xform.c

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/* -*- C -*- */
/*
 * Copyright (c) 2013-2020 Seagate Technology LLC and/or its Affiliates
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * For any questions about this software or licensing,
 * please email opensource@seagate.com or cortx-questions@seagate.com.
 *
 */


#define M0_TRACE_SUBSYSTEM M0_TRACE_SUBSYS_SNSCM
#include "lib/trace.h"

#include "fid/fid.h"
#include "reqh/reqh.h"

#include "cm/cm.h"

#include "sns/cm/ag.h"
#include "sns/cm/cp.h"

#include "sns/cm/cm_utils.h"

M0_INTERNAL int m0_sns_cm_rebalance_tgt_info(struct m0_sns_cm_ag *sag,
                                             struct m0_sns_cm_cp *scp);

M0_INTERNAL int m0_sns_cm_rebalance_cp_xform(struct m0_cm_cp *cp)
{
        struct m0_sns_cm_ag     *sns_ag;
        struct m0_sns_cm_cp     *scp;
        struct m0_cm_aggr_group *ag;
        struct m0_cm_ag_id       id;
        struct m0_cm            *cm;
        struct m0_cm_cp         *tgt_cp;
        enum m0_cm_cp_phase      phase;
        int                      rc;

        M0_PRE(cp != NULL && m0_fom_phase(&cp->c_fom) == M0_CCP_XFORM);

        ag = cp->c_ag;
        id = ag->cag_id;
        sns_ag = ag2snsag(ag);
        scp = cp2snscp(cp);
        cm = ag->cag_cm;
        m0_cm_ag_lock(ag);

        M0_LOG(M0_DEBUG, "xform: id ["M0_AG_F"] local_cp_nr: [%" PRIu64 "]"
                         "transformed_cp_nr: [%" PRIu64 "] has_incoming: %d\n",
                         M0_AG_P(&id), ag->cag_cp_local_nr,
                         ag->cag_transformed_cp_nr, !!ag->cag_has_incoming);

        /* Increment number of transformed copy packets in the accumulator. */
        M0_CNT_INC(ag->cag_transformed_cp_nr);
        if (!ag->cag_has_incoming)
                M0_ASSERT(ag->cag_transformed_cp_nr <= ag->cag_cp_local_nr);

        M0_ASSERT(m0_fid_is_set(&scp->sc_cobfid));
        rc = m0_sns_cm_rebalance_tgt_info(sns_ag, scp);
        M0_ASSERT(m0_fid_is_set(&scp->sc_cobfid));
        if (rc == 0) {
                /*
                 * Handle concurrancy of multiple copy packet foms writing
                 * to the same stob through different reqh localities by
                 * starting a duplicate copy packet fom for writing and
                 * finalising the source copy packet @cp.
                 * Concurrancy is handled by running the copy packet foms
                 * doing i/o to a same stob in the same reqh locality.
                 */
                rc = m0_sns_cm_cp_dup(cp, &tgt_cp);
                if (rc == 0) {
                        if (scp->sc_is_local) {
                                M0_CNT_INC(ag->cag_cp_local_nr);
                                M0_CNT_INC(sns_ag->sag_cp_created_nr);
                         } else
                                M0_CNT_INC(sns_ag->sag_incoming_cp_nr);

                        rc = m0_cm_cp_enqueue(cm, tgt_cp);
                }
        }

        if (rc == 0 || rc == -ENOENT) {
                phase = M0_CCP_FINI;
                rc = 0;
        } else
                phase = M0_CCP_FAIL;
        m0_fom_phase_move(&cp->c_fom, rc, phase);
        rc = phase == M0_CCP_FAIL ? M0_FSO_AGAIN : M0_FSO_WAIT;
        m0_cm_ag_unlock(ag);

        return M0_RC(rc);
}

#undef M0_TRACE_SUBSYSTEM

/*
 *  Local variables:
 *  c-indentation-style: "K&R"
 *  c-basic-offset: 8
 *  tab-width: 8
 *  fill-column: 80
 *  scroll-step: 1
 *  End:
 */