Re: [PATCH 1/1] IB: rxe: replace av->network_type with skb->protocol

[Yanjun Zhu <yanjun.zhu@xxxxxxxxxx>]

ping

On 2019/2/24 19:26, Zhu Yanjun wrote:
> In the function rxe_init_packet, based on av->network_type,
> skb->protocol is set to ipv4 or ipv6. The functions rxe_prepare
> and rxe_send are called after the functin rxe_init_packet.
> So in these functions, av->network_type can be replaced with
> skb->protocol.
> The functions are in the xmit fast path. So with skb->protocol,
> the performance will be better.
>
> Signed-off-by: Zhu Yanjun <yanjun.zhu@xxxxxxxxxx>
> ---
>   drivers/infiniband/sw/rxe/rxe_net.c | 26 +++++++++++---------------
>   1 file changed, 11 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/infiniband/sw/rxe/rxe_net.c b/drivers/infiniband/sw/rxe/rxe_net.c
> index 8fd03ae..edac208 100644
> --- a/drivers/infiniband/sw/rxe/rxe_net.c
> +++ b/drivers/infiniband/sw/rxe/rxe_net.c
> @@ -368,13 +368,13 @@ static void prepare_ipv6_hdr(struct dst_entry *dst, struct sk_buff *skb,
>   	ip6h->payload_len = htons(skb->len - sizeof(*ip6h));
>   }
>   
> -static int prepare4(struct rxe_pkt_info *pkt, struct sk_buff *skb,
> -		    struct rxe_av *av)
> +static int prepare4(struct rxe_pkt_info *pkt, struct sk_buff *skb)
>   {
>   	struct rxe_qp *qp = pkt->qp;
>   	struct dst_entry *dst;
>   	bool xnet = false;
>   	__be16 df = htons(IP_DF);
> +	struct rxe_av *av = rxe_get_av(pkt);
>   	struct in_addr *saddr = &av->sgid_addr._sockaddr_in.sin_addr;
>   	struct in_addr *daddr = &av->dgid_addr._sockaddr_in.sin_addr;
>   
> @@ -397,11 +397,11 @@ static int prepare4(struct rxe_pkt_info *pkt, struct sk_buff *skb,
>   	return 0;
>   }
>   
> -static int prepare6(struct rxe_pkt_info *pkt, struct sk_buff *skb,
> -		    struct rxe_av *av)
> +static int prepare6(struct rxe_pkt_info *pkt, struct sk_buff *skb)
>   {
>   	struct rxe_qp *qp = pkt->qp;
>   	struct dst_entry *dst;
> +	struct rxe_av *av = rxe_get_av(pkt);
>   	struct in6_addr *saddr = &av->sgid_addr._sockaddr_in6.sin6_addr;
>   	struct in6_addr *daddr = &av->dgid_addr._sockaddr_in6.sin6_addr;
>   
> @@ -428,12 +428,11 @@ static int prepare6(struct rxe_pkt_info *pkt, struct sk_buff *skb,
>   int rxe_prepare(struct rxe_pkt_info *pkt, struct sk_buff *skb, u32 *crc)
>   {
>   	int err = 0;
> -	struct rxe_av *av = rxe_get_av(pkt);
>   
> -	if (av->network_type == RDMA_NETWORK_IPV4)
> -		err = prepare4(pkt, skb, av);
> -	else if (av->network_type == RDMA_NETWORK_IPV6)
> -		err = prepare6(pkt, skb, av);
> +	if (skb->protocol == htons(ETH_P_IP))
> +		err = prepare4(pkt, skb);
> +	else if (skb->protocol == htons(ETH_P_IPV6))
> +		err = prepare6(pkt, skb);
>   
>   	*crc = rxe_icrc_hdr(pkt, skb);
>   
> @@ -455,23 +454,20 @@ static void rxe_skb_tx_dtor(struct sk_buff *skb)
>   
>   int rxe_send(struct rxe_pkt_info *pkt, struct sk_buff *skb)
>   {
> -	struct rxe_av *av;
>   	int err;
>   
> -	av = rxe_get_av(pkt);
> -
>   	skb->destructor = rxe_skb_tx_dtor;
>   	skb->sk = pkt->qp->sk->sk;
>   
>   	rxe_add_ref(pkt->qp);
>   	atomic_inc(&pkt->qp->skb_out);
>   
> -	if (av->network_type == RDMA_NETWORK_IPV4) {
> +	if (skb->protocol == htons(ETH_P_IP)) {
>   		err = ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
> -	} else if (av->network_type == RDMA_NETWORK_IPV6) {
> +	} else if (skb->protocol == htons(ETH_P_IPV6)) {
>   		err = ip6_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
>   	} else {
> -		pr_err("Unknown layer 3 protocol: %d\n", av->network_type);
> +		pr_err("Unknown layer 3 protocol: %d\n", skb->protocol);
>   		atomic_dec(&pkt->qp->skb_out);
>   		rxe_drop_ref(pkt->qp);
>   		kfree_skb(skb);