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 "exec/cpu-common.h"
  18 #include "hw/qdev-core.h"
  19 #include "qapi/qapi-types-migration.h"
  20 #include "qemu/thread.h"
  21 #include "qemu/coroutine_int.h"
  22 #include "io/channel.h"
  23 #include "net/announce.h"
  24 #include "qom/object.h"
  25
  26 struct PostcopyBlocktimeContext;
  27
  28 #define  MIGRATION_RESUME_ACK_VALUE  (1)
  29
  30 /*
  31  * 1<<6=64 pages -> 256K chunk when page size is 4K.  This gives us
  32  * the benefit that all the chunks are 64 pages aligned then the
  33  * bitmaps are always aligned to LONG.
  34  */
  35 #define CLEAR_BITMAP_SHIFT_MIN             6
  36 /*
  37  * 1<<18=256K pages -> 1G chunk when page size is 4K.  This is the
  38  * default value to use if no one specified.
  39  */
  40 #define CLEAR_BITMAP_SHIFT_DEFAULT        18
  41 /*
  42  * 1<<31=2G pages -> 8T chunk when page size is 4K.  This should be
  43  * big enough and make sure we won't overflow easily.
  44  */
  45 #define CLEAR_BITMAP_SHIFT_MAX            31
  46
  47 /* State for the incoming migration */
  48 struct MigrationIncomingState {
  49     QEMUFile *from_src_file;
  50
  51     /*
  52      * Free at the start of the main state load, set as the main thread finishes
  53      * loading state.
  54      */
  55     QemuEvent main_thread_load_event;
  56
  57     /* For network announces */
  58     AnnounceTimer  announce_timer;
  59
  60     size_t         largest_page_size;
  61     bool           have_fault_thread;
  62     QemuThread     fault_thread;
  63     QemuSemaphore  fault_thread_sem;
  64     /* Set this when we want the fault thread to quit */
  65     bool           fault_thread_quit;
  66
  67     bool           have_listen_thread;
  68     QemuThread     listen_thread;
  69     QemuSemaphore  listen_thread_sem;
  70
  71     /* For the kernel to send us notifications */
  72     int       userfault_fd;
  73     /* To notify the fault_thread to wake, e.g., when need to quit */
  74     int       userfault_event_fd;
  75     QEMUFile *to_src_file;
  76     QemuMutex rp_mutex;    /* We send replies from multiple threads */
  77     /* RAMBlock of last request sent to source */
  78     RAMBlock *last_rb;
  79     void     *postcopy_tmp_page;
  80     void     *postcopy_tmp_zero_page;
  81     /* PostCopyFD's for external userfaultfds & handlers of shared memory */
  82     GArray   *postcopy_remote_fds;
  83
  84     QEMUBH *bh;
  85
  86     int state;
  87
  88     bool have_colo_incoming_thread;
  89     QemuThread colo_incoming_thread;
  90     /* The coroutine we should enter (back) after failover */
  91     Coroutine *migration_incoming_co;
  92     QemuSemaphore colo_incoming_sem;
  93
  94     /*
  95      * PostcopyBlocktimeContext to keep information for postcopy
  96      * live migration, to calculate vCPU block time
  97      * */
  98     struct PostcopyBlocktimeContext *blocktime_ctx;
  99
 100     /* notify PAUSED postcopy incoming migrations to try to continue */
 101     bool postcopy_recover_triggered;
 102     QemuSemaphore postcopy_pause_sem_dst;
 103     QemuSemaphore postcopy_pause_sem_fault;
 104
 105     /* List of listening socket addresses  */
 106     SocketAddressList *socket_address_list;
 107 };
 108
 109 MigrationIncomingState *migration_incoming_get_current(void);
 110 void migration_incoming_state_destroy(void);
 111 /*
 112  * Functions to work with blocktime context
 113  */
 114 void fill_destination_postcopy_migration_info(MigrationInfo *info);
 115
 116 #define TYPE_MIGRATION "migration"
 117
 118 typedef struct MigrationClass MigrationClass;
 119 DECLARE_OBJ_CHECKERS(MigrationState, MigrationClass,
 120                      MIGRATION_OBJ, TYPE_MIGRATION)
 121
 122 struct MigrationClass {
 123     /*< private >*/
 124     DeviceClass parent_class;
 125 };
 126
 127 struct MigrationState
 128 {
 129     /*< private >*/
 130     DeviceState parent_obj;
 131
 132     /*< public >*/
 133     QemuThread thread;
 134     QEMUBH *cleanup_bh;
 135     QEMUFile *to_dst_file;
 136     /*
 137      * Protects to_dst_file pointer.  We need to make sure we won't
 138      * yield or hang during the critical section, since this lock will
 139      * be used in OOB command handler.
 140      */
 141     QemuMutex qemu_file_lock;
 142
 143     /*
 144      * Used to allow urgent requests to override rate limiting.
 145      */
 146     QemuSemaphore rate_limit_sem;
 147
 148     /* pages already send at the beginning of current iteration */
 149     uint64_t iteration_initial_pages;
 150
 151     /* pages transferred per second */
 152     double pages_per_second;
 153
 154     /* bytes already send at the beginning of current iteration */
 155     uint64_t iteration_initial_bytes;
 156     /* time at the start of current iteration */
 157     int64_t iteration_start_time;
 158     /*
 159      * The final stage happens when the remaining data is smaller than
 160      * this threshold; it's calculated from the requested downtime and
 161      * measured bandwidth
 162      */
 163     int64_t threshold_size;
 164
 165     /* params from 'migrate-set-parameters' */
 166     MigrationParameters parameters;
 167
 168     int state;
 169
 170     /* State related to return path */
 171     struct {
 172         QEMUFile     *from_dst_file;
 173         QemuThread    rp_thread;
 174         bool          error;
 175         QemuSemaphore rp_sem;
 176     } rp_state;
 177
 178     double mbps;
 179     /* Timestamp when recent migration starts (ms) */
 180     int64_t start_time;
 181     /* Total time used by latest migration (ms) */
 182     int64_t total_time;
 183     /* Timestamp when VM is down (ms) to migrate the last stuff */
 184     int64_t downtime_start;
 185     int64_t downtime;
 186     int64_t expected_downtime;
 187     bool enabled_capabilities[MIGRATION_CAPABILITY__MAX];
 188     int64_t setup_time;
 189     /*
 190      * Whether guest was running when we enter the completion stage.
 191      * If migration is interrupted by any reason, we need to continue
 192      * running the guest on source.
 193      */
 194     bool vm_was_running;
 195
 196     /* Flag set once the migration has been asked to enter postcopy */
 197     bool start_postcopy;
 198     /* Flag set after postcopy has sent the device state */
 199     bool postcopy_after_devices;
 200
 201     /* Flag set once the migration thread is running (and needs joining) */
 202     bool migration_thread_running;
 203
 204     /* Flag set once the migration thread called bdrv_inactivate_all */
 205     bool block_inactive;
 206
 207     /* Migration is waiting for guest to unplug device */
 208     QemuSemaphore wait_unplug_sem;
 209
 210     /* Migration is paused due to pause-before-switchover */
 211     QemuSemaphore pause_sem;
 212
 213     /* The semaphore is used to notify COLO thread that failover is finished */
 214     QemuSemaphore colo_exit_sem;
 215
 216     /* The event is used to notify COLO thread to do checkpoint */
 217     QemuEvent colo_checkpoint_event;
 218     int64_t colo_checkpoint_time;
 219     QEMUTimer *colo_delay_timer;
 220
 221     /* The first error that has occurred.
 222        We used the mutex to be able to return the 1st error message */
 223     Error *error;
 224     /* mutex to protect errp */
 225     QemuMutex error_mutex;
 226
 227     /* Do we have to clean up -b/-i from old migrate parameters */
 228     /* This feature is deprecated and will be removed */
 229     bool must_remove_block_options;
 230
 231     /*
 232      * Global switch on whether we need to store the global state
 233      * during migration.
 234      */
 235     bool store_global_state;
 236
 237     /* Whether we send QEMU_VM_CONFIGURATION during migration */
 238     bool send_configuration;
 239     /* Whether we send section footer during migration */
 240     bool send_section_footer;
 241
 242     /* Needed by postcopy-pause state */
 243     QemuSemaphore postcopy_pause_sem;
 244     QemuSemaphore postcopy_pause_rp_sem;
 245     /*
 246      * Whether we abort the migration if decompression errors are
 247      * detected at the destination. It is left at false for qemu
 248      * older than 3.0, since only newer qemu sends streams that
 249      * do not trigger spurious decompression errors.
 250      */
 251     bool decompress_error_check;
 252
 253     /*
 254      * This decides the size of guest memory chunk that will be used
 255      * to track dirty bitmap clearing.  The size of memory chunk will
 256      * be GUEST_PAGE_SIZE << N.  Say, N=0 means we will clear dirty
 257      * bitmap for each page to send (1<<0=1); N=10 means we will clear
 258      * dirty bitmap only once for 1<<10=1K continuous guest pages
 259      * (which is in 4M chunk).
 260      */
 261     uint8_t clear_bitmap_shift;
 262
 263     /*
 264      * This save hostname when out-going migration starts
 265      */
 266     char *hostname;
 267 };
 268
 269 void migrate_set_state(int *state, int old_state, int new_state);
 270
 271 void migration_fd_process_incoming(QEMUFile *f, Error **errp);
 272 void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp);
 273 void migration_incoming_process(void);
 274
 275 bool  migration_has_all_channels(void);
 276
 277 uint64_t migrate_max_downtime(void);
 278
 279 void migrate_set_error(MigrationState *s, const Error *error);
 280 void migrate_fd_error(MigrationState *s, const Error *error);
 281
 282 void migrate_fd_connect(MigrationState *s, Error *error_in);
 283
 284 bool migration_is_setup_or_active(int state);
 285 bool migration_is_running(int state);
 286
 287 void migrate_init(MigrationState *s);
 288 bool migration_is_blocked(Error **errp);
 289 /* True if outgoing migration has entered postcopy phase */
 290 bool migration_in_postcopy(void);
 291 MigrationState *migrate_get_current(void);
 292
 293 bool migrate_postcopy(void);
 294
 295 bool migrate_release_ram(void);
 296 bool migrate_postcopy_ram(void);
 297 bool migrate_zero_blocks(void);
 298 bool migrate_dirty_bitmaps(void);
 299 bool migrate_ignore_shared(void);
 300 bool migrate_validate_uuid(void);
 301
 302 bool migrate_auto_converge(void);
 303 bool migrate_use_multifd(void);
 304 bool migrate_pause_before_switchover(void);
 305 int migrate_multifd_channels(void);
 306 MultiFDCompression migrate_multifd_compression(void);
 307 int migrate_multifd_zlib_level(void);
 308 int migrate_multifd_zstd_level(void);
 309
 310 int migrate_use_xbzrle(void);
 311 int64_t migrate_xbzrle_cache_size(void);
 312 bool migrate_colo_enabled(void);
 313
 314 bool migrate_use_block(void);
 315 bool migrate_use_block_incremental(void);
 316 int migrate_max_cpu_throttle(void);
 317 bool migrate_use_return_path(void);
 318
 319 uint64_t ram_get_total_transferred_pages(void);
 320
 321 bool migrate_use_compression(void);
 322 int migrate_compress_level(void);
 323 int migrate_compress_threads(void);
 324 int migrate_compress_wait_thread(void);
 325 int migrate_decompress_threads(void);
 326 bool migrate_use_events(void);
 327 bool migrate_postcopy_blocktime(void);
 328
 329 /* Sending on the return path - generic and then for each message type */
 330 void migrate_send_rp_shut(MigrationIncomingState *mis,
 331                           uint32_t value);
 332 void migrate_send_rp_pong(MigrationIncomingState *mis,
 333                           uint32_t value);
 334 int migrate_send_rp_req_pages(MigrationIncomingState *mis, RAMBlock *rb,
 335                               ram_addr_t start);
 336 void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis,
 337                                  char *block_name);
 338 void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value);
 339
 340 void dirty_bitmap_mig_before_vm_start(void);
 341 void dirty_bitmap_mig_cancel_outgoing(void);
 342 void dirty_bitmap_mig_cancel_incoming(void);
 343 bool check_dirty_bitmap_mig_alias_map(const BitmapMigrationNodeAliasList *bbm,
 344                                       Error **errp);
 345
 346 void migrate_add_address(SocketAddress *address);
 347
 348 int foreach_not_ignored_block(RAMBlockIterFunc func, void *opaque);
 349
 350 #define qemu_ram_foreach_block \
 351   #warning "Use foreach_not_ignored_block in migration code"
 352
 353 void migration_make_urgent_request(void);
 354 void migration_consume_urgent_request(void);
 355 bool migration_rate_limit(void);
 356
 357 #endif