From cfbdab951369f15de890597530076bf0119361be Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Mon, 17 Jan 2011 16:10:59 +0800 Subject: [PATCH] vhost-net: check the support of mergeable buffer outside the receive loop No need to check the support of mergeable buffer inside the recevie loop as the whole handle_rx()_xx is in the read critical region. So this patch move it ahead of the receiving loop. Signed-off-by: Jason Wang Signed-off-by: Michael S. Tsirkin --- drivers/vhost/net.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 59dad9fe52dd..9f57cd45fe8f 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -411,7 +411,7 @@ static void handle_rx_mergeable(struct vhost_net *net) .hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE }; size_t total_len = 0; - int err, headcount; + int err, headcount, mergeable; size_t vhost_hlen, sock_hlen; size_t vhost_len, sock_len; /* TODO: check that we are running from vhost_worker? */ @@ -427,6 +427,7 @@ static void handle_rx_mergeable(struct vhost_net *net) vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ? vq->log : NULL; + mergeable = vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF); while ((sock_len = peek_head_len(sock->sk))) { sock_len += sock_hlen; @@ -476,7 +477,7 @@ static void handle_rx_mergeable(struct vhost_net *net) break; } /* TODO: Should check and handle checksum. */ - if (vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF) && + if (likely(mergeable) && memcpy_toiovecend(vq->hdr, (unsigned char *)&headcount, offsetof(typeof(hdr), num_buffers), sizeof hdr.num_buffers)) { -- 2.20.1