diff --git a/migration/ram.c b/migration/ram.c index 76410f9de8..77c66a4391 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -510,6 +510,8 @@ exit: #define MULTIFD_MAGIC 0x11223344U #define MULTIFD_VERSION 1 +#define MULTIFD_FLAG_SYNC (1 << 0) + typedef struct { uint32_t magic; uint32_t version; @@ -577,6 +579,8 @@ typedef struct { uint64_t num_packets; /* pages sent through this channel */ uint64_t num_pages; + /* syncs main thread and channels */ + QemuSemaphore sem_sync; } MultiFDSendParams; typedef struct { @@ -614,6 +618,8 @@ typedef struct { uint64_t num_packets; /* pages sent through this channel */ uint64_t num_pages; + /* syncs main thread and channels */ + QemuSemaphore sem_sync; } MultiFDRecvParams; static int multifd_send_initial_packet(MultiFDSendParams *p, Error **errp) @@ -801,6 +807,10 @@ struct { int count; /* array of pages to sent */ MultiFDPages_t *pages; + /* syncs main thread and channels */ + QemuSemaphore sem_sync; + /* global number of generated multifd packets */ + uint64_t packet_num; } *multifd_send_state; static void multifd_send_terminate_threads(Error *err) @@ -848,6 +858,7 @@ int multifd_save_cleanup(Error **errp) p->c = NULL; qemu_mutex_destroy(&p->mutex); qemu_sem_destroy(&p->sem); + qemu_sem_destroy(&p->sem_sync); g_free(p->name); p->name = NULL; multifd_pages_clear(p->pages); @@ -856,6 +867,7 @@ int multifd_save_cleanup(Error **errp) g_free(p->packet); p->packet = NULL; } + qemu_sem_destroy(&multifd_send_state->sem_sync); g_free(multifd_send_state->params); multifd_send_state->params = NULL; multifd_pages_clear(multifd_send_state->pages); @@ -865,6 +877,33 @@ int multifd_save_cleanup(Error **errp) return ret; } +static void multifd_send_sync_main(void) +{ + int i; + + if (!migrate_use_multifd()) { + return; + } + for (i = 0; i < migrate_multifd_channels(); i++) { + MultiFDSendParams *p = &multifd_send_state->params[i]; + + trace_multifd_send_sync_main_signal(p->id); + + qemu_mutex_lock(&p->mutex); + p->flags |= MULTIFD_FLAG_SYNC; + p->pending_job++; + qemu_mutex_unlock(&p->mutex); + qemu_sem_post(&p->sem); + } + for (i = 0; i < migrate_multifd_channels(); i++) { + MultiFDSendParams *p = &multifd_send_state->params[i]; + + trace_multifd_send_sync_main_wait(p->id); + qemu_sem_wait(&multifd_send_state->sem_sync); + } + trace_multifd_send_sync_main(multifd_send_state->packet_num); +} + static void *multifd_send_thread(void *opaque) { MultiFDSendParams *p = opaque; @@ -901,15 +940,17 @@ static void *multifd_send_thread(void *opaque) qemu_mutex_lock(&p->mutex); p->pending_job--; qemu_mutex_unlock(&p->mutex); - continue; + + if (flags & MULTIFD_FLAG_SYNC) { + qemu_sem_post(&multifd_send_state->sem_sync); + } } else if (p->quit) { qemu_mutex_unlock(&p->mutex); break; + } else { + qemu_mutex_unlock(&p->mutex); + /* sometimes there are spurious wakeups */ } - qemu_mutex_unlock(&p->mutex); - /* this is impossible */ - error_setg(&local_err, "multifd_send_thread: Unknown command"); - break; } out: @@ -961,12 +1002,14 @@ int multifd_save_setup(void) multifd_send_state->params = g_new0(MultiFDSendParams, thread_count); atomic_set(&multifd_send_state->count, 0); multifd_send_state->pages = multifd_pages_init(page_count); + qemu_sem_init(&multifd_send_state->sem_sync, 0); for (i = 0; i < thread_count; i++) { MultiFDSendParams *p = &multifd_send_state->params[i]; qemu_mutex_init(&p->mutex); qemu_sem_init(&p->sem, 0); + qemu_sem_init(&p->sem_sync, 0); p->quit = false; p->pending_job = 0; p->id = i; @@ -984,6 +1027,10 @@ struct { MultiFDRecvParams *params; /* number of created threads */ int count; + /* syncs main thread and channels */ + QemuSemaphore sem_sync; + /* global number of generated multifd packets */ + uint64_t packet_num; } *multifd_recv_state; static void multifd_recv_terminate_threads(Error *err) @@ -1029,6 +1076,7 @@ int multifd_load_cleanup(Error **errp) p->c = NULL; qemu_mutex_destroy(&p->mutex); qemu_sem_destroy(&p->sem); + qemu_sem_destroy(&p->sem_sync); g_free(p->name); p->name = NULL; multifd_pages_clear(p->pages); @@ -1037,6 +1085,7 @@ int multifd_load_cleanup(Error **errp) g_free(p->packet); p->packet = NULL; } + qemu_sem_destroy(&multifd_recv_state->sem_sync); g_free(multifd_recv_state->params); multifd_recv_state->params = NULL; g_free(multifd_recv_state); @@ -1045,6 +1094,42 @@ int multifd_load_cleanup(Error **errp) return ret; } +static void multifd_recv_sync_main(void) +{ + int i; + + if (!migrate_use_multifd()) { + return; + } + for (i = 0; i < migrate_multifd_channels(); i++) { + MultiFDRecvParams *p = &multifd_recv_state->params[i]; + + trace_multifd_recv_sync_main_signal(p->id); + qemu_mutex_lock(&p->mutex); + p->pending_job = true; + qemu_mutex_unlock(&p->mutex); + } + for (i = 0; i < migrate_multifd_channels(); i++) { + MultiFDRecvParams *p = &multifd_recv_state->params[i]; + + trace_multifd_recv_sync_main_wait(p->id); + qemu_sem_wait(&multifd_recv_state->sem_sync); + qemu_mutex_lock(&p->mutex); + if (multifd_recv_state->packet_num < p->packet_num) { + multifd_recv_state->packet_num = p->packet_num; + } + qemu_mutex_unlock(&p->mutex); + } + for (i = 0; i < migrate_multifd_channels(); i++) { + MultiFDRecvParams *p = &multifd_recv_state->params[i]; + + trace_multifd_recv_sync_main_signal(p->id); + + qemu_sem_post(&p->sem_sync); + } + trace_multifd_recv_sync_main(multifd_recv_state->packet_num); +} + static void *multifd_recv_thread(void *opaque) { MultiFDRecvParams *p = opaque; @@ -1054,37 +1139,30 @@ static void *multifd_recv_thread(void *opaque) trace_multifd_recv_thread_start(p->id); while (true) { - qemu_sem_wait(&p->sem); + uint32_t used; + uint32_t flags; + + /* ToDo: recv packet here */ + qemu_mutex_lock(&p->mutex); - if (p->pending_job) { - uint32_t used; - uint32_t flags; - qemu_mutex_unlock(&p->mutex); - - /* ToDo: recv packet here */ - - qemu_mutex_lock(&p->mutex); - ret = multifd_recv_unfill_packet(p, &local_err); - if (ret) { - qemu_mutex_unlock(&p->mutex); - break; - } - - used = p->pages->used; - flags = p->flags; - trace_multifd_recv(p->id, p->packet_num, used, flags); - p->pending_job = false; - p->num_packets++; - p->num_pages += used; - qemu_mutex_unlock(&p->mutex); - } else if (p->quit) { + ret = multifd_recv_unfill_packet(p, &local_err); + if (ret) { qemu_mutex_unlock(&p->mutex); break; } + + used = p->pages->used; + flags = p->flags; + trace_multifd_recv(p->id, p->packet_num, used, flags); + p->pending_job = false; + p->num_packets++; + p->num_pages += used; qemu_mutex_unlock(&p->mutex); - /* this is impossible */ - error_setg(&local_err, "multifd_recv_thread: Unknown command"); - break; + + if (flags & MULTIFD_FLAG_SYNC) { + qemu_sem_post(&multifd_recv_state->sem_sync); + qemu_sem_wait(&p->sem_sync); + } } if (local_err) { @@ -1112,12 +1190,14 @@ int multifd_load_setup(void) multifd_recv_state = g_malloc0(sizeof(*multifd_recv_state)); multifd_recv_state->params = g_new0(MultiFDRecvParams, thread_count); atomic_set(&multifd_recv_state->count, 0); + qemu_sem_init(&multifd_recv_state->sem_sync, 0); for (i = 0; i < thread_count; i++) { MultiFDRecvParams *p = &multifd_recv_state->params[i]; qemu_mutex_init(&p->mutex); qemu_sem_init(&p->sem, 0); + qemu_sem_init(&p->sem_sync, 0); p->quit = false; p->pending_job = false; p->id = i; @@ -2875,6 +2955,7 @@ static int ram_save_setup(QEMUFile *f, void *opaque) ram_control_before_iterate(f, RAM_CONTROL_SETUP); ram_control_after_iterate(f, RAM_CONTROL_SETUP); + multifd_send_sync_main(); qemu_put_be64(f, RAM_SAVE_FLAG_EOS); return 0; @@ -2955,6 +3036,7 @@ static int ram_save_iterate(QEMUFile *f, void *opaque) */ ram_control_after_iterate(f, RAM_CONTROL_ROUND); + multifd_send_sync_main(); out: qemu_put_be64(f, RAM_SAVE_FLAG_EOS); ram_counters.transferred += 8; @@ -3008,6 +3090,7 @@ static int ram_save_complete(QEMUFile *f, void *opaque) rcu_read_unlock(); + multifd_send_sync_main(); qemu_put_be64(f, RAM_SAVE_FLAG_EOS); return 0; @@ -3497,6 +3580,7 @@ static int ram_load_postcopy(QEMUFile *f) break; case RAM_SAVE_FLAG_EOS: /* normal exit */ + multifd_recv_sync_main(); break; default: error_report("Unknown combination of migration flags: %#x" @@ -3685,6 +3769,7 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id) break; case RAM_SAVE_FLAG_EOS: /* normal exit */ + multifd_recv_sync_main(); break; default: if (flags & RAM_SAVE_FLAG_HOOK) { diff --git a/migration/trace-events b/migration/trace-events index 4aad26feed..8b9edfbfef 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -77,9 +77,15 @@ migration_bitmap_sync_start(void) "" migration_bitmap_sync_end(uint64_t dirty_pages) "dirty_pages %" PRIu64 migration_throttle(void) "" multifd_recv(uint8_t id, uint64_t packet_num, uint32_t used, uint32_t flags) "channel %d packet number %" PRIu64 " pages %d flags 0x%x" +multifd_recv_sync_main(long packet_num) "packet num %ld" +multifd_recv_sync_main_signal(uint8_t id) "channel %d" +multifd_recv_sync_main_wait(uint8_t id) "channel %d" multifd_recv_thread_end(uint8_t id, uint64_t packets, uint64_t pages) "channel %d packets %" PRIu64 " pages %" PRIu64 multifd_recv_thread_start(uint8_t id) "%d" multifd_send(uint8_t id, uint64_t packet_num, uint32_t used, uint32_t flags) "channel %d packet_num %" PRIu64 " pages %d flags 0x%x" +multifd_send_sync_main(long packet_num) "packet num %ld" +multifd_send_sync_main_signal(uint8_t id) "channel %d" +multifd_send_sync_main_wait(uint8_t id) "channel %d" multifd_send_thread_end(uint8_t id, uint64_t packets, uint64_t pages) "channel %d packets %" PRIu64 " pages %" PRIu64 multifd_send_thread_start(uint8_t id) "%d" ram_discard_range(const char *rbname, uint64_t start, size_t len) "%s: start: %" PRIx64 " %zx"