diff options
| -rw-r--r-- | migration/migration.c | 99 | ||||
| -rw-r--r-- | migration/migration.h | 3 | ||||
| -rw-r--r-- | migration/trace-events | 1 |
3 files changed, 97 insertions, 6 deletions
diff --git a/migration/migration.c b/migration/migration.c index 02ebd6c9d1..8392cf467d 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -2245,6 +2245,80 @@ bool migrate_colo_enabled(void) return s->enabled_capabilities[MIGRATION_CAPABILITY_X_COLO]; } +typedef enum MigThrError { + /* No error detected */ + MIG_THR_ERR_NONE = 0, + /* Detected error, but resumed successfully */ + MIG_THR_ERR_RECOVERED = 1, + /* Detected fatal error, need to exit */ + MIG_THR_ERR_FATAL = 2, +} MigThrError; + +/* + * We don't return until we are in a safe state to continue current + * postcopy migration. Returns MIG_THR_ERR_RECOVERED if recovered, or + * MIG_THR_ERR_FATAL if unrecovery failure happened. + */ +static MigThrError postcopy_pause(MigrationState *s) +{ + assert(s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE); + migrate_set_state(&s->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, + MIGRATION_STATUS_POSTCOPY_PAUSED); + + /* Current channel is possibly broken. Release it. */ + assert(s->to_dst_file); + qemu_file_shutdown(s->to_dst_file); + qemu_fclose(s->to_dst_file); + s->to_dst_file = NULL; + + error_report("Detected IO failure for postcopy. " + "Migration paused."); + + /* + * We wait until things fixed up. Then someone will setup the + * status back for us. + */ + while (s->state == MIGRATION_STATUS_POSTCOPY_PAUSED) { + qemu_sem_wait(&s->postcopy_pause_sem); + } + + trace_postcopy_pause_continued(); + + return MIG_THR_ERR_RECOVERED; +} + +static MigThrError migration_detect_error(MigrationState *s) +{ + int ret; + + /* Try to detect any file errors */ + ret = qemu_file_get_error(s->to_dst_file); + + if (!ret) { + /* Everything is fine */ + return MIG_THR_ERR_NONE; + } + + if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE && ret == -EIO) { + /* + * For postcopy, we allow the network to be down for a + * while. After that, it can be continued by a + * recovery phase. + */ + return postcopy_pause(s); + } else { + /* + * For precopy (or postcopy with error outside IO), we fail + * with no time. + */ + migrate_set_state(&s->state, s->state, MIGRATION_STATUS_FAILED); + trace_migration_thread_file_err(); + + /* Time to stop the migration, now. */ + return MIG_THR_ERR_FATAL; + } +} + static void migration_calculate_complete(MigrationState *s) { uint64_t bytes = qemu_ftell(s->to_dst_file); @@ -2401,6 +2475,7 @@ static void *migration_thread(void *opaque) { MigrationState *s = opaque; int64_t setup_start = qemu_clock_get_ms(QEMU_CLOCK_HOST); + MigThrError thr_error; rcu_register_thread(); @@ -2450,13 +2525,22 @@ static void *migration_thread(void *opaque) } } - if (qemu_file_get_error(s->to_dst_file)) { - if (migration_is_setup_or_active(s->state)) { - migrate_set_state(&s->state, s->state, - MIGRATION_STATUS_FAILED); - } - trace_migration_thread_file_err(); + /* + * Try to detect any kind of failures, and see whether we + * should stop the migration now. + */ + thr_error = migration_detect_error(s); + if (thr_error == MIG_THR_ERR_FATAL) { + /* Stop migration */ break; + } else if (thr_error == MIG_THR_ERR_RECOVERED) { + /* + * Just recovered from a e.g. network failure, reset all + * the local variables. This is important to avoid + * breaking transferred_bytes and bandwidth calculation + */ + s->iteration_start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); + s->iteration_initial_bytes = 0; } current_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); @@ -2614,6 +2698,7 @@ static void migration_instance_finalize(Object *obj) g_free(params->tls_hostname); g_free(params->tls_creds); qemu_sem_destroy(&ms->pause_sem); + qemu_sem_destroy(&ms->postcopy_pause_sem); error_free(ms->error); } @@ -2643,6 +2728,8 @@ static void migration_instance_init(Object *obj) params->has_x_multifd_channels = true; params->has_x_multifd_page_count = true; params->has_xbzrle_cache_size = true; + + qemu_sem_init(&ms->postcopy_pause_sem, 0); } /* diff --git a/migration/migration.h b/migration/migration.h index 26e5951d56..60283c39b2 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -194,6 +194,9 @@ struct MigrationState bool send_configuration; /* Whether we send section footer during migration */ bool send_section_footer; + + /* Needed by postcopy-pause state */ + QemuSemaphore postcopy_pause_sem; }; void migrate_set_state(int *state, int old_state, int new_state); diff --git a/migration/trace-events b/migration/trace-events index d6be74b7a7..409b4b8be3 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -99,6 +99,7 @@ migration_thread_setup_complete(void) "" open_return_path_on_source(void) "" open_return_path_on_source_continue(void) "" postcopy_start(void) "" +postcopy_pause_continued(void) "" postcopy_start_set_run(void) "" source_return_path_thread_bad_end(void) "" source_return_path_thread_end(void) "" |