在 2024/8/23 16:23, zhenwei pi 写道:
On 8/23/24 13:56, Zhu Yanjun wrote:
在 2024/8/23 10:30, zhenwei pi 写道:
On 8/22/24 20:36, Jason Gunthorpe wrote:
> On Thu, Aug 22, 2024 at 07:59:32PM +0800, Zhu Yanjun wrote:
>> 在 2024/8/22 14:52, zhenwei pi 写道:
>>> Use 'sizeof(union rdma_network_hdr)' instead of hard code GRH
length
>>> for GSI and UD.
>>>
>>> Signed-off-by: zhenwei pi
>>> ---
>>> drivers/infiniband/sw/rxe/rxe_resp.c | 2 +-
>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/
infiniband/sw/rxe/rxe_resp.c
>>> index 6596a85723c9..bf8f4bc8c5c8 100644
>>> --- a/drivers/infiniband/sw/rxe/rxe_resp.c
>>> +++ b/drivers/infiniband/sw/rxe/rxe_resp.c
>>> @@ -351,7 +351,7 @@ static enum resp_states
rxe_resp_check_length(struct rxe_qp *qp,
>>> for (i = 0; i < qp->resp.wqe->dma.num_sge; i++)
>>> recv_buffer_len += qp->resp.wqe->dma.sge[i].length;
>>> - if (payload + 40 > recv_buffer_len) {
>>> + if (payload + sizeof(union rdma_network_hdr) > recv_buffer_len) {
>>
>> The definition of union rdma_network_hdr is as below
>>
>> 797 union rdma_network_hdr {
>> 798 struct ib_grh ibgrh;
>> 799 struct {
>> 800 /* The IB spec states that if it's IPv4, the header
>> 801 * is located in the last 20 bytes of the header.
>> 802 */
>> 803 u8 reserved[20];
>> 804 struct iphdr roce4grh;
>> 805 };
>> 806 };
>>
>> The length is 40 byte.
>
> This looks like the right struct to me if this is talking about the
> special 40 byte blob that is placed in front of UD verbs completions.
>
> Jason
Yes, this is the front part(40 bytes) of UD/GSI verbs completion.
When running, you can print the value of the front part (40 bytes) of
UD/GSI to confirm that these 40 bytes are the union rdma_network_hdr.
If these 40 bytes are the union rdma_network_hdr,
Reviewed-by: Zhu Yanjun <yanjun.zhu@xxxxxxxxx>
Best Regards,
Zhu Yanjun
Hi Yanjun,
I test on mlx-cx5 by command: ibv_ud_pingpong -d mlx5_2 -g 3 -r 1 -n 1
Dump the front 64 bytes:
00000000000000000000000000000000000000004502043436f340000111448c
0a0b73120a0b73107b7b7b7b7b7b7b7b7b7b7b7b7b7b7b7b7b7b7b7b7b7b7b7b
Byte[0, 20) (rdma_network_hdr::reserved[20]) are filled by zero,
byte[20,40) (rdma_network_hdr::roce4grh) are filled by IPv4 header.
Got it. Thanks a lot.
I am fine with your commit.
Best Regards,
Zhu Yanjun
--
zhenwei pi
--
Best Regards,
Yanjun.Zhu
