qemu/include/migration/misc.h
David Hildenbrand 1a37352277 migrate/ram: remove "ram_bulk_stage" and "fpo_enabled"
The bulk stage is kind of weird: migration_bitmap_find_dirty() will
indicate a dirty page, however, ram_save_host_page() will never save it, as
migration_bitmap_clear_dirty() detects that it is not dirty.

We already fill the bitmap in ram_list_init_bitmaps() with ones, marking
everything dirty - it didn't used to be that way, which is why we needed
an explicit first bulk stage.

Let's simplify: make the bitmap the single source of thuth. Explicitly
handle the "xbzrle_enabled after first round" case.

Regarding XBZRLE (implicitly handled via "ram_bulk_stage = false" right
now), there is now a slight change in behavior:
- Colo: When starting, it will be disabled (was implicitly enabled)
  until the first round actually finishes.
- Free page hinting: When starting, XBZRLE will be disabled (was implicitly
  enabled) until the first round actually finished.
- Snapshots: When starting, XBZRLE will be disabled. We essentially only
  do a single run, so I guess it will never actually get disabled.

Postcopy seems to indirectly disable it in ram_save_page(), so there
shouldn't be really any change.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210216105039.40680-1-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-13 18:21:13 +01:00

79 lines
2.1 KiB
C

/*
* QEMU migration miscellaneus exported functions
*
* Copyright IBM, Corp. 2008
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#ifndef MIGRATION_MISC_H
#define MIGRATION_MISC_H
#include "qemu/notify.h"
#include "qapi/qapi-types-net.h"
/* migration/ram.c */
typedef enum PrecopyNotifyReason {
PRECOPY_NOTIFY_SETUP = 0,
PRECOPY_NOTIFY_BEFORE_BITMAP_SYNC = 1,
PRECOPY_NOTIFY_AFTER_BITMAP_SYNC = 2,
PRECOPY_NOTIFY_COMPLETE = 3,
PRECOPY_NOTIFY_CLEANUP = 4,
PRECOPY_NOTIFY_MAX = 5,
} PrecopyNotifyReason;
typedef struct PrecopyNotifyData {
enum PrecopyNotifyReason reason;
Error **errp;
} PrecopyNotifyData;
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 ram_mig_init(void);
void qemu_guest_free_page_hint(void *addr, size_t len);
/* migration/block.c */
#ifdef CONFIG_LIVE_BLOCK_MIGRATION
void blk_mig_init(void);
#else
static inline void blk_mig_init(void) {}
#endif
AnnounceParameters *migrate_announce_params(void);
/* migration/savevm.c */
void dump_vmstate_json_to_file(FILE *out_fp);
/* migration/migration.c */
void migration_object_init(void);
void migration_shutdown(void);
bool migration_is_idle(void);
bool migration_is_active(MigrationState *);
void add_migration_state_change_notifier(Notifier *notify);
void remove_migration_state_change_notifier(Notifier *notify);
bool migration_in_setup(MigrationState *);
bool migration_has_finished(MigrationState *);
bool migration_has_failed(MigrationState *);
/* ...and after the device transmission */
bool migration_in_postcopy_after_devices(MigrationState *);
void migration_global_dump(Monitor *mon);
/* True if incomming migration entered POSTCOPY_INCOMING_DISCARD */
bool migration_in_incoming_postcopy(void);
/* True if background snapshot is active */
bool migration_in_bg_snapshot(void);
/* migration/block-dirty-bitmap.c */
void dirty_bitmap_mig_init(void);
#endif