()) {
+    if (blk_mig_bulk_active()) {
+        return;
+    }
+
+    if (migrate_auto_converge()) {
         /* The following detection logic can be refined later. For now:
            Check to see if the ratio between dirtied bytes and the approx.
            amount of bytes that just got transferred since the last time
-- 
2.17.1