From patchwork Tue Jun 7 16:28:26 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 9163989 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 0C13B60832 for ; Wed, 8 Jun 2016 09:45:14 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EF3342835E for ; Wed, 8 Jun 2016 09:45:13 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E3D9D28390; Wed, 8 Jun 2016 09:45:13 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.9 required=2.0 tests=BAYES_00, DATE_IN_PAST_12_24, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 885F22835E for ; Wed, 8 Jun 2016 09:45:13 +0000 (UTC) Received: from localhost ([::1]:55567 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bAa2y-0003bD-IZ for patchwork-qemu-devel@patchwork.kernel.org; Wed, 08 Jun 2016 05:45:12 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60735) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bAZjp-0002Tl-QE for qemu-devel@nongnu.org; Wed, 08 Jun 2016 05:25:29 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bAZji-0003l0-M0 for qemu-devel@nongnu.org; Wed, 08 Jun 2016 05:25:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42114) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bAZji-0003ku-Db for qemu-devel@nongnu.org; Wed, 08 Jun 2016 05:25:18 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id F0FCCC0828A4; Wed, 8 Jun 2016 09:25:17 +0000 (UTC) Received: from localhost (ovpn-112-67.ams2.redhat.com [10.36.112.67]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u589PGl6013159; Wed, 8 Jun 2016 05:25:17 -0400 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Date: Tue, 7 Jun 2016 17:28:26 +0100 Message-Id: <1465316911-20052-3-git-send-email-stefanha@redhat.com> In-Reply-To: <1465316911-20052-1-git-send-email-stefanha@redhat.com> References: <1465316911-20052-1-git-send-email-stefanha@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Wed, 08 Jun 2016 09:25:18 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v3 2/7] virtio-blk: multiqueue batch notify X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Fam Zheng , Stefan Hajnoczi , Ming Lei , Christian Borntraeger , Roman Pen , Paolo Bonzini Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP The batch notification BH needs to know which virtqueues to notify when multiqueue is enabled. Use a bitmap to track the virtqueues with pending notifications. At this point there is only one virtqueue so hard-code virtqueue index 0. A later patch will switch to real virtqueue indices. Signed-off-by: Stefan Hajnoczi --- hw/block/dataplane/virtio-blk.c | 29 +++++++++++++++++++++++------ 1 file changed, 23 insertions(+), 6 deletions(-) diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c index 3cb97c9..4439c7b 100644 --- a/hw/block/dataplane/virtio-blk.c +++ b/hw/block/dataplane/virtio-blk.c @@ -34,8 +34,8 @@ struct VirtIOBlockDataPlane { VirtIODevice *vdev; VirtQueue *vq; /* virtqueue vring */ - EventNotifier *guest_notifier; /* irq */ QEMUBH *bh; /* bh for guest notification */ + unsigned long *batch_notify_vqs; Notifier insert_notifier, remove_notifier; @@ -54,18 +54,34 @@ struct VirtIOBlockDataPlane { /* Raise an interrupt to signal guest, if necessary */ void virtio_blk_data_plane_notify(VirtIOBlockDataPlane *s) { + set_bit(0, s->batch_notify_vqs); qemu_bh_schedule(s->bh); } static void notify_guest_bh(void *opaque) { VirtIOBlockDataPlane *s = opaque; + unsigned nvqs = s->conf->num_queues; + unsigned long bitmap[BITS_TO_LONGS(nvqs)]; + unsigned j; - if (!virtio_should_notify(s->vdev, s->vq)) { - return; + memcpy(bitmap, s->batch_notify_vqs, sizeof(bitmap)); + memset(s->batch_notify_vqs, 0, sizeof(bitmap)); + + for (j = 0; j < nvqs; j += BITS_PER_LONG) { + unsigned long bits = bitmap[j]; + + while (bits != 0) { + unsigned i = j + ctzl(bits); + VirtQueue *vq = virtio_get_queue(s->vdev, i); + + if (virtio_should_notify(s->vdev, vq)) { + event_notifier_set(virtio_queue_get_guest_notifier(vq)); + } + + bits &= bits - 1; /* clear right-most bit */ + } } - - event_notifier_set(s->guest_notifier); } static void data_plane_set_up_op_blockers(VirtIOBlockDataPlane *s) @@ -157,6 +173,7 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *conf, } s->ctx = iothread_get_aio_context(s->iothread); s->bh = aio_bh_new(s->ctx, notify_guest_bh, s); + s->batch_notify_vqs = bitmap_new(conf->num_queues); s->insert_notifier.notify = data_plane_blk_insert_notifier; s->remove_notifier.notify = data_plane_blk_remove_notifier; @@ -179,6 +196,7 @@ void virtio_blk_data_plane_destroy(VirtIOBlockDataPlane *s) data_plane_remove_op_blockers(s); notifier_remove(&s->insert_notifier); notifier_remove(&s->remove_notifier); + g_free(s->batch_notify_vqs); qemu_bh_delete(s->bh); object_unref(OBJECT(s->iothread)); g_free(s); @@ -217,7 +235,6 @@ void virtio_blk_data_plane_start(VirtIOBlockDataPlane *s) "ensure -enable-kvm is set\n", r); goto fail_guest_notifiers; } - s->guest_notifier = virtio_queue_get_guest_notifier(s->vq); /* Set up virtqueue notify */ r = k->set_host_notifier(qbus->parent, 0, true);