DOKK / manpages / debian 12 / libibverbs-dev / ibv_query_qp_data_in_order.3.en
ibv_query_qp_data_in_order(3) Libibverbs Programmer’s Manual ibv_query_qp_data_in_order(3)

ibv_query_qp_data_in_order - check if qp data is guaranteed to be in order.

#include <infiniband/verbs.h>
int ibv_query_qp_data_in_order(struct ibv_qp *qp, enum ibv_wr_opcode op, uint32_t flags);

ibv_query_qp_data_in_order() Checks whether WQE data is guaranteed to be written in-order, and thus reader may poll for data instead of poll for completion. This function indicates data is written in-order within each WQE, but cannot be used to determine ordering between separate WQEs. This function describes ordering at the receiving side of the QP, not the sending side.

The local queue pair (QP) to query.
    
The operation type to query about. Different operation types may write data in a different order.
For RDMA read operations: describes ordering of RDMA reads posted on this local QP. For RDMA write operations: describes ordering of remote RDMA writes being done into this local QP. For RDMA send operations: describes ordering of remote RDMA sends being done into this local QP. This function should not be used to determine ordering of other operation types.
Extra field for future input. For now must be 0.

ibv_query_qp_data_in_order() Returns 1 if the data is guaranteed to be written in-order, 0 otherwise.

Return value is valid only when the data is read by the CPU and relaxed ordering MR is not the target of the transfer.

ibv_query_qp(3)

Patrisious Haddad <phaddad@nvidia.com>

Yochai Cohen <yochai@nvidia.com>

2020-3-3 libibverbs