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-rw-r--r--qemu/iothread.c170
1 files changed, 170 insertions, 0 deletions
diff --git a/qemu/iothread.c b/qemu/iothread.c
new file mode 100644
index 000000000..da6ce7b30
--- /dev/null
+++ b/qemu/iothread.c
@@ -0,0 +1,170 @@
+/*
+ * Event loop thread
+ *
+ * Copyright Red Hat Inc., 2013
+ *
+ * Authors:
+ * Stefan Hajnoczi <stefanha@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 "qom/object.h"
+#include "qom/object_interfaces.h"
+#include "qemu/module.h"
+#include "block/aio.h"
+#include "sysemu/iothread.h"
+#include "qmp-commands.h"
+#include "qemu/error-report.h"
+#include "qemu/rcu.h"
+
+typedef ObjectClass IOThreadClass;
+
+#define IOTHREAD_GET_CLASS(obj) \
+ OBJECT_GET_CLASS(IOThreadClass, obj, TYPE_IOTHREAD)
+#define IOTHREAD_CLASS(klass) \
+ OBJECT_CLASS_CHECK(IOThreadClass, klass, TYPE_IOTHREAD)
+
+static void *iothread_run(void *opaque)
+{
+ IOThread *iothread = opaque;
+ bool blocking;
+
+ rcu_register_thread();
+
+ qemu_mutex_lock(&iothread->init_done_lock);
+ iothread->thread_id = qemu_get_thread_id();
+ qemu_cond_signal(&iothread->init_done_cond);
+ qemu_mutex_unlock(&iothread->init_done_lock);
+
+ while (!iothread->stopping) {
+ aio_context_acquire(iothread->ctx);
+ blocking = true;
+ while (!iothread->stopping && aio_poll(iothread->ctx, blocking)) {
+ /* Progress was made, keep going */
+ blocking = false;
+ }
+ aio_context_release(iothread->ctx);
+ }
+
+ rcu_unregister_thread();
+ return NULL;
+}
+
+static void iothread_instance_finalize(Object *obj)
+{
+ IOThread *iothread = IOTHREAD(obj);
+
+ if (!iothread->ctx) {
+ return;
+ }
+ iothread->stopping = true;
+ aio_notify(iothread->ctx);
+ qemu_thread_join(&iothread->thread);
+ qemu_cond_destroy(&iothread->init_done_cond);
+ qemu_mutex_destroy(&iothread->init_done_lock);
+ aio_context_unref(iothread->ctx);
+}
+
+static void iothread_complete(UserCreatable *obj, Error **errp)
+{
+ Error *local_error = NULL;
+ IOThread *iothread = IOTHREAD(obj);
+
+ iothread->stopping = false;
+ iothread->thread_id = -1;
+ iothread->ctx = aio_context_new(&local_error);
+ if (!iothread->ctx) {
+ error_propagate(errp, local_error);
+ return;
+ }
+
+ qemu_mutex_init(&iothread->init_done_lock);
+ qemu_cond_init(&iothread->init_done_cond);
+
+ /* This assumes we are called from a thread with useful CPU affinity for us
+ * to inherit.
+ */
+ qemu_thread_create(&iothread->thread, "iothread", iothread_run,
+ iothread, QEMU_THREAD_JOINABLE);
+
+ /* Wait for initialization to complete */
+ qemu_mutex_lock(&iothread->init_done_lock);
+ while (iothread->thread_id == -1) {
+ qemu_cond_wait(&iothread->init_done_cond,
+ &iothread->init_done_lock);
+ }
+ qemu_mutex_unlock(&iothread->init_done_lock);
+}
+
+static void iothread_class_init(ObjectClass *klass, void *class_data)
+{
+ UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
+ ucc->complete = iothread_complete;
+}
+
+static const TypeInfo iothread_info = {
+ .name = TYPE_IOTHREAD,
+ .parent = TYPE_OBJECT,
+ .class_init = iothread_class_init,
+ .instance_size = sizeof(IOThread),
+ .instance_finalize = iothread_instance_finalize,
+ .interfaces = (InterfaceInfo[]) {
+ {TYPE_USER_CREATABLE},
+ {}
+ },
+};
+
+static void iothread_register_types(void)
+{
+ type_register_static(&iothread_info);
+}
+
+type_init(iothread_register_types)
+
+char *iothread_get_id(IOThread *iothread)
+{
+ return object_get_canonical_path_component(OBJECT(iothread));
+}
+
+AioContext *iothread_get_aio_context(IOThread *iothread)
+{
+ return iothread->ctx;
+}
+
+static int query_one_iothread(Object *object, void *opaque)
+{
+ IOThreadInfoList ***prev = opaque;
+ IOThreadInfoList *elem;
+ IOThreadInfo *info;
+ IOThread *iothread;
+
+ iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD);
+ if (!iothread) {
+ return 0;
+ }
+
+ info = g_new0(IOThreadInfo, 1);
+ info->id = iothread_get_id(iothread);
+ info->thread_id = iothread->thread_id;
+
+ elem = g_new0(IOThreadInfoList, 1);
+ elem->value = info;
+ elem->next = NULL;
+
+ **prev = elem;
+ *prev = &elem->next;
+ return 0;
+}
+
+IOThreadInfoList *qmp_query_iothreads(Error **errp)
+{
+ IOThreadInfoList *head = NULL;
+ IOThreadInfoList **prev = &head;
+ Object *container = object_get_objects_root();
+
+ object_child_foreach(container, query_one_iothread, &prev);
+ return head;
+}