/**
 * Copyright (c) 2021 Mellanox Technologies. All rights reserved.
 * $COPYRIGHT$
 *
 * Additional copyrights may follow
 *
 */

#include "coll_ucc_common.h"

static inline ucc_status_t mca_coll_ucc_reduce_init(const void *sbuf, void *rbuf, int count,
                                                    struct ompi_datatype_t *dtype,
                                                    struct ompi_op_t *op, int root,
                                                    mca_coll_ucc_module_t *ucc_module,
                                                    ucc_coll_req_h *req,
                                                    mca_coll_ucc_req_t *coll_req)
{
    ucc_datatype_t         ucc_dt;
    ucc_reduction_op_t     ucc_op;

    ucc_dt = ompi_dtype_to_ucc_dtype(dtype);
    ucc_op = ompi_op_to_ucc_op(op);
    if (OPAL_UNLIKELY(COLL_UCC_DT_UNSUPPORTED == ucc_dt)) {
        UCC_VERBOSE(5, "ompi_datatype is not supported: dtype = %s",
                    dtype->super.name);
        goto fallback;
    }
    if (OPAL_UNLIKELY(COLL_UCC_OP_UNSUPPORTED == ucc_op)) {
        UCC_VERBOSE(5, "ompi_op is not supported: op = %s",
                    op->o_name);
        goto fallback;
    }
    ucc_coll_args_t coll = {
        .mask      = 0,
        .flags     = 0,
        .coll_type = UCC_COLL_TYPE_REDUCE,
        .root = root,
        .src.info = {
            .buffer   = (void*)sbuf,
            .count    = count,
            .datatype = ucc_dt,
            .mem_type = UCC_MEMORY_TYPE_UNKNOWN
        },
        .dst.info = {
            .buffer   = rbuf,
            .count    = count,
            .datatype = ucc_dt,
            .mem_type = UCC_MEMORY_TYPE_UNKNOWN
        },
        .op = ucc_op,
    };
    if (MPI_IN_PLACE == sbuf) {
        coll.mask |= UCC_COLL_ARGS_FIELD_FLAGS;
        coll.flags = UCC_COLL_ARGS_FLAG_IN_PLACE;
    }
    COLL_UCC_REQ_INIT(coll_req, req, coll, ucc_module);
    return UCC_OK;
fallback:
    return UCC_ERR_NOT_SUPPORTED;
}

int mca_coll_ucc_reduce(const void *sbuf, void* rbuf, int count,
                        struct ompi_datatype_t *dtype,
                        struct ompi_op_t *op, int root,
                        struct ompi_communicator_t *comm,
                        struct mca_coll_base_module_2_4_0_t *module)
{
    mca_coll_ucc_module_t *ucc_module = (mca_coll_ucc_module_t*)module;
    ucc_coll_req_h         req;

    UCC_VERBOSE(3, "running ucc reduce");
    COLL_UCC_CHECK(mca_coll_ucc_reduce_init(sbuf, rbuf, count, dtype, op,
                                            root, ucc_module, &req, NULL));
    COLL_UCC_POST_AND_CHECK(req);
    COLL_UCC_CHECK(coll_ucc_req_wait(req));
    return OMPI_SUCCESS;
fallback:
    UCC_VERBOSE(3, "running fallback reduce");
    return ucc_module->previous_reduce(sbuf, rbuf, count, dtype, op, root,
                                       comm, ucc_module->previous_reduce_module);
}

int mca_coll_ucc_ireduce(const void *sbuf, void* rbuf, int count,
                         struct ompi_datatype_t *dtype,
                         struct ompi_op_t *op, int root,
                         struct ompi_communicator_t *comm,
                         ompi_request_t** request,
                         struct mca_coll_base_module_2_4_0_t *module)
{
    mca_coll_ucc_module_t *ucc_module = (mca_coll_ucc_module_t*)module;
    ucc_coll_req_h         req;
    mca_coll_ucc_req_t    *coll_req = NULL;

    UCC_VERBOSE(3, "running ucc ireduce");
    COLL_UCC_GET_REQ(coll_req);
    COLL_UCC_CHECK(mca_coll_ucc_reduce_init(sbuf, rbuf, count, dtype, op, root,
                                            ucc_module, &req, coll_req));
    COLL_UCC_POST_AND_CHECK(req);
    *request = &coll_req->super;
    return OMPI_SUCCESS;
fallback:
    UCC_VERBOSE(3, "running fallback ireduce");
    if (coll_req) {
        mca_coll_ucc_req_free((ompi_request_t **)&coll_req);
    }
    return ucc_module->previous_ireduce(sbuf, rbuf, count, dtype, op, root,
                                        comm, request, ucc_module->previous_ireduce_module);
}