On 06/28/2018 05:39 PM, Liu, Yong wrote:
-----Original Message-----
From: Maxime Coquelin [mailto:maxime.coque...@redhat.com]
Sent: Thursday, June 28, 2018 11:16 PM
To: Liu, Yong <yong....@intel.com>; Bie, Tiwei <tiwei....@intel.com>
Cc: Wang, Zhihong <zhihong.w...@intel.com>; dev@dpdk.org
Subject: Re: [PATCH v3 08/11] net/virtio: add in-order Rx/Tx into
selection
On 06/28/2018 11:52 PM, Marvin Liu wrote:
After IN_ORDER Rx/Tx paths added, need to update Rx/Tx path selection
logic.
Rx path select logic: If IN_ORDER is disabled will select normal Rx
path. If IN_ORDER is enabled, Rx offload and merge-able are disabled
will select simple Rx path. Otherwise will select IN_ORDER Rx path.
Tx path select logic: If IN_ORDER is disabled will select normal Tx
path. If IN_ORDER is enabled and merge-able is disabled will select
simple Tx path. Otherwise will select IN_ORDER Tx path.
Signed-off-by: Marvin Liu <yong....@intel.com>
diff --git a/drivers/net/virtio/virtio_ethdev.c
b/drivers/net/virtio/virtio_ethdev.c
index df50a571a..2b3d65f80 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1320,6 +1320,11 @@ set_rxtx_funcs(struct rte_eth_dev *eth_dev)
PMD_INIT_LOG(INFO, "virtio: using simple Rx path on port %u",
eth_dev->data->port_id);
eth_dev->rx_pkt_burst = virtio_recv_pkts_vec;
+ } else if (hw->use_inorder_rx) {
+ PMD_INIT_LOG(INFO,
+ "virtio: using inorder mergeable buffer Rx path on
port %u",
+ eth_dev->data->port_id);
+ eth_dev->rx_pkt_burst = &virtio_recv_mergeable_pkts_inorder;
} else if (vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF)) {
PMD_INIT_LOG(INFO,
"virtio: using mergeable buffer Rx path on port %u",
@@ -1335,6 +1340,10 @@ set_rxtx_funcs(struct rte_eth_dev *eth_dev)
PMD_INIT_LOG(INFO, "virtio: using simple Tx path on port %u",
eth_dev->data->port_id);
eth_dev->tx_pkt_burst = virtio_xmit_pkts_simple;
+ } else if (hw->use_inorder_tx) {
+ PMD_INIT_LOG(INFO, "virtio: using inorder Tx path on port %u",
+ eth_dev->data->port_id);
+ eth_dev->tx_pkt_burst = virtio_xmit_pkts_inorder;
} else {
PMD_INIT_LOG(INFO, "virtio: using standard Tx path on port %u",
eth_dev->data->port_id);
@@ -1871,24 +1880,24 @@ virtio_dev_configure(struct rte_eth_dev *dev)
rte_spinlock_init(&hw->state_lock);
- hw->use_simple_rx = 1;
- hw->use_simple_tx = 1;
-
#if defined RTE_ARCH_ARM64 || defined RTE_ARCH_ARM
if (!rte_cpu_get_flag_enabled(RTE_CPUFLAG_NEON)) {
hw->use_simple_rx = 0;
hw->use_simple_tx = 0;
}
#endif
- if (vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF)) {
- hw->use_simple_rx = 0;
- hw->use_simple_tx = 0;
+ if (vtpci_with_feature(hw, VIRTIO_F_IN_ORDER)) {
+ if (vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF)) {
+ hw->use_inorder_rx = 1;
+ hw->use_inorder_tx = 1;
+ } else {
+ hw->use_simple_tx = 1;
+ if (!(rx_offloads & (DEV_RX_OFFLOAD_UDP_CKSUM |
+ DEV_RX_OFFLOAD_TCP_CKSUM)))
+ hw->use_simple_rx = 1;
+ }
It seems to be wrong.
For example if IN_ORDER hasn't been negotiated, we might want to use the
simple path if no rx offload have been requested by the application.
It was the case before the patch if I'm not mistaken.
Maxime,
IN_ORDER is the prerequisite for selection simple rx/tx path. So when IN_ORDER
+ mergeable off + no rx offload will chose simple rx path.
Ok, I wonder in that case if I could just remove the simple Tx path in
my series as it is not compliant with IN_ORDER.
Tiwei, what's your take on this?
Also, I wonder if it would make sense to backport the vhost patch that
advertize IN_ORDER features to the LTS, as no functional changes, except
that it prevents using "simple/inorder" path with dequeue zero copy,
which is a good thing.
Any thoughts?
Also, with ARM platform, we force not to use simple path, but in case
IN_ORDER has been negotiated but not MRG_RXBUF, it gets re-enabled.
Will move ARM force action behind normal selection, thus can satisfy ARM.
I can change when applying.
Thanks,
Maxime
Thanks,
Marvin
}
- if (rx_offloads & (DEV_RX_OFFLOAD_UDP_CKSUM |
- DEV_RX_OFFLOAD_TCP_CKSUM))
- hw->use_simple_rx = 0;
-
return 0;
}
