[openib-general] modifying queue pair attributes - librdmacm

[vishal]

Hi,

    I have a simple program running in client-server mode using
librdmacm. I was wanting to be able to change the path_mtu attribute of
the queue pairs in the program. Following is the piece of code which
tries to do it:-

 struct ibv_qp_attr attr = {
                .path_mtu               = IBV_MTU_2048
        };
        if (ibv_modify_qp(cb->qp, &attr, IBV_QP_PATH_MTU) ){
                fprintf(stderr, "Failed to modify QP\n");
                fprintf(stderr, "%s \n\n", strerror(errno) );
                return 1;
        }


And, it fails to do the job (The error string comes up with "Invalid
argument".)! I can't find any function in librdmacm which allows us to
modify the queue pair attributes. What am I doing wrong ?

Thanks!

Vishal