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-rw-r--r--migration/migration.c2
-rw-r--r--migration/migration.h7
-rw-r--r--migration/ram.c7
3 files changed, 16 insertions, 0 deletions
diff --git a/migration/migration.c b/migration/migration.c
index 427d4de185..864164ad96 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -4363,6 +4363,8 @@ static Property migration_properties[] = {
     DEFINE_PROP_SIZE("announce-step", MigrationState,
                       parameters.announce_step,
                       DEFAULT_MIGRATE_ANNOUNCE_STEP),
+    DEFINE_PROP_BOOL("x-postcopy-preempt-break-huge", MigrationState,
+                      postcopy_preempt_break_huge, true),
 
     /* Migration capabilities */
     DEFINE_PROP_MIG_CAP("x-xbzrle", MIGRATION_CAPABILITY_XBZRLE),
diff --git a/migration/migration.h b/migration/migration.h
index ae4ffd3454..cdad8aceaa 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -340,6 +340,13 @@ struct MigrationState {
     bool send_configuration;
     /* Whether we send section footer during migration */
     bool send_section_footer;
+    /*
+     * Whether we allow break sending huge pages when postcopy preempt is
+     * enabled.  When disabled, we won't interrupt precopy within sending a
+     * host huge page, which is the old behavior of vanilla postcopy.
+     * NOTE: this parameter is ignored if postcopy preempt is not enabled.
+     */
+    bool postcopy_preempt_break_huge;
 
     /* Needed by postcopy-pause state */
     QemuSemaphore postcopy_pause_sem;
diff --git a/migration/ram.c b/migration/ram.c
index 65b08c4edb..7cbe9c310d 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -2266,11 +2266,18 @@ static int ram_save_target_page(RAMState *rs, PageSearchStatus *pss)
 
 static bool postcopy_needs_preempt(RAMState *rs, PageSearchStatus *pss)
 {
+    MigrationState *ms = migrate_get_current();
+
     /* Not enabled eager preempt?  Then never do that. */
     if (!migrate_postcopy_preempt()) {
         return false;
     }
 
+    /* If the user explicitly disabled breaking of huge page, skip */
+    if (!ms->postcopy_preempt_break_huge) {
+        return false;
+    }
+
     /* If the ramblock we're sending is a small page?  Never bother. */
     if (qemu_ram_pagesize(pss->block) == TARGET_PAGE_SIZE) {
         return false;