From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36838) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WO6MO-0006AC-1J for qemu-devel@nongnu.org; Thu, 13 Mar 2014 10:11:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WO6MI-0006Yv-KF for qemu-devel@nongnu.org; Thu, 13 Mar 2014 10:11:47 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36840) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WO6MI-0006Yi-Cr for qemu-devel@nongnu.org; Thu, 13 Mar 2014 10:11:42 -0400 From: Stefan Hajnoczi Date: Thu, 13 Mar 2014 15:10:54 +0100 Message-Id: <1394719868-24312-11-git-send-email-stefanha@redhat.com> In-Reply-To: <1394719868-24312-1-git-send-email-stefanha@redhat.com> References: <1394719868-24312-1-git-send-email-stefanha@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PULL v2 for-2.0 10/24] iothread: add I/O thread object List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , Stefan Hajnoczi , Anthony Liguori This is a stand-in for Michael Roth's QContext. I expect this to be replaced once QContext is completed. The IOThread object is an AioContext event loop thread. This patch adds the concept of multiple event loop threads, allowing users to define them. When SMP guests run on SMP hosts it makes sense to instantiate multiple IOThreads. This spreads event loop processing across multiple cores. Note that additional patches are required to actually bind a device to an IOThread. [Andreas F=C3=A4rber pointed out that the embedded par= ent object instance should be called "parent_obj" and have a newline afterwards. This patch has been changed to reflect this. -- Stefan] Signed-off-by: Stefan Hajnoczi --- Makefile.objs | 1 + include/sysemu/iothread.h | 30 ++++++++++++ iothread.c | 120 ++++++++++++++++++++++++++++++++++++++++= ++++++ 3 files changed, 151 insertions(+) create mode 100644 include/sysemu/iothread.h create mode 100644 iothread.c diff --git a/Makefile.objs b/Makefile.objs index 5cd3d81..a6e0e2a 100644 --- a/Makefile.objs +++ b/Makefile.objs @@ -39,6 +39,7 @@ libcacard-y +=3D libcacard/vcardt.o =20 ifeq ($(CONFIG_SOFTMMU),y) common-obj-y =3D blockdev.o blockdev-nbd.o block/ +common-obj-y +=3D iothread.o common-obj-y +=3D net/ common-obj-y +=3D qdev-monitor.o device-hotplug.o common-obj-$(CONFIG_WIN32) +=3D os-win32.o diff --git a/include/sysemu/iothread.h b/include/sysemu/iothread.h new file mode 100644 index 0000000..a32214a --- /dev/null +++ b/include/sysemu/iothread.h @@ -0,0 +1,30 @@ +/* + * Event loop thread + * + * Copyright Red Hat Inc., 2013 + * + * Authors: + * Stefan Hajnoczi + * + * This work is licensed under the terms of the GNU GPL, version 2 or la= ter. + * See the COPYING file in the top-level directory. + * + */ + +#ifndef IOTHREAD_H +#define IOTHREAD_H + +#include "block/aio.h" + +#define TYPE_IOTHREAD "iothread" + +typedef struct IOThread IOThread; + +#define IOTHREAD(obj) \ + OBJECT_CHECK(IOThread, obj, TYPE_IOTHREAD) + +IOThread *iothread_find(const char *id); +char *iothread_get_id(IOThread *iothread); +AioContext *iothread_get_aio_context(IOThread *iothread); + +#endif /* IOTHREAD_H */ diff --git a/iothread.c b/iothread.c new file mode 100644 index 0000000..f263ee2 --- /dev/null +++ b/iothread.c @@ -0,0 +1,120 @@ +/* + * Event loop thread + * + * Copyright Red Hat Inc., 2013 + * + * Authors: + * Stefan Hajnoczi + * + * This work is licensed under the terms of the GNU GPL, version 2 or la= ter. + * See the COPYING file in the top-level directory. + * + */ + +#include "qom/object.h" +#include "qom/object_interfaces.h" +#include "qemu/module.h" +#include "qemu/thread.h" +#include "block/aio.h" +#include "sysemu/iothread.h" + +#define IOTHREADS_PATH "/objects" + +typedef ObjectClass IOThreadClass; +struct IOThread { + Object parent_obj; + + QemuThread thread; + AioContext *ctx; + bool stopping; +}; + +#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 =3D opaque; + + while (!iothread->stopping) { + aio_context_acquire(iothread->ctx); + while (!iothread->stopping && aio_poll(iothread->ctx, true)) { + /* Progress was made, keep going */ + } + aio_context_release(iothread->ctx); + } + return NULL; +} + +static void iothread_instance_finalize(Object *obj) +{ + IOThread *iothread =3D IOTHREAD(obj); + + iothread->stopping =3D true; + aio_notify(iothread->ctx); + qemu_thread_join(&iothread->thread); + aio_context_unref(iothread->ctx); +} + +static void iothread_complete(UserCreatable *obj, Error **errp) +{ + IOThread *iothread =3D IOTHREAD(obj); + + iothread->stopping =3D false; + iothread->ctx =3D aio_context_new(); + + /* 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); +} + +static void iothread_class_init(ObjectClass *klass, void *class_data) +{ + UserCreatableClass *ucc =3D USER_CREATABLE_CLASS(klass); + ucc->complete =3D iothread_complete; +} + +static const TypeInfo iothread_info =3D { + .name =3D TYPE_IOTHREAD, + .parent =3D TYPE_OBJECT, + .class_init =3D iothread_class_init, + .instance_size =3D sizeof(IOThread), + .instance_finalize =3D iothread_instance_finalize, + .interfaces =3D (InterfaceInfo[]) { + {TYPE_USER_CREATABLE}, + {} + }, +}; + +static void iothread_register_types(void) +{ + type_register_static(&iothread_info); +} + +type_init(iothread_register_types) + +IOThread *iothread_find(const char *id) +{ + Object *container =3D container_get(object_get_root(), IOTHREADS_PAT= H); + Object *child; + + child =3D object_property_get_link(container, id, NULL); + if (!child) { + return NULL; + } + return (IOThread *)object_dynamic_cast(child, TYPE_IOTHREAD); +} + +char *iothread_get_id(IOThread *iothread) +{ + return object_get_canonical_path_component(OBJECT(iothread)); +} + +AioContext *iothread_get_aio_context(IOThread *iothread) +{ + return iothread->ctx; +} --=20 1.8.5.3