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 /* 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