ibv_query_comp_cntr_caps(3)                     Libibverbs Programmer's Manual

NAME
       ibv_query_comp_cntr_caps - Query completion counter capabilities

SYNOPSIS
              #include <infiniband/verbs.h>

              int ibv_query_comp_cntr_caps(struct ibv_context *context,
                                           struct ibv_comp_cntr_caps *caps);

DESCRIPTION
       ibv_query_comp_cntr_caps() queries the completion counter capabilities
       of the RDMA device associated with context.

ARGUMENTS
   ibv_comp_cntr_caps
              struct ibv_comp_cntr_caps {
                  uint64_t max_value;
                  uint32_t max_counters;
                  uint32_t supported_qp_attach_ops;
              };

       max_value
              The maximum value a completion counter can hold.  A subsequent
              increment that would exceed this value wraps the counter to
              zero.

       max_counters
              The maximum number of completion counters that can be created on
              this device.

       supported_qp_attach_ops
              A bitmask of ibv_qp_attach_comp_cntr_op values indicating which
              attach operations are supported by the device.  See
              ibv_qp_attach_comp_cntr(3) for the list of operations.

RETURN VALUE
       ibv_query_comp_cntr_caps() returns 0 on success, or the value of errno
       on failure (which indicates the failure reason).

ERRORS
       ENOTSUP
              Completion counters are not supported on this device.

SEE ALSO
       ibv_create_comp_cntr(3), ibv_qp_attach_comp_cntr(3)

AUTHORS
       Michael Margolin <mrgolin@amazon.com>

libibverbs                        2026-07-17       ibv_query_comp_cntr_caps(3)