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     QemuSemaphore postcopy_pause_sem_dst;
  81     QemuSemaphore postcopy_pause_sem_fault;
  82 };
  83
  84 MigrationIncomingState *migration_incoming_get_current(void);
  85 void migration_incoming_state_destroy(void);
  86 /*
  87  * Functions to work with blocktime context
  88  */
  89 void fill_destination_postcopy_migration_info(MigrationInfo *info);
  90
  91 #define TYPE_MIGRATION "migration"
  92
  93 #define MIGRATION_CLASS(klass) \
  94     OBJECT_CLASS_CHECK(MigrationClass, (klass), TYPE_MIGRATION)
  95 #define MIGRATION_OBJ(obj) \
  96     OBJECT_CHECK(MigrationState, (obj), TYPE_MIGRATION)
  97 #define MIGRATION_GET_CLASS(obj) \
  98     OBJECT_GET_CLASS(MigrationClass, (obj), TYPE_MIGRATION)
  99
 100 typedef struct MigrationClass {
 101     /*< private >*/
 102     DeviceClass parent_class;
 103 } MigrationClass;
 104
 105 struct MigrationState
 106 {
 107     /*< private >*/
 108     DeviceState parent_obj;
 109
 110     /*< public >*/
 111     size_t bytes_xfer;
 112     size_t xfer_limit;
 113     QemuThread thread;
 114     QEMUBH *cleanup_bh;
 115     QEMUFile *to_dst_file;
 116
 117     /* bytes already send at the beggining of current interation */
 118     uint64_t iteration_initial_bytes;
 119     /* time at the start of current iteration */
 120     int64_t iteration_start_time;
 121     /*
 122      * The final stage happens when the remaining data is smaller than
 123      * this threshold; it's calculated from the requested downtime and
 124      * measured bandwidth
 125      */
 126     int64_t threshold_size;
 127
 128     /* params from 'migrate-set-parameters' */
 129     MigrationParameters parameters;
 130
 131     int state;
 132
 133     /* State related to return path */
 134     struct {
 135         QEMUFile     *from_dst_file;
 136         QemuThread    rp_thread;
 137         bool          error;
 138     } rp_state;
 139
 140     double mbps;
 141     /* Timestamp when recent migration starts (ms) */
 142     int64_t start_time;
 143     /* Total time used by latest migration (ms) */
 144     int64_t total_time;
 145     /* Timestamp when VM is down (ms) to migrate the last stuff */
 146     int64_t downtime_start;
 147     int64_t downtime;
 148     int64_t expected_downtime;
 149     bool enabled_capabilities[MIGRATION_CAPABILITY__MAX];
 150     int64_t setup_time;
 151     /*
 152      * Whether guest was running when we enter the completion stage.
 153      * If migration is interrupted by any reason, we need to continue
 154      * running the guest on source.
 155      */
 156     bool vm_was_running;
 157
 158     /* Flag set once the migration has been asked to enter postcopy */
 159     bool start_postcopy;
 160     /* Flag set after postcopy has sent the device state */
 161     bool postcopy_after_devices;
 162
 163     /* Flag set once the migration thread is running (and needs joining) */
 164     bool migration_thread_running;
 165
 166     /* Flag set once the migration thread called bdrv_inactivate_all */
 167     bool block_inactive;
 168
 169     /* Migration is paused due to pause-before-switchover */
 170     QemuSemaphore pause_sem;
 171
 172     /* The semaphore is used to notify COLO thread that failover is finished */
 173     QemuSemaphore colo_exit_sem;
 174
 175     /* The semaphore is used to notify COLO thread to do checkpoint */
 176     QemuSemaphore colo_checkpoint_sem;
 177     int64_t colo_checkpoint_time;
 178     QEMUTimer *colo_delay_timer;
 179
 180     /* The first error that has occurred.
 181        We used the mutex to be able to return the 1st error message */
 182     Error *error;
 183     /* mutex to protect errp */
 184     QemuMutex error_mutex;
 185
 186     /* Do we have to clean up -b/-i from old migrate parameters */
 187     /* This feature is deprecated and will be removed */
 188     bool must_remove_block_options;
 189
 190     /*
 191      * Global switch on whether we need to store the global state
 192      * during migration.
 193      */
 194     bool store_global_state;
 195
 196     /* Whether the VM is only allowing for migratable devices */
 197     bool only_migratable;
 198
 199     /* Whether we send QEMU_VM_CONFIGURATION during migration */
 200     bool send_configuration;
 201     /* Whether we send section footer during migration */
 202     bool send_section_footer;
 203
 204     /* Needed by postcopy-pause state */
 205     QemuSemaphore postcopy_pause_sem;
 206     QemuSemaphore postcopy_pause_rp_sem;
 207 };
 208
 209 void migrate_set_state(int *state, int old_state, int new_state);
 210
 211 void migration_fd_process_incoming(QEMUFile *f);
 212 void migration_ioc_process_incoming(QIOChannel *ioc);
 213 void migration_incoming_process(void);
 214
 215 bool  migration_has_all_channels(void);
 216
 217 uint64_t migrate_max_downtime(void);
 218
 219 void migrate_set_error(MigrationState *s, const Error *error);
 220 void migrate_fd_error(MigrationState *s, const Error *error);
 221
 222 void migrate_fd_connect(MigrationState *s, Error *error_in);
 223
 224 void migrate_init(MigrationState *s);
 225 bool migration_is_blocked(Error **errp);
 226 /* True if outgoing migration has entered postcopy phase */
 227 bool migration_in_postcopy(void);
 228 MigrationState *migrate_get_current(void);
 229
 230 bool migrate_postcopy(void);
 231
 232 bool migrate_release_ram(void);
 233 bool migrate_postcopy_ram(void);
 234 bool migrate_zero_blocks(void);
 235 bool migrate_dirty_bitmaps(void);
 236
 237 bool migrate_auto_converge(void);
 238 bool migrate_use_multifd(void);
 239 bool migrate_pause_before_switchover(void);
 240 int migrate_multifd_channels(void);
 241 int migrate_multifd_page_count(void);
 242
 243 int migrate_use_xbzrle(void);
 244 int64_t migrate_xbzrle_cache_size(void);
 245 bool migrate_colo_enabled(void);
 246
 247 bool migrate_use_block(void);
 248 bool migrate_use_block_incremental(void);
 249 bool migrate_use_return_path(void);
 250
 251 bool migrate_use_compression(void);
 252 int migrate_compress_level(void);
 253 int migrate_compress_threads(void);
 254 int migrate_decompress_threads(void);
 255 bool migrate_use_events(void);
 256 bool migrate_postcopy_blocktime(void);
 257
 258 /* Sending on the return path - generic and then for each message type */
 259 void migrate_send_rp_shut(MigrationIncomingState *mis,
 260                           uint32_t value);
 261 void migrate_send_rp_pong(MigrationIncomingState *mis,
 262                           uint32_t value);
 263 int migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname,
 264                               ram_addr_t start, size_t len);
 265 void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis,
 266                                  char *block_name);
 267 void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value);
 268
 269 void dirty_bitmap_mig_before_vm_start(void);
 270 void init_dirty_bitmap_incoming_migration(void);
 271
 272 #endif