NAME

       mlx5dv_map_ah_to_qp  -  Map the destination path information in address handle (AH) to the
       information extracted from the qp.

SYNOPSIS

              #include <infiniband/mlx5dv.h>

              int mlx5dv_map_ah_to_qp(struct ibv_ah *ah, uint32_t qp_num);

DESCRIPTION

       This API maps the destination path information in address handle (ah) to  the  information
       extracted from the qp (e.g. congestion control from ECE).

       This  API serves as an enhancement to DC and UD QPs to achieve better performance by using
       per-address congestion control (CC) algorithms, enabling DC/UD  QPs  to  use  multiple  CC
       algorithms in the same datacenter.

       The  mapping  created  by  this  API  is  implicitly  destroyed when the address handle is
       destroyed.  It is not affected by the destruction of QP qp_num.

       A duplicate mapping to the same address handle is ignored.  As this API is just a hint for
       the  hardware  in  this  case it would do nothing and return success regardless of the new
       qp_num ECE.

       The function must be called  after  ECE  negotiation/preconfiguration  was  done  by  some
       external means.

ARGUMENTS

       ah     The target’s address handle.

       qp_num The  initiator  QP  from which congestion control information is extracted from its
              ECE.

RETURN VALUE

       Upon success, returns 0; Upon failure, the value of errno is returned.

SEE ALSO

       rdma_cm(7), rdma_get_remote_ece(3), ibv_query_ece(3), ibv_set_ece(3)

AUTHOR

       Yochai Cohen <yochai@nvidia.com>

       Patrisious Haddad <phaddad@nvidia.com>

                                                                           mlx5dv_map_ah_to_qp(3)