diff --git a/migration/exec.c b/migration/exec.c index 0bbeb63c97e548c4d1fa541dac37c57c34df6493..375d2e1b54c421646e613b56efe6511c5c789e7f 100644 --- a/migration/exec.c +++ b/migration/exec.c @@ -49,9 +49,6 @@ static gboolean exec_accept_incoming_migration(QIOChannel *ioc, { migration_channel_process_incoming(ioc); object_unref(OBJECT(ioc)); - if (!migrate_use_multifd()) { - migration_incoming_process(); - } return G_SOURCE_REMOVE; } diff --git a/migration/fd.c b/migration/fd.c index fee34ffdc0a3ccba08d0d280852d556e17594d29..a7c13df4ad3e7ad685ddb3ec01b6373d5003d192 100644 --- a/migration/fd.c +++ b/migration/fd.c @@ -49,9 +49,6 @@ static gboolean fd_accept_incoming_migration(QIOChannel *ioc, { migration_channel_process_incoming(ioc); object_unref(OBJECT(ioc)); - if (!migrate_use_multifd()) { - migration_incoming_process(); - } return G_SOURCE_REMOVE; } diff --git a/migration/migration.c b/migration/migration.c index 94d71f8b24ca21f035aa4e54ad7e1f9af569dd5a..8d56d5693052b5e78b7deca92f575f91641176f7 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -466,7 +466,8 @@ void migration_incoming_process(void) qemu_coroutine_enter(co); } -void migration_fd_process_incoming(QEMUFile *f) +/* Returns true if recovered from a paused migration, otherwise false */ +static bool postcopy_try_recover(QEMUFile *f) { MigrationIncomingState *mis = migration_incoming_get_current(); @@ -491,23 +492,52 @@ void migration_fd_process_incoming(QEMUFile *f) * that source is ready to reply to page requests. */ qemu_sem_post(&mis->postcopy_pause_sem_dst); - } else { - /* New incoming migration */ - migration_incoming_setup(f); - migration_incoming_process(); + return true; + } + + return false; +} + +void migration_fd_process_incoming(QEMUFile *f) +{ + if (postcopy_try_recover(f)) { + return; } + + migration_incoming_setup(f); + migration_incoming_process(); } void migration_ioc_process_incoming(QIOChannel *ioc) { MigrationIncomingState *mis = migration_incoming_get_current(); + bool start_migration; if (!mis->from_src_file) { + /* The first connection (multifd may have multiple) */ QEMUFile *f = qemu_fopen_channel_input(ioc); + + /* If it's a recovery, we're done */ + if (postcopy_try_recover(f)) { + return; + } + migration_incoming_setup(f); - return; + + /* + * Common migration only needs one channel, so we can start + * right now. Multifd needs more than one channel, we wait. + */ + start_migration = !migrate_use_multifd(); + } else { + /* Multiple connections */ + assert(migrate_use_multifd()); + start_migration = multifd_recv_new_channel(ioc); + } + + if (start_migration) { + migration_incoming_process(); } - multifd_recv_new_channel(ioc); } /** @@ -881,6 +911,8 @@ static void fill_destination_migration_info(MigrationInfo *info) case MIGRATION_STATUS_CANCELLED: case MIGRATION_STATUS_ACTIVE: case MIGRATION_STATUS_POSTCOPY_ACTIVE: + case MIGRATION_STATUS_POSTCOPY_PAUSED: + case MIGRATION_STATUS_POSTCOPY_RECOVER: case MIGRATION_STATUS_FAILED: case MIGRATION_STATUS_COLO: info->has_status = true; diff --git a/migration/ram.c b/migration/ram.c index 1cd98d6398a7d6fff53ad46ea79c20b064b25ec2..52dd678092ee66ddbf27785b647f5498fa98f072 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -235,7 +235,7 @@ int64_t ramblock_recv_bitmap_send(QEMUFile *file, bitmap_to_le(le_bitmap, block->receivedmap, nbits); /* Size of the bitmap, in bytes */ - size = nbits / 8; + size = DIV_ROUND_UP(nbits, 8); /* * size is always aligned to 8 bytes for 64bit machines, but it @@ -1311,7 +1311,8 @@ bool multifd_recv_all_channels_created(void) return thread_count == atomic_read(&multifd_recv_state->count); } -void multifd_recv_new_channel(QIOChannel *ioc) +/* Return true if multifd is ready for the migration, otherwise false */ +bool multifd_recv_new_channel(QIOChannel *ioc) { MultiFDRecvParams *p; Error *local_err = NULL; @@ -1320,7 +1321,7 @@ void multifd_recv_new_channel(QIOChannel *ioc) id = multifd_recv_initial_packet(ioc, &local_err); if (id < 0) { multifd_recv_terminate_threads(local_err); - return; + return false; } p = &multifd_recv_state->params[id]; @@ -1328,7 +1329,7 @@ void multifd_recv_new_channel(QIOChannel *ioc) error_setg(&local_err, "multifd: received id '%d' already setup'", id); multifd_recv_terminate_threads(local_err); - return; + return false; } p->c = ioc; object_ref(OBJECT(ioc)); @@ -1339,9 +1340,7 @@ void multifd_recv_new_channel(QIOChannel *ioc) qemu_thread_create(&p->thread, p->name, multifd_recv_thread, p, QEMU_THREAD_JOINABLE); atomic_inc(&multifd_recv_state->count); - if (multifd_recv_state->count == migrate_multifd_channels()) { - migration_incoming_process(); - } + return multifd_recv_state->count == migrate_multifd_channels(); } /** @@ -3581,7 +3580,7 @@ static int ram_load_postcopy(QEMUFile *f) { int flags = 0, ret = 0; bool place_needed = false; - bool matching_page_sizes = false; + bool matches_target_page_size = false; MigrationIncomingState *mis = migration_incoming_get_current(); /* Temporary page that is later 'placed' */ void *postcopy_host_page = postcopy_get_tmp_page(mis); @@ -3621,7 +3620,7 @@ static int ram_load_postcopy(QEMUFile *f) ret = -EINVAL; break; } - matching_page_sizes = block->page_size == TARGET_PAGE_SIZE; + matches_target_page_size = block->page_size == TARGET_PAGE_SIZE; /* * Postcopy requires that we place whole host pages atomically; * these may be huge pages for RAMBlocks that are backed by @@ -3669,12 +3668,17 @@ static int ram_load_postcopy(QEMUFile *f) case RAM_SAVE_FLAG_PAGE: all_zero = false; - if (!place_needed || !matching_page_sizes) { + if (!matches_target_page_size) { + /* For huge pages, we always use temporary buffer */ qemu_get_buffer(f, page_buffer, TARGET_PAGE_SIZE); } else { - /* Avoids the qemu_file copy during postcopy, which is - * going to do a copy later; can only do it when we - * do this read in one go (matching page sizes) + /* + * For small pages that matches target page size, we + * avoid the qemu_file copy. Instead we directly use + * the buffer of QEMUFile to place the page. Note: we + * cannot do any QEMUFile operation before using that + * buffer to make sure the buffer is valid when + * placing the page. */ qemu_get_buffer_in_place(f, (uint8_t **)&place_source, TARGET_PAGE_SIZE); @@ -3940,7 +3944,7 @@ int ram_dirty_bitmap_reload(MigrationState *s, RAMBlock *block) int ret = -EINVAL; QEMUFile *file = s->rp_state.from_dst_file; unsigned long *le_bitmap, nbits = block->used_length >> TARGET_PAGE_BITS; - uint64_t local_size = nbits / 8; + uint64_t local_size = DIV_ROUND_UP(nbits, 8); uint64_t size, end_mark; trace_ram_dirty_bitmap_reload_begin(block->idstr); diff --git a/migration/ram.h b/migration/ram.h index d386f4d641ada3d0c03b99221be04db11b7183e4..457bf54b8c130b9044ab3ab079d92162f30b050e 100644 --- a/migration/ram.h +++ b/migration/ram.h @@ -46,7 +46,7 @@ int multifd_save_cleanup(Error **errp); int multifd_load_setup(void); int multifd_load_cleanup(Error **errp); bool multifd_recv_all_channels_created(void); -void multifd_recv_new_channel(QIOChannel *ioc); +bool multifd_recv_new_channel(QIOChannel *ioc); uint64_t ram_pagesize_summary(void); int ram_save_queue_pages(const char *rbname, ram_addr_t start, ram_addr_t len); diff --git a/migration/savevm.c b/migration/savevm.c index c2f34ffc7cd7df031d203daa8e34f4fce7943810..7f92567a10bd10b52cba1db37de29bc81bb83681 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -81,8 +81,8 @@ enum qemu_vm_cmd { MIG_CMD_POSTCOPY_RAM_DISCARD, /* A list of pages to discard that were previously sent during precopy but are dirty. */ - MIG_CMD_POSTCOPY_RESUME, /* resume postcopy on dest */ MIG_CMD_PACKAGED, /* Send a wrapped stream within this stream */ + MIG_CMD_POSTCOPY_RESUME, /* resume postcopy on dest */ MIG_CMD_RECV_BITMAP, /* Request for recved bitmap on dst */ MIG_CMD_MAX }; @@ -2194,9 +2194,6 @@ static bool postcopy_pause_incoming(MigrationIncomingState *mis) /* Clear the triggered bit to allow one recovery */ mis->postcopy_recover_triggered = false; - migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, - MIGRATION_STATUS_POSTCOPY_PAUSED); - assert(mis->from_src_file); qemu_file_shutdown(mis->from_src_file); qemu_fclose(mis->from_src_file); @@ -2209,6 +2206,9 @@ static bool postcopy_pause_incoming(MigrationIncomingState *mis) mis->to_src_file = NULL; qemu_mutex_unlock(&mis->rp_mutex); + migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, + MIGRATION_STATUS_POSTCOPY_PAUSED); + /* Notify the fault thread for the invalidated file handle */ postcopy_fault_thread_notify(mis); @@ -2276,18 +2276,14 @@ out: qemu_file_set_error(f, ret); /* - * Detect whether it is: - * - * 1. postcopy running (after receiving all device data, which - * must be in POSTCOPY_INCOMING_RUNNING state. Note that - * POSTCOPY_INCOMING_LISTENING is still not enough, it's - * still receiving device states). - * 2. network failure (-EIO) - * - * If so, we try to wait for a recovery. + * If we are during an active postcopy, then we pause instead + * of bail out to at least keep the VM's dirty data. Note + * that POSTCOPY_INCOMING_LISTENING stage is still not enough, + * during which we're still receiving device states and we + * still haven't yet started the VM on destination. */ if (postcopy_state_get() == POSTCOPY_INCOMING_RUNNING && - ret == -EIO && postcopy_pause_incoming(mis)) { + postcopy_pause_incoming(mis)) { /* Reset f to point to the newly created channel */ f = mis->from_src_file; goto retry; diff --git a/migration/socket.c b/migration/socket.c index 3456eb76e9309fca3c587ddf9190beb4efc4f395..f4c8174400563f42ca15366d3a60b35ec8c706a0 100644 --- a/migration/socket.c +++ b/migration/socket.c @@ -168,12 +168,7 @@ static void socket_accept_incoming_migration(QIONetListener *listener, if (migration_has_all_channels()) { /* Close listening socket as its no longer needed */ qio_net_listener_disconnect(listener); - object_unref(OBJECT(listener)); - - if (!migrate_use_multifd()) { - migration_incoming_process(); - } } } diff --git a/tests/migration-test.c b/tests/migration-test.c index 331efb0fe5d358a89f0d106470184ef64e7861f3..086f727b34e9f4d9bdd49817075ce8bb88e2ce08 100644 --- a/tests/migration-test.c +++ b/tests/migration-test.c @@ -168,6 +168,37 @@ static QDict *wait_command(QTestState *who, const char *command) return response; } +/* + * Note: caller is responsible to free the returned object via + * qobject_unref() after use + */ +static QDict *migrate_query(QTestState *who) +{ + QDict *rsp, *rsp_return; + + rsp = wait_command(who, "{ 'execute': 'query-migrate' }"); + rsp_return = qdict_get_qdict(rsp, "return"); + g_assert(rsp_return); + qobject_ref(rsp_return); + qobject_unref(rsp); + + return rsp_return; +} + +/* + * Note: caller is responsible to free the returned object via + * g_free() after use + */ +static gchar *migrate_query_status(QTestState *who) +{ + QDict *rsp_return = migrate_query(who); + gchar *status = g_strdup(qdict_get_str(rsp_return, "status")); + + g_assert(status); + qobject_unref(rsp_return); + + return status; +} /* * It's tricky to use qemu's migration event capability with qtest, @@ -176,11 +207,10 @@ static QDict *wait_command(QTestState *who, const char *command) static uint64_t get_migration_pass(QTestState *who) { - QDict *rsp, *rsp_return, *rsp_ram; + QDict *rsp_return, *rsp_ram; uint64_t result; - rsp = wait_command(who, "{ 'execute': 'query-migrate' }"); - rsp_return = qdict_get_qdict(rsp, "return"); + rsp_return = migrate_query(who); if (!qdict_haskey(rsp_return, "ram")) { /* Still in setup */ result = 0; @@ -188,33 +218,30 @@ static uint64_t get_migration_pass(QTestState *who) rsp_ram = qdict_get_qdict(rsp_return, "ram"); result = qdict_get_try_int(rsp_ram, "dirty-sync-count", 0); } - qobject_unref(rsp); + qobject_unref(rsp_return); return result; } static void read_blocktime(QTestState *who) { - QDict *rsp, *rsp_return; + QDict *rsp_return; - rsp = wait_command(who, "{ 'execute': 'query-migrate' }"); - rsp_return = qdict_get_qdict(rsp, "return"); + rsp_return = migrate_query(who); g_assert(qdict_haskey(rsp_return, "postcopy-blocktime")); - qobject_unref(rsp); + qobject_unref(rsp_return); } -static void wait_for_migration_complete(QTestState *who) +static void wait_for_migration_status(QTestState *who, + const char *goal) { while (true) { - QDict *rsp, *rsp_return; bool completed; - const char *status; + char *status; - rsp = wait_command(who, "{ 'execute': 'query-migrate' }"); - rsp_return = qdict_get_qdict(rsp, "return"); - status = qdict_get_str(rsp_return, "status"); - completed = strcmp(status, "completed") == 0; + status = migrate_query_status(who); + completed = strcmp(status, goal) == 0; g_assert_cmpstr(status, !=, "failed"); - qobject_unref(rsp); + g_free(status); if (completed) { return; } @@ -222,6 +249,11 @@ static void wait_for_migration_complete(QTestState *who) } } +static void wait_for_migration_complete(QTestState *who) +{ + wait_for_migration_status(who, "completed"); +} + static void wait_for_migration_pass(QTestState *who) { uint64_t initial_pass = get_migration_pass(who); @@ -320,6 +352,29 @@ static void migrate_set_parameter(QTestState *who, const char *parameter, migrate_check_parameter(who, parameter, value); } +static void migrate_pause(QTestState *who) +{ + QDict *rsp; + + rsp = wait_command(who, "{ 'execute': 'migrate-pause' }"); + g_assert(qdict_haskey(rsp, "return")); + qobject_unref(rsp); +} + +static void migrate_recover(QTestState *who, const char *uri) +{ + QDict *rsp; + gchar *cmd = g_strdup_printf( + "{ 'execute': 'migrate-recover', " + " 'id': 'recover-cmd', " + " 'arguments': { 'uri': '%s' } }", uri); + + rsp = wait_command(who, cmd); + g_assert(qdict_haskey(rsp, "return")); + g_free(cmd); + qobject_unref(rsp); +} + static void migrate_set_capability(QTestState *who, const char *capability, const char *value) { @@ -337,27 +392,33 @@ static void migrate_set_capability(QTestState *who, const char *capability, qobject_unref(rsp); } -static void migrate(QTestState *who, const char *uri) +static void migrate(QTestState *who, const char *uri, const char *extra) { QDict *rsp; gchar *cmd; cmd = g_strdup_printf("{ 'execute': 'migrate'," - "'arguments': { 'uri': '%s' } }", - uri); + " 'arguments': { 'uri': '%s' %s } }", + uri, extra ? extra : ""); rsp = qtest_qmp(who, cmd); g_free(cmd); g_assert(qdict_haskey(rsp, "return")); qobject_unref(rsp); } -static void migrate_start_postcopy(QTestState *who) +static void migrate_postcopy_start(QTestState *from, QTestState *to) { QDict *rsp; - rsp = wait_command(who, "{ 'execute': 'migrate-start-postcopy' }"); + rsp = wait_command(from, "{ 'execute': 'migrate-start-postcopy' }"); g_assert(qdict_haskey(rsp, "return")); qobject_unref(rsp); + + if (!got_stop) { + qtest_qmp_eventwait(from, "STOP"); + } + + qtest_qmp_eventwait(to, "RESUME"); } static int test_migrate_start(QTestState **from, QTestState **to, @@ -510,13 +571,15 @@ static void test_deprecated(void) qtest_quit(from); } -static void test_postcopy(void) +static int migrate_postcopy_prepare(QTestState **from_ptr, + QTestState **to_ptr, + bool hide_error) { char *uri = g_strdup_printf("unix:%s/migsocket", tmpfs); QTestState *from, *to; - if (test_migrate_start(&from, &to, uri, false)) { - return; + if (test_migrate_start(&from, &to, uri, hide_error)) { + return -1; } migrate_set_capability(from, "postcopy-ram", "true"); @@ -533,49 +596,114 @@ static void test_postcopy(void) /* Wait for the first serial output from the source */ wait_for_serial("src_serial"); - migrate(from, uri); + migrate(from, uri, NULL); + g_free(uri); wait_for_migration_pass(from); - migrate_start_postcopy(from); + *from_ptr = from; + *to_ptr = to; - if (!got_stop) { - qtest_qmp_eventwait(from, "STOP"); - } + return 0; +} - qtest_qmp_eventwait(to, "RESUME"); +static void migrate_postcopy_complete(QTestState *from, QTestState *to) +{ + wait_for_migration_complete(from); + /* Make sure we get at least one "B" on destination */ wait_for_serial("dest_serial"); - wait_for_migration_complete(from); if (uffd_feature_thread_id) { read_blocktime(to); } - g_free(uri); test_migrate_end(from, to, true); } +static void test_postcopy(void) +{ + QTestState *from, *to; + + if (migrate_postcopy_prepare(&from, &to, false)) { + return; + } + migrate_postcopy_start(from, to); + migrate_postcopy_complete(from, to); +} + +static void test_postcopy_recovery(void) +{ + QTestState *from, *to; + char *uri; + + if (migrate_postcopy_prepare(&from, &to, true)) { + return; + } + + /* Turn postcopy speed down, 4K/s is slow enough on any machines */ + migrate_set_parameter(from, "max-postcopy-bandwidth", "4096"); + + /* Now we start the postcopy */ + migrate_postcopy_start(from, to); + + /* + * Wait until postcopy is really started; we can only run the + * migrate-pause command during a postcopy + */ + wait_for_migration_status(from, "postcopy-active"); + + /* + * Manually stop the postcopy migration. This emulates a network + * failure with the migration socket + */ + migrate_pause(from); + + /* + * Wait for destination side to reach postcopy-paused state. The + * migrate-recover command can only succeed if destination machine + * is in the paused state + */ + wait_for_migration_status(to, "postcopy-paused"); + + /* + * Create a new socket to emulate a new channel that is different + * from the broken migration channel; tell the destination to + * listen to the new port + */ + uri = g_strdup_printf("unix:%s/migsocket-recover", tmpfs); + migrate_recover(to, uri); + + /* + * Try to rebuild the migration channel using the resume flag and + * the newly created channel + */ + wait_for_migration_status(from, "postcopy-paused"); + migrate(from, uri, ", 'resume': true"); + g_free(uri); + + /* Restore the postcopy bandwidth to unlimited */ + migrate_set_parameter(from, "max-postcopy-bandwidth", "0"); + + migrate_postcopy_complete(from, to); +} + static void test_baddest(void) { QTestState *from, *to; QDict *rsp, *rsp_return; - const char *status; + char *status; bool failed; if (test_migrate_start(&from, &to, "tcp:0:0", true)) { return; } - migrate(from, "tcp:0:0"); + migrate(from, "tcp:0:0", NULL); do { - rsp = wait_command(from, "{ 'execute': 'query-migrate' }"); - rsp_return = qdict_get_qdict(rsp, "return"); - - status = qdict_get_str(rsp_return, "status"); - + status = migrate_query_status(from); g_assert(!strcmp(status, "setup") || !(strcmp(status, "failed"))); failed = !strcmp(status, "failed"); - qobject_unref(rsp); + g_free(status); } while (!failed); /* Is the machine currently running? */ @@ -610,7 +738,7 @@ static void test_precopy_unix(void) /* Wait for the first serial output from the source */ wait_for_serial("src_serial"); - migrate(from, uri); + migrate(from, uri, NULL); wait_for_migration_pass(from); @@ -650,6 +778,7 @@ int main(int argc, char **argv) module_call_init(MODULE_INIT_QOM); qtest_add_func("/migration/postcopy/unix", test_postcopy); + qtest_add_func("/migration/postcopy/recovery", test_postcopy_recovery); qtest_add_func("/migration/deprecated", test_deprecated); qtest_add_func("/migration/bad_dest", test_baddest); qtest_add_func("/migration/precopy/unix", test_precopy_unix);