diff mbox

[dpdk-dev,v4,7/7] virtio: pick simple rx/tx func

Message ID 1445515791-25909-8-git-send-email-huawei.xie@intel.com (mailing list archive)
State Superseded, archived
Headers

Commit Message

Huawei Xie Oct. 22, 2015, 12:09 p.m. UTC 
Changes in v4:
Check merge-able feature when select simple rx/tx functions.

simple rx/tx func is chose when merge-able rx is disabled and user specifies single segment and
no offload support.

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 drivers/net/virtio/virtio_rxtx.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

Comments

Stephen Hemminger Oct. 22, 2015, 4:58 p.m. UTC | #1 
On Thu, 22 Oct 2015 20:09:51 +0800
Huawei Xie <huawei.xie@intel.com> wrote:

> +	/* Use simple rx/tx func if single segment and no offloads */
> +	if ((tx_conf->txq_flags & VIRTIO_SIMPLE_FLAGS) == VIRTIO_SIMPLE_FLAGS &&
> +	     !vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF))

Since with QEMU/KVM the code will negotiate to use MRG_RXBUF, this
code path will not get used in common case anyway.
Huawei Xie Oct. 23, 2015, 1:38 a.m. UTC | #2 
On 10/23/2015 12:59 AM, Stephen Hemminger wrote:
> On Thu, 22 Oct 2015 20:09:51 +0800
> Huawei Xie <huawei.xie@intel.com> wrote:
>
>> +	/* Use simple rx/tx func if single segment and no offloads */
>> +	if ((tx_conf->txq_flags & VIRTIO_SIMPLE_FLAGS) == VIRTIO_SIMPLE_FLAGS &&
>> +	     !vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF))
> Since with QEMU/KVM the code will negotiate to use MRG_RXBUF, this
> code path will not get used in common case anyway.
>
Yes, the common configuration is merge-able enabled.
We need to add mrg_rxbuf=off(in qemu command line), or disable
merge-able feature(in switch application) through vhost API for
non-mergable.
diff mbox

Patch

diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index 947fc46..0f1daf2 100644
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -53,6 +53,7 @@ 
 
 #include "virtio_logs.h"
 #include "virtio_ethdev.h"
+#include "virtio_pci.h"
 #include "virtqueue.h"
 #include "virtio_rxtx.h"
 
@@ -62,6 +63,10 @@ 
 #define  VIRTIO_DUMP_PACKET(m, len) do { } while (0)
 #endif
 
+
+#define VIRTIO_SIMPLE_FLAGS ((uint32_t)ETH_TXQ_FLAGS_NOMULTSEGS | \
+	ETH_TXQ_FLAGS_NOOFFLOADS)
+
 static int use_simple_rxtx;
 
 static void
@@ -459,6 +464,7 @@  virtio_dev_tx_queue_setup(struct rte_eth_dev *dev,
 			const struct rte_eth_txconf *tx_conf)
 {
 	uint8_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_TQ_QUEUE_IDX;
+	struct virtio_hw *hw = dev->data->dev_private;
 	struct virtqueue *vq;
 	uint16_t tx_free_thresh;
 	int ret;
@@ -471,6 +477,15 @@  virtio_dev_tx_queue_setup(struct rte_eth_dev *dev,
 		return -EINVAL;
 	}
 
+	/* Use simple rx/tx func if single segment and no offloads */
+	if ((tx_conf->txq_flags & VIRTIO_SIMPLE_FLAGS) == VIRTIO_SIMPLE_FLAGS &&
+	     !vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF)) {
+		PMD_INIT_LOG(INFO, "Using simple rx/tx path");
+		dev->tx_pkt_burst = virtio_xmit_pkts_simple;
+		dev->rx_pkt_burst = virtio_recv_pkts_vec;
+		use_simple_rxtx = 1;
+	}
+
 	ret = virtio_dev_queue_setup(dev, VTNET_TQ, queue_idx, vtpci_queue_idx,
 			nb_desc, socket_id, &vq);
 	if (ret < 0) {