Re: [PATCH v5 2/3] RDMA/rxe: add SENT/RCVD bytes

From: Zhu Yanjun

Date: Sat Apr 11 2026 - 14:57:16 EST


在 2026/4/11 0:24, zhenwei pi 写道:


On 4/11/26 09:45, Zhu Yanjun wrote:

在 2026/4/10 15:37, yanjun.zhu 写道:
On 4/7/26 5:09 PM, zhenwei pi wrote:
There is a lack of sent/received counter in bytes.

Signed-off-by: zhenwei pi <zhenwei.pi@xxxxxxxxx>
---
  drivers/infiniband/sw/rxe/rxe_hw_counters.c | 2 ++
  drivers/infiniband/sw/rxe/rxe_hw_counters.h | 2 ++
  drivers/infiniband/sw/rxe/rxe_net.c         | 2 ++
  drivers/infiniband/sw/rxe/rxe_recv.c        | 2 ++
  drivers/infiniband/sw/rxe/rxe_verbs.h       | 6 ++++++
  5 files changed, 14 insertions(+)

diff --git a/drivers/infiniband/sw/rxe/rxe_hw_counters.c b/drivers/ infiniband/sw/rxe/rxe_hw_counters.c
index 437917a7d8f2..17edaa9a9b9b 100644
--- a/drivers/infiniband/sw/rxe/rxe_hw_counters.c
+++ b/drivers/infiniband/sw/rxe/rxe_hw_counters.c
@@ -22,6 +22,8 @@ static const struct rdma_stat_desc rxe_counter_descs[] = {
      [RXE_CNT_LINK_DOWNED].name         =  "link_downed",
      [RXE_CNT_RDMA_SEND].name           =  "rdma_sends",
      [RXE_CNT_RDMA_RECV].name           =  "rdma_recvs",
+    [RXE_CNT_SENT_BYTES].name          =  "sent_bytes",
+    [RXE_CNT_RCVD_BYTES].name          =  "rcvd_bytes",
  };
    int rxe_ib_get_hw_stats(struct ib_device *ibdev,
diff --git a/drivers/infiniband/sw/rxe/rxe_hw_counters.h b/drivers/ infiniband/sw/rxe/rxe_hw_counters.h
index 051f9e1c3852..01b355103cbc 100644
--- a/drivers/infiniband/sw/rxe/rxe_hw_counters.h
+++ b/drivers/infiniband/sw/rxe/rxe_hw_counters.h
@@ -26,6 +26,8 @@ enum rxe_counters {
      RXE_CNT_LINK_DOWNED,
      RXE_CNT_RDMA_SEND,
      RXE_CNT_RDMA_RECV,
+    RXE_CNT_SENT_BYTES,
+    RXE_CNT_RCVD_BYTES,
      RXE_NUM_OF_COUNTERS
  };
  diff --git a/drivers/infiniband/sw/rxe/rxe_net.c b/drivers/ infiniband/sw/rxe/rxe_net.c
index 6621d01ac32d..86660031ffa2 100644
--- a/drivers/infiniband/sw/rxe/rxe_net.c
+++ b/drivers/infiniband/sw/rxe/rxe_net.c
@@ -503,6 +503,7 @@ int rxe_xmit_packet(struct rxe_qp *qp, struct rxe_pkt_info *pkt,
      int err;
      int is_request = pkt->mask & RXE_REQ_MASK;
      struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
+    unsigned int skblen = skb->len;
      unsigned long flags;
        spin_lock_irqsave(&qp->state_lock, flags);
@@ -526,6 +527,7 @@ int rxe_xmit_packet(struct rxe_qp *qp, struct rxe_pkt_info *pkt,
      }
        rxe_counter_inc(rxe, RXE_CNT_SENT_PKTS);
+    rxe_counter_add(rxe, RXE_CNT_SENT_BYTES, skblen);
      goto done;
    drop:
diff --git a/drivers/infiniband/sw/rxe/rxe_recv.c b/drivers/ infiniband/sw/rxe/rxe_recv.c
index 5861e4244049..e7bab89e7d8d 100644
--- a/drivers/infiniband/sw/rxe/rxe_recv.c
+++ b/drivers/infiniband/sw/rxe/rxe_recv.c
@@ -318,6 +318,7 @@ void rxe_rcv(struct sk_buff *skb)
      int err;
      struct rxe_pkt_info *pkt = SKB_TO_PKT(skb);
      struct rxe_dev *rxe = pkt->rxe;
+    unsigned int skblen = skb->len - skb_network_offset(skb);
        if (unlikely(skb->len < RXE_BTH_BYTES))
          goto drop;
@@ -341,6 +342,7 @@ void rxe_rcv(struct sk_buff *skb)
      if (unlikely(err))
          goto drop;
  +    rxe_counter_add(rxe, RXE_CNT_RCVD_BYTES, skblen);
      rxe_counter_inc(rxe, RXE_CNT_RCVD_PKTS);
        if (unlikely(bth_qpn(pkt) == IB_MULTICAST_QPN))

int rxe_xmit_packet(struct rxe_qp *qp, struct rxe_pkt_info *pkt,
                    struct sk_buff *skb)
{
        int err;
        int is_request = pkt->mask & RXE_REQ_MASK;
        struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
        unsigned long flags;

skb->len is printed here, that is len1
...
        if (pkt->mask & RXE_LOOPBACK_MASK)
                err = rxe_loopback(skb, pkt);
        else
                err = rxe_send(skb, pkt);
...
}

In the following function

static int rxe_loopback(struct sk_buff *skb, struct rxe_pkt_info *pkt)
{
...
        if (skb->protocol == htons(ETH_P_IP))
                skb_pull(skb, sizeof(struct iphdr));
        else
                skb_pull(skb, sizeof(struct ipv6hdr));

...
        /* remove udp header */
        skb_pull(skb, sizeof(struct udphdr));

print skb->len here, that is len2

        rxe_rcv(skb);

...
}

Does len1 equal to len2?

I have made tests. The difference between len1 and len2 is 28.

It should be the total of ipv4 header + udp header because I use ipv4 address to make tests.

I am not sure if the bytes of recv data should equal to the bytes of xmit data.


Zhu Yanjun


Yes, I got the same result of 28 bytes difference during v4 version. So I try to use such logic to recalculate the length:

+    unsigned int skblen = skb->len + sizeof(struct udphdr);
...
+    if (skb->protocol == htons(ETH_P_IP))
+        skblen += sizeof(struct iphdr);
+    else if (skb->protocol == htons(ETH_P_IPV6))
+        skblen += sizeof(struct ipv6hdr);
+    rxe_counter_add(rxe, RXE_CNT_RCVD_BYTES, skblen);

then use 'unsigned int skblen = skb->len - skb_network_offset(skb);' in v5.

Thanks. Not necessary to use this 'unsigned int skblen = skb->len - skb_network_offset(skb);'.

The above udphdr and iphdr/ip6hdr should be OK.

Thanks a lot.
Zhu Yanjun



If not, the transmitted length appears to differ from the received length when using loopback.

I am not sure whether this is expected behavior.

The same observation also applies to the non-loopback case.

Zhu Yanjun

diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.h b/drivers/ infiniband/sw/rxe/rxe_verbs.h
index e800545d1046..0f5ffd94643f 100644
--- a/drivers/infiniband/sw/rxe/rxe_verbs.h
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.h
@@ -455,6 +455,12 @@ static inline void rxe_counter_inc(struct rxe_dev *rxe, enum rxe_counters index)
      atomic64_inc(&rxe->stats_counters[index]);
  }
  +static inline void rxe_counter_add(struct rxe_dev *rxe, enum rxe_counters index,
+                   s64 val)
+{
+    atomic64_add(val, &rxe->stats_counters[index]);
+}
+
  static inline struct rxe_dev *to_rdev(struct ib_device *dev)
  {
      return dev ? container_of(dev, struct rxe_dev, ib_dev) : NULL;