From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH v3 16/18] vhost: don't bother with copying iovec in handle_tx() Date: Wed, 4 Feb 2015 10:13:52 +0100 Message-ID: <20150204091352.GF9920@redhat.com> References: <20150204063730.GG29656@ZenIV.linux.org.uk> <1423032009-18367-16-git-send-email-viro@ZenIV.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, David Miller , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org To: Al Viro Return-path: Content-Disposition: inline In-Reply-To: <1423032009-18367-16-git-send-email-viro@ZenIV.linux.org.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org List-Id: netdev.vger.kernel.org On Wed, Feb 04, 2015 at 06:40:07AM +0000, Al Viro wrote: > From: Al Viro > > just advance the msg.msg_iter and be done with that. > > Cc: Michael S. Tsirkin > Cc: kvm@vger.kernel.org > Cc: virtualization@lists.linux-foundation.org > Signed-off-by: Al Viro Acked-by: Michael S. Tsirkin > --- > drivers/vhost/net.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > index 6906f76..d86cc9b 100644 > --- a/drivers/vhost/net.c > +++ b/drivers/vhost/net.c > @@ -336,7 +336,7 @@ static void handle_tx(struct vhost_net *net) > { > struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; > struct vhost_virtqueue *vq = &nvq->vq; > - unsigned out, in, s; > + unsigned out, in; > int head; > struct msghdr msg = { > .msg_name = NULL, > @@ -395,16 +395,17 @@ static void handle_tx(struct vhost_net *net) > break; > } > /* Skip header. TODO: support TSO. */ > - s = move_iovec_hdr(vq->iov, nvq->hdr, hdr_size, out); > len = iov_length(vq->iov, out); > iov_iter_init(&msg.msg_iter, WRITE, vq->iov, out, len); > + iov_iter_advance(&msg.msg_iter, hdr_size); > /* Sanity check */ > - if (!len) { > + if (!iov_iter_count(&msg.msg_iter)) { > vq_err(vq, "Unexpected header len for TX: " > "%zd expected %zd\n", > - iov_length(nvq->hdr, s), hdr_size); > + len, hdr_size); > break; > } > + len = iov_iter_count(&msg.msg_iter); > > zcopy_used = zcopy && len >= VHOST_GOODCOPY_LEN > && (nvq->upend_idx + 1) % UIO_MAXIOV != > -- > 2.1.4