@@ -7,6 +7,7 @@ common-obj-y += qemu-file-channel.o
common-obj-y += xbzrle.o postcopy-ram.o
common-obj-y += qjson.o
common-obj-y += block-dirty-bitmap.o
+common-obj-y += multifd.o
common-obj-$(CONFIG_RDMA) += rdma.o
@@ -53,6 +53,7 @@
#include "monitor/monitor.h"
#include "net/announce.h"
#include "qemu/queue.h"
+#include "multifd.h"
#define MAX_THROTTLE (32 << 20) /* Migration transfer speed throttling */
new file mode 100644
@@ -0,0 +1,899 @@
+/*
+ * Multifd common code
+ *
+ * Copyright (c) 2019-2020 Red Hat Inc
+ *
+ * Authors:
+ * Juan Quintela <quintela@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/rcu.h"
+#include "exec/target_page.h"
+#include "sysemu/sysemu.h"
+#include "exec/ramblock.h"
+#include "qemu/error-report.h"
+#include "qapi/error.h"
+#include "ram.h"
+#include "migration.h"
+#include "socket.h"
+#include "qemu-file.h"
+#include "trace.h"
+#include "multifd.h"
+
+/* Multiple fd's */
+
+#define MULTIFD_MAGIC 0x11223344U
+#define MULTIFD_VERSION 1
+
+typedef struct {
+ uint32_t magic;
+ uint32_t version;
+ unsigned char uuid[16]; /* QemuUUID */
+ uint8_t id;
+ uint8_t unused1[7]; /* Reserved for future use */
+ uint64_t unused2[4]; /* Reserved for future use */
+} __attribute__((packed)) MultiFDInit_t;
+
+static int multifd_send_initial_packet(MultiFDSendParams *p, Error **errp)
+{
+ MultiFDInit_t msg = {};
+ int ret;
+
+ msg.magic = cpu_to_be32(MULTIFD_MAGIC);
+ msg.version = cpu_to_be32(MULTIFD_VERSION);
+ msg.id = p->id;
+ memcpy(msg.uuid, &qemu_uuid.data, sizeof(msg.uuid));
+
+ ret = qio_channel_write_all(p->c, (char *)&msg, sizeof(msg), errp);
+ if (ret != 0) {
+ return -1;
+ }
+ return 0;
+}
+
+static int multifd_recv_initial_packet(QIOChannel *c, Error **errp)
+{
+ MultiFDInit_t msg;
+ int ret;
+
+ ret = qio_channel_read_all(c, (char *)&msg, sizeof(msg), errp);
+ if (ret != 0) {
+ return -1;
+ }
+
+ msg.magic = be32_to_cpu(msg.magic);
+ msg.version = be32_to_cpu(msg.version);
+
+ if (msg.magic != MULTIFD_MAGIC) {
+ error_setg(errp, "multifd: received packet magic %x "
+ "expected %x", msg.magic, MULTIFD_MAGIC);
+ return -1;
+ }
+
+ if (msg.version != MULTIFD_VERSION) {
+ error_setg(errp, "multifd: received packet version %d "
+ "expected %d", msg.version, MULTIFD_VERSION);
+ return -1;
+ }
+
+ if (memcmp(msg.uuid, &qemu_uuid, sizeof(qemu_uuid))) {
+ char *uuid = qemu_uuid_unparse_strdup(&qemu_uuid);
+ char *msg_uuid = qemu_uuid_unparse_strdup((const QemuUUID *)msg.uuid);
+
+ error_setg(errp, "multifd: received uuid '%s' and expected "
+ "uuid '%s' for channel %hhd", msg_uuid, uuid, msg.id);
+ g_free(uuid);
+ g_free(msg_uuid);
+ return -1;
+ }
+
+ if (msg.id > migrate_multifd_channels()) {
+ error_setg(errp, "multifd: received channel version %d "
+ "expected %d", msg.version, MULTIFD_VERSION);
+ return -1;
+ }
+
+ return msg.id;
+}
+
+static MultiFDPages_t *multifd_pages_init(size_t size)
+{
+ MultiFDPages_t *pages = g_new0(MultiFDPages_t, 1);
+
+ pages->allocated = size;
+ pages->iov = g_new0(struct iovec, size);
+ pages->offset = g_new0(ram_addr_t, size);
+
+ return pages;
+}
+
+static void multifd_pages_clear(MultiFDPages_t *pages)
+{
+ pages->used = 0;
+ pages->allocated = 0;
+ pages->packet_num = 0;
+ pages->block = NULL;
+ g_free(pages->iov);
+ pages->iov = NULL;
+ g_free(pages->offset);
+ pages->offset = NULL;
+ g_free(pages);
+}
+
+static void multifd_send_fill_packet(MultiFDSendParams *p)
+{
+ MultiFDPacket_t *packet = p->packet;
+ int i;
+
+ packet->flags = cpu_to_be32(p->flags);
+ packet->pages_alloc = cpu_to_be32(p->pages->allocated);
+ packet->pages_used = cpu_to_be32(p->pages->used);
+ packet->next_packet_size = cpu_to_be32(p->next_packet_size);
+ packet->packet_num = cpu_to_be64(p->packet_num);
+
+ if (p->pages->block) {
+ strncpy(packet->ramblock, p->pages->block->idstr, 256);
+ }
+
+ for (i = 0; i < p->pages->used; i++) {
+ /* there are architectures where ram_addr_t is 32 bit */
+ uint64_t temp = p->pages->offset[i];
+
+ packet->offset[i] = cpu_to_be64(temp);
+ }
+}
+
+static int multifd_recv_unfill_packet(MultiFDRecvParams *p, Error **errp)
+{
+ MultiFDPacket_t *packet = p->packet;
+ uint32_t pages_max = MULTIFD_PACKET_SIZE / qemu_target_page_size();
+ RAMBlock *block;
+ int i;
+
+ packet->magic = be32_to_cpu(packet->magic);
+ if (packet->magic != MULTIFD_MAGIC) {
+ error_setg(errp, "multifd: received packet "
+ "magic %x and expected magic %x",
+ packet->magic, MULTIFD_MAGIC);
+ return -1;
+ }
+
+ packet->version = be32_to_cpu(packet->version);
+ if (packet->version != MULTIFD_VERSION) {
+ error_setg(errp, "multifd: received packet "
+ "version %d and expected version %d",
+ packet->version, MULTIFD_VERSION);
+ return -1;
+ }
+
+ p->flags = be32_to_cpu(packet->flags);
+
+ packet->pages_alloc = be32_to_cpu(packet->pages_alloc);
+ /*
+ * If we received a packet that is 100 times bigger than expected
+ * just stop migration. It is a magic number.
+ */
+ if (packet->pages_alloc > pages_max * 100) {
+ error_setg(errp, "multifd: received packet "
+ "with size %d and expected a maximum size of %d",
+ packet->pages_alloc, pages_max * 100) ;
+ return -1;
+ }
+ /*
+ * We received a packet that is bigger than expected but inside
+ * reasonable limits (see previous comment). Just reallocate.
+ */
+ if (packet->pages_alloc > p->pages->allocated) {
+ multifd_pages_clear(p->pages);
+ p->pages = multifd_pages_init(packet->pages_alloc);
+ }
+
+ p->pages->used = be32_to_cpu(packet->pages_used);
+ if (p->pages->used > packet->pages_alloc) {
+ error_setg(errp, "multifd: received packet "
+ "with %d pages and expected maximum pages are %d",
+ p->pages->used, packet->pages_alloc) ;
+ return -1;
+ }
+
+ p->next_packet_size = be32_to_cpu(packet->next_packet_size);
+ p->packet_num = be64_to_cpu(packet->packet_num);
+
+ if (p->pages->used == 0) {
+ return 0;
+ }
+
+ /* make sure that ramblock is 0 terminated */
+ packet->ramblock[255] = 0;
+ block = qemu_ram_block_by_name(packet->ramblock);
+ if (!block) {
+ error_setg(errp, "multifd: unknown ram block %s",
+ packet->ramblock);
+ return -1;
+ }
+
+ for (i = 0; i < p->pages->used; i++) {
+ uint64_t offset = be64_to_cpu(packet->offset[i]);
+
+ if (offset > (block->used_length - qemu_target_page_size())) {
+ error_setg(errp, "multifd: offset too long %" PRIu64
+ " (max " RAM_ADDR_FMT ")",
+ offset, block->max_length);
+ return -1;
+ }
+ p->pages->iov[i].iov_base = block->host + offset;
+ p->pages->iov[i].iov_len = qemu_target_page_size();
+ }
+
+ return 0;
+}
+
+struct {
+ MultiFDSendParams *params;
+ /* array of pages to sent */
+ MultiFDPages_t *pages;
+ /* global number of generated multifd packets */
+ uint64_t packet_num;
+ /* send channels ready */
+ QemuSemaphore channels_ready;
+ /*
+ * Have we already run terminate threads. There is a race when it
+ * happens that we got one error while we are exiting.
+ * We will use atomic operations. Only valid values are 0 and 1.
+ */
+ int exiting;
+} *multifd_send_state;
+
+/*
+ * How we use multifd_send_state->pages and channel->pages?
+ *
+ * We create a pages for each channel, and a main one. Each time that
+ * we need to send a batch of pages we interchange the ones between
+ * multifd_send_state and the channel that is sending it. There are
+ * two reasons for that:
+ * - to not have to do so many mallocs during migration
+ * - to make easier to know what to free at the end of migration
+ *
+ * This way we always know who is the owner of each "pages" struct,
+ * and we don't need any locking. It belongs to the migration thread
+ * or to the channel thread. Switching is safe because the migration
+ * thread is using the channel mutex when changing it, and the channel
+ * have to had finish with its own, otherwise pending_job can't be
+ * false.
+ */
+
+static int multifd_send_pages(QEMUFile *f)
+{
+ int i;
+ static int next_channel;
+ MultiFDSendParams *p = NULL; /* make happy gcc */
+ MultiFDPages_t *pages = multifd_send_state->pages;
+ uint64_t transferred;
+
+ if (atomic_read(&multifd_send_state->exiting)) {
+ return -1;
+ }
+
+ qemu_sem_wait(&multifd_send_state->channels_ready);
+ for (i = next_channel;; i = (i + 1) % migrate_multifd_channels()) {
+ p = &multifd_send_state->params[i];
+
+ qemu_mutex_lock(&p->mutex);
+ if (p->quit) {
+ error_report("%s: channel %d has already quit!", __func__, i);
+ qemu_mutex_unlock(&p->mutex);
+ return -1;
+ }
+ if (!p->pending_job) {
+ p->pending_job++;
+ next_channel = (i + 1) % migrate_multifd_channels();
+ break;
+ }
+ qemu_mutex_unlock(&p->mutex);
+ }
+ assert(!p->pages->used);
+ assert(!p->pages->block);
+
+ p->packet_num = multifd_send_state->packet_num++;
+ multifd_send_state->pages = p->pages;
+ p->pages = pages;
+ transferred = ((uint64_t) pages->used) * qemu_target_page_size()
+ + p->packet_len;
+ qemu_file_update_transfer(f, transferred);
+ ram_counters.multifd_bytes += transferred;
+ ram_counters.transferred += transferred;;
+ qemu_mutex_unlock(&p->mutex);
+ qemu_sem_post(&p->sem);
+
+ return 1;
+}
+
+int multifd_queue_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset)
+{
+ MultiFDPages_t *pages = multifd_send_state->pages;
+
+ if (!pages->block) {
+ pages->block = block;
+ }
+
+ if (pages->block == block) {
+ pages->offset[pages->used] = offset;
+ pages->iov[pages->used].iov_base = block->host + offset;
+ pages->iov[pages->used].iov_len = qemu_target_page_size();
+ pages->used++;
+
+ if (pages->used < pages->allocated) {
+ return 1;
+ }
+ }
+
+ if (multifd_send_pages(f) < 0) {
+ return -1;
+ }
+
+ if (pages->block != block) {
+ return multifd_queue_page(f, block, offset);
+ }
+
+ return 1;
+}
+
+static void multifd_send_terminate_threads(Error *err)
+{
+ int i;
+
+ trace_multifd_send_terminate_threads(err != NULL);
+
+ if (err) {
+ MigrationState *s = migrate_get_current();
+ migrate_set_error(s, err);
+ if (s->state == MIGRATION_STATUS_SETUP ||
+ s->state == MIGRATION_STATUS_PRE_SWITCHOVER ||
+ s->state == MIGRATION_STATUS_DEVICE ||
+ s->state == MIGRATION_STATUS_ACTIVE) {
+ migrate_set_state(&s->state, s->state,
+ MIGRATION_STATUS_FAILED);
+ }
+ }
+
+ /*
+ * We don't want to exit each threads twice. Depending on where
+ * we get the error, or if there are two independent errors in two
+ * threads at the same time, we can end calling this function
+ * twice.
+ */
+ if (atomic_xchg(&multifd_send_state->exiting, 1)) {
+ return;
+ }
+
+ for (i = 0; i < migrate_multifd_channels(); i++) {
+ MultiFDSendParams *p = &multifd_send_state->params[i];
+
+ qemu_mutex_lock(&p->mutex);
+ p->quit = true;
+ qemu_sem_post(&p->sem);
+ qemu_mutex_unlock(&p->mutex);
+ }
+}
+
+void multifd_save_cleanup(void)
+{
+ int i;
+
+ if (!migrate_use_multifd()) {
+ return;
+ }
+ multifd_send_terminate_threads(NULL);
+ for (i = 0; i < migrate_multifd_channels(); i++) {
+ MultiFDSendParams *p = &multifd_send_state->params[i];
+
+ if (p->running) {
+ qemu_thread_join(&p->thread);
+ }
+ }
+ for (i = 0; i < migrate_multifd_channels(); i++) {
+ MultiFDSendParams *p = &multifd_send_state->params[i];
+
+ socket_send_channel_destroy(p->c);
+ 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);
+ p->pages = NULL;
+ p->packet_len = 0;
+ g_free(p->packet);
+ p->packet = NULL;
+ }
+ qemu_sem_destroy(&multifd_send_state->channels_ready);
+ g_free(multifd_send_state->params);
+ multifd_send_state->params = NULL;
+ multifd_pages_clear(multifd_send_state->pages);
+ multifd_send_state->pages = NULL;
+ g_free(multifd_send_state);
+ multifd_send_state = NULL;
+}
+
+void multifd_send_sync_main(QEMUFile *f)
+{
+ int i;
+
+ if (!migrate_use_multifd()) {
+ return;
+ }
+ if (multifd_send_state->pages->used) {
+ if (multifd_send_pages(f) < 0) {
+ error_report("%s: multifd_send_pages fail", __func__);
+ 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);
+
+ if (p->quit) {
+ error_report("%s: channel %d has already quit", __func__, i);
+ qemu_mutex_unlock(&p->mutex);
+ return;
+ }
+
+ p->packet_num = multifd_send_state->packet_num++;
+ p->flags |= MULTIFD_FLAG_SYNC;
+ p->pending_job++;
+ qemu_file_update_transfer(f, p->packet_len);
+ ram_counters.multifd_bytes += p->packet_len;
+ ram_counters.transferred += p->packet_len;
+ 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(&p->sem_sync);
+ }
+ trace_multifd_send_sync_main(multifd_send_state->packet_num);
+}
+
+static void *multifd_send_thread(void *opaque)
+{
+ MultiFDSendParams *p = opaque;
+ Error *local_err = NULL;
+ int ret = 0;
+ uint32_t flags = 0;
+
+ trace_multifd_send_thread_start(p->id);
+ rcu_register_thread();
+
+ if (multifd_send_initial_packet(p, &local_err) < 0) {
+ ret = -1;
+ goto out;
+ }
+ /* initial packet */
+ p->num_packets = 1;
+
+ while (true) {
+ qemu_sem_wait(&p->sem);
+
+ if (atomic_read(&multifd_send_state->exiting)) {
+ break;
+ }
+ qemu_mutex_lock(&p->mutex);
+
+ if (p->pending_job) {
+ uint32_t used = p->pages->used;
+ uint64_t packet_num = p->packet_num;
+ flags = p->flags;
+
+ p->next_packet_size = used * qemu_target_page_size();
+ multifd_send_fill_packet(p);
+ p->flags = 0;
+ p->num_packets++;
+ p->num_pages += used;
+ p->pages->used = 0;
+ p->pages->block = NULL;
+ qemu_mutex_unlock(&p->mutex);
+
+ trace_multifd_send(p->id, packet_num, used, flags,
+ p->next_packet_size);
+
+ ret = qio_channel_write_all(p->c, (void *)p->packet,
+ p->packet_len, &local_err);
+ if (ret != 0) {
+ break;
+ }
+
+ if (used) {
+ ret = qio_channel_writev_all(p->c, p->pages->iov,
+ used, &local_err);
+ if (ret != 0) {
+ break;
+ }
+ }
+
+ qemu_mutex_lock(&p->mutex);
+ p->pending_job--;
+ qemu_mutex_unlock(&p->mutex);
+
+ if (flags & MULTIFD_FLAG_SYNC) {
+ qemu_sem_post(&p->sem_sync);
+ }
+ qemu_sem_post(&multifd_send_state->channels_ready);
+ } else if (p->quit) {
+ qemu_mutex_unlock(&p->mutex);
+ break;
+ } else {
+ qemu_mutex_unlock(&p->mutex);
+ /* sometimes there are spurious wakeups */
+ }
+ }
+
+out:
+ if (local_err) {
+ trace_multifd_send_error(p->id);
+ multifd_send_terminate_threads(local_err);
+ }
+
+ /*
+ * Error happen, I will exit, but I can't just leave, tell
+ * who pay attention to me.
+ */
+ if (ret != 0) {
+ qemu_sem_post(&p->sem_sync);
+ qemu_sem_post(&multifd_send_state->channels_ready);
+ }
+
+ qemu_mutex_lock(&p->mutex);
+ p->running = false;
+ qemu_mutex_unlock(&p->mutex);
+
+ rcu_unregister_thread();
+ trace_multifd_send_thread_end(p->id, p->num_packets, p->num_pages);
+
+ return NULL;
+}
+
+static void multifd_new_send_channel_async(QIOTask *task, gpointer opaque)
+{
+ MultiFDSendParams *p = opaque;
+ QIOChannel *sioc = QIO_CHANNEL(qio_task_get_source(task));
+ Error *local_err = NULL;
+
+ trace_multifd_new_send_channel_async(p->id);
+ if (qio_task_propagate_error(task, &local_err)) {
+ migrate_set_error(migrate_get_current(), local_err);
+ /* Error happen, we need to tell who pay attention to me */
+ qemu_sem_post(&multifd_send_state->channels_ready);
+ qemu_sem_post(&p->sem_sync);
+ /*
+ * Although multifd_send_thread is not created, but main migration
+ * thread neet to judge whether it is running, so we need to mark
+ * its status.
+ */
+ p->quit = true;
+ } else {
+ p->c = QIO_CHANNEL(sioc);
+ qio_channel_set_delay(p->c, false);
+ p->running = true;
+ qemu_thread_create(&p->thread, p->name, multifd_send_thread, p,
+ QEMU_THREAD_JOINABLE);
+ }
+}
+
+int multifd_save_setup(Error **errp)
+{
+ int thread_count;
+ uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
+ uint8_t i;
+
+ if (!migrate_use_multifd()) {
+ return 0;
+ }
+ thread_count = migrate_multifd_channels();
+ multifd_send_state = g_malloc0(sizeof(*multifd_send_state));
+ multifd_send_state->params = g_new0(MultiFDSendParams, thread_count);
+ multifd_send_state->pages = multifd_pages_init(page_count);
+ qemu_sem_init(&multifd_send_state->channels_ready, 0);
+ atomic_set(&multifd_send_state->exiting, 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;
+ p->pages = multifd_pages_init(page_count);
+ p->packet_len = sizeof(MultiFDPacket_t)
+ + sizeof(uint64_t) * page_count;
+ p->packet = g_malloc0(p->packet_len);
+ p->packet->magic = cpu_to_be32(MULTIFD_MAGIC);
+ p->packet->version = cpu_to_be32(MULTIFD_VERSION);
+ p->name = g_strdup_printf("multifdsend_%d", i);
+ socket_send_channel_create(multifd_new_send_channel_async, p);
+ }
+ return 0;
+}
+
+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)
+{
+ int i;
+
+ trace_multifd_recv_terminate_threads(err != NULL);
+
+ if (err) {
+ MigrationState *s = migrate_get_current();
+ migrate_set_error(s, err);
+ if (s->state == MIGRATION_STATUS_SETUP ||
+ s->state == MIGRATION_STATUS_ACTIVE) {
+ migrate_set_state(&s->state, s->state,
+ MIGRATION_STATUS_FAILED);
+ }
+ }
+
+ for (i = 0; i < migrate_multifd_channels(); i++) {
+ MultiFDRecvParams *p = &multifd_recv_state->params[i];
+
+ qemu_mutex_lock(&p->mutex);
+ p->quit = true;
+ /*
+ * We could arrive here for two reasons:
+ * - normal quit, i.e. everything went fine, just finished
+ * - error quit: We close the channels so the channel threads
+ * finish the qio_channel_read_all_eof()
+ */
+ if (p->c) {
+ qio_channel_shutdown(p->c, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
+ }
+ qemu_mutex_unlock(&p->mutex);
+ }
+}
+
+int multifd_load_cleanup(Error **errp)
+{
+ int i;
+ int ret = 0;
+
+ if (!migrate_use_multifd()) {
+ return 0;
+ }
+ multifd_recv_terminate_threads(NULL);
+ for (i = 0; i < migrate_multifd_channels(); i++) {
+ MultiFDRecvParams *p = &multifd_recv_state->params[i];
+
+ if (p->running) {
+ p->quit = true;
+ /*
+ * multifd_recv_thread may hung at MULTIFD_FLAG_SYNC handle code,
+ * however try to wakeup it without harm in cleanup phase.
+ */
+ qemu_sem_post(&p->sem_sync);
+ qemu_thread_join(&p->thread);
+ }
+ }
+ for (i = 0; i < migrate_multifd_channels(); i++) {
+ MultiFDRecvParams *p = &multifd_recv_state->params[i];
+
+ object_unref(OBJECT(p->c));
+ p->c = NULL;
+ qemu_mutex_destroy(&p->mutex);
+ qemu_sem_destroy(&p->sem_sync);
+ g_free(p->name);
+ p->name = NULL;
+ multifd_pages_clear(p->pages);
+ p->pages = NULL;
+ p->packet_len = 0;
+ 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);
+ multifd_recv_state = NULL;
+
+ return ret;
+}
+
+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_wait(p->id);
+ qemu_sem_wait(&multifd_recv_state->sem_sync);
+ }
+ for (i = 0; i < migrate_multifd_channels(); i++) {
+ MultiFDRecvParams *p = &multifd_recv_state->params[i];
+
+ 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);
+ 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;
+ Error *local_err = NULL;
+ int ret;
+
+ trace_multifd_recv_thread_start(p->id);
+ rcu_register_thread();
+
+ while (true) {
+ uint32_t used;
+ uint32_t flags;
+
+ if (p->quit) {
+ break;
+ }
+
+ ret = qio_channel_read_all_eof(p->c, (void *)p->packet,
+ p->packet_len, &local_err);
+ if (ret == 0) { /* EOF */
+ break;
+ }
+ if (ret == -1) { /* Error */
+ break;
+ }
+
+ 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->next_packet_size);
+ p->num_packets++;
+ p->num_pages += used;
+ qemu_mutex_unlock(&p->mutex);
+
+ if (used) {
+ ret = qio_channel_readv_all(p->c, p->pages->iov,
+ used, &local_err);
+ if (ret != 0) {
+ break;
+ }
+ }
+
+ if (flags & MULTIFD_FLAG_SYNC) {
+ qemu_sem_post(&multifd_recv_state->sem_sync);
+ qemu_sem_wait(&p->sem_sync);
+ }
+ }
+
+ if (local_err) {
+ multifd_recv_terminate_threads(local_err);
+ }
+ qemu_mutex_lock(&p->mutex);
+ p->running = false;
+ qemu_mutex_unlock(&p->mutex);
+
+ rcu_unregister_thread();
+ trace_multifd_recv_thread_end(p->id, p->num_packets, p->num_pages);
+
+ return NULL;
+}
+
+int multifd_load_setup(Error **errp)
+{
+ int thread_count;
+ uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
+ uint8_t i;
+
+ if (!migrate_use_multifd()) {
+ return 0;
+ }
+ thread_count = migrate_multifd_channels();
+ 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_sync, 0);
+ p->quit = false;
+ p->id = i;
+ p->pages = multifd_pages_init(page_count);
+ p->packet_len = sizeof(MultiFDPacket_t)
+ + sizeof(uint64_t) * page_count;
+ p->packet = g_malloc0(p->packet_len);
+ p->name = g_strdup_printf("multifdrecv_%d", i);
+ }
+ return 0;
+}
+
+bool multifd_recv_all_channels_created(void)
+{
+ int thread_count = migrate_multifd_channels();
+
+ if (!migrate_use_multifd()) {
+ return true;
+ }
+
+ return thread_count == atomic_read(&multifd_recv_state->count);
+}
+
+/*
+ * Try to receive all multifd channels to get ready for the migration.
+ * - Return true and do not set @errp when correctly receving all channels;
+ * - Return false and do not set @errp when correctly receiving the current one;
+ * - Return false and set @errp when failing to receive the current channel.
+ */
+bool multifd_recv_new_channel(QIOChannel *ioc, Error **errp)
+{
+ MultiFDRecvParams *p;
+ Error *local_err = NULL;
+ int id;
+
+ id = multifd_recv_initial_packet(ioc, &local_err);
+ if (id < 0) {
+ multifd_recv_terminate_threads(local_err);
+ error_propagate_prepend(errp, local_err,
+ "failed to receive packet"
+ " via multifd channel %d: ",
+ atomic_read(&multifd_recv_state->count));
+ return false;
+ }
+ trace_multifd_recv_new_channel(id);
+
+ p = &multifd_recv_state->params[id];
+ if (p->c != NULL) {
+ error_setg(&local_err, "multifd: received id '%d' already setup'",
+ id);
+ multifd_recv_terminate_threads(local_err);
+ error_propagate(errp, local_err);
+ return false;
+ }
+ p->c = ioc;
+ object_ref(OBJECT(ioc));
+ /* initial packet */
+ p->num_packets = 1;
+
+ p->running = true;
+ qemu_thread_create(&p->thread, p->name, multifd_recv_thread, p,
+ QEMU_THREAD_JOINABLE);
+ atomic_inc(&multifd_recv_state->count);
+ return atomic_read(&multifd_recv_state->count) ==
+ migrate_multifd_channels();
+}
+
new file mode 100644
@@ -0,0 +1,139 @@
+/*
+ * Multifd common functions
+ *
+ * Copyright (c) 2019-2020 Red Hat Inc
+ *
+ * Authors:
+ * Juan Quintela <quintela@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef QEMU_MIGRATION_MULTIFD_H
+#define QEMU_MIGRATION_MULTIFD_H
+
+int multifd_save_setup(Error **errp);
+void multifd_save_cleanup(void);
+int multifd_load_setup(Error **errp);
+int multifd_load_cleanup(Error **errp);
+bool multifd_recv_all_channels_created(void);
+bool multifd_recv_new_channel(QIOChannel *ioc, Error **errp);
+void multifd_recv_sync_main(void);
+void multifd_send_sync_main(QEMUFile *f);
+int multifd_queue_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset);
+
+#define MULTIFD_FLAG_SYNC (1 << 0)
+
+/* This value needs to be a multiple of qemu_target_page_size() */
+#define MULTIFD_PACKET_SIZE (512 * 1024)
+
+typedef struct {
+ uint32_t magic;
+ uint32_t version;
+ uint32_t flags;
+ /* maximum number of allocated pages */
+ uint32_t pages_alloc;
+ uint32_t pages_used;
+ /* size of the next packet that contains pages */
+ uint32_t next_packet_size;
+ uint64_t packet_num;
+ uint64_t unused[4]; /* Reserved for future use */
+ char ramblock[256];
+ uint64_t offset[];
+} __attribute__((packed)) MultiFDPacket_t;
+
+typedef struct {
+ /* number of used pages */
+ uint32_t used;
+ /* number of allocated pages */
+ uint32_t allocated;
+ /* global number of generated multifd packets */
+ uint64_t packet_num;
+ /* offset of each page */
+ ram_addr_t *offset;
+ /* pointer to each page */
+ struct iovec *iov;
+ RAMBlock *block;
+} MultiFDPages_t;
+
+typedef struct {
+ /* this fields are not changed once the thread is created */
+ /* channel number */
+ uint8_t id;
+ /* channel thread name */
+ char *name;
+ /* channel thread id */
+ QemuThread thread;
+ /* communication channel */
+ QIOChannel *c;
+ /* sem where to wait for more work */
+ QemuSemaphore sem;
+ /* this mutex protects the following parameters */
+ QemuMutex mutex;
+ /* is this channel thread running */
+ bool running;
+ /* should this thread finish */
+ bool quit;
+ /* thread has work to do */
+ int pending_job;
+ /* array of pages to sent */
+ MultiFDPages_t *pages;
+ /* packet allocated len */
+ uint32_t packet_len;
+ /* pointer to the packet */
+ MultiFDPacket_t *packet;
+ /* multifd flags for each packet */
+ uint32_t flags;
+ /* size of the next packet that contains pages */
+ uint32_t next_packet_size;
+ /* global number of generated multifd packets */
+ uint64_t packet_num;
+ /* thread local variables */
+ /* packets sent through this channel */
+ uint64_t num_packets;
+ /* pages sent through this channel */
+ uint64_t num_pages;
+ /* syncs main thread and channels */
+ QemuSemaphore sem_sync;
+} MultiFDSendParams;
+
+typedef struct {
+ /* this fields are not changed once the thread is created */
+ /* channel number */
+ uint8_t id;
+ /* channel thread name */
+ char *name;
+ /* channel thread id */
+ QemuThread thread;
+ /* communication channel */
+ QIOChannel *c;
+ /* this mutex protects the following parameters */
+ QemuMutex mutex;
+ /* is this channel thread running */
+ bool running;
+ /* should this thread finish */
+ bool quit;
+ /* array of pages to receive */
+ MultiFDPages_t *pages;
+ /* packet allocated len */
+ uint32_t packet_len;
+ /* pointer to the packet */
+ MultiFDPacket_t *packet;
+ /* multifd flags for each packet */
+ uint32_t flags;
+ /* global number of generated multifd packets */
+ uint64_t packet_num;
+ /* thread local variables */
+ /* size of the next packet that contains pages */
+ uint32_t next_packet_size;
+ /* packets sent through this channel */
+ uint64_t num_packets;
+ /* pages sent through this channel */
+ uint64_t num_pages;
+ /* syncs main thread and channels */
+ QemuSemaphore sem_sync;
+} MultiFDRecvParams;
+
+#endif
+
@@ -36,7 +36,6 @@
#include "xbzrle.h"
#include "ram.h"
#include "migration.h"
-#include "socket.h"
#include "migration/register.h"
#include "migration/misc.h"
#include "qemu-file.h"
@@ -53,9 +52,9 @@
#include "migration/colo.h"
#include "block.h"
#include "sysemu/sysemu.h"
-#include "qemu/uuid.h"
#include "savevm.h"
#include "qemu/iov.h"
+#include "multifd.h"
/***********************************************************/
/* ram save/restore */
@@ -575,991 +574,6 @@ exit:
return -1;
}
-/* Multiple fd's */
-
-#define MULTIFD_MAGIC 0x11223344U
-#define MULTIFD_VERSION 1
-
-#define MULTIFD_FLAG_SYNC (1 << 0)
-
-/* This value needs to be a multiple of qemu_target_page_size() */
-#define MULTIFD_PACKET_SIZE (512 * 1024)
-
-typedef struct {
- uint32_t magic;
- uint32_t version;
- unsigned char uuid[16]; /* QemuUUID */
- uint8_t id;
- uint8_t unused1[7]; /* Reserved for future use */
- uint64_t unused2[4]; /* Reserved for future use */
-} __attribute__((packed)) MultiFDInit_t;
-
-typedef struct {
- uint32_t magic;
- uint32_t version;
- uint32_t flags;
- /* maximum number of allocated pages */
- uint32_t pages_alloc;
- uint32_t pages_used;
- /* size of the next packet that contains pages */
- uint32_t next_packet_size;
- uint64_t packet_num;
- uint64_t unused[4]; /* Reserved for future use */
- char ramblock[256];
- uint64_t offset[];
-} __attribute__((packed)) MultiFDPacket_t;
-
-typedef struct {
- /* number of used pages */
- uint32_t used;
- /* number of allocated pages */
- uint32_t allocated;
- /* global number of generated multifd packets */
- uint64_t packet_num;
- /* offset of each page */
- ram_addr_t *offset;
- /* pointer to each page */
- struct iovec *iov;
- RAMBlock *block;
-} MultiFDPages_t;
-
-typedef struct {
- /* this fields are not changed once the thread is created */
- /* channel number */
- uint8_t id;
- /* channel thread name */
- char *name;
- /* channel thread id */
- QemuThread thread;
- /* communication channel */
- QIOChannel *c;
- /* sem where to wait for more work */
- QemuSemaphore sem;
- /* this mutex protects the following parameters */
- QemuMutex mutex;
- /* is this channel thread running */
- bool running;
- /* should this thread finish */
- bool quit;
- /* thread has work to do */
- int pending_job;
- /* array of pages to sent */
- MultiFDPages_t *pages;
- /* packet allocated len */
- uint32_t packet_len;
- /* pointer to the packet */
- MultiFDPacket_t *packet;
- /* multifd flags for each packet */
- uint32_t flags;
- /* size of the next packet that contains pages */
- uint32_t next_packet_size;
- /* global number of generated multifd packets */
- uint64_t packet_num;
- /* thread local variables */
- /* packets sent through this channel */
- uint64_t num_packets;
- /* pages sent through this channel */
- uint64_t num_pages;
- /* syncs main thread and channels */
- QemuSemaphore sem_sync;
-} MultiFDSendParams;
-
-typedef struct {
- /* this fields are not changed once the thread is created */
- /* channel number */
- uint8_t id;
- /* channel thread name */
- char *name;
- /* channel thread id */
- QemuThread thread;
- /* communication channel */
- QIOChannel *c;
- /* this mutex protects the following parameters */
- QemuMutex mutex;
- /* is this channel thread running */
- bool running;
- /* should this thread finish */
- bool quit;
- /* array of pages to receive */
- MultiFDPages_t *pages;
- /* packet allocated len */
- uint32_t packet_len;
- /* pointer to the packet */
- MultiFDPacket_t *packet;
- /* multifd flags for each packet */
- uint32_t flags;
- /* global number of generated multifd packets */
- uint64_t packet_num;
- /* thread local variables */
- /* size of the next packet that contains pages */
- uint32_t next_packet_size;
- /* packets sent through this channel */
- 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)
-{
- MultiFDInit_t msg = {};
- int ret;
-
- msg.magic = cpu_to_be32(MULTIFD_MAGIC);
- msg.version = cpu_to_be32(MULTIFD_VERSION);
- msg.id = p->id;
- memcpy(msg.uuid, &qemu_uuid.data, sizeof(msg.uuid));
-
- ret = qio_channel_write_all(p->c, (char *)&msg, sizeof(msg), errp);
- if (ret != 0) {
- return -1;
- }
- return 0;
-}
-
-static int multifd_recv_initial_packet(QIOChannel *c, Error **errp)
-{
- MultiFDInit_t msg;
- int ret;
-
- ret = qio_channel_read_all(c, (char *)&msg, sizeof(msg), errp);
- if (ret != 0) {
- return -1;
- }
-
- msg.magic = be32_to_cpu(msg.magic);
- msg.version = be32_to_cpu(msg.version);
-
- if (msg.magic != MULTIFD_MAGIC) {
- error_setg(errp, "multifd: received packet magic %x "
- "expected %x", msg.magic, MULTIFD_MAGIC);
- return -1;
- }
-
- if (msg.version != MULTIFD_VERSION) {
- error_setg(errp, "multifd: received packet version %d "
- "expected %d", msg.version, MULTIFD_VERSION);
- return -1;
- }
-
- if (memcmp(msg.uuid, &qemu_uuid, sizeof(qemu_uuid))) {
- char *uuid = qemu_uuid_unparse_strdup(&qemu_uuid);
- char *msg_uuid = qemu_uuid_unparse_strdup((const QemuUUID *)msg.uuid);
-
- error_setg(errp, "multifd: received uuid '%s' and expected "
- "uuid '%s' for channel %hhd", msg_uuid, uuid, msg.id);
- g_free(uuid);
- g_free(msg_uuid);
- return -1;
- }
-
- if (msg.id > migrate_multifd_channels()) {
- error_setg(errp, "multifd: received channel version %d "
- "expected %d", msg.version, MULTIFD_VERSION);
- return -1;
- }
-
- return msg.id;
-}
-
-static MultiFDPages_t *multifd_pages_init(size_t size)
-{
- MultiFDPages_t *pages = g_new0(MultiFDPages_t, 1);
-
- pages->allocated = size;
- pages->iov = g_new0(struct iovec, size);
- pages->offset = g_new0(ram_addr_t, size);
-
- return pages;
-}
-
-static void multifd_pages_clear(MultiFDPages_t *pages)
-{
- pages->used = 0;
- pages->allocated = 0;
- pages->packet_num = 0;
- pages->block = NULL;
- g_free(pages->iov);
- pages->iov = NULL;
- g_free(pages->offset);
- pages->offset = NULL;
- g_free(pages);
-}
-
-static void multifd_send_fill_packet(MultiFDSendParams *p)
-{
- MultiFDPacket_t *packet = p->packet;
- int i;
-
- packet->flags = cpu_to_be32(p->flags);
- packet->pages_alloc = cpu_to_be32(p->pages->allocated);
- packet->pages_used = cpu_to_be32(p->pages->used);
- packet->next_packet_size = cpu_to_be32(p->next_packet_size);
- packet->packet_num = cpu_to_be64(p->packet_num);
-
- if (p->pages->block) {
- strncpy(packet->ramblock, p->pages->block->idstr, 256);
- }
-
- for (i = 0; i < p->pages->used; i++) {
- /* there are architectures where ram_addr_t is 32 bit */
- uint64_t temp = p->pages->offset[i];
-
- packet->offset[i] = cpu_to_be64(temp);
- }
-}
-
-static int multifd_recv_unfill_packet(MultiFDRecvParams *p, Error **errp)
-{
- MultiFDPacket_t *packet = p->packet;
- uint32_t pages_max = MULTIFD_PACKET_SIZE / qemu_target_page_size();
- RAMBlock *block;
- int i;
-
- packet->magic = be32_to_cpu(packet->magic);
- if (packet->magic != MULTIFD_MAGIC) {
- error_setg(errp, "multifd: received packet "
- "magic %x and expected magic %x",
- packet->magic, MULTIFD_MAGIC);
- return -1;
- }
-
- packet->version = be32_to_cpu(packet->version);
- if (packet->version != MULTIFD_VERSION) {
- error_setg(errp, "multifd: received packet "
- "version %d and expected version %d",
- packet->version, MULTIFD_VERSION);
- return -1;
- }
-
- p->flags = be32_to_cpu(packet->flags);
-
- packet->pages_alloc = be32_to_cpu(packet->pages_alloc);
- /*
- * If we received a packet that is 100 times bigger than expected
- * just stop migration. It is a magic number.
- */
- if (packet->pages_alloc > pages_max * 100) {
- error_setg(errp, "multifd: received packet "
- "with size %d and expected a maximum size of %d",
- packet->pages_alloc, pages_max * 100) ;
- return -1;
- }
- /*
- * We received a packet that is bigger than expected but inside
- * reasonable limits (see previous comment). Just reallocate.
- */
- if (packet->pages_alloc > p->pages->allocated) {
- multifd_pages_clear(p->pages);
- p->pages = multifd_pages_init(packet->pages_alloc);
- }
-
- p->pages->used = be32_to_cpu(packet->pages_used);
- if (p->pages->used > packet->pages_alloc) {
- error_setg(errp, "multifd: received packet "
- "with %d pages and expected maximum pages are %d",
- p->pages->used, packet->pages_alloc) ;
- return -1;
- }
-
- p->next_packet_size = be32_to_cpu(packet->next_packet_size);
- p->packet_num = be64_to_cpu(packet->packet_num);
-
- if (p->pages->used == 0) {
- return 0;
- }
-
- /* make sure that ramblock is 0 terminated */
- packet->ramblock[255] = 0;
- block = qemu_ram_block_by_name(packet->ramblock);
- if (!block) {
- error_setg(errp, "multifd: unknown ram block %s",
- packet->ramblock);
- return -1;
- }
-
- for (i = 0; i < p->pages->used; i++) {
- uint64_t offset = be64_to_cpu(packet->offset[i]);
-
- if (offset > (block->used_length - qemu_target_page_size())) {
- error_setg(errp, "multifd: offset too long %" PRIu64
- " (max " RAM_ADDR_FMT ")",
- offset, block->max_length);
- return -1;
- }
- p->pages->iov[i].iov_base = block->host + offset;
- p->pages->iov[i].iov_len = qemu_target_page_size();
- }
-
- return 0;
-}
-
-struct {
- MultiFDSendParams *params;
- /* array of pages to sent */
- MultiFDPages_t *pages;
- /* global number of generated multifd packets */
- uint64_t packet_num;
- /* send channels ready */
- QemuSemaphore channels_ready;
- /*
- * Have we already run terminate threads. There is a race when it
- * happens that we got one error while we are exiting.
- * We will use atomic operations. Only valid values are 0 and 1.
- */
- int exiting;
-} *multifd_send_state;
-
-/*
- * How we use multifd_send_state->pages and channel->pages?
- *
- * We create a pages for each channel, and a main one. Each time that
- * we need to send a batch of pages we interchange the ones between
- * multifd_send_state and the channel that is sending it. There are
- * two reasons for that:
- * - to not have to do so many mallocs during migration
- * - to make easier to know what to free at the end of migration
- *
- * This way we always know who is the owner of each "pages" struct,
- * and we don't need any locking. It belongs to the migration thread
- * or to the channel thread. Switching is safe because the migration
- * thread is using the channel mutex when changing it, and the channel
- * have to had finish with its own, otherwise pending_job can't be
- * false.
- */
-
-static int multifd_send_pages(QEMUFile *f)
-{
- int i;
- static int next_channel;
- MultiFDSendParams *p = NULL; /* make happy gcc */
- MultiFDPages_t *pages = multifd_send_state->pages;
- uint64_t transferred;
-
- if (atomic_read(&multifd_send_state->exiting)) {
- return -1;
- }
-
- qemu_sem_wait(&multifd_send_state->channels_ready);
- for (i = next_channel;; i = (i + 1) % migrate_multifd_channels()) {
- p = &multifd_send_state->params[i];
-
- qemu_mutex_lock(&p->mutex);
- if (p->quit) {
- error_report("%s: channel %d has already quit!", __func__, i);
- qemu_mutex_unlock(&p->mutex);
- return -1;
- }
- if (!p->pending_job) {
- p->pending_job++;
- next_channel = (i + 1) % migrate_multifd_channels();
- break;
- }
- qemu_mutex_unlock(&p->mutex);
- }
- assert(!p->pages->used);
- assert(!p->pages->block);
-
- p->packet_num = multifd_send_state->packet_num++;
- multifd_send_state->pages = p->pages;
- p->pages = pages;
- transferred = ((uint64_t) pages->used) * qemu_target_page_size()
- + p->packet_len;
- qemu_file_update_transfer(f, transferred);
- ram_counters.multifd_bytes += transferred;
- ram_counters.transferred += transferred;;
- qemu_mutex_unlock(&p->mutex);
- qemu_sem_post(&p->sem);
-
- return 1;
-}
-
-static int multifd_queue_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset)
-{
- MultiFDPages_t *pages = multifd_send_state->pages;
-
- if (!pages->block) {
- pages->block = block;
- }
-
- if (pages->block == block) {
- pages->offset[pages->used] = offset;
- pages->iov[pages->used].iov_base = block->host + offset;
- pages->iov[pages->used].iov_len = qemu_target_page_size();
- pages->used++;
-
- if (pages->used < pages->allocated) {
- return 1;
- }
- }
-
- if (multifd_send_pages(f) < 0) {
- return -1;
- }
-
- if (pages->block != block) {
- return multifd_queue_page(f, block, offset);
- }
-
- return 1;
-}
-
-static void multifd_send_terminate_threads(Error *err)
-{
- int i;
-
- trace_multifd_send_terminate_threads(err != NULL);
-
- if (err) {
- MigrationState *s = migrate_get_current();
- migrate_set_error(s, err);
- if (s->state == MIGRATION_STATUS_SETUP ||
- s->state == MIGRATION_STATUS_PRE_SWITCHOVER ||
- s->state == MIGRATION_STATUS_DEVICE ||
- s->state == MIGRATION_STATUS_ACTIVE) {
- migrate_set_state(&s->state, s->state,
- MIGRATION_STATUS_FAILED);
- }
- }
-
- /*
- * We don't want to exit each threads twice. Depending on where
- * we get the error, or if there are two independent errors in two
- * threads at the same time, we can end calling this function
- * twice.
- */
- if (atomic_xchg(&multifd_send_state->exiting, 1)) {
- return;
- }
-
- for (i = 0; i < migrate_multifd_channels(); i++) {
- MultiFDSendParams *p = &multifd_send_state->params[i];
-
- qemu_mutex_lock(&p->mutex);
- p->quit = true;
- qemu_sem_post(&p->sem);
- qemu_mutex_unlock(&p->mutex);
- }
-}
-
-void multifd_save_cleanup(void)
-{
- int i;
-
- if (!migrate_use_multifd()) {
- return;
- }
- multifd_send_terminate_threads(NULL);
- for (i = 0; i < migrate_multifd_channels(); i++) {
- MultiFDSendParams *p = &multifd_send_state->params[i];
-
- if (p->running) {
- qemu_thread_join(&p->thread);
- }
- }
- for (i = 0; i < migrate_multifd_channels(); i++) {
- MultiFDSendParams *p = &multifd_send_state->params[i];
-
- socket_send_channel_destroy(p->c);
- 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);
- p->pages = NULL;
- p->packet_len = 0;
- g_free(p->packet);
- p->packet = NULL;
- }
- qemu_sem_destroy(&multifd_send_state->channels_ready);
- g_free(multifd_send_state->params);
- multifd_send_state->params = NULL;
- multifd_pages_clear(multifd_send_state->pages);
- multifd_send_state->pages = NULL;
- g_free(multifd_send_state);
- multifd_send_state = NULL;
-}
-
-static void multifd_send_sync_main(QEMUFile *f)
-{
- int i;
-
- if (!migrate_use_multifd()) {
- return;
- }
- if (multifd_send_state->pages->used) {
- if (multifd_send_pages(f) < 0) {
- error_report("%s: multifd_send_pages fail", __func__);
- 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);
-
- if (p->quit) {
- error_report("%s: channel %d has already quit", __func__, i);
- qemu_mutex_unlock(&p->mutex);
- return;
- }
-
- p->packet_num = multifd_send_state->packet_num++;
- p->flags |= MULTIFD_FLAG_SYNC;
- p->pending_job++;
- qemu_file_update_transfer(f, p->packet_len);
- ram_counters.multifd_bytes += p->packet_len;
- ram_counters.transferred += p->packet_len;
- 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(&p->sem_sync);
- }
- trace_multifd_send_sync_main(multifd_send_state->packet_num);
-}
-
-static void *multifd_send_thread(void *opaque)
-{
- MultiFDSendParams *p = opaque;
- Error *local_err = NULL;
- int ret = 0;
- uint32_t flags = 0;
-
- trace_multifd_send_thread_start(p->id);
- rcu_register_thread();
-
- if (multifd_send_initial_packet(p, &local_err) < 0) {
- ret = -1;
- goto out;
- }
- /* initial packet */
- p->num_packets = 1;
-
- while (true) {
- qemu_sem_wait(&p->sem);
-
- if (atomic_read(&multifd_send_state->exiting)) {
- break;
- }
- qemu_mutex_lock(&p->mutex);
-
- if (p->pending_job) {
- uint32_t used = p->pages->used;
- uint64_t packet_num = p->packet_num;
- flags = p->flags;
-
- p->next_packet_size = used * qemu_target_page_size();
- multifd_send_fill_packet(p);
- p->flags = 0;
- p->num_packets++;
- p->num_pages += used;
- p->pages->used = 0;
- p->pages->block = NULL;
- qemu_mutex_unlock(&p->mutex);
-
- trace_multifd_send(p->id, packet_num, used, flags,
- p->next_packet_size);
-
- ret = qio_channel_write_all(p->c, (void *)p->packet,
- p->packet_len, &local_err);
- if (ret != 0) {
- break;
- }
-
- if (used) {
- ret = qio_channel_writev_all(p->c, p->pages->iov,
- used, &local_err);
- if (ret != 0) {
- break;
- }
- }
-
- qemu_mutex_lock(&p->mutex);
- p->pending_job--;
- qemu_mutex_unlock(&p->mutex);
-
- if (flags & MULTIFD_FLAG_SYNC) {
- qemu_sem_post(&p->sem_sync);
- }
- qemu_sem_post(&multifd_send_state->channels_ready);
- } else if (p->quit) {
- qemu_mutex_unlock(&p->mutex);
- break;
- } else {
- qemu_mutex_unlock(&p->mutex);
- /* sometimes there are spurious wakeups */
- }
- }
-
-out:
- if (local_err) {
- trace_multifd_send_error(p->id);
- multifd_send_terminate_threads(local_err);
- }
-
- /*
- * Error happen, I will exit, but I can't just leave, tell
- * who pay attention to me.
- */
- if (ret != 0) {
- qemu_sem_post(&p->sem_sync);
- qemu_sem_post(&multifd_send_state->channels_ready);
- }
-
- qemu_mutex_lock(&p->mutex);
- p->running = false;
- qemu_mutex_unlock(&p->mutex);
-
- rcu_unregister_thread();
- trace_multifd_send_thread_end(p->id, p->num_packets, p->num_pages);
-
- return NULL;
-}
-
-static void multifd_new_send_channel_async(QIOTask *task, gpointer opaque)
-{
- MultiFDSendParams *p = opaque;
- QIOChannel *sioc = QIO_CHANNEL(qio_task_get_source(task));
- Error *local_err = NULL;
-
- trace_multifd_new_send_channel_async(p->id);
- if (qio_task_propagate_error(task, &local_err)) {
- migrate_set_error(migrate_get_current(), local_err);
- /* Error happen, we need to tell who pay attention to me */
- qemu_sem_post(&multifd_send_state->channels_ready);
- qemu_sem_post(&p->sem_sync);
- /*
- * Although multifd_send_thread is not created, but main migration
- * thread neet to judge whether it is running, so we need to mark
- * its status.
- */
- p->quit = true;
- } else {
- p->c = QIO_CHANNEL(sioc);
- qio_channel_set_delay(p->c, false);
- p->running = true;
- qemu_thread_create(&p->thread, p->name, multifd_send_thread, p,
- QEMU_THREAD_JOINABLE);
- }
-}
-
-int multifd_save_setup(Error **errp)
-{
- int thread_count;
- uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
- uint8_t i;
-
- if (!migrate_use_multifd()) {
- return 0;
- }
- thread_count = migrate_multifd_channels();
- multifd_send_state = g_malloc0(sizeof(*multifd_send_state));
- multifd_send_state->params = g_new0(MultiFDSendParams, thread_count);
- multifd_send_state->pages = multifd_pages_init(page_count);
- qemu_sem_init(&multifd_send_state->channels_ready, 0);
- atomic_set(&multifd_send_state->exiting, 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;
- p->pages = multifd_pages_init(page_count);
- p->packet_len = sizeof(MultiFDPacket_t)
- + sizeof(uint64_t) * page_count;
- p->packet = g_malloc0(p->packet_len);
- p->packet->magic = cpu_to_be32(MULTIFD_MAGIC);
- p->packet->version = cpu_to_be32(MULTIFD_VERSION);
- p->name = g_strdup_printf("multifdsend_%d", i);
- socket_send_channel_create(multifd_new_send_channel_async, p);
- }
- return 0;
-}
-
-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)
-{
- int i;
-
- trace_multifd_recv_terminate_threads(err != NULL);
-
- if (err) {
- MigrationState *s = migrate_get_current();
- migrate_set_error(s, err);
- if (s->state == MIGRATION_STATUS_SETUP ||
- s->state == MIGRATION_STATUS_ACTIVE) {
- migrate_set_state(&s->state, s->state,
- MIGRATION_STATUS_FAILED);
- }
- }
-
- for (i = 0; i < migrate_multifd_channels(); i++) {
- MultiFDRecvParams *p = &multifd_recv_state->params[i];
-
- qemu_mutex_lock(&p->mutex);
- p->quit = true;
- /*
- * We could arrive here for two reasons:
- * - normal quit, i.e. everything went fine, just finished
- * - error quit: We close the channels so the channel threads
- * finish the qio_channel_read_all_eof()
- */
- if (p->c) {
- qio_channel_shutdown(p->c, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
- }
- qemu_mutex_unlock(&p->mutex);
- }
-}
-
-int multifd_load_cleanup(Error **errp)
-{
- int i;
- int ret = 0;
-
- if (!migrate_use_multifd()) {
- return 0;
- }
- multifd_recv_terminate_threads(NULL);
- for (i = 0; i < migrate_multifd_channels(); i++) {
- MultiFDRecvParams *p = &multifd_recv_state->params[i];
-
- if (p->running) {
- p->quit = true;
- /*
- * multifd_recv_thread may hung at MULTIFD_FLAG_SYNC handle code,
- * however try to wakeup it without harm in cleanup phase.
- */
- qemu_sem_post(&p->sem_sync);
- qemu_thread_join(&p->thread);
- }
- }
- for (i = 0; i < migrate_multifd_channels(); i++) {
- MultiFDRecvParams *p = &multifd_recv_state->params[i];
-
- object_unref(OBJECT(p->c));
- p->c = NULL;
- qemu_mutex_destroy(&p->mutex);
- qemu_sem_destroy(&p->sem_sync);
- g_free(p->name);
- p->name = NULL;
- multifd_pages_clear(p->pages);
- p->pages = NULL;
- p->packet_len = 0;
- 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);
- multifd_recv_state = NULL;
-
- 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_wait(p->id);
- qemu_sem_wait(&multifd_recv_state->sem_sync);
- }
- for (i = 0; i < migrate_multifd_channels(); i++) {
- MultiFDRecvParams *p = &multifd_recv_state->params[i];
-
- 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);
- 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;
- Error *local_err = NULL;
- int ret;
-
- trace_multifd_recv_thread_start(p->id);
- rcu_register_thread();
-
- while (true) {
- uint32_t used;
- uint32_t flags;
-
- if (p->quit) {
- break;
- }
-
- ret = qio_channel_read_all_eof(p->c, (void *)p->packet,
- p->packet_len, &local_err);
- if (ret == 0) { /* EOF */
- break;
- }
- if (ret == -1) { /* Error */
- break;
- }
-
- 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->next_packet_size);
- p->num_packets++;
- p->num_pages += used;
- qemu_mutex_unlock(&p->mutex);
-
- if (used) {
- ret = qio_channel_readv_all(p->c, p->pages->iov,
- used, &local_err);
- if (ret != 0) {
- break;
- }
- }
-
- if (flags & MULTIFD_FLAG_SYNC) {
- qemu_sem_post(&multifd_recv_state->sem_sync);
- qemu_sem_wait(&p->sem_sync);
- }
- }
-
- if (local_err) {
- multifd_recv_terminate_threads(local_err);
- }
- qemu_mutex_lock(&p->mutex);
- p->running = false;
- qemu_mutex_unlock(&p->mutex);
-
- rcu_unregister_thread();
- trace_multifd_recv_thread_end(p->id, p->num_packets, p->num_pages);
-
- return NULL;
-}
-
-int multifd_load_setup(Error **errp)
-{
- int thread_count;
- uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
- uint8_t i;
-
- if (!migrate_use_multifd()) {
- return 0;
- }
- thread_count = migrate_multifd_channels();
- 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_sync, 0);
- p->quit = false;
- p->id = i;
- p->pages = multifd_pages_init(page_count);
- p->packet_len = sizeof(MultiFDPacket_t)
- + sizeof(uint64_t) * page_count;
- p->packet = g_malloc0(p->packet_len);
- p->name = g_strdup_printf("multifdrecv_%d", i);
- }
- return 0;
-}
-
-bool multifd_recv_all_channels_created(void)
-{
- int thread_count = migrate_multifd_channels();
-
- if (!migrate_use_multifd()) {
- return true;
- }
-
- return thread_count == atomic_read(&multifd_recv_state->count);
-}
-
-/*
- * Try to receive all multifd channels to get ready for the migration.
- * - Return true and do not set @errp when correctly receving all channels;
- * - Return false and do not set @errp when correctly receiving the current one;
- * - Return false and set @errp when failing to receive the current channel.
- */
-bool multifd_recv_new_channel(QIOChannel *ioc, Error **errp)
-{
- MultiFDRecvParams *p;
- Error *local_err = NULL;
- int id;
-
- id = multifd_recv_initial_packet(ioc, &local_err);
- if (id < 0) {
- multifd_recv_terminate_threads(local_err);
- error_propagate_prepend(errp, local_err,
- "failed to receive packet"
- " via multifd channel %d: ",
- atomic_read(&multifd_recv_state->count));
- return false;
- }
- trace_multifd_recv_new_channel(id);
-
- p = &multifd_recv_state->params[id];
- if (p->c != NULL) {
- error_setg(&local_err, "multifd: received id '%d' already setup'",
- id);
- multifd_recv_terminate_threads(local_err);
- error_propagate(errp, local_err);
- return false;
- }
- p->c = ioc;
- object_ref(OBJECT(ioc));
- /* initial packet */
- p->num_packets = 1;
-
- p->running = true;
- qemu_thread_create(&p->thread, p->name, multifd_recv_thread, p,
- QEMU_THREAD_JOINABLE);
- atomic_inc(&multifd_recv_state->count);
- return atomic_read(&multifd_recv_state->count) ==
- migrate_multifd_channels();
-}
-
/**
* save_page_header: write page header to wire
*
@@ -41,13 +41,6 @@ int xbzrle_cache_resize(int64_t new_size, Error **errp);
uint64_t ram_bytes_remaining(void);
uint64_t ram_bytes_total(void);
-int multifd_save_setup(Error **errp);
-void multifd_save_cleanup(void);
-int multifd_load_setup(Error **errp);
-int multifd_load_cleanup(Error **errp);
-bool multifd_recv_all_channels_created(void);
-bool multifd_recv_new_channel(QIOChannel *ioc, Error **errp);
-
uint64_t ram_pagesize_summary(void);
int ram_save_queue_pages(const char *rbname, ram_addr_t start, ram_addr_t len);
void acct_update_position(QEMUFile *f, size_t size, bool zero);