ibv_poll_cq - poll a completion queue (CQ)
#include <infiniband/verbs.h> int ibv_poll_cq(struct ibv_cq *cq, int num_entries, struct ibv_wc *wc);
Libibverbs Programmer's Manual IBV_POLL_CQ(3) NAME ibv_poll_cq - poll a completion queue (CQ) SYNOPSIS #include <infiniband/verbs.h> int ibv_poll_cq(struct ibv_cq *cq, int num_entries, struct ibv_wc *wc); DESCRIPTION ibv_poll_cq() polls the CQ cq for work completions and returns the first num_entries (or all available completions if the CQ contains fewer than this number) in the array wc. The argument wc is a pointer to an array of ibv_wc structs, as defined in <infiniband/verbs.h>. struct ibv_wc { uint64_t wr_id; /* ID of the completed Work Request (WR) */ enum ibv_wc_status status; /* Status of the operation */ enum ibv_wc_opcode opcode; /* Operation type specified in the completed WR */ uint32_t vendor_err; /* Vendor error syndrome */ uint32_t byte_len; /* Number of bytes transferred */ uint32_t imm_data; /* Immediate data (in network byte order) */ uint32_t qp_num; /* Local QP number of completed WR */ uint32_t src_qp; /* Source QP number (remote QP number) of completed WR (valid only for UD QPs) */ int wc_flags; /* Flags of the completed WR */ uint16_t pkey_index; /* P_Key index (valid only for GSI QPs) */ uint16_t slid; /* Source LID */ uint8_t sl; /* Service Level */ uint8_t dlid_path_bits; /* DLID path bits (not applicable for multicast messages) */ }; The attribute wc_flags describes the properties of the work completion. It is either 0 or the bitwise OR of one or more of the following flags: IBV_WC_GRH GRH is present (valid only for UD QPs) IBV_WC_WITH_IMM Immediate data value is valid Not all wc attributes are always valid. If the completion status is other than IBV_WC_SUCCESS, only the following attributes are valid: wr_id, status, qp_num, and vendor_err. RETURN VALUE On success, ibv_poll_cq() returns a non-negative value equal to the number of completions found. On failure, a negative value is returned. ATTRIBUTES See attributes(7) for descriptions of the following attributes: +---------------+-----------------------+ |ATTRIBUTE TYPE | ATTRIBUTE VALUE | +---------------+-----------------------+ |Availability | network/open-fabrics | +---------------+-----------------------+ |Stability | Pass-through volatile | +---------------+-----------------------+ NOTES Each polled completion is removed from the CQ and cannot be returned to it. The user should consume work completions at a rate that prevents CQ overrun from occurrence. In case of a CQ overrun, the async event IBV_EVENT_CQ_ERR will be triggered, and the CQ cannot be used. Source code for open source software components in Oracle Solaris can be found at https://www.oracle.com/downloads/opensource/solaris-source- code-downloads.html. This software was built from source available at https://github.com/oracle/solaris-userland. The original community source was downloaded from ['https://www.openfabrics.org/down- loads/ibutils/ibutils-1.5.7-0.2.gbd7e502.tar.gz', 'https://www.openfab- rics.org/downloads/libibverbs/libibverbs-1.1.8.tar.gz', 'https://www.openfabrics.org/downloads/libmlx4/libmlx4-1.0.6.tar.gz', 'https://www.openfabrics.org/downloads/libsdp/lib- sdp-1.1.108-0.15.gd7fdb72.tar.gz', 'https://www.openfabrics.org/down- loads/management/infiniband-diags-1.6.5.tar.gz', 'https://www.openfab- rics.org/downloads/management/libibmad-1.3.12.tar.gz', 'https://www.openfabrics.org/downloads/management/libibu- mad-1.3.10.2.tar.gz', 'https://www.openfabrics.org/downloads/manage- ment/opensm-3.3.19.tar.gz', 'https://www.openfabrics.org/down- loads/perftest/perftest-1.3.0-0.42.gf350d3d.tar.gz', 'https://www.open- fabrics.org/downloads/qperf/qperf-0.4.9.tar.gz', 'https://www.openfab- rics.org/downloads/rdmacm/librdmacm-1.0.21.tar.gz', 'https://www.open- fabrics.org/downloads/rds-tools/rds-tools-2.0.4.tar.gz']. Further information about this software can be found on the open source community website at http://www.openfabrics.org/. SEE ALSO ibv_post_send(3), ibv_post_recv(3) AUTHORS Dotan Barak <dotanba@gmail.com> libibverbs 2006-10-31 IBV_POLL_CQ(3)