migration/migration.h

   1 /*
   2  * QEMU live migration
   3  *
   4  * Copyright IBM, Corp. 2008
   5  *
   6  * Authors:
   7  *  Anthony Liguori   <aliguori@us.ibm.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2.  See
  10  * the COPYING file in the top-level directory.
  11  *
  12  */
  13
  14 #ifndef QEMU_MIGRATION_H
  15 #define QEMU_MIGRATION_H
  16
  17 #include "qemu-common.h"
  18 #include "qapi/qapi-types-migration.h"
  19 #include "qemu/thread.h"
  20 #include "exec/cpu-common.h"
  21 #include "qemu/coroutine_int.h"
  22 #include "hw/qdev.h"
  23 #include "io/channel.h"
  24
  25 struct PostcopyBlocktimeContext;
  26
  27 #define  MIGRATION_RESUME_ACK_VALUE  (1)
  28
  29 /* State for the incoming migration */
  30 struct MigrationIncomingState {
  31     QEMUFile *from_src_file;
  32
  33     /*
  34      * Free at the start of the main state load, set as the main thread finishes
  35      * loading state.
  36      */
  37     QemuEvent main_thread_load_event;
  38
  39     size_t         largest_page_size;
  40     bool           have_fault_thread;
  41     QemuThread     fault_thread;
  42     QemuSemaphore  fault_thread_sem;
  43     /* Set this when we want the fault thread to quit */
  44     bool           fault_thread_quit;
  45
  46     bool           have_listen_thread;
  47     QemuThread     listen_thread;
  48     QemuSemaphore  listen_thread_sem;
  49
  50     /* For the kernel to send us notifications */
  51     int       userfault_fd;
  52     /* To notify the fault_thread to wake, e.g., when need to quit */
  53     int       userfault_event_fd;
  54     QEMUFile *to_src_file;
  55     QemuMutex rp_mutex;    /* We send replies from multiple threads */
  56     /* RAMBlock of last request sent to source */
  57     RAMBlock *last_rb;
  58     void     *postcopy_tmp_page;
  59     void     *postcopy_tmp_zero_page;
  60     /* PostCopyFD's for external userfaultfds & handlers of shared memory */
  61     GArray   *postcopy_remote_fds;
  62
  63     QEMUBH *bh;
  64
  65     int state;
  66
  67     bool have_colo_incoming_thread;
  68     QemuThread colo_incoming_thread;
  69     /* The coroutine we should enter (back) after failover */
  70     Coroutine *migration_incoming_co;
  71     QemuSemaphore colo_incoming_sem;
  72
  73     /*
  74      * PostcopyBlocktimeContext to keep information for postcopy
  75      * live migration, to calculate vCPU block time
  76      * */
  77     struct PostcopyBlocktimeContext *blocktime_ctx;
  78
  79     /* notify PAUSED postcopy incoming migrations to try to continue */
  80     bool postcopy_recover_triggered;
  81     QemuSemaphore postcopy_pause_sem_dst;
  82     QemuSemaphore postcopy_pause_sem_fault;
  83 };
  84
  85 MigrationIncomingState *migration_incoming_get_current(void);
  86 void migration_incoming_state_destroy(void);
  87 /*
  88  * Functions to work with blocktime context
  89  */
  90 void fill_destination_postcopy_migration_info(MigrationInfo *info);
  91
  92 #define TYPE_MIGRATION "migration"
  93
  94 #define MIGRATION_CLASS(klass) \
  95     OBJECT_CLASS_CHECK(MigrationClass, (klass), TYPE_MIGRATION)
  96 #define MIGRATION_OBJ(obj) \
  97     OBJECT_CHECK(MigrationState, (obj), TYPE_MIGRATION)
  98 #define MIGRATION_GET_CLASS(obj) \
  99     OBJECT_GET_CLASS(MigrationClass, (obj), TYPE_MIGRATION)
 100
 101 typedef struct MigrationClass {
 102     /*< private >*/
 103     DeviceClass parent_class;
 104 } MigrationClass;
 105
 106 struct MigrationState
 107 {
 108     /*< private >*/
 109     DeviceState parent_obj;
 110
 111     /*< public >*/
 112     size_t bytes_xfer;
 113     size_t xfer_limit;
 114     QemuThread thread;
 115     QEMUBH *cleanup_bh;
 116     QEMUFile *to_dst_file;
 117     /*
 118      * Protects to_dst_file pointer.  We need to make sure we won't
 119      * yield or hang during the critical section, since this lock will
 120      * be used in OOB command handler.
 121      */
 122     QemuMutex qemu_file_lock;
 123
 124     /* bytes already send at the beggining of current interation */
 125     uint64_t iteration_initial_bytes;
 126     /* time at the start of current iteration */
 127     int64_t iteration_start_time;
 128     /*
 129      * The final stage happens when the remaining data is smaller than
 130      * this threshold; it's calculated from the requested downtime and
 131      * measured bandwidth
 132      */
 133     int64_t threshold_size;
 134
 135     /* params from 'migrate-set-parameters' */
 136     MigrationParameters parameters;
 137
 138     int state;
 139
 140     /* State related to return path */
 141     struct {
 142         QEMUFile     *from_dst_file;
 143         QemuThread    rp_thread;
 144         bool          error;
 145         QemuSemaphore rp_sem;
 146     } rp_state;
 147
 148     double mbps;
 149     /* Timestamp when recent migration starts (ms) */
 150     int64_t start_time;
 151     /* Total time used by latest migration (ms) */
 152     int64_t total_time;
 153     /* Timestamp when VM is down (ms) to migrate the last stuff */
 154     int64_t downtime_start;
 155     int64_t downtime;
 156     int64_t expected_downtime;
 157     bool enabled_capabilities[MIGRATION_CAPABILITY__MAX];
 158     int64_t setup_time;
 159     /*
 160      * Whether guest was running when we enter the completion stage.
 161      * If migration is interrupted by any reason, we need to continue
 162      * running the guest on source.
 163      */
 164     bool vm_was_running;
 165
 166     /* Flag set once the migration has been asked to enter postcopy */
 167     bool start_postcopy;
 168     /* Flag set after postcopy has sent the device state */
 169     bool postcopy_after_devices;
 170
 171     /* Flag set once the migration thread is running (and needs joining) */
 172     bool migration_thread_running;
 173
 174     /* Flag set once the migration thread called bdrv_inactivate_all */
 175     bool block_inactive;
 176
 177     /* Migration is paused due to pause-before-switchover */
 178     QemuSemaphore pause_sem;
 179
 180     /* The semaphore is used to notify COLO thread that failover is finished */
 181     QemuSemaphore colo_exit_sem;
 182
 183     /* The semaphore is used to notify COLO thread to do checkpoint */
 184     QemuSemaphore colo_checkpoint_sem;
 185     int64_t colo_checkpoint_time;
 186     QEMUTimer *colo_delay_timer;
 187
 188     /* The first error that has occurred.
 189        We used the mutex to be able to return the 1st error message */
 190     Error *error;
 191     /* mutex to protect errp */
 192     QemuMutex error_mutex;
 193
 194     /* Do we have to clean up -b/-i from old migrate parameters */
 195     /* This feature is deprecated and will be removed */
 196     bool must_remove_block_options;
 197
 198     /*
 199      * Global switch on whether we need to store the global state
 200      * during migration.
 201      */
 202     bool store_global_state;
 203
 204     /* Whether the VM is only allowing for migratable devices */
 205     bool only_migratable;
 206
 207     /* Whether we send QEMU_VM_CONFIGURATION during migration */
 208     bool send_configuration;
 209     /* Whether we send section footer during migration */
 210     bool send_section_footer;
 211
 212     /* Needed by postcopy-pause state */
 213     QemuSemaphore postcopy_pause_sem;
 214     QemuSemaphore postcopy_pause_rp_sem;
 215     /*
 216      * Whether we abort the migration if decompression errors are
 217      * detected at the destination. It is left at false for qemu
 218      * older than 3.0, since only newer qemu sends streams that
 219      * do not trigger spurious decompression errors.
 220      */
 221     bool decompress_error_check;
 222 };
 223
 224 void migrate_set_state(int *state, int old_state, int new_state);
 225
 226 void migration_fd_process_incoming(QEMUFile *f);
 227 void migration_ioc_process_incoming(QIOChannel *ioc);
 228 void migration_incoming_process(void);
 229
 230 bool  migration_has_all_channels(void);
 231
 232 uint64_t migrate_max_downtime(void);
 233
 234 void migrate_set_error(MigrationState *s, const Error *error);
 235 void migrate_fd_error(MigrationState *s, const Error *error);
 236
 237 void migrate_fd_connect(MigrationState *s, Error *error_in);
 238
 239 void migrate_init(MigrationState *s);
 240 bool migration_is_blocked(Error **errp);
 241 /* True if outgoing migration has entered postcopy phase */
 242 bool migration_in_postcopy(void);
 243 MigrationState *migrate_get_current(void);
 244
 245 bool migrate_postcopy(void);
 246
 247 bool migrate_release_ram(void);
 248 bool migrate_postcopy_ram(void);
 249 bool migrate_zero_blocks(void);
 250 bool migrate_dirty_bitmaps(void);
 251
 252 bool migrate_auto_converge(void);
 253 bool migrate_use_multifd(void);
 254 bool migrate_pause_before_switchover(void);
 255 int migrate_multifd_channels(void);
 256 int migrate_multifd_page_count(void);
 257
 258 int migrate_use_xbzrle(void);
 259 int64_t migrate_xbzrle_cache_size(void);
 260 bool migrate_colo_enabled(void);
 261
 262 bool migrate_use_block(void);
 263 bool migrate_use_block_incremental(void);
 264 bool migrate_use_return_path(void);
 265
 266 bool migrate_use_compression(void);
 267 int migrate_compress_level(void);
 268 int migrate_compress_threads(void);
 269 int migrate_decompress_threads(void);
 270 bool migrate_use_events(void);
 271 bool migrate_postcopy_blocktime(void);
 272
 273 /* Sending on the return path - generic and then for each message type */
 274 void migrate_send_rp_shut(MigrationIncomingState *mis,
 275                           uint32_t value);
 276 void migrate_send_rp_pong(MigrationIncomingState *mis,
 277                           uint32_t value);
 278 int migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname,
 279                               ram_addr_t start, size_t len);
 280 void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis,
 281                                  char *block_name);
 282 void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value);
 283
 284 void dirty_bitmap_mig_before_vm_start(void);
 285 void init_dirty_bitmap_incoming_migration(void);
 286
 287 #define qemu_ram_foreach_block \
 288   #warning "Use qemu_ram_foreach_block_migratable in migration code"
 289
 290 #endif