mirror of
https://github.com/ecency/ecency-mobile.git
synced 2024-12-20 20:01:56 +03:00
576 lines
18 KiB
C++
576 lines
18 KiB
C++
// Copyright (C) 2007 Trustees of Indiana University
|
|
|
|
// Authors: Douglas Gregor
|
|
// Andrew Lumsdaine
|
|
|
|
// Use, modification and distribution is subject to the Boost Software
|
|
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
|
|
// http://www.boost.org/LICENSE_1_0.txt)
|
|
|
|
/** @file graph_communicator.hpp
|
|
*
|
|
* This header defines facilities to support MPI communicators with
|
|
* graph topologies, using the graph interface defined by the Boost
|
|
* Graph Library. One can construct a communicator whose topology is
|
|
* described by any graph meeting the requirements of the Boost Graph
|
|
* Library's graph concepts. Likewise, any communicator that has a
|
|
* graph topology can be viewed as a graph by the Boost Graph
|
|
* Library, permitting one to use the BGL's graph algorithms on the
|
|
* process topology.
|
|
*/
|
|
#ifndef BOOST_MPI_GRAPH_COMMUNICATOR_HPP
|
|
#define BOOST_MPI_GRAPH_COMMUNICATOR_HPP
|
|
|
|
#include <boost/mpi/communicator.hpp>
|
|
#include <vector>
|
|
#include <utility>
|
|
|
|
// Headers required to implement graph topologies
|
|
#include <boost/graph/graph_traits.hpp>
|
|
#include <boost/graph/properties.hpp>
|
|
#include <boost/property_map/property_map.hpp>
|
|
#include <boost/iterator/counting_iterator.hpp>
|
|
#include <boost/graph/iteration_macros.hpp>
|
|
#include <boost/shared_array.hpp>
|
|
#include <boost/assert.hpp>
|
|
|
|
namespace boost { namespace mpi {
|
|
|
|
/**
|
|
* @brief An MPI communicator with a graph topology.
|
|
*
|
|
* A @c graph_communicator is a communicator whose topology is
|
|
* expressed as a graph. Graph communicators have the same
|
|
* functionality as (intra)communicators, but also allow one to query
|
|
* the relationships among processes. Those relationships are
|
|
* expressed via a graph, using the interface defined by the Boost
|
|
* Graph Library. The @c graph_communicator class meets the
|
|
* requirements of the BGL Graph, Incidence Graph, Adjacency Graph,
|
|
* Vertex List Graph, and Edge List Graph concepts.
|
|
*/
|
|
class BOOST_MPI_DECL graph_communicator : public communicator
|
|
{
|
|
friend class communicator;
|
|
|
|
/**
|
|
* INTERNAL ONLY
|
|
*
|
|
* Construct a graph communicator given a shared pointer to the
|
|
* underlying MPI_Comm. This operation is used for "casting" from a
|
|
* communicator to a graph communicator.
|
|
*/
|
|
explicit graph_communicator(const shared_ptr<MPI_Comm>& comm_ptr)
|
|
{
|
|
#ifndef BOOST_DISABLE_ASSERTS
|
|
int status;
|
|
BOOST_MPI_CHECK_RESULT(MPI_Topo_test, ((MPI_Comm)*this, &status));
|
|
BOOST_ASSERT(status == MPI_GRAPH);
|
|
#endif
|
|
this->comm_ptr = comm_ptr;
|
|
}
|
|
|
|
public:
|
|
/**
|
|
* Build a new Boost.MPI graph communicator based on the MPI
|
|
* communicator @p comm with graph topology.
|
|
*
|
|
* @p comm may be any valid MPI communicator. If @p comm is
|
|
* MPI_COMM_NULL, an empty communicator (that cannot be used for
|
|
* communication) is created and the @p kind parameter is
|
|
* ignored. Otherwise, the @p kind parameter determines how the
|
|
* Boost.MPI communicator will be related to @p comm:
|
|
*
|
|
* - If @p kind is @c comm_duplicate, duplicate @c comm to create
|
|
* a new communicator. This new communicator will be freed when
|
|
* the Boost.MPI communicator (and all copies of it) is
|
|
* destroyed. This option is only permitted if the underlying MPI
|
|
* implementation supports MPI 2.0; duplication of
|
|
* intercommunicators is not available in MPI 1.x.
|
|
*
|
|
* - If @p kind is @c comm_take_ownership, take ownership of @c
|
|
* comm. It will be freed automatically when all of the Boost.MPI
|
|
* communicators go out of scope.
|
|
*
|
|
* - If @p kind is @c comm_attach, this Boost.MPI communicator
|
|
* will reference the existing MPI communicator @p comm but will
|
|
* not free @p comm when the Boost.MPI communicator goes out of
|
|
* scope. This option should only be used when the communicator is
|
|
* managed by the user.
|
|
*/
|
|
graph_communicator(const MPI_Comm& comm, comm_create_kind kind)
|
|
: communicator(comm, kind)
|
|
{
|
|
#ifndef BOOST_DISABLE_ASSERTS
|
|
int status;
|
|
BOOST_MPI_CHECK_RESULT(MPI_Topo_test, ((MPI_Comm)*this, &status));
|
|
BOOST_ASSERT(status == MPI_GRAPH);
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* Create a new communicator whose topology is described by the
|
|
* given graph. The indices of the vertices in the graph will be
|
|
* assumed to be the ranks of the processes within the
|
|
* communicator. There may be fewer vertices in the graph than
|
|
* there are processes in the communicator; in this case, the
|
|
* resulting communicator will be a NULL communicator.
|
|
*
|
|
* @param comm The communicator that the new, graph communicator
|
|
* will be based on.
|
|
*
|
|
* @param graph Any type that meets the requirements of the
|
|
* Incidence Graph and Vertex List Graph concepts from the Boost Graph
|
|
* Library. This structure of this graph will become the topology
|
|
* of the communicator that is returned.
|
|
*
|
|
* @param reorder Whether MPI is permitted to re-order the process
|
|
* ranks within the returned communicator, to better optimize
|
|
* communication. If false, the ranks of each process in the
|
|
* returned process will match precisely the rank of that process
|
|
* within the original communicator.
|
|
*/
|
|
template<typename Graph>
|
|
explicit
|
|
graph_communicator(const communicator& comm, const Graph& graph,
|
|
bool reorder = false);
|
|
|
|
/**
|
|
* Create a new communicator whose topology is described by the
|
|
* given graph. The rank map (@p rank) gives the mapping from
|
|
* vertices in the graph to ranks within the communicator. There
|
|
* may be fewer vertices in the graph than there are processes in
|
|
* the communicator; in this case, the resulting communicator will
|
|
* be a NULL communicator.
|
|
*
|
|
* @param comm The communicator that the new, graph communicator
|
|
* will be based on. The ranks in @c rank refer to the processes in
|
|
* this communicator.
|
|
*
|
|
* @param graph Any type that meets the requirements of the
|
|
* Incidence Graph and Vertex List Graph concepts from the Boost Graph
|
|
* Library. This structure of this graph will become the topology
|
|
* of the communicator that is returned.
|
|
*
|
|
* @param rank This map translates vertices in the @c graph into
|
|
* ranks within the current communicator. It must be a Readable
|
|
* Property Map (see the Boost Property Map library) whose key type
|
|
* is the vertex type of the @p graph and whose value type is @c
|
|
* int.
|
|
*
|
|
* @param reorder Whether MPI is permitted to re-order the process
|
|
* ranks within the returned communicator, to better optimize
|
|
* communication. If false, the ranks of each process in the
|
|
* returned process will match precisely the rank of that process
|
|
* within the original communicator.
|
|
*/
|
|
template<typename Graph, typename RankMap>
|
|
explicit
|
|
graph_communicator(const communicator& comm, const Graph& graph,
|
|
RankMap rank, bool reorder = false);
|
|
|
|
protected:
|
|
/**
|
|
* INTERNAL ONLY
|
|
*
|
|
* Used by the constructors to create the new communicator with a
|
|
* graph topology.
|
|
*/
|
|
template<typename Graph, typename RankMap>
|
|
void
|
|
setup_graph(const communicator& comm, const Graph& graph, RankMap rank,
|
|
bool reorder);
|
|
};
|
|
|
|
/****************************************************************************
|
|
* Implementation Details *
|
|
****************************************************************************/
|
|
|
|
template<typename Graph>
|
|
graph_communicator::graph_communicator(const communicator& comm,
|
|
const Graph& graph,
|
|
bool reorder)
|
|
{
|
|
this->setup_graph(comm, graph, get(vertex_index, graph), reorder);
|
|
}
|
|
|
|
template<typename Graph, typename RankMap>
|
|
graph_communicator::graph_communicator(const communicator& comm,
|
|
const Graph& graph,
|
|
RankMap rank, bool reorder)
|
|
{
|
|
this->setup_graph(comm, graph, rank, reorder);
|
|
}
|
|
|
|
|
|
template<typename Graph, typename RankMap>
|
|
void
|
|
graph_communicator::setup_graph(const communicator& comm, const Graph& graph,
|
|
RankMap rank, bool reorder)
|
|
{
|
|
typedef typename graph_traits<Graph>::vertex_descriptor vertex_descriptor;
|
|
|
|
// Build a mapping from ranks to vertices
|
|
std::vector<vertex_descriptor> vertex_with_rank(num_vertices(graph));
|
|
if (vertex_with_rank.empty())
|
|
return;
|
|
|
|
BGL_FORALL_VERTICES_T(v, graph, Graph)
|
|
vertex_with_rank[get(rank, v)] = v;
|
|
|
|
// Build the representation of the graph required by
|
|
// MPI_Graph_create.
|
|
std::vector<int> indices(num_vertices(graph));
|
|
std::vector<int> edges;
|
|
int nvertices = indices.size();
|
|
for (int vertex_index = 0; vertex_index < nvertices; ++vertex_index) {
|
|
vertex_descriptor v = vertex_with_rank[vertex_index];
|
|
|
|
BGL_FORALL_OUTEDGES_T(v, e, graph, Graph)
|
|
edges.push_back(get(rank, target(e, graph)));
|
|
|
|
indices[vertex_index] = edges.size();
|
|
}
|
|
|
|
// Create the new communicator
|
|
MPI_Comm newcomm;
|
|
BOOST_MPI_CHECK_RESULT(MPI_Graph_create,
|
|
((MPI_Comm)comm,
|
|
nvertices,
|
|
&indices[0],
|
|
edges.empty()? (int*)0 : &edges[0],
|
|
reorder,
|
|
&newcomm));
|
|
this->comm_ptr.reset(new MPI_Comm(newcomm), comm_free());
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Communicator with Graph Topology as BGL Graph *
|
|
****************************************************************************/
|
|
namespace detail {
|
|
/**
|
|
* INTERNAL ONLY
|
|
*
|
|
* The iterator used to access the outgoing edges within a
|
|
* communicator's graph topology.
|
|
*/
|
|
class comm_out_edge_iterator
|
|
: public iterator_facade<comm_out_edge_iterator,
|
|
std::pair<int, int>,
|
|
random_access_traversal_tag,
|
|
const std::pair<int, int>&,
|
|
int>
|
|
{
|
|
public:
|
|
comm_out_edge_iterator() { }
|
|
|
|
comm_out_edge_iterator(int source, shared_array<int> neighbors, int index)
|
|
: edge(source, -1), neighbors(neighbors), index(index) { }
|
|
|
|
protected:
|
|
friend class boost::iterator_core_access;
|
|
|
|
const std::pair<int, int>& dereference() const
|
|
{
|
|
edge.second = neighbors[index];
|
|
return edge;
|
|
}
|
|
|
|
bool equal(const comm_out_edge_iterator& other) const
|
|
{
|
|
return (edge.first == other.edge.first
|
|
&& index == other.index);
|
|
}
|
|
|
|
void increment() { ++index; }
|
|
|
|
void decrement() { --index; }
|
|
|
|
void advance(int n) { index += n; }
|
|
|
|
int distance_to(const comm_out_edge_iterator& other) const
|
|
{
|
|
return other.index - index;
|
|
}
|
|
|
|
mutable std::pair<int, int> edge;
|
|
shared_array<int> neighbors;
|
|
int index;
|
|
};
|
|
|
|
/**
|
|
* INTERNAL ONLY
|
|
*
|
|
* The iterator used to access the adjacent vertices within a
|
|
* communicator's graph topology.
|
|
*/
|
|
class comm_adj_iterator
|
|
: public iterator_facade<comm_adj_iterator,
|
|
int,
|
|
random_access_traversal_tag,
|
|
int,
|
|
int>
|
|
{
|
|
public:
|
|
comm_adj_iterator() { }
|
|
|
|
comm_adj_iterator(shared_array<int> neighbors, int index)
|
|
: neighbors(neighbors), index(index) { }
|
|
|
|
protected:
|
|
friend class boost::iterator_core_access;
|
|
|
|
int dereference() const { return neighbors[index]; }
|
|
|
|
bool equal(const comm_adj_iterator& other) const
|
|
{
|
|
return (neighbors == other.neighbors
|
|
&& index == other.index);
|
|
}
|
|
|
|
void increment() { ++index; }
|
|
|
|
void decrement() { --index; }
|
|
|
|
void advance(int n) { index += n; }
|
|
|
|
int distance_to(const comm_adj_iterator& other) const
|
|
{
|
|
return other.index - index;
|
|
}
|
|
|
|
shared_array<int> neighbors;
|
|
int index;
|
|
};
|
|
|
|
/**
|
|
* INTERNAL ONLY
|
|
*
|
|
* The iterator used to access the edges in a communicator's graph
|
|
* topology.
|
|
*/
|
|
class comm_edge_iterator
|
|
: public iterator_facade<comm_edge_iterator,
|
|
std::pair<int, int>,
|
|
forward_traversal_tag,
|
|
const std::pair<int, int>&,
|
|
int>
|
|
{
|
|
public:
|
|
comm_edge_iterator() { }
|
|
|
|
/// Constructor for a past-the-end iterator
|
|
comm_edge_iterator(int nedges) : edge_index(nedges) { }
|
|
|
|
comm_edge_iterator(shared_array<int> indices, shared_array<int> edges)
|
|
: indices(indices), edges(edges), edge_index(0), edge(0, 0)
|
|
{ }
|
|
|
|
protected:
|
|
friend class boost::iterator_core_access;
|
|
|
|
const std::pair<int, int>& dereference() const
|
|
{
|
|
while (edge_index == indices[edge.first])
|
|
++edge.first;
|
|
edge.second = edges[edge_index];
|
|
return edge;
|
|
}
|
|
|
|
bool equal(const comm_edge_iterator& other) const
|
|
{
|
|
return edge_index == other.edge_index;
|
|
}
|
|
|
|
void increment()
|
|
{
|
|
++edge_index;
|
|
}
|
|
|
|
shared_array<int> indices;
|
|
shared_array<int> edges;
|
|
int edge_index;
|
|
mutable std::pair<int, int> edge;
|
|
};
|
|
|
|
} // end namespace detail
|
|
|
|
// Incidence Graph requirements
|
|
|
|
/**
|
|
* @brief Returns the source vertex from an edge in the graph topology
|
|
* of a communicator.
|
|
*/
|
|
inline int source(const std::pair<int, int>& edge, const graph_communicator&)
|
|
{
|
|
return edge.first;
|
|
}
|
|
|
|
/**
|
|
* @brief Returns the target vertex from an edge in the graph topology
|
|
* of a communicator.
|
|
*/
|
|
inline int target(const std::pair<int, int>& edge, const graph_communicator&)
|
|
{
|
|
return edge.second;
|
|
}
|
|
|
|
/**
|
|
* @brief Returns an iterator range containing all of the edges
|
|
* outgoing from the given vertex in a graph topology of a
|
|
* communicator.
|
|
*/
|
|
std::pair<detail::comm_out_edge_iterator, detail::comm_out_edge_iterator>
|
|
out_edges(int vertex, const graph_communicator& comm);
|
|
|
|
|
|
/**
|
|
* @brief Returns the out-degree of a vertex in the graph topology of
|
|
* a communicator.
|
|
*/
|
|
int out_degree(int vertex, const graph_communicator& comm);
|
|
|
|
// Adjacency Graph requirements
|
|
|
|
/**
|
|
* @brief Returns an iterator range containing all of the neighbors of
|
|
* the given vertex in the communicator's graph topology.
|
|
*/
|
|
std::pair<detail::comm_adj_iterator, detail::comm_adj_iterator>
|
|
adjacent_vertices(int vertex, const graph_communicator& comm);
|
|
|
|
// Vertex List Graph requirements
|
|
|
|
/**
|
|
* @brief Returns an iterator range that contains all of the vertices
|
|
* with the communicator's graph topology, i.e., all of the process
|
|
* ranks in the communicator.
|
|
*/
|
|
inline std::pair<counting_iterator<int>, counting_iterator<int> >
|
|
vertices(const graph_communicator& comm)
|
|
{
|
|
return std::make_pair(counting_iterator<int>(0),
|
|
counting_iterator<int>(comm.size()));
|
|
}
|
|
|
|
/**
|
|
* @brief Returns the number of vertices within the graph topology of
|
|
* the communicator, i.e., the number of processes in the
|
|
* communicator.
|
|
*/
|
|
inline int num_vertices(const graph_communicator& comm) { return comm.size(); }
|
|
|
|
// Edge List Graph requirements
|
|
|
|
/**
|
|
* @brief Returns an iterator range that contains all of the edges
|
|
* with the communicator's graph topology.
|
|
*/
|
|
std::pair<detail::comm_edge_iterator, detail::comm_edge_iterator>
|
|
edges(const graph_communicator& comm);
|
|
|
|
/**
|
|
* @brief Returns the number of edges in the communicator's graph
|
|
* topology.
|
|
*/
|
|
int num_edges(const graph_communicator& comm);
|
|
|
|
// Property Graph requirements
|
|
|
|
/**
|
|
* @brief Returns a property map that maps from vertices in a
|
|
* communicator's graph topology to their index values.
|
|
*
|
|
* Since the vertices are ranks in the communicator, the returned
|
|
* property map is the identity property map.
|
|
*/
|
|
inline identity_property_map get(vertex_index_t, const graph_communicator&)
|
|
{
|
|
return identity_property_map();
|
|
}
|
|
|
|
/**
|
|
* @brief Returns the index of a vertex in the communicator's graph
|
|
* topology.
|
|
*
|
|
* Since the vertices are ranks in the communicator, this is the
|
|
* identity function.
|
|
*/
|
|
inline int get(vertex_index_t, const graph_communicator&, int vertex)
|
|
{
|
|
return vertex;
|
|
}
|
|
|
|
} } // end namespace boost::mpi
|
|
|
|
namespace boost {
|
|
|
|
/**
|
|
* @brief Traits structure that allows a communicator with graph
|
|
* topology to be view as a graph by the Boost Graph Library.
|
|
*
|
|
* The specialization of @c graph_traits for an MPI communicator
|
|
* allows a communicator with graph topology to be viewed as a
|
|
* graph. An MPI communicator with graph topology meets the
|
|
* requirements of the Graph, Incidence Graph, Adjacency Graph, Vertex
|
|
* List Graph, and Edge List Graph concepts from the Boost Graph
|
|
* Library.
|
|
*/
|
|
template<>
|
|
struct graph_traits<mpi::graph_communicator> {
|
|
// Graph concept requirements
|
|
typedef int vertex_descriptor;
|
|
typedef std::pair<int, int> edge_descriptor;
|
|
typedef directed_tag directed_category;
|
|
typedef disallow_parallel_edge_tag edge_parallel_category;
|
|
|
|
/**
|
|
* INTERNAL ONLY
|
|
*/
|
|
struct traversal_category
|
|
: incidence_graph_tag,
|
|
adjacency_graph_tag,
|
|
vertex_list_graph_tag,
|
|
edge_list_graph_tag
|
|
{
|
|
};
|
|
|
|
/**
|
|
* @brief Returns a vertex descriptor that can never refer to any
|
|
* valid vertex.
|
|
*/
|
|
static vertex_descriptor null_vertex() { return -1; }
|
|
|
|
// Incidence Graph requirements
|
|
typedef mpi::detail::comm_out_edge_iterator out_edge_iterator;
|
|
typedef int degree_size_type;
|
|
|
|
// Adjacency Graph requirements
|
|
typedef mpi::detail::comm_adj_iterator adjacency_iterator;
|
|
|
|
// Vertex List Graph requirements
|
|
typedef counting_iterator<int> vertex_iterator;
|
|
typedef int vertices_size_type;
|
|
|
|
// Edge List Graph requirements
|
|
typedef mpi::detail::comm_edge_iterator edge_iterator;
|
|
typedef int edges_size_type;
|
|
};
|
|
|
|
// Property Graph requirements
|
|
|
|
/**
|
|
* INTERNAL ONLY
|
|
*/
|
|
template<>
|
|
struct property_map<mpi::graph_communicator, vertex_index_t>
|
|
{
|
|
typedef identity_property_map type;
|
|
typedef identity_property_map const_type;
|
|
};
|
|
|
|
} // end namespace boost
|
|
|
|
|
|
|
|
#endif // BOOST_MPI_GRAPH_COMMUNICATOR_HPP
|