diff options
Diffstat (limited to 'migration/savevm.c')
| -rw-r--r-- | migration/savevm.c | 201 |
1 files changed, 198 insertions, 3 deletions
diff --git a/migration/savevm.c b/migration/savevm.c index 4046faf009..5c4fdfd95e 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -37,6 +37,7 @@ #include "migration/register.h" #include "migration/global_state.h" #include "migration/channel-block.h" +#include "multifd.h" #include "ram.h" #include "qemu-file.h" #include "savevm.h" @@ -54,6 +55,7 @@ #include "qemu/job.h" #include "qemu/main-loop.h" #include "block/snapshot.h" +#include "block/thread-pool.h" #include "qemu/cutils.h" #include "io/channel-buffer.h" #include "io/channel-file.h" @@ -90,6 +92,7 @@ enum qemu_vm_cmd { MIG_CMD_ENABLE_COLO, /* Enable COLO */ MIG_CMD_POSTCOPY_RESUME, /* resume postcopy on dest */ MIG_CMD_RECV_BITMAP, /* Request for recved bitmap on dst */ + MIG_CMD_SWITCHOVER_START, /* Switchover start notification */ MIG_CMD_MAX }; @@ -109,6 +112,7 @@ static struct mig_cmd_args { [MIG_CMD_POSTCOPY_RESUME] = { .len = 0, .name = "POSTCOPY_RESUME" }, [MIG_CMD_PACKAGED] = { .len = 4, .name = "PACKAGED" }, [MIG_CMD_RECV_BITMAP] = { .len = -1, .name = "RECV_BITMAP" }, + [MIG_CMD_SWITCHOVER_START] = { .len = 0, .name = "SWITCHOVER_START" }, [MIG_CMD_MAX] = { .len = -1, .name = "MAX" }, }; @@ -130,6 +134,35 @@ static struct mig_cmd_args { */ /***********************************************************/ +/* Optional load threads pool support */ + +static void qemu_loadvm_thread_pool_create(MigrationIncomingState *mis) +{ + assert(!mis->load_threads); + mis->load_threads = thread_pool_new(); + mis->load_threads_abort = false; +} + +static void qemu_loadvm_thread_pool_destroy(MigrationIncomingState *mis) +{ + qatomic_set(&mis->load_threads_abort, true); + + bql_unlock(); /* Load threads might be waiting for BQL */ + g_clear_pointer(&mis->load_threads, thread_pool_free); + bql_lock(); +} + +static bool qemu_loadvm_thread_pool_wait(MigrationState *s, + MigrationIncomingState *mis) +{ + bql_unlock(); /* Let load threads do work requiring BQL */ + thread_pool_wait(mis->load_threads); + bql_lock(); + + return !migrate_has_error(s); +} + +/***********************************************************/ /* savevm/loadvm support */ static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable) @@ -1201,6 +1234,19 @@ void qemu_savevm_send_recv_bitmap(QEMUFile *f, char *block_name) qemu_savevm_command_send(f, MIG_CMD_RECV_BITMAP, len + 1, (uint8_t *)buf); } +static void qemu_savevm_send_switchover_start(QEMUFile *f) +{ + trace_savevm_send_switchover_start(); + qemu_savevm_command_send(f, MIG_CMD_SWITCHOVER_START, 0, NULL); +} + +void qemu_savevm_maybe_send_switchover_start(QEMUFile *f) +{ + if (migrate_send_switchover_start()) { + qemu_savevm_send_switchover_start(f); + } +} + bool qemu_savevm_state_blocked(Error **errp) { SaveStateEntry *se; @@ -1482,6 +1528,24 @@ int qemu_savevm_state_complete_precopy_iterable(QEMUFile *f, bool in_postcopy) int64_t start_ts_each, end_ts_each; SaveStateEntry *se; int ret; + bool multifd_device_state = multifd_device_state_supported(); + + if (multifd_device_state) { + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + SaveLiveCompletePrecopyThreadHandler hdlr; + + if (!se->ops || (in_postcopy && se->ops->has_postcopy && + se->ops->has_postcopy(se->opaque)) || + !se->ops->save_live_complete_precopy_thread) { + continue; + } + + hdlr = se->ops->save_live_complete_precopy_thread; + multifd_spawn_device_state_save_thread(hdlr, + se->idstr, se->instance_id, + se->opaque); + } + } QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { if (!se->ops || @@ -1507,16 +1571,35 @@ int qemu_savevm_state_complete_precopy_iterable(QEMUFile *f, bool in_postcopy) save_section_footer(f, se); if (ret < 0) { qemu_file_set_error(f, ret); - return -1; + goto ret_fail_abort_threads; } end_ts_each = qemu_clock_get_us(QEMU_CLOCK_REALTIME); trace_vmstate_downtime_save("iterable", se->idstr, se->instance_id, end_ts_each - start_ts_each); } + if (multifd_device_state) { + if (migrate_has_error(migrate_get_current())) { + multifd_abort_device_state_save_threads(); + } + + if (!multifd_join_device_state_save_threads()) { + qemu_file_set_error(f, -EINVAL); + return -1; + } + } + trace_vmstate_downtime_checkpoint("src-iterable-saved"); return 0; + +ret_fail_abort_threads: + if (multifd_device_state) { + multifd_abort_device_state_save_threads(); + multifd_join_device_state_save_threads(); + } + + return -1; } int qemu_savevm_state_complete_precopy_non_iterable(QEMUFile *f, @@ -1687,6 +1770,7 @@ static int qemu_savevm_state(QEMUFile *f, Error **errp) ret = qemu_file_get_error(f); if (ret == 0) { + qemu_savevm_maybe_send_switchover_start(f); qemu_savevm_state_complete_precopy(f, false); ret = qemu_file_get_error(f); } @@ -1970,6 +2054,8 @@ static void *postcopy_ram_listen_thread(void *opaque) * in qemu_file, and thus we must be blocking now. */ qemu_file_set_blocking(f, true); + + /* TODO: sanity check that only postcopiable data will be loaded here */ load_res = qemu_loadvm_state_main(f, mis); /* @@ -2030,7 +2116,9 @@ static void *postcopy_ram_listen_thread(void *opaque) * (If something broke then qemu will have to exit anyway since it's * got a bad migration state). */ + bql_lock(); migration_incoming_state_destroy(); + bql_unlock(); rcu_unregister_thread(); mis->have_listen_thread = false; @@ -2383,6 +2471,26 @@ static int loadvm_process_enable_colo(MigrationIncomingState *mis) return ret; } +static int loadvm_postcopy_handle_switchover_start(void) +{ + SaveStateEntry *se; + + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + int ret; + + if (!se->ops || !se->ops->switchover_start) { + continue; + } + + ret = se->ops->switchover_start(se->opaque); + if (ret < 0) { + return ret; + } + } + + return 0; +} + /* * Process an incoming 'QEMU_VM_COMMAND' * 0 just a normal return @@ -2481,6 +2589,9 @@ static int loadvm_process_command(QEMUFile *f) case MIG_CMD_ENABLE_COLO: return loadvm_process_enable_colo(mis); + + case MIG_CMD_SWITCHOVER_START: + return loadvm_postcopy_handle_switchover_start(); } return 0; @@ -2740,16 +2851,68 @@ static int qemu_loadvm_state_setup(QEMUFile *f, Error **errp) return 0; } -void qemu_loadvm_state_cleanup(void) +struct LoadThreadData { + MigrationLoadThread function; + void *opaque; +}; + +static int qemu_loadvm_load_thread(void *thread_opaque) +{ + struct LoadThreadData *data = thread_opaque; + MigrationIncomingState *mis = migration_incoming_get_current(); + g_autoptr(Error) local_err = NULL; + + if (!data->function(data->opaque, &mis->load_threads_abort, &local_err)) { + MigrationState *s = migrate_get_current(); + + /* + * Can't set load_threads_abort here since processing of main migration + * channel data could still be happening, resulting in launching of new + * load threads. + */ + + assert(local_err); + + /* + * In case of multiple load threads failing which thread error + * return we end setting is purely arbitrary. + */ + migrate_set_error(s, local_err); + } + + return 0; +} + +void qemu_loadvm_start_load_thread(MigrationLoadThread function, + void *opaque) +{ + MigrationIncomingState *mis = migration_incoming_get_current(); + struct LoadThreadData *data; + + /* We only set it from this thread so it's okay to read it directly */ + assert(!mis->load_threads_abort); + + data = g_new(struct LoadThreadData, 1); + data->function = function; + data->opaque = opaque; + + thread_pool_submit_immediate(mis->load_threads, qemu_loadvm_load_thread, + data, g_free); +} + +void qemu_loadvm_state_cleanup(MigrationIncomingState *mis) { SaveStateEntry *se; trace_loadvm_state_cleanup(); + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { if (se->ops && se->ops->load_cleanup) { se->ops->load_cleanup(se->opaque); } } + + qemu_loadvm_thread_pool_destroy(mis); } /* Return true if we should continue the migration, or false. */ @@ -2900,6 +3063,7 @@ out: int qemu_loadvm_state(QEMUFile *f) { + MigrationState *s = migrate_get_current(); MigrationIncomingState *mis = migration_incoming_get_current(); Error *local_err = NULL; int ret; @@ -2909,6 +3073,8 @@ int qemu_loadvm_state(QEMUFile *f) return -EINVAL; } + qemu_loadvm_thread_pool_create(mis); + ret = qemu_loadvm_state_header(f); if (ret) { return ret; @@ -2940,12 +3106,18 @@ int qemu_loadvm_state(QEMUFile *f) /* When reaching here, it must be precopy */ if (ret == 0) { - if (migrate_has_error(migrate_get_current())) { + if (migrate_has_error(migrate_get_current()) || + !qemu_loadvm_thread_pool_wait(s, mis)) { ret = -EINVAL; } else { ret = qemu_file_get_error(f); } } + /* + * Set this flag unconditionally so we'll catch further attempts to + * start additional threads via an appropriate assert() + */ + qatomic_set(&mis->load_threads_abort, true); /* * Try to read in the VMDESC section as well, so that dumping tools that @@ -3021,6 +3193,29 @@ int qemu_loadvm_approve_switchover(void) return migrate_send_rp_switchover_ack(mis); } +bool qemu_loadvm_load_state_buffer(const char *idstr, uint32_t instance_id, + char *buf, size_t len, Error **errp) +{ + SaveStateEntry *se; + + se = find_se(idstr, instance_id); + if (!se) { + error_setg(errp, + "Unknown idstr %s or instance id %u for load state buffer", + idstr, instance_id); + return false; + } + + if (!se->ops || !se->ops->load_state_buffer) { + error_setg(errp, + "idstr %s / instance %u has no load state buffer operation", + idstr, instance_id); + return false; + } + + return se->ops->load_state_buffer(se->opaque, buf, len, errp); +} + bool save_snapshot(const char *name, bool overwrite, const char *vmstate, bool has_devices, strList *devices, Error **errp) { |