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 /* 125 * Used to allow urgent requests to override rate limiting. 126 */ 127 QemuSemaphore rate_limit_sem; 128 129 /* bytes already send at the beggining of current interation */ 130 uint64_t iteration_initial_bytes; 131 /* time at the start of current iteration */ 132 int64_t iteration_start_time; 133 /* 134 * The final stage happens when the remaining data is smaller than 135 * this threshold; it's calculated from the requested downtime and 136 * measured bandwidth 137 */ 138 int64_t threshold_size; 139 140 /* params from 'migrate-set-parameters' */ 141 MigrationParameters parameters; 142 143 int state; 144 145 /* State related to return path */ 146 struct { 147 QEMUFile *from_dst_file; 148 QemuThread rp_thread; 149 bool error; 150 QemuSemaphore rp_sem; 151 } rp_state; 152 153 double mbps; 154 /* Timestamp when recent migration starts (ms) */ 155 int64_t start_time; 156 /* Total time used by latest migration (ms) */ 157 int64_t total_time; 158 /* Timestamp when VM is down (ms) to migrate the last stuff */ 159 int64_t downtime_start; 160 int64_t downtime; 161 int64_t expected_downtime; 162 bool enabled_capabilities[MIGRATION_CAPABILITY__MAX]; 163 int64_t setup_time; 164 /* 165 * Whether guest was running when we enter the completion stage. 166 * If migration is interrupted by any reason, we need to continue 167 * running the guest on source. 168 */ 169 bool vm_was_running; 170 171 /* Flag set once the migration has been asked to enter postcopy */ 172 bool start_postcopy; 173 /* Flag set after postcopy has sent the device state */ 174 bool postcopy_after_devices; 175 176 /* Flag set once the migration thread is running (and needs joining) */ 177 bool migration_thread_running; 178 179 /* Flag set once the migration thread called bdrv_inactivate_all */ 180 bool block_inactive; 181 182 /* Migration is paused due to pause-before-switchover */ 183 QemuSemaphore pause_sem; 184 185 /* The semaphore is used to notify COLO thread that failover is finished */ 186 QemuSemaphore colo_exit_sem; 187 188 /* The semaphore is used to notify COLO thread to do checkpoint */ 189 QemuSemaphore colo_checkpoint_sem; 190 int64_t colo_checkpoint_time; 191 QEMUTimer *colo_delay_timer; 192 193 /* The first error that has occurred. 194 We used the mutex to be able to return the 1st error message */ 195 Error *error; 196 /* mutex to protect errp */ 197 QemuMutex error_mutex; 198 199 /* Do we have to clean up -b/-i from old migrate parameters */ 200 /* This feature is deprecated and will be removed */ 201 bool must_remove_block_options; 202 203 /* 204 * Global switch on whether we need to store the global state 205 * during migration. 206 */ 207 bool store_global_state; 208 209 /* Whether the VM is only allowing for migratable devices */ 210 bool only_migratable; 211 212 /* Whether we send QEMU_VM_CONFIGURATION during migration */ 213 bool send_configuration; 214 /* Whether we send section footer during migration */ 215 bool send_section_footer; 216 217 /* Needed by postcopy-pause state */ 218 QemuSemaphore postcopy_pause_sem; 219 QemuSemaphore postcopy_pause_rp_sem; 220 /* 221 * Whether we abort the migration if decompression errors are 222 * detected at the destination. It is left at false for qemu 223 * older than 3.0, since only newer qemu sends streams that 224 * do not trigger spurious decompression errors. 225 */ 226 bool decompress_error_check; 227 }; 228 229 void migrate_set_state(int *state, int old_state, int new_state); 230 231 void migration_fd_process_incoming(QEMUFile *f); 232 void migration_ioc_process_incoming(QIOChannel *ioc); 233 void migration_incoming_process(void); 234 235 bool migration_has_all_channels(void); 236 237 uint64_t migrate_max_downtime(void); 238 239 void migrate_set_error(MigrationState *s, const Error *error); 240 void migrate_fd_error(MigrationState *s, const Error *error); 241 242 void migrate_fd_connect(MigrationState *s, Error *error_in); 243 244 void migrate_init(MigrationState *s); 245 bool migration_is_blocked(Error **errp); 246 /* True if outgoing migration has entered postcopy phase */ 247 bool migration_in_postcopy(void); 248 MigrationState *migrate_get_current(void); 249 250 bool migrate_postcopy(void); 251 252 bool migrate_release_ram(void); 253 bool migrate_postcopy_ram(void); 254 bool migrate_zero_blocks(void); 255 bool migrate_dirty_bitmaps(void); 256 257 bool migrate_auto_converge(void); 258 bool migrate_use_multifd(void); 259 bool migrate_pause_before_switchover(void); 260 int migrate_multifd_channels(void); 261 int migrate_multifd_page_count(void); 262 263 int migrate_use_xbzrle(void); 264 int64_t migrate_xbzrle_cache_size(void); 265 bool migrate_colo_enabled(void); 266 267 bool migrate_use_block(void); 268 bool migrate_use_block_incremental(void); 269 int migrate_max_cpu_throttle(void); 270 bool migrate_use_return_path(void); 271 272 bool migrate_use_compression(void); 273 int migrate_compress_level(void); 274 int migrate_compress_threads(void); 275 int migrate_compress_wait_thread(void); 276 int migrate_decompress_threads(void); 277 bool migrate_use_events(void); 278 bool migrate_postcopy_blocktime(void); 279 280 /* Sending on the return path - generic and then for each message type */ 281 void migrate_send_rp_shut(MigrationIncomingState *mis, 282 uint32_t value); 283 void migrate_send_rp_pong(MigrationIncomingState *mis, 284 uint32_t value); 285 int migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname, 286 ram_addr_t start, size_t len); 287 void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis, 288 char *block_name); 289 void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value); 290 291 void dirty_bitmap_mig_before_vm_start(void); 292 void init_dirty_bitmap_incoming_migration(void); 293 294 #define qemu_ram_foreach_block \ 295 #warning "Use qemu_ram_foreach_block_migratable in migration code" 296 297 void migration_make_urgent_request(void); 298 void migration_consume_urgent_request(void); 299 300 #endif 301