Reduce host CPU overhead of Tx packet processing:
* Use local variables inside per packet loop instead of fields in structs.
* Factor book keeping and conditionals out of the per packet loop where
possible.
* Post buffers to the nic at a maximum of every 64 packets
Signed-off-by: Nelson Escobar <neescoba at cisco.com>
Signed-off-by: John Daley <johndale at cisco.com>
---
drivers/net/enic/base/vnic_wq.h | 1 +
drivers/net/enic/enic_res.h | 2 +-
drivers/net/enic/enic_rxtx.c | 167 +++++++++++++++++++---------------------
3 files changed, 83 insertions(+), 87 deletions(-)
diff --git a/drivers/net/enic/base/vnic_wq.h b/drivers/net/enic/base/vnic_wq.h
index 689b81c..7a66813 100644
--- a/drivers/net/enic/base/vnic_wq.h
+++ b/drivers/net/enic/base/vnic_wq.h
@@ -67,6 +67,7 @@ struct vnic_wq_ctrl {
/* 16 bytes */
struct vnic_wq_buf {
+ struct rte_mempool *pool;
void *mb;
};
diff --git a/drivers/net/enic/enic_res.h b/drivers/net/enic/enic_res.h
index 955db71..3c8e303 100644
--- a/drivers/net/enic/enic_res.h
+++ b/drivers/net/enic/enic_res.h
@@ -53,7 +53,7 @@
#define ENIC_NON_TSO_MAX_DESC 16
#define ENIC_DEFAULT_RX_FREE_THRESH 32
-#define ENIC_TX_POST_THRESH (ENIC_MIN_WQ_DESCS / 2)
+#define ENIC_TX_XMIT_MAX 64
#define ENIC_SETTING(enic, f) ((enic->config.flags & VENETF_##f) ? 1 : 0)
diff --git a/drivers/net/enic/enic_rxtx.c b/drivers/net/enic/enic_rxtx.c
index ec8d90a..ba15670 100644
--- a/drivers/net/enic/enic_rxtx.c
+++ b/drivers/net/enic/enic_rxtx.c
@@ -374,114 +374,109 @@ unsigned int enic_cleanup_wq(__rte_unused struct enic
*enic, struct vnic_wq *wq)
return 0;
}
-void enic_post_wq_index(struct vnic_wq *wq)
-{
- enic_vnic_post_wq_index(wq);
-}
-
-void enic_send_pkt(struct enic *enic, struct vnic_wq *wq,
- struct rte_mbuf *tx_pkt, unsigned short len,
- uint8_t sop, uint8_t eop, uint8_t cq_entry,
- uint16_t ol_flags, uint16_t vlan_tag)
-{
- struct wq_enet_desc *desc, *descs;
- uint16_t mss = 0;
- uint8_t vlan_tag_insert = 0;
- uint64_t bus_addr = (dma_addr_t)
- (tx_pkt->buf_physaddr + tx_pkt->data_off);
-
- descs = (struct wq_enet_desc *)wq->ring.descs;
- desc = descs + wq->head_idx;
-
- if (sop) {
- if (ol_flags & PKT_TX_VLAN_PKT)
- vlan_tag_insert = 1;
-
- if (enic->hw_ip_checksum) {
- if (ol_flags & PKT_TX_IP_CKSUM)
- mss |= ENIC_CALC_IP_CKSUM;
-
- if (ol_flags & PKT_TX_TCP_UDP_CKSUM)
- mss |= ENIC_CALC_TCP_UDP_CKSUM;
- }
- }
-
- wq_enet_desc_enc(desc,
- bus_addr,
- len,
- mss,
- 0 /* header_length */,
- 0 /* offload_mode WQ_ENET_OFFLOAD_MODE_CSUM */,
- eop,
- cq_entry,
- 0 /* fcoe_encap */,
- vlan_tag_insert,
- vlan_tag,
- 0 /* loopback */);
-
- enic_vnic_post_wq(wq, (void *)tx_pkt, cq_entry);
-}
-
uint16_t enic_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
uint16_t nb_pkts)
{
uint16_t index;
- unsigned int frags;
- unsigned int pkt_len;
- unsigned int seg_len;
- unsigned int inc_len;
+ unsigned int pkt_len, data_len;
unsigned int nb_segs;
- struct rte_mbuf *tx_pkt, *next_tx_pkt;
+ struct rte_mbuf *tx_pkt;
struct vnic_wq *wq = (struct vnic_wq *)tx_queue;
struct enic *enic = vnic_dev_priv(wq->vdev);
unsigned short vlan_id;
unsigned short ol_flags;
- uint8_t last_seg, eop;
- unsigned int host_tx_descs = 0;
+ unsigned int wq_desc_avail;
+ int head_idx;
+ struct vnic_wq_buf *buf;
+ unsigned int hw_ip_cksum_enabled;
+ unsigned int desc_count;
+ struct wq_enet_desc *descs, *desc_p, desc_tmp;
+ uint16_t mss;
+ uint8_t vlan_tag_insert;
+ uint8_t eop;
+ uint64_t bus_addr;
+ enic_cleanup_wq(enic, wq);
+ wq_desc_avail = vnic_wq_desc_avail(wq);
+ head_idx = wq->head_idx;
+ desc_count = wq->ring.desc_count;
+
+ nb_pkts = RTE_MIN(nb_pkts, ENIC_TX_XMIT_MAX);
+
+ hw_ip_cksum_enabled = enic->hw_ip_checksum;
for (index = 0; index < nb_pkts; index++) {
tx_pkt = *tx_pkts++;
- inc_len = 0;
nb_segs = tx_pkt->nb_segs;
- if (nb_segs > vnic_wq_desc_avail(wq)) {
+ if (nb_segs > wq_desc_avail) {
if (index > 0)
- enic_post_wq_index(wq);
-
- /* wq cleanup and try again */
- if (!enic_cleanup_wq(enic, wq) ||
- (nb_segs > vnic_wq_desc_avail(wq))) {
- return index;
- }
+ goto post;
+ goto done;
}
pkt_len = tx_pkt->pkt_len;
+ data_len = tx_pkt->data_len;
vlan_id = tx_pkt->vlan_tci;
ol_flags = tx_pkt->ol_flags;
- for (frags = 0; inc_len < pkt_len; frags++) {
- if (!tx_pkt)
- break;
- next_tx_pkt = tx_pkt->next;
- seg_len = tx_pkt->data_len;
- inc_len += seg_len;
-
- host_tx_descs++;
- last_seg = 0;
- eop = 0;
- if ((pkt_len == inc_len) || !next_tx_pkt) {
- eop = 1;
- /* post if last packet in batch or > thresh */
- if ((index == (nb_pkts - 1)) ||
- (host_tx_descs > ENIC_TX_POST_THRESH)) {
- last_seg = 1;
- host_tx_descs = 0;
- }
+
+ mss = 0;
+ vlan_tag_insert = 0;
+ bus_addr = (dma_addr_t)
+ (tx_pkt->buf_physaddr + tx_pkt->data_off);
+
+ descs = (struct wq_enet_desc *)wq->ring.descs;
+ desc_p = descs + head_idx;
+
+ eop = (data_len == pkt_len);
+
+ if (ol_flags & PKT_TX_VLAN_PKT)
+ vlan_tag_insert = 1;
+
+ if (hw_ip_cksum_enabled && (ol_flags & PKT_TX_IP_CKSUM))
+ mss |= ENIC_CALC_IP_CKSUM;
+
+ if (hw_ip_cksum_enabled && (ol_flags & PKT_TX_TCP_UDP_CKSUM))
+ mss |= ENIC_CALC_TCP_UDP_CKSUM;
+
+ wq_enet_desc_enc(&desc_tmp, bus_addr, data_len, mss, 0, 0, eop,
+ eop, 0, vlan_tag_insert, vlan_id, 0);
+
+ *desc_p = desc_tmp;
+ buf = &wq->bufs[head_idx];
+ buf->mb = (void *)tx_pkt;
+ head_idx = enic_ring_incr(desc_count, head_idx);
+ wq_desc_avail--;
+
+ if (!eop) {
+ for (tx_pkt = tx_pkt->next; tx_pkt; tx_pkt =
+ tx_pkt->next) {
+ data_len = tx_pkt->data_len;
+
+ if (tx_pkt->next == NULL)
+ eop = 1;
+ desc_p = descs + head_idx;
+ bus_addr = (dma_addr_t)(tx_pkt->buf_physaddr
+ + tx_pkt->data_off);
+ wq_enet_desc_enc((struct wq_enet_desc *)
+ &desc_tmp, bus_addr, data_len,
+ mss, 0, 0, eop, eop, 0,
+ vlan_tag_insert, vlan_id, 0);
+
+ *desc_p = desc_tmp;
+ buf = &wq->bufs[head_idx];
+ buf->mb = (void *)tx_pkt;
+ head_idx = enic_ring_incr(desc_count, head_idx);
+ wq_desc_avail--;
}
- enic_send_pkt(enic, wq, tx_pkt, (unsigned short)seg_len,
- !frags, eop, last_seg, ol_flags, vlan_id);
- tx_pkt = next_tx_pkt;
}
}
+ post:
+ rte_wmb();
+ iowrite32(head_idx, &wq->ctrl->posted_index);
+ done:
+ wq->ring.desc_avail = wq_desc_avail;
+ wq->head_idx = head_idx;
- enic_cleanup_wq(enic, wq);
return index;
}
+
+
--
2.7.0
