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 "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 struct PostcopyBlocktimeContext;
  26
  27 /* State for the incoming migration */
  28 struct MigrationIncomingState {
  29     QEMUFile *from_src_file;
  30
  31     /*
  32      * Free at the start of the main state load, set as the main thread finishes
  33      * loading state.
  34      */
  35     QemuEvent main_thread_load_event;
  36
  37     size_t         largest_page_size;
  38     bool           have_fault_thread;
  39     QemuThread     fault_thread;
  40     QemuSemaphore  fault_thread_sem;
  41
  42     bool           have_listen_thread;
  43     QemuThread     listen_thread;
  44     QemuSemaphore  listen_thread_sem;
  45
  46     /* For the kernel to send us notifications */
  47     int       userfault_fd;
  48     /* To tell the fault_thread to quit */
  49     int       userfault_quit_fd;
  50     QEMUFile *to_src_file;
  51     QemuMutex rp_mutex;    /* We send replies from multiple threads */
  52     void     *postcopy_tmp_page;
  53     void     *postcopy_tmp_zero_page;
  54
  55     QEMUBH *bh;
  56
  57     int state;
  58
  59     bool have_colo_incoming_thread;
  60     QemuThread colo_incoming_thread;
  61     /* The coroutine we should enter (back) after failover */
  62     Coroutine *migration_incoming_co;
  63     QemuSemaphore colo_incoming_sem;
  64
  65     /*
  66      * PostcopyBlocktimeContext to keep information for postcopy
  67      * live migration, to calculate vCPU block time
  68      * */
  69     struct PostcopyBlocktimeContext *blocktime_ctx;
  70 };
  71
  72 MigrationIncomingState *migration_incoming_get_current(void);
  73 void migration_incoming_state_destroy(void);
  74 /*
  75  * Functions to work with blocktime context
  76  */
  77 void fill_destination_postcopy_migration_info(MigrationInfo *info);
  78
  79 #define TYPE_MIGRATION "migration"
  80
  81 #define MIGRATION_CLASS(klass) \
  82     OBJECT_CLASS_CHECK(MigrationClass, (klass), TYPE_MIGRATION)
  83 #define MIGRATION_OBJ(obj) \
  84     OBJECT_CHECK(MigrationState, (obj), TYPE_MIGRATION)
  85 #define MIGRATION_GET_CLASS(obj) \
  86     OBJECT_GET_CLASS(MigrationClass, (obj), TYPE_MIGRATION)
  87
  88 typedef struct MigrationClass {
  89     /*< private >*/
  90     DeviceClass parent_class;
  91 } MigrationClass;
  92
  93 struct MigrationState
  94 {
  95     /*< private >*/
  96     DeviceState parent_obj;
  97
  98     /*< public >*/
  99     size_t bytes_xfer;
 100     size_t xfer_limit;
 101     QemuThread thread;
 102     QEMUBH *cleanup_bh;
 103     QEMUFile *to_dst_file;
 104
 105     /* bytes already send at the beggining of current interation */
 106     uint64_t iteration_initial_bytes;
 107     /* time at the start of current iteration */
 108     int64_t iteration_start_time;
 109     /*
 110      * The final stage happens when the remaining data is smaller than
 111      * this threshold; it's calculated from the requested downtime and
 112      * measured bandwidth
 113      */
 114     int64_t threshold_size;
 115
 116     /* params from 'migrate-set-parameters' */
 117     MigrationParameters parameters;
 118
 119     int state;
 120
 121     /* State related to return path */
 122     struct {
 123         QEMUFile     *from_dst_file;
 124         QemuThread    rp_thread;
 125         bool          error;
 126     } rp_state;
 127
 128     double mbps;
 129     /* Timestamp when recent migration starts (ms) */
 130     int64_t start_time;
 131     /* Total time used by latest migration (ms) */
 132     int64_t total_time;
 133     /* Timestamp when VM is down (ms) to migrate the last stuff */
 134     int64_t downtime_start;
 135     int64_t downtime;
 136     int64_t expected_downtime;
 137     bool enabled_capabilities[MIGRATION_CAPABILITY__MAX];
 138     int64_t setup_time;
 139     /*
 140      * Whether guest was running when we enter the completion stage.
 141      * If migration is interrupted by any reason, we need to continue
 142      * running the guest on source.
 143      */
 144     bool vm_was_running;
 145
 146     /* Flag set once the migration has been asked to enter postcopy */
 147     bool start_postcopy;
 148     /* Flag set after postcopy has sent the device state */
 149     bool postcopy_after_devices;
 150
 151     /* Flag set once the migration thread is running (and needs joining) */
 152     bool migration_thread_running;
 153
 154     /* Flag set once the migration thread called bdrv_inactivate_all */
 155     bool block_inactive;
 156
 157     /* Migration is paused due to pause-before-switchover */
 158     QemuSemaphore pause_sem;
 159
 160     /* The semaphore is used to notify COLO thread that failover is finished */
 161     QemuSemaphore colo_exit_sem;
 162
 163     /* The semaphore is used to notify COLO thread to do checkpoint */
 164     QemuSemaphore colo_checkpoint_sem;
 165     int64_t colo_checkpoint_time;
 166     QEMUTimer *colo_delay_timer;
 167
 168     /* The first error that has occurred.
 169        We used the mutex to be able to return the 1st error message */
 170     Error *error;
 171     /* mutex to protect errp */
 172     QemuMutex error_mutex;
 173
 174     /* Do we have to clean up -b/-i from old migrate parameters */
 175     /* This feature is deprecated and will be removed */
 176     bool must_remove_block_options;
 177
 178     /*
 179      * Global switch on whether we need to store the global state
 180      * during migration.
 181      */
 182     bool store_global_state;
 183
 184     /* Whether the VM is only allowing for migratable devices */
 185     bool only_migratable;
 186
 187     /* Whether we send QEMU_VM_CONFIGURATION during migration */
 188     bool send_configuration;
 189     /* Whether we send section footer during migration */
 190     bool send_section_footer;
 191 };
 192
 193 void migrate_set_state(int *state, int old_state, int new_state);
 194
 195 void migration_fd_process_incoming(QEMUFile *f);
 196 void migration_ioc_process_incoming(QIOChannel *ioc);
 197
 198 bool  migration_has_all_channels(void);
 199
 200 uint64_t migrate_max_downtime(void);
 201
 202 void migrate_set_error(MigrationState *s, const Error *error);
 203 void migrate_fd_error(MigrationState *s, const Error *error);
 204
 205 void migrate_fd_connect(MigrationState *s);
 206
 207 MigrationState *migrate_init(void);
 208 bool migration_is_blocked(Error **errp);
 209 /* True if outgoing migration has entered postcopy phase */
 210 bool migration_in_postcopy(void);
 211 MigrationState *migrate_get_current(void);
 212
 213 bool migrate_postcopy(void);
 214
 215 bool migrate_release_ram(void);
 216 bool migrate_postcopy_ram(void);
 217 bool migrate_zero_blocks(void);
 218
 219 bool migrate_auto_converge(void);
 220 bool migrate_use_multifd(void);
 221 bool migrate_pause_before_switchover(void);
 222 int migrate_multifd_channels(void);
 223 int migrate_multifd_page_count(void);
 224
 225 int migrate_use_xbzrle(void);
 226 int64_t migrate_xbzrle_cache_size(void);
 227 bool migrate_colo_enabled(void);
 228
 229 bool migrate_use_block(void);
 230 bool migrate_use_block_incremental(void);
 231 bool migrate_use_return_path(void);
 232
 233 bool migrate_use_compression(void);
 234 int migrate_compress_level(void);
 235 int migrate_compress_threads(void);
 236 int migrate_decompress_threads(void);
 237 bool migrate_use_events(void);
 238 bool migrate_postcopy_blocktime(void);
 239
 240 /* Sending on the return path - generic and then for each message type */
 241 void migrate_send_rp_shut(MigrationIncomingState *mis,
 242                           uint32_t value);
 243 void migrate_send_rp_pong(MigrationIncomingState *mis,
 244                           uint32_t value);
 245 void migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname,
 246                               ram_addr_t start, size_t len);
 247
 248 #endif