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 "exec/cpu-common.h"
  20 #include "qemu/coroutine_int.h"
  21 #include "hw/qdev.h"
  22 #include "io/channel.h"
  23
  24 /* State for the incoming migration */
  25 struct MigrationIncomingState {
  26     QEMUFile *from_src_file;
  27
  28     /*
  29      * Free at the start of the main state load, set as the main thread finishes
  30      * loading state.
  31      */
  32     QemuEvent main_thread_load_event;
  33
  34     size_t         largest_page_size;
  35     bool           have_fault_thread;
  36     QemuThread     fault_thread;
  37     QemuSemaphore  fault_thread_sem;
  38
  39     bool           have_listen_thread;
  40     QemuThread     listen_thread;
  41     QemuSemaphore  listen_thread_sem;
  42
  43     /* For the kernel to send us notifications */
  44     int       userfault_fd;
  45     /* To tell the fault_thread to quit */
  46     int       userfault_quit_fd;
  47     QEMUFile *to_src_file;
  48     QemuMutex rp_mutex;    /* We send replies from multiple threads */
  49     void     *postcopy_tmp_page;
  50     void     *postcopy_tmp_zero_page;
  51
  52     QEMUBH *bh;
  53
  54     int state;
  55
  56     bool have_colo_incoming_thread;
  57     QemuThread colo_incoming_thread;
  58     /* The coroutine we should enter (back) after failover */
  59     Coroutine *migration_incoming_co;
  60     QemuSemaphore colo_incoming_sem;
  61 };
  62
  63 MigrationIncomingState *migration_incoming_get_current(void);
  64 void migration_incoming_state_destroy(void);
  65
  66 #define TYPE_MIGRATION "migration"
  67
  68 #define MIGRATION_CLASS(klass) \
  69     OBJECT_CLASS_CHECK(MigrationClass, (klass), TYPE_MIGRATION)
  70 #define MIGRATION_OBJ(obj) \
  71     OBJECT_CHECK(MigrationState, (obj), TYPE_MIGRATION)
  72 #define MIGRATION_GET_CLASS(obj) \
  73     OBJECT_GET_CLASS(MigrationClass, (obj), TYPE_MIGRATION)
  74
  75 typedef struct MigrationClass {
  76     /*< private >*/
  77     DeviceClass parent_class;
  78 } MigrationClass;
  79
  80 struct MigrationState
  81 {
  82     /*< private >*/
  83     DeviceState parent_obj;
  84
  85     /*< public >*/
  86     size_t bytes_xfer;
  87     size_t xfer_limit;
  88     QemuThread thread;
  89     QEMUBH *cleanup_bh;
  90     QEMUFile *to_dst_file;
  91
  92     /* bytes already send at the beggining of current interation */
  93     uint64_t iteration_initial_bytes;
  94     /* time at the start of current iteration */
  95     int64_t iteration_start_time;
  96     /*
  97      * The final stage happens when the remaining data is smaller than
  98      * this threshold; it's calculated from the requested downtime and
  99      * measured bandwidth
 100      */
 101     int64_t threshold_size;
 102
 103     /* params from 'migrate-set-parameters' */
 104     MigrationParameters parameters;
 105
 106     int state;
 107
 108     /* State related to return path */
 109     struct {
 110         QEMUFile     *from_dst_file;
 111         QemuThread    rp_thread;
 112         bool          error;
 113     } rp_state;
 114
 115     double mbps;
 116     /* Timestamp when recent migration starts (ms) */
 117     int64_t start_time;
 118     /* Total time used by latest migration (ms) */
 119     int64_t total_time;
 120     /* Timestamp when VM is down (ms) to migrate the last stuff */
 121     int64_t downtime_start;
 122     int64_t downtime;
 123     int64_t expected_downtime;
 124     bool enabled_capabilities[MIGRATION_CAPABILITY__MAX];
 125     int64_t setup_time;
 126     /*
 127      * Whether guest was running when we enter the completion stage.
 128      * If migration is interrupted by any reason, we need to continue
 129      * running the guest on source.
 130      */
 131     bool vm_was_running;
 132
 133     /* Flag set once the migration has been asked to enter postcopy */
 134     bool start_postcopy;
 135     /* Flag set after postcopy has sent the device state */
 136     bool postcopy_after_devices;
 137
 138     /* Flag set once the migration thread is running (and needs joining) */
 139     bool migration_thread_running;
 140
 141     /* Flag set once the migration thread called bdrv_inactivate_all */
 142     bool block_inactive;
 143
 144     /* Migration is paused due to pause-before-switchover */
 145     QemuSemaphore pause_sem;
 146
 147     /* The semaphore is used to notify COLO thread that failover is finished */
 148     QemuSemaphore colo_exit_sem;
 149
 150     /* The semaphore is used to notify COLO thread to do checkpoint */
 151     QemuSemaphore colo_checkpoint_sem;
 152     int64_t colo_checkpoint_time;
 153     QEMUTimer *colo_delay_timer;
 154
 155     /* The first error that has occurred.
 156        We used the mutex to be able to return the 1st error message */
 157     Error *error;
 158     /* mutex to protect errp */
 159     QemuMutex error_mutex;
 160
 161     /* Do we have to clean up -b/-i from old migrate parameters */
 162     /* This feature is deprecated and will be removed */
 163     bool must_remove_block_options;
 164
 165     /*
 166      * Global switch on whether we need to store the global state
 167      * during migration.
 168      */
 169     bool store_global_state;
 170
 171     /* Whether the VM is only allowing for migratable devices */
 172     bool only_migratable;
 173
 174     /* Whether we send QEMU_VM_CONFIGURATION during migration */
 175     bool send_configuration;
 176     /* Whether we send section footer during migration */
 177     bool send_section_footer;
 178 };
 179
 180 void migrate_set_state(int *state, int old_state, int new_state);
 181
 182 void migration_fd_process_incoming(QEMUFile *f);
 183 void migration_ioc_process_incoming(QIOChannel *ioc);
 184
 185 bool  migration_has_all_channels(void);
 186
 187 uint64_t migrate_max_downtime(void);
 188
 189 void migrate_set_error(MigrationState *s, const Error *error);
 190 void migrate_fd_error(MigrationState *s, const Error *error);
 191
 192 void migrate_fd_connect(MigrationState *s, Error *error_in);
 193
 194 MigrationState *migrate_init(void);
 195 bool migration_is_blocked(Error **errp);
 196 /* True if outgoing migration has entered postcopy phase */
 197 bool migration_in_postcopy(void);
 198 MigrationState *migrate_get_current(void);
 199
 200 bool migrate_postcopy(void);
 201
 202 bool migrate_release_ram(void);
 203 bool migrate_postcopy_ram(void);
 204 bool migrate_zero_blocks(void);
 205
 206 bool migrate_auto_converge(void);
 207 bool migrate_use_multifd(void);
 208 bool migrate_pause_before_switchover(void);
 209 int migrate_multifd_channels(void);
 210 int migrate_multifd_page_count(void);
 211
 212 int migrate_use_xbzrle(void);
 213 int64_t migrate_xbzrle_cache_size(void);
 214 bool migrate_colo_enabled(void);
 215
 216 bool migrate_use_block(void);
 217 bool migrate_use_block_incremental(void);
 218 bool migrate_use_return_path(void);
 219
 220 bool migrate_use_compression(void);
 221 int migrate_compress_level(void);
 222 int migrate_compress_threads(void);
 223 int migrate_decompress_threads(void);
 224 bool migrate_use_events(void);
 225
 226 /* Sending on the return path - generic and then for each message type */
 227 void migrate_send_rp_shut(MigrationIncomingState *mis,
 228                           uint32_t value);
 229 void migrate_send_rp_pong(MigrationIncomingState *mis,
 230                           uint32_t value);
 231 void migrate_send_rp_req_pages(MigrationIncomingState *mis, const char* rbname,
 232                               ram_addr_t start, size_t len);
 233
 234 #endif