openmpi/ompi/communicator/communicator.h

/* -*- Mode: C; c-basic-offset:4 ; -*- */
/*
 * Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
 *                         University Research and Technology
 *                         Corporation.  All rights reserved.
 * Copyright (c) 2004-2007 The University of Tennessee and The University
 *                         of Tennessee Research Foundation.  All rights
 *                         reserved.
 * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart, 
 *                         University of Stuttgart.  All rights reserved.
 * Copyright (c) 2004-2005 The Regents of the University of California.
 *                         All rights reserved.
 * Copyright (c) 2006      Cisco Systems, Inc.  All rights reserved.
 * Copyright (c) 2006-2007 University of Houston. All rights reserved.
 * $COPYRIGHT$
 * 
 * Additional copyrights may follow
 * 
 * $HEADER$
 */

#ifndef OMPI_COMMUNICATOR_H
#define OMPI_COMMUNICATOR_H

#include "opal/class/opal_object.h"
#include "ompi/errhandler/errhandler.h"
#include "opal/threads/mutex.h"

#include "mpi.h"
#include "ompi/group/group.h"
#include "ompi/mca/coll/coll.h"
#include "orte/mca/rml/rml_types.h"
#include "ompi/proc/proc.h"

BEGIN_C_DECLS

OMPI_DECLSPEC OBJ_CLASS_DECLARATION(ompi_communicator_t);

#define OMPI_COMM_INTER      0x00000001
#define OMPI_COMM_CART       0x00000002
#define OMPI_COMM_GRAPH      0x00000004
#define OMPI_COMM_NAMEISSET  0x00000008
#define OMPI_COMM_ISFREED    0x00000010
#define OMPI_COMM_INTRINSIC  0x00000020
#define OMPI_COMM_DYNAMIC    0x00000040
#define OMPI_COMM_INVALID    0x00000080
#define OMPI_COMM_PML_ADDED  0x00000100

/* some utility #defines */
#define OMPI_COMM_IS_INTER(comm) ((comm)->c_flags & OMPI_COMM_INTER)
#define OMPI_COMM_IS_INTRA(comm) (!((comm)->c_flags & OMPI_COMM_INTER))
#define OMPI_COMM_IS_CART(comm) ((comm)->c_flags & OMPI_COMM_CART)
#define OMPI_COMM_IS_GRAPH(comm) ((comm)->c_flags & OMPI_COMM_GRAPH)
#define OMPI_COMM_IS_INTRINSIC(comm) ((comm)->c_flags & OMPI_COMM_INTRINSIC)
#define OMPI_COMM_IS_FREED(comm) ((comm)->c_flags & OMPI_COMM_ISFREED)
#define OMPI_COMM_IS_DYNAMIC(comm) ((comm)->c_flags & OMPI_COMM_DYNAMIC)
#define OMPI_COMM_IS_INVALID(comm) ((comm)->c_flags & OMPI_COMM_INVALID)
#define OMPI_COMM_IS_PML_ADDED(comm) ((comm)->c_flags & OMPI_COMM_PML_ADDED)

#define OMPI_COMM_SET_DYNAMIC(comm) ((comm)->c_flags |= OMPI_COMM_DYNAMIC)
#define OMPI_COMM_SET_INVALID(comm) ((comm)->c_flags |= OMPI_COMM_INVALID)

#define OMPI_COMM_SET_PML_ADDED(comm) ((comm)->c_flags |= OMPI_COMM_PML_ADDED)

/* a set of special tags: */

/*  to recognize an MPI_Comm_join in the comm_connect_accept routine. */

#define OMPI_COMM_ALLGATHER_TAG -31078
#define OMPI_COMM_BARRIER_TAG   -31079
#define OMPI_COMM_ALLREDUCE_TAG -31080

/**
 * Modes required for acquiring the new comm-id.
 * The first (INTER/INTRA) indicates whether the
 * input comm was an inter/intra-comm, the second
 * whether the new communicator will be an inter/intra
 * comm
 */
#define OMPI_COMM_CID_INTRA        0x00000020
#define OMPI_COMM_CID_INTER        0x00000040
#define OMPI_COMM_CID_INTRA_BRIDGE 0x00000080
#define OMPI_COMM_CID_INTRA_OOB    0x00000100

/**
 * The block of CIDs allocated for MPI_COMM_WORLD
 * and other communicators
 */
#define OMPI_COMM_BLOCK_WORLD      16
#define OMPI_COMM_BLOCK_OTHERS     8

OMPI_DECLSPEC extern opal_pointer_array_t ompi_mpi_communicators;

struct ompi_communicator_t {
    opal_object_t              c_base;
    opal_mutex_t               c_lock; /* mutex for name and potentially
                                          attributes */
    char  c_name[MPI_MAX_OBJECT_NAME];
    uint32_t              c_contextid;
    int                     c_my_rank;
    uint32_t                  c_flags; /* flags, e.g. intercomm,
                                          topology, etc. */

    int c_id_available; /* the currently available Cid for allocation 
               to a child*/
    int c_id_start_index; /* the starting index of the block of cids 
                 allocated to tthis communicator*/

    ompi_group_t        *c_local_group;
    ompi_group_t       *c_remote_group;

    struct ompi_communicator_t *c_local_comm; /* a duplicate of the local 
                                                 communicator in case the comm  
                                                 is an inter-comm*/
                     
    /* Attributes */
    struct opal_hash_table_t       *c_keyhash;

    /**< inscribing cube dimension */
    int c_cube_dim;

    /* Hooks for topo module to hang things */
    mca_base_component_t *c_topo_component;

    const struct mca_topo_base_module_1_0_0_t* c_topo; 
    /**< structure of function pointers */

    struct mca_topo_base_comm_1_0_0_t* c_topo_comm; 
    /**< structure containing basic information about the topology */

    struct mca_topo_base_module_comm_t *c_topo_module;
    /**< module specific data */

    /* index in Fortran <-> C translation array */

    int c_f_to_c_index;

#ifdef OMPI_WANT_PERUSE
    /*
     * Place holder for the PERUSE events.
     */
    struct ompi_peruse_handle_t** c_peruse_handles;
#endif

    /* Error handling.  This field does not have the "c_" prefix so
       that the OMPI_ERRHDL_* macros can find it, regardless of whether
       it's a comm, window, or file. */

    ompi_errhandler_t                  *error_handler;
    ompi_errhandler_type_t             errhandler_type;

    /* Hooks for PML to hang things */
    struct mca_pml_comm_t  *c_pml_comm;

    /* Collectives module interface and data */
    mca_coll_base_comm_coll_t c_coll;
};
    typedef struct ompi_communicator_t ompi_communicator_t;
    OMPI_DECLSPEC extern ompi_communicator_t *ompi_mpi_comm_parent;
    OMPI_DECLSPEC extern ompi_communicator_t ompi_mpi_comm_null;


    /**
     * Is this a valid communicator?  This is a complicated question.
     * :-)
     *
     * According to MPI-1:5.2.4 (p137):
     *
     * "The predefined constant MPI_COMM_NULL is the value used for
     * invalid communicator handles."
     *
     * Hence, MPI_COMM_NULL is not valid.  However, MPI-2:4.12.4 (p50)
     * clearly states that the MPI_*_C2F and MPI_*_F2C functions
     * should treat MPI_COMM_NULL as a valid communicator -- it
     * distinctly differentiates between "invalid" handles and
     * "MPI_*_NULL" handles.  Some feel that the MPI-1 definition
     * still holds for all other MPI functions; others feel that the
     * MPi-2 definitions trump the MPI-1 definition.  Regardless of
     * who is right, there is ambiguity here.  So we have left
     * ompi_comm_invalid() as originally coded -- per the MPI-1
     * definition, where MPI_COMM_NULL is an invalid communicator.
     * The MPI_Comm_c2f() function, therefore, calls
     * ompi_comm_invalid() but also explictily checks to see if the
     * handle is MPI_COMM_NULL.
     */
    static inline int ompi_comm_invalid(ompi_communicator_t* comm)
    {
        if ((NULL == comm) || (MPI_COMM_NULL == comm) ||
            (OMPI_COMM_IS_FREED(comm)) || (OMPI_COMM_IS_INVALID(comm)) )
            return true;
        else
            return false;
    }

    /**
     * rank w/in the communicator
     */
    static inline int ompi_comm_rank(ompi_communicator_t* comm)
    {
        return comm->c_my_rank;
    }

    /**
     * size of the communicator
     */
    static inline int ompi_comm_size(ompi_communicator_t* comm)
    {
        return comm->c_local_group->grp_proc_count;
    }

    /**
     * size of the remote group for inter-communicators.
     * returns zero for an intra-communicator
     */
    static inline int ompi_comm_remote_size(ompi_communicator_t* comm)
    {
        return (comm->c_flags & OMPI_COMM_INTER ? comm->c_remote_group->grp_proc_count : 0);
    }

    /** 
     * Context ID for the communicator, suitable for passing to
     * ompi_comm_lookup for getting the communicator back 
     */
    static inline uint32_t ompi_comm_get_cid(ompi_communicator_t* comm) 
    {
        return comm->c_contextid;
    }

    /* return pointer to communicator associated with context id cid,
     * No error checking is done*/
    static inline ompi_communicator_t *ompi_comm_lookup(uint32_t cid)
    {
        /* array of pointers to communicators, indexed by context ID */
        return (ompi_communicator_t*)opal_pointer_array_get_item(&ompi_mpi_communicators, cid);
    }

    static inline struct ompi_proc_t* ompi_comm_peer_lookup(ompi_communicator_t* comm, int peer_id)
    {
#if OMPI_ENABLE_DEBUG
        if(peer_id >= comm->c_remote_group->grp_proc_count) {
            opal_output(0, "ompi_comm_lookup_peer: invalid peer index (%d)", peer_id);
            return (struct ompi_proc_t *) NULL;
        }
#endif
        /*return comm->c_remote_group->grp_proc_pointers[peer_id];*/
        return ompi_group_peer_lookup(comm->c_remote_group,peer_id);
    }

    static inline bool ompi_comm_peer_invalid(ompi_communicator_t* comm, int peer_id)
    {
        if(peer_id < 0 || peer_id >= comm->c_remote_group->grp_proc_count) {
            return true;
        }
        return false;
    }


    /**
     * Initialise MPI_COMM_WORLD and MPI_COMM_SELF
     */
    int ompi_comm_init(void);
    OMPI_DECLSPEC int ompi_comm_link_function(void);

    /**
     * extract the local group from a communicator
     */
    OMPI_DECLSPEC int ompi_comm_group (ompi_communicator_t *comm, ompi_group_t **group);

    /**
     * create a communicator based on a group
     */
    int ompi_comm_create (ompi_communicator_t* comm, ompi_group_t *group,
                          ompi_communicator_t** newcomm);


    /**
     * create a cartesian communicator
     */
    int ompi_topo_create (ompi_communicator_t *old_comm,
                          int ndims_or_nnodes,
                          int *dims_or_index,
                          int *periods_or_edges,
                          bool reorder,
                          ompi_communicator_t **comm_cart,
                          int cart_or_graph);

    /**
     * split a communicator based on color and key. Parameters
     * are identical to the MPI-counterpart of the function.
     *
     * @param comm: input communicator
     * @param color
     * @param key
     *
     * @
     */
    OMPI_DECLSPEC int ompi_comm_split (ompi_communicator_t *comm, int color, int key,
                         ompi_communicator_t** newcomm, bool pass_on_topo);

    /**
     * dup a communicator. Parameter are identical to the MPI-counterpart
     * of the function. It has been extracted, since we need to be able
     * to dup a communicator internally as well.
     *
     * @param comm:      input communicator
     *        sync_flag: 0 if processes need to synchronize in activate
     *                   1 if the do not (optimization to c_local_comm creation)
     *
     */
    OMPI_DECLSPEC int ompi_comm_dup (ompi_communicator_t *comm, ompi_communicator_t **newcomm, 
                       int sync_flag);

     /**
     * compare two communicators.
     *
     * @param comm1,comm2: input communicators
     *
     */
    int ompi_comm_compare(ompi_communicator_t *comm1, ompi_communicator_t *comm2, int *result);

    /**
     * free a communicator
     */
    OMPI_DECLSPEC int ompi_comm_free (ompi_communicator_t **comm);

    /**
     * allocate a new communicator structure
     * @param local_group_size
     * @param remote_group_size
     *
     * This routine allocates the structure, the according local and
     * remote groups, the proc-arrays in the local and remote group.
     * It furthermore sets the fortran index correctly,
     * and sets all other elements to zero.
     */
    ompi_communicator_t* ompi_comm_allocate (int local_group_size,
                                             int remote_group_size);

    /**
     * allocate new communicator ID
     * @param newcomm:    pointer to the new communicator
     * @param oldcomm:    original comm
     * @param bridgecomm: bridge comm for intercomm_create
     * @param mode: combination of input
     *              OMPI_COMM_CID_INTRA:        intra-comm
     *              OMPI_COMM_CID_INTER:        inter-comm
     *              OMPI_COMM_CID_INTRA_BRIDGE: 2 intracomms connected by
     *                                          a bridge comm. local_leader
     *                                          and remote leader are in this
     *                                          case an int (rank in bridge-comm).
     *              OMPI_COMM_CID_INTRA_OOB:    2 intracomms, leaders talk
     *                                          through OOB. lleader and rleader
     *                                          are the required contact information.
     * @param send_first: to avoid a potential deadlock for
     *                    the OOB version.
     * This routine has to be thread safe in the final version.
     */
OMPI_DECLSPEC int ompi_comm_nextcid ( ompi_communicator_t* newcomm,
                            ompi_communicator_t* oldcomm,
                            ompi_communicator_t* bridgecomm,
                            void* local_leader,
                            void* remote_leader,
                            int mode,
                            int send_first);

    /**
     * shut down the communicator infrastructure.
     */
    int ompi_comm_finalize (void);

    /**
     * This is THE routine, where all the communicator stuff
     * is really set.
     */
OMPI_DECLSPEC int ompi_comm_set ( ompi_communicator_t** newcomm,
                        ompi_communicator_t* oldcomm,
                        int local_size,
                        int *local_ranks,
                        int remote_size,
                        int *remote_ranks,
                        opal_hash_table_t *attr,
                        ompi_errhandler_t *errh,
                        mca_base_component_t *topocomponent,
                        ompi_group_t *local_group,
                        ompi_group_t *remote_group   );
    /**
     * This is a short-hand routine used in intercomm_create.
     * The routine makes sure, that all processes have afterwards
     * a list of ompi_proc_t pointers for the remote group.
     */
    struct ompi_proc_t **ompi_comm_get_rprocs ( ompi_communicator_t *local_comm,
                                       ompi_communicator_t *bridge_comm,
                                       int local_leader,
                                       int remote_leader,
                                       orte_rml_tag_t tag,
                                       int rsize);

    /**
     * This routine verifies, whether local_group and remote group are overlapping
     * in intercomm_create
     */
    int ompi_comm_overlapping_groups (int size, struct ompi_proc_t ** lprocs,
                                      int rsize, struct ompi_proc_t ** rprocs);

    /**
     * This is a routine determining whether the local or the
     * remote group will be first in the new intra-comm.
     * Just used from within MPI_Intercomm_merge.
     */
    int ompi_comm_determine_first ( ompi_communicator_t *intercomm,
                                   int high );


OMPI_DECLSPEC int ompi_comm_activate ( ompi_communicator_t* newcomm,
                             ompi_communicator_t* oldcomm,
                             ompi_communicator_t* bridgecomm,
                             void* local_leader,
                             void* remote_leader,
                             int mode,
                             int send_first,
                             int sync_flag );


    /**
     * a simple function to dump the structure
     */
    int ompi_comm_dump ( ompi_communicator_t *comm );

    /* setting name */
    int ompi_comm_set_name (ompi_communicator_t *comm, char *name );

    /*
     * these are the init and finalize functions for the comm_reg
     * stuff. These routines are necessary for handling multi-threading
     * scenarious in the communicator_cid allocation
     */
    void ompi_comm_reg_init(void);
    void ompi_comm_reg_finalize(void);

    /* global variable to save the number od dynamic communicators */
    extern int ompi_comm_num_dyncomm;


END_C_DECLS

#endif /* OMPI_COMMUNICATOR_H */