qemu-patch-raspberry4/migration/migration.h
Peter Xu c788ada816 migration: add "return-path" capability
When this capability is enabled, QEMU will use the return path even for
precopy migration. This is helpful at least in one case when destination
failed to load the image while source quited without confirmation. With
return path, source will wait for the last response from destination,
and if destination fails, it'll fail the migration on source, then the
guest can be run again on the source (rather than assuming to be good,
then the guest will be lost after source quits).

It needs to be enabled explicitly on source, otherwise disabled.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1498472935-14461-1-git-send-email-peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-06-28 11:51:10 +02:00

197 lines
5.4 KiB
C

/*
* QEMU live migration
*
* 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 QEMU_MIGRATION_H
#define QEMU_MIGRATION_H
#include "qemu-common.h"
#include "qemu/thread.h"
#include "qapi-types.h"
#include "exec/cpu-common.h"
#include "qemu/coroutine_int.h"
#include "hw/qdev.h"
/* State for the incoming migration */
struct MigrationIncomingState {
QEMUFile *from_src_file;
/*
* Free at the start of the main state load, set as the main thread finishes
* loading state.
*/
QemuEvent main_thread_load_event;
size_t largest_page_size;
bool have_fault_thread;
QemuThread fault_thread;
QemuSemaphore fault_thread_sem;
bool have_listen_thread;
QemuThread listen_thread;
QemuSemaphore listen_thread_sem;
/* For the kernel to send us notifications */
int userfault_fd;
/* To tell the fault_thread to quit */
int userfault_quit_fd;
QEMUFile *to_src_file;
QemuMutex rp_mutex; /* We send replies from multiple threads */
void *postcopy_tmp_page;
void *postcopy_tmp_zero_page;
QEMUBH *bh;
int state;
bool have_colo_incoming_thread;
QemuThread colo_incoming_thread;
/* The coroutine we should enter (back) after failover */
Coroutine *migration_incoming_co;
QemuSemaphore colo_incoming_sem;
};
MigrationIncomingState *migration_incoming_get_current(void);
void migration_incoming_state_destroy(void);
#define TYPE_MIGRATION "migration"
#define MIGRATION_CLASS(klass) \
OBJECT_CLASS_CHECK(MigrationClass, (klass), TYPE_MIGRATION)
#define MIGRATION_OBJ(obj) \
OBJECT_CHECK(MigrationState, (obj), TYPE_MIGRATION)
#define MIGRATION_GET_CLASS(obj) \
OBJECT_GET_CLASS(MigrationClass, (obj), TYPE_MIGRATION)
typedef struct MigrationClass {
/*< private >*/
DeviceClass parent_class;
} MigrationClass;
struct MigrationState
{
/*< private >*/
DeviceState parent_obj;
/*< public >*/
size_t bytes_xfer;
size_t xfer_limit;
QemuThread thread;
QEMUBH *cleanup_bh;
QEMUFile *to_dst_file;
/* params from 'migrate-set-parameters' */
MigrationParameters parameters;
int state;
/* State related to return path */
struct {
QEMUFile *from_dst_file;
QemuThread rp_thread;
bool error;
} rp_state;
double mbps;
int64_t total_time;
int64_t downtime;
int64_t expected_downtime;
bool enabled_capabilities[MIGRATION_CAPABILITY__MAX];
int64_t xbzrle_cache_size;
int64_t setup_time;
/* Flag set once the migration has been asked to enter postcopy */
bool start_postcopy;
/* Flag set after postcopy has sent the device state */
bool postcopy_after_devices;
/* Flag set once the migration thread is running (and needs joining) */
bool migration_thread_running;
/* Flag set once the migration thread called bdrv_inactivate_all */
bool block_inactive;
/* The semaphore is used to notify COLO thread that failover is finished */
QemuSemaphore colo_exit_sem;
/* The semaphore is used to notify COLO thread to do checkpoint */
QemuSemaphore colo_checkpoint_sem;
int64_t colo_checkpoint_time;
QEMUTimer *colo_delay_timer;
/* The last error that occurred */
Error *error;
/* Do we have to clean up -b/-i from old migrate parameters */
/* This feature is deprecated and will be removed */
bool must_remove_block_options;
/*
* Global switch on whether we need to store the global state
* during migration.
*/
bool store_global_state;
/* Whether the VM is only allowing for migratable devices */
bool only_migratable;
/* Whether we send QEMU_VM_CONFIGURATION during migration */
bool send_configuration;
/* Whether we send section footer during migration */
bool send_section_footer;
};
void migrate_set_state(int *state, int old_state, int new_state);
void migration_fd_process_incoming(QEMUFile *f);
uint64_t migrate_max_downtime(void);
void migrate_fd_error(MigrationState *s, const Error *error);
void migrate_fd_connect(MigrationState *s);
MigrationState *migrate_init(void);
bool migration_is_blocked(Error **errp);
/* True if outgoing migration has entered postcopy phase */
bool migration_in_postcopy(void);
MigrationState *migrate_get_current(void);
bool migrate_release_ram(void);
bool migrate_postcopy_ram(void);
bool migrate_zero_blocks(void);
bool migrate_auto_converge(void);
int migrate_use_xbzrle(void);
int64_t migrate_xbzrle_cache_size(void);
bool migrate_colo_enabled(void);
bool migrate_use_block(void);
bool migrate_use_block_incremental(void);
bool migrate_use_return_path(void);
bool migrate_use_compression(void);
int migrate_compress_level(void);
int migrate_compress_threads(void);
int migrate_decompress_threads(void);
bool migrate_use_events(void);
/* Sending on the return path - generic and then for each message type */
void migrate_send_rp_shut(MigrationIncomingState *mis,
uint32_t value);
void migrate_send_rp_pong(MigrationIncomingState *mis,
uint32_t value);
void migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname,
ram_addr_t start, size_t len);
#endif