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;