From patchwork Wed Apr 4 12:54:02 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wei Xu X-Patchwork-Id: 894988 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 40GR6H1LtTz9s0n for ; Wed, 4 Apr 2018 23:05:59 +1000 (AEST) Received: from localhost ([::1]:56621 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f3i6u-0000iD-Mi for incoming@patchwork.ozlabs.org; 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Wed, 4 Apr 2018 12:55:50 +0000 (UTC) From: wexu@redhat.com To: wexu@redhat.com, jasowang@redhat.com, mst@redhat.com, tiwei.bie@intel.com, jfreimann@redhat.com, qemu-devel@nongnu.org Date: Wed, 4 Apr 2018 20:54:02 +0800 Message-Id: <1522846444-31725-7-git-send-email-wexu@redhat.com> In-Reply-To: <1522846444-31725-1-git-send-email-wexu@redhat.com> References: <1522846444-31725-1-git-send-email-wexu@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Wed, 04 Apr 2018 12:55:52 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Wed, 04 Apr 2018 12:55:52 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'wexu@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH 6/8] virtio: flush/push support for packed ring 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: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Wei Xu Signed-off-by: Wei Xu --- hw/virtio/virtio.c | 104 +++++++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 90 insertions(+), 14 deletions(-) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 95a4681..def07c6 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -26,6 +26,7 @@ #define AVAIL_DESC_PACKED(b) ((b) << 7) #define USED_DESC_PACKED(b) ((b) << 15) +#define VIRTQ_F_DESC_USED(w) (AVAIL_DESC_PACKED(w) | USED_DESC_PACKED(w)) /* * The alignment to use between consumer and producer parts of vring. @@ -636,19 +637,11 @@ bool virtqueue_rewind(VirtQueue *vq, unsigned int num) } /* Called within rcu_read_lock(). */ -void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, +static void virtqueue_fill_split(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len, unsigned int idx) { VRingUsedElem uelem; - trace_virtqueue_fill(vq, elem, len, idx); - - virtqueue_unmap_sg(vq, elem, len); - - if (unlikely(vq->vdev->broken)) { - return; - } - if (unlikely(!vq->vring.used)) { return; } @@ -660,16 +653,66 @@ void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, vring_used_write(vq, &uelem, idx); } -/* Called within rcu_read_lock(). */ -void virtqueue_flush(VirtQueue *vq, unsigned int count) +static void virtqueue_fill_packed(VirtQueue *vq, const VirtQueueElement *elem) { - uint16_t old, new; + uint16_t i, w, head; + VRingMemoryRegionCaches *caches; + VRingDescPacked desc = { + .addr = 0, + .flags = 0, + }; + + if (unlikely(!vq->packed.desc)) { + return; + } + + w = elem->wrap_counter; + caches = vring_get_region_caches(vq); + for (i = 0; i < elem->count; i++) { + head = (elem->index + i) % vq->packed.num; + /* Don't toggle the first one since it is the originally one */ + if ((i > 0) && (!head)) { + w ^= 1; + } + + desc.id = elem->index; + desc.flags = VIRTQ_F_DESC_USED(w); + desc.len = elem->len[i]; + virtio_tswap16s(vq->vdev, &desc.id); + virtio_tswap32s(vq->vdev, &desc.len); + virtio_tswap16s(vq->vdev, &desc.flags); + address_space_write_cached(&caches->desc, + sizeof(VRingDescPacked) * head, &desc, + sizeof(VRingDescPacked)); + address_space_cache_invalidate(&caches->desc, + sizeof(VRingDescPacked) * head, + sizeof(VRingDescPacked)); + } +} + +void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, + unsigned int len, unsigned int idx) +{ + trace_virtqueue_fill(vq, elem, len, idx); + + virtqueue_unmap_sg(vq, elem, len); if (unlikely(vq->vdev->broken)) { - vq->inuse -= count; return; } + if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { + virtqueue_fill_packed(vq, elem); + } else { + virtqueue_fill_split(vq, elem, len, idx); + } +} + +/* Called within rcu_read_lock(). */ +static void virtqueue_flush_split(VirtQueue *vq, unsigned int count) +{ + uint16_t old, new; + if (unlikely(!vq->vring.used)) { return; } @@ -685,12 +728,45 @@ void virtqueue_flush(VirtQueue *vq, unsigned int count) vq->signalled_used_valid = false; } +static void virtqueue_flush_packed(VirtQueue *vq, unsigned int count) +{ + if (unlikely(!vq->packed.desc)) { + return; + } + + vq->inuse -= count; + + /* FIXME: is this correct? */ + if (vq->inuse) { + return; + } +} + +void virtqueue_flush(VirtQueue *vq, unsigned int count) +{ + if (unlikely(vq->vdev->broken)) { + vq->inuse -= count; + return; + } + + if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { + virtqueue_flush_packed(vq, count); + } else { + virtqueue_flush_split(vq, count); + } +} + void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len) { rcu_read_lock(); virtqueue_fill(vq, elem, len, 0); - virtqueue_flush(vq, 1); + if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { + /* FIXME: How to deal with the length field for chained desc */ + virtqueue_flush(vq, elem->count); + } else { + virtqueue_flush(vq, 1); + } rcu_read_unlock(); }