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 "qemu/thread.h" 19 #include "qapi-types.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 /* State for the incoming migration */ 26 struct MigrationIncomingState { 27 QEMUFile *from_src_file; 28 29 /* 30 * Free at the start of the main state load, set as the main thread finishes 31 * loading state. 32 */ 33 QemuEvent main_thread_load_event; 34 35 size_t largest_page_size; 36 bool have_fault_thread; 37 QemuThread fault_thread; 38 QemuSemaphore fault_thread_sem; 39 40 bool have_listen_thread; 41 QemuThread listen_thread; 42 QemuSemaphore listen_thread_sem; 43 44 /* For the kernel to send us notifications */ 45 int userfault_fd; 46 /* To tell the fault_thread to quit */ 47 int userfault_quit_fd; 48 QEMUFile *to_src_file; 49 QemuMutex rp_mutex; /* We send replies from multiple threads */ 50 void *postcopy_tmp_page; 51 void *postcopy_tmp_zero_page; 52 53 QEMUBH *bh; 54 55 int state; 56 57 bool have_colo_incoming_thread; 58 QemuThread colo_incoming_thread; 59 /* The coroutine we should enter (back) after failover */ 60 Coroutine *migration_incoming_co; 61 QemuSemaphore colo_incoming_sem; 62 }; 63 64 MigrationIncomingState *migration_incoming_get_current(void); 65 void migration_incoming_state_destroy(void); 66 67 #define TYPE_MIGRATION "migration" 68 69 #define MIGRATION_CLASS(klass) \ 70 OBJECT_CLASS_CHECK(MigrationClass, (klass), TYPE_MIGRATION) 71 #define MIGRATION_OBJ(obj) \ 72 OBJECT_CHECK(MigrationState, (obj), TYPE_MIGRATION) 73 #define MIGRATION_GET_CLASS(obj) \ 74 OBJECT_GET_CLASS(MigrationClass, (obj), TYPE_MIGRATION) 75 76 typedef struct MigrationClass { 77 /*< private >*/ 78 DeviceClass parent_class; 79 } MigrationClass; 80 81 struct MigrationState 82 { 83 /*< private >*/ 84 DeviceState parent_obj; 85 86 /*< public >*/ 87 size_t bytes_xfer; 88 size_t xfer_limit; 89 QemuThread thread; 90 QEMUBH *cleanup_bh; 91 QEMUFile *to_dst_file; 92 93 /* bytes already send at the beggining of current interation */ 94 uint64_t iteration_initial_bytes; 95 /* time at the start of current iteration */ 96 int64_t iteration_start_time; 97 /* 98 * The final stage happens when the remaining data is smaller than 99 * this threshold; it's calculated from the requested downtime and 100 * measured bandwidth 101 */ 102 int64_t threshold_size; 103 104 /* params from 'migrate-set-parameters' */ 105 MigrationParameters parameters; 106 107 int state; 108 109 /* State related to return path */ 110 struct { 111 QEMUFile *from_dst_file; 112 QemuThread rp_thread; 113 bool error; 114 } rp_state; 115 116 double mbps; 117 /* Timestamp when recent migration starts (ms) */ 118 int64_t start_time; 119 /* Total time used by latest migration (ms) */ 120 int64_t total_time; 121 /* Timestamp when VM is down (ms) to migrate the last stuff */ 122 int64_t downtime_start; 123 int64_t downtime; 124 int64_t expected_downtime; 125 bool enabled_capabilities[MIGRATION_CAPABILITY__MAX]; 126 int64_t setup_time; 127 /* 128 * Whether guest was running when we enter the completion stage. 129 * If migration is interrupted by any reason, we need to continue 130 * running the guest on source. 131 */ 132 bool vm_was_running; 133 134 /* Flag set once the migration has been asked to enter postcopy */ 135 bool start_postcopy; 136 /* Flag set after postcopy has sent the device state */ 137 bool postcopy_after_devices; 138 139 /* Flag set once the migration thread is running (and needs joining) */ 140 bool migration_thread_running; 141 142 /* Flag set once the migration thread called bdrv_inactivate_all */ 143 bool block_inactive; 144 145 /* Migration is paused due to pause-before-switchover */ 146 QemuSemaphore pause_sem; 147 148 /* The semaphore is used to notify COLO thread that failover is finished */ 149 QemuSemaphore colo_exit_sem; 150 151 /* The semaphore is used to notify COLO thread to do checkpoint */ 152 QemuSemaphore colo_checkpoint_sem; 153 int64_t colo_checkpoint_time; 154 QEMUTimer *colo_delay_timer; 155 156 /* The first error that has occurred. 157 We used the mutex to be able to return the 1st error message */ 158 Error *error; 159 /* mutex to protect errp */ 160 QemuMutex error_mutex; 161 162 /* Do we have to clean up -b/-i from old migrate parameters */ 163 /* This feature is deprecated and will be removed */ 164 bool must_remove_block_options; 165 166 /* 167 * Global switch on whether we need to store the global state 168 * during migration. 169 */ 170 bool store_global_state; 171 172 /* Whether the VM is only allowing for migratable devices */ 173 bool only_migratable; 174 175 /* Whether we send QEMU_VM_CONFIGURATION during migration */ 176 bool send_configuration; 177 /* Whether we send section footer during migration */ 178 bool send_section_footer; 179 }; 180 181 void migrate_set_state(int *state, int old_state, int new_state); 182 183 void migration_fd_process_incoming(QEMUFile *f); 184 void migration_ioc_process_incoming(QIOChannel *ioc); 185 186 bool migration_has_all_channels(void); 187 188 uint64_t migrate_max_downtime(void); 189 190 void migrate_set_error(MigrationState *s, const Error *error); 191 void migrate_fd_error(MigrationState *s, const Error *error); 192 193 void migrate_fd_connect(MigrationState *s); 194 195 MigrationState *migrate_init(void); 196 bool migration_is_blocked(Error **errp); 197 /* True if outgoing migration has entered postcopy phase */ 198 bool migration_in_postcopy(void); 199 MigrationState *migrate_get_current(void); 200 201 bool migrate_postcopy(void); 202 203 bool migrate_release_ram(void); 204 bool migrate_postcopy_ram(void); 205 bool migrate_zero_blocks(void); 206 207 bool migrate_auto_converge(void); 208 bool migrate_use_multifd(void); 209 bool migrate_pause_before_switchover(void); 210 int migrate_multifd_channels(void); 211 int migrate_multifd_page_count(void); 212 213 int migrate_use_xbzrle(void); 214 int64_t migrate_xbzrle_cache_size(void); 215 bool migrate_colo_enabled(void); 216 217 bool migrate_use_block(void); 218 bool migrate_use_block_incremental(void); 219 bool migrate_use_return_path(void); 220 221 bool migrate_use_compression(void); 222 int migrate_compress_level(void); 223 int migrate_compress_threads(void); 224 int migrate_decompress_threads(void); 225 bool migrate_use_events(void); 226 227 /* Sending on the return path - generic and then for each message type */ 228 void migrate_send_rp_shut(MigrationIncomingState *mis, 229 uint32_t value); 230 void migrate_send_rp_pong(MigrationIncomingState *mis, 231 uint32_t value); 232 void migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname, 233 ram_addr_t start, size_t len); 234 235 #endif 236