diff options
| -rw-r--r-- | include/migration/misc.h | 1 | ||||
| -rw-r--r-- | migration/ram.c | 18 |
2 files changed, 18 insertions, 1 deletions
diff --git a/include/migration/misc.h b/include/migration/misc.h index dc46d3354f..5cdbabd094 100644 --- a/include/migration/misc.h +++ b/include/migration/misc.h @@ -38,6 +38,7 @@ void precopy_infrastructure_init(void); void precopy_add_notifier(NotifierWithReturn *n); void precopy_remove_notifier(NotifierWithReturn *n); int precopy_notify(PrecopyNotifyReason reason, Error **errp); +void precopy_enable_free_page_optimization(void); void ram_mig_init(void); void qemu_guest_free_page_hint(void *addr, size_t len); diff --git a/migration/ram.c b/migration/ram.c index bee4fb3fd4..35bd6213e9 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -316,6 +316,8 @@ struct RAMState { uint32_t last_version; /* We are in the first round */ bool ram_bulk_stage; + /* The free page optimization is enabled */ + bool fpo_enabled; /* How many times we have dirty too many pages */ int dirty_rate_high_cnt; /* these variables are used for bitmap sync */ @@ -380,6 +382,15 @@ int precopy_notify(PrecopyNotifyReason reason, Error **errp) return notifier_with_return_list_notify(&precopy_notifier_list, &pnd); } +void precopy_enable_free_page_optimization(void) +{ + if (!ram_state) { + return; + } + + ram_state->fpo_enabled = true; +} + uint64_t ram_bytes_remaining(void) { return ram_state ? (ram_state->migration_dirty_pages * TARGET_PAGE_SIZE) : @@ -1601,7 +1612,11 @@ unsigned long migration_bitmap_find_dirty(RAMState *rs, RAMBlock *rb, return size; } - if (rs->ram_bulk_stage && start > 0) { + /* + * When the free page optimization is enabled, we need to check the bitmap + * to send the non-free pages rather than all the pages in the bulk stage. + */ + if (!rs->fpo_enabled && rs->ram_bulk_stage && start > 0) { next = start + 1; } else { next = find_next_bit(bitmap, size, start); @@ -2651,6 +2666,7 @@ static void ram_state_reset(RAMState *rs) rs->last_page = 0; rs->last_version = ram_list.version; rs->ram_bulk_stage = true; + rs->fpo_enabled = false; } #define MAX_WAIT 50 /* ms, half buffered_file limit */ |