X-Git-Url: https://repo.jachan.dev/qemu.git/blobdiff_plain/25242635acb0b803392ad5669b5624815af3fd07..a3416197447e7846a927b6ccb4f1edb3a1982443:/migration.c

diff --git a/migration.c b/migration.c
index 5513dde18d..058f9e69f4 100644
--- a/migration.c
+++ b/migration.c
@@ -23,6 +23,7 @@
 #include "migration/block.h"
 #include "qemu/thread.h"
 #include "qmp-commands.h"
+#include "trace.h"
 
 //#define DEBUG_MIGRATION
 
@@ -85,7 +86,7 @@ void qemu_start_incoming_migration(const char *uri, Error **errp)
         fd_start_incoming_migration(p, errp);
 #endif
     else {
-        error_setg(errp, "unknown migration protocol: %s\n", uri);
+        error_setg(errp, "unknown migration protocol: %s", uri);
     }
 }
 
@@ -95,11 +96,10 @@ static void process_incoming_migration_co(void *opaque)
     int ret;
 
     ret = qemu_loadvm_state(f);
-    qemu_set_fd_handler(qemu_get_fd(f), NULL, NULL, NULL);
     qemu_fclose(f);
     if (ret < 0) {
         fprintf(stderr, "load of migration failed\n");
-        exit(0);
+        exit(EXIT_FAILURE);
     }
     qemu_announce_self();
     DPRINTF("successfully loaded vm state\n");
@@ -115,20 +115,13 @@ static void process_incoming_migration_co(void *opaque)
     }
 }
 
-static void enter_migration_coroutine(void *opaque)
-{
-    Coroutine *co = opaque;
-    qemu_coroutine_enter(co, NULL);
-}
-
 void process_incoming_migration(QEMUFile *f)
 {
     Coroutine *co = qemu_coroutine_create(process_incoming_migration_co);
     int fd = qemu_get_fd(f);
 
     assert(fd != -1);
-    socket_set_nonblock(fd);
-    qemu_set_fd_handler(fd, enter_migration_coroutine, NULL, co);
+    qemu_set_nonblock(fd);
     qemu_coroutine_enter(co, f);
 }
 
@@ -204,11 +197,11 @@ MigrationInfo *qmp_query_migrate(Error **errp)
         info->ram->remaining = ram_bytes_remaining();
         info->ram->total = ram_bytes_total();
         info->ram->duplicate = dup_mig_pages_transferred();
+        info->ram->skipped = skipped_mig_pages_transferred();
         info->ram->normal = norm_mig_pages_transferred();
         info->ram->normal_bytes = norm_mig_bytes_transferred();
         info->ram->dirty_pages_rate = s->dirty_pages_rate;
 
-
         if (blk_mig_active()) {
             info->has_disk = true;
             info->disk = g_malloc0(sizeof(*info->disk));
@@ -234,6 +227,7 @@ MigrationInfo *qmp_query_migrate(Error **errp)
         info->ram->remaining = 0;
         info->ram->total = ram_bytes_total();
         info->ram->duplicate = dup_mig_pages_transferred();
+        info->ram->skipped = skipped_mig_pages_transferred();
         info->ram->normal = norm_mig_pages_transferred();
         info->ram->normal_bytes = norm_mig_bytes_transferred();
         break;
@@ -268,81 +262,54 @@ void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params,
 
 /* shared migration helpers */
 
-static int migrate_fd_cleanup(MigrationState *s)
+static void migrate_fd_cleanup(void *opaque)
 {
-    int ret = 0;
+    MigrationState *s = opaque;
+
+    qemu_bh_delete(s->cleanup_bh);
+    s->cleanup_bh = NULL;
 
     if (s->file) {
         DPRINTF("closing file\n");
-        ret = qemu_fclose(s->file);
+        qemu_mutex_unlock_iothread();
+        qemu_thread_join(&s->thread);
+        qemu_mutex_lock_iothread();
+
+        qemu_fclose(s->file);
         s->file = NULL;
     }
 
-    assert(s->fd == -1);
-    return ret;
-}
+    assert(s->state != MIG_STATE_ACTIVE);
+
+    if (s->state != MIG_STATE_COMPLETED) {
+        qemu_savevm_state_cancel();
+    }
 
-void migrate_fd_error(MigrationState *s)
-{
-    DPRINTF("setting error state\n");
-    s->state = MIG_STATE_ERROR;
     notifier_list_notify(&migration_state_notifiers, s);
-    migrate_fd_cleanup(s);
 }
 
-static void migrate_fd_completed(MigrationState *s)
+static void migrate_finish_set_state(MigrationState *s, int new_state)
 {
-    DPRINTF("setting completed state\n");
-    if (migrate_fd_cleanup(s) < 0) {
-        s->state = MIG_STATE_ERROR;
-    } else {
-        s->state = MIG_STATE_COMPLETED;
-        runstate_set(RUN_STATE_POSTMIGRATE);
+    if (__sync_val_compare_and_swap(&s->state, MIG_STATE_ACTIVE,
+                                    new_state) == new_state) {
+        trace_migrate_set_state(new_state);
     }
-    notifier_list_notify(&migration_state_notifiers, s);
 }
 
-static ssize_t migrate_fd_put_buffer(MigrationState *s, const void *data,
-                                     size_t size)
+void migrate_fd_error(MigrationState *s)
 {
-    ssize_t ret;
-
-    if (s->state != MIG_STATE_ACTIVE) {
-        return -EIO;
-    }
-
-    do {
-        ret = s->write(s, data, size);
-    } while (ret == -1 && ((s->get_error(s)) == EINTR));
-
-    if (ret == -1)
-        ret = -(s->get_error(s));
-
-    return ret;
+    DPRINTF("setting error state\n");
+    assert(s->file == NULL);
+    s->state = MIG_STATE_ERROR;
+    trace_migrate_set_state(MIG_STATE_ERROR);
+    notifier_list_notify(&migration_state_notifiers, s);
 }
 
 static void migrate_fd_cancel(MigrationState *s)
 {
-    if (s->state != MIG_STATE_ACTIVE)
-        return;
-
     DPRINTF("cancelling migration\n");
 
-    s->state = MIG_STATE_CANCELLED;
-    notifier_list_notify(&migration_state_notifiers, s);
-    qemu_savevm_state_cancel(s->file);
-
-    migrate_fd_cleanup(s);
-}
-
-int migrate_fd_close(MigrationState *s)
-{
-    int rc = 0;
-    if (s->fd != -1) {
-        rc = s->close(s);
-        s->fd = -1;
-    }
-    return rc;
+    migrate_finish_set_state(s, MIG_STATE_CANCELLED);
 }
 
 void add_migration_state_change_notifier(Notifier *notify)
@@ -382,7 +349,6 @@ static MigrationState *migrate_init(const MigrationParams *params)
            sizeof(enabled_capabilities));
 
     memset(s, 0, sizeof(*s));
-    s->bandwidth_limit = bandwidth_limit;
     s->params = *params;
     memcpy(s->enabled_capabilities, enabled_capabilities,
            sizeof(enabled_capabilities));
@@ -390,8 +356,9 @@ static MigrationState *migrate_init(const MigrationParams *params)
 
     s->bandwidth_limit = bandwidth_limit;
     s->state = MIG_STATE_SETUP;
-    s->total_time = qemu_get_clock_ms(rt_clock);
+    trace_migrate_set_state(MIG_STATE_SETUP);
 
+    s->total_time = qemu_get_clock_ms(rt_clock);
     return s;
 }
 
@@ -488,10 +455,15 @@ void qmp_migrate_set_speed(int64_t value, Error **errp)
     if (value < 0) {
         value = 0;
     }
+    if (value > SIZE_MAX) {
+        value = SIZE_MAX;
+    }
 
     s = migrate_get_current();
     s->bandwidth_limit = value;
-    qemu_file_set_rate_limit(s->file, s->bandwidth_limit);
+    if (s->file) {
+        qemu_file_set_rate_limit(s->file, s->bandwidth_limit / XFER_LIMIT_RATIO);
+    }
 }
 
 void qmp_migrate_set_downtime(double value, Error **errp)
@@ -521,227 +493,52 @@ int64_t migrate_xbzrle_cache_size(void)
 
 /* migration thread support */
 
-
-static ssize_t buffered_flush(MigrationState *s)
-{
-    size_t offset = 0;
-    ssize_t ret = 0;
-
-    DPRINTF("flushing %zu byte(s) of data\n", s->buffer_size);
-
-    while (s->bytes_xfer < s->xfer_limit && offset < s->buffer_size) {
-        size_t to_send = MIN(s->buffer_size - offset, s->xfer_limit - s->bytes_xfer);
-        ret = migrate_fd_put_buffer(s, s->buffer + offset, to_send);
-        if (ret <= 0) {
-            DPRINTF("error flushing data, %zd\n", ret);
-            break;
-        } else {
-            DPRINTF("flushed %zd byte(s)\n", ret);
-            offset += ret;
-            s->bytes_xfer += ret;
-        }
-    }
-
-    DPRINTF("flushed %zu of %zu byte(s)\n", offset, s->buffer_size);
-    memmove(s->buffer, s->buffer + offset, s->buffer_size - offset);
-    s->buffer_size -= offset;
-
-    if (ret < 0) {
-        return ret;
-    }
-    return offset;
-}
-
-static int buffered_put_buffer(void *opaque, const uint8_t *buf,
-                               int64_t pos, int size)
-{
-    MigrationState *s = opaque;
-    ssize_t error;
-
-    DPRINTF("putting %d bytes at %" PRId64 "\n", size, pos);
-
-    error = qemu_file_get_error(s->file);
-    if (error) {
-        DPRINTF("flush when error, bailing: %s\n", strerror(-error));
-        return error;
-    }
-
-    if (size <= 0) {
-        return size;
-    }
-
-    if (size > (s->buffer_capacity - s->buffer_size)) {
-        DPRINTF("increasing buffer capacity from %zu by %zu\n",
-                s->buffer_capacity, size + 1024);
-
-        s->buffer_capacity += size + 1024;
-
-        s->buffer = g_realloc(s->buffer, s->buffer_capacity);
-    }
-
-    memcpy(s->buffer + s->buffer_size, buf, size);
-    s->buffer_size += size;
-
-    return size;
-}
-
-static int buffered_close(void *opaque)
-{
-    MigrationState *s = opaque;
-    ssize_t ret = 0;
-    int ret2;
-
-    DPRINTF("closing\n");
-
-    s->xfer_limit = INT_MAX;
-    while (!qemu_file_get_error(s->file) && s->buffer_size) {
-        ret = buffered_flush(s);
-        if (ret < 0) {
-            break;
-        }
-    }
-
-    ret2 = migrate_fd_close(s);
-    if (ret >= 0) {
-        ret = ret2;
-    }
-    s->complete = true;
-    return ret;
-}
-
-static int buffered_get_fd(void *opaque)
-{
-    MigrationState *s = opaque;
-
-    return s->fd;
-}
-
-/*
- * The meaning of the return values is:
- *   0: We can continue sending
- *   1: Time to stop
- *   negative: There has been an error
- */
-static int buffered_rate_limit(void *opaque)
-{
-    MigrationState *s = opaque;
-    int ret;
-
-    ret = qemu_file_get_error(s->file);
-    if (ret) {
-        return ret;
-    }
-
-    if (s->bytes_xfer > s->xfer_limit) {
-        return 1;
-    }
-
-    return 0;
-}
-
-static int64_t buffered_set_rate_limit(void *opaque, int64_t new_rate)
-{
-    MigrationState *s = opaque;
-    if (qemu_file_get_error(s->file)) {
-        goto out;
-    }
-    if (new_rate > SIZE_MAX) {
-        new_rate = SIZE_MAX;
-    }
-
-    s->xfer_limit = new_rate / XFER_LIMIT_RATIO;
-
-out:
-    return s->xfer_limit;
-}
-
-static int64_t buffered_get_rate_limit(void *opaque)
-{
-    MigrationState *s = opaque;
-
-    return s->xfer_limit;
-}
-
-static bool migrate_fd_put_ready(MigrationState *s, uint64_t max_size)
-{
-    int ret;
-    uint64_t pending_size;
-    bool last_round = false;
-
-    qemu_mutex_lock_iothread();
-    if (s->state != MIG_STATE_ACTIVE) {
-        DPRINTF("put_ready returning because of non-active state\n");
-        qemu_mutex_unlock_iothread();
-        return false;
-    }
-    if (s->first_time) {
-        s->first_time = false;
-        DPRINTF("beginning savevm\n");
-        ret = qemu_savevm_state_begin(s->file, &s->params);
-        if (ret < 0) {
-            DPRINTF("failed, %d\n", ret);
-            migrate_fd_error(s);
-            qemu_mutex_unlock_iothread();
-            return false;
-        }
-    }
-
-    DPRINTF("iterate\n");
-    pending_size = qemu_savevm_state_pending(s->file, max_size);
-    DPRINTF("pending size %lu max %lu\n", pending_size, max_size);
-    if (pending_size >= max_size) {
-        ret = qemu_savevm_state_iterate(s->file);
-        if (ret < 0) {
-            migrate_fd_error(s);
-        }
-    } else {
-        int old_vm_running = runstate_is_running();
-        int64_t start_time, end_time;
-
-        DPRINTF("done iterating\n");
-        start_time = qemu_get_clock_ms(rt_clock);
-        qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
-        if (old_vm_running) {
-            vm_stop(RUN_STATE_FINISH_MIGRATE);
-        } else {
-            vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
-        }
-
-        if (qemu_savevm_state_complete(s->file) < 0) {
-            migrate_fd_error(s);
-        } else {
-            migrate_fd_completed(s);
-        }
-        end_time = qemu_get_clock_ms(rt_clock);
-        s->total_time = end_time - s->total_time;
-        s->downtime = end_time - start_time;
-        if (s->state != MIG_STATE_COMPLETED) {
-            if (old_vm_running) {
-                vm_start();
-            }
-        }
-        last_round = true;
-    }
-    qemu_mutex_unlock_iothread();
-
-    return last_round;
-}
-
-static void *buffered_file_thread(void *opaque)
+static void *migration_thread(void *opaque)
 {
     MigrationState *s = opaque;
     int64_t initial_time = qemu_get_clock_ms(rt_clock);
+    int64_t initial_bytes = 0;
     int64_t max_size = 0;
-    bool last_round = false;
-
-    while (true) {
-        int64_t current_time = qemu_get_clock_ms(rt_clock);
+    int64_t start_time = initial_time;
+    bool old_vm_running = false;
+
+    DPRINTF("beginning savevm\n");
+    qemu_savevm_state_begin(s->file, &s->params);
+
+    while (s->state == MIG_STATE_ACTIVE) {
+        int64_t current_time;
+        uint64_t pending_size;
+
+        if (!qemu_file_rate_limit(s->file)) {
+            DPRINTF("iterate\n");
+            pending_size = qemu_savevm_state_pending(s->file, max_size);
+            DPRINTF("pending size %lu max %lu\n", pending_size, max_size);
+            if (pending_size && pending_size >= max_size) {
+                qemu_savevm_state_iterate(s->file);
+            } else {
+                DPRINTF("done iterating\n");
+                qemu_mutex_lock_iothread();
+                start_time = qemu_get_clock_ms(rt_clock);
+                qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
+                old_vm_running = runstate_is_running();
+                vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
+                qemu_file_set_rate_limit(s->file, INT_MAX);
+                qemu_savevm_state_complete(s->file);
+                qemu_mutex_unlock_iothread();
+                if (!qemu_file_get_error(s->file)) {
+                    migrate_finish_set_state(s, MIG_STATE_COMPLETED);
+                    break;
+                }
+            }
+        }
 
-        if (s->complete) {
+        if (qemu_file_get_error(s->file)) {
+            migrate_finish_set_state(s, MIG_STATE_ERROR);
             break;
         }
+        current_time = qemu_get_clock_ms(rt_clock);
         if (current_time >= initial_time + BUFFER_DELAY) {
-            uint64_t transferred_bytes = s->bytes_xfer;
+            uint64_t transferred_bytes = qemu_ftell(s->file) - initial_bytes;
             uint64_t time_spent = current_time - initial_time;
             double bandwidth = transferred_bytes / time_spent;
             max_size = bandwidth * migrate_max_downtime() / 1000000;
@@ -749,54 +546,52 @@ static void *buffered_file_thread(void *opaque)
             DPRINTF("transferred %" PRIu64 " time_spent %" PRIu64
                     " bandwidth %g max_size %" PRId64 "\n",
                     transferred_bytes, time_spent, bandwidth, max_size);
+            /* if we haven't sent anything, we don't want to recalculate
+               10000 is a small enough number for our purposes */
+            if (s->dirty_bytes_rate && transferred_bytes > 10000) {
+                s->expected_downtime = s->dirty_bytes_rate / bandwidth;
+            }
 
-            s->bytes_xfer = 0;
+            qemu_file_reset_rate_limit(s->file);
             initial_time = current_time;
+            initial_bytes = qemu_ftell(s->file);
         }
-        if (!last_round && (s->bytes_xfer >= s->xfer_limit)) {
+        if (qemu_file_rate_limit(s->file)) {
             /* usleep expects microseconds */
             g_usleep((initial_time + BUFFER_DELAY - current_time)*1000);
         }
-        if (buffered_flush(s) < 0) {
-            break;
-        }
+    }
 
-        DPRINTF("file is ready\n");
-        if (s->bytes_xfer < s->xfer_limit) {
-            DPRINTF("notifying client\n");
-            last_round = migrate_fd_put_ready(s, max_size);
+    qemu_mutex_lock_iothread();
+    if (s->state == MIG_STATE_COMPLETED) {
+        int64_t end_time = qemu_get_clock_ms(rt_clock);
+        s->total_time = end_time - s->total_time;
+        s->downtime = end_time - start_time;
+        runstate_set(RUN_STATE_POSTMIGRATE);
+    } else {
+        if (old_vm_running) {
+            vm_start();
         }
     }
+    qemu_bh_schedule(s->cleanup_bh);
+    qemu_mutex_unlock_iothread();
 
-    g_free(s->buffer);
     return NULL;
 }
 
-static const QEMUFileOps buffered_file_ops = {
-    .get_fd =         buffered_get_fd,
-    .put_buffer =     buffered_put_buffer,
-    .close =          buffered_close,
-    .rate_limit =     buffered_rate_limit,
-    .get_rate_limit = buffered_get_rate_limit,
-    .set_rate_limit = buffered_set_rate_limit,
-};
-
 void migrate_fd_connect(MigrationState *s)
 {
     s->state = MIG_STATE_ACTIVE;
-    s->bytes_xfer = 0;
-    s->buffer = NULL;
-    s->buffer_size = 0;
-    s->buffer_capacity = 0;
-
-    s->first_time = true;
+    trace_migrate_set_state(MIG_STATE_ACTIVE);
 
-    s->xfer_limit = s->bandwidth_limit / XFER_LIMIT_RATIO;
-    s->complete = false;
+    /* This is a best 1st approximation. ns to ms */
+    s->expected_downtime = max_downtime/1000000;
+    s->cleanup_bh = qemu_bh_new(migrate_fd_cleanup, s);
 
-    s->file = qemu_fopen_ops(s, &buffered_file_ops);
+    qemu_file_set_rate_limit(s->file,
+                             s->bandwidth_limit / XFER_LIMIT_RATIO);
 
-    qemu_thread_create(&s->thread, buffered_file_thread, s,
-                       QEMU_THREAD_DETACHED);
+    qemu_thread_create(&s->thread, migration_thread, s,
+                       QEMU_THREAD_JOINABLE);
     notifier_list_notify(&migration_state_notifiers, s);
 }