xref: /petsc/include/petscsf.h (revision bdf89e91df64bd49f4414ba801fb07e6338da027)
1 /*
2    A star forest (SF) describes a communication pattern
3 */
4 #if !defined(__PETSCSF_H)
5 #define __PETSCSF_H
6 #include <petscsys.h>
7 
8 PETSC_EXTERN PetscClassId PETSCSF_CLASSID;
9 
10 /*S
11    PetscSF - PETSc object for setting up and managing the communication of certain entries of arrays and Vecs between MPI processes.
12 
13    Level: intermediate
14 
15   Concepts: star forest
16 
17        PetscSF uses the concept of star forests to indicate and determine the communication patterns concisely and efficiently.
18   A star  http://en.wikipedia.org/wiki/Star_(graph_theory) forest is simply a collection of trees of height 1. The leave nodes represent
19   "ghost locations" for the root nodes.
20 
21 .seealso: PetscSFCreate(), VecScatter, VecScatterCreate()
22 S*/
23 typedef struct _p_PetscSF* PetscSF;
24 
25 
26 /*J
27     PetscSFType - String with the name of a PetscSF method or the creation function
28        with an optional dynamic library name, for example
29        http://www.mcs.anl.gov/petsc/lib.so:mysfcreate()
30 
31    Level: beginner
32 
33    Notes: The two approaches provided are
34 $     PETSCSFBASIC which uses MPI 1 message passing to perform the communication and
35 $     PETSCSFWINDOW which uses MPI 2 one-sided operations to perform the communication, this may be more efficient,
36 $                   but may not be available for all MPI distributions. In particular OpenMPI has bugs in its one-sided
37 $                   operations that prevent its use.
38 
39 .seealso: PetscSFSetType(), PetscSF
40 J*/
41 typedef const char *PetscSFType;
42 #define PETSCSFBASIC  "basic"
43 #define PETSCSFWINDOW "window"
44 
45 /*S
46    PetscSFNode - specifier of owner and index
47 
48    Level: beginner
49 
50   Concepts: indexing, stride, distribution
51 
52 .seealso: PetscSFSetGraph()
53 S*/
54 typedef struct {
55   PetscInt rank;                /* Rank of owner */
56   PetscInt index;               /* Index of node on rank */
57 } PetscSFNode;
58 
59 /*E
60     PetscSFWindowSyncType - Type of synchronization for PETSCSFWINDOW
61 
62 $  PETSCSF_WINDOW_SYNC_FENCE - simplest model, synchronizing across communicator
63 $  PETSCSF_WINDOW_SYNC_LOCK - passive model, less synchronous, requires less setup than PETSCSF_WINDOW_SYNC_ACTIVE, but may require more handshakes
64 $  PETSCSF_WINDOW_SYNC_ACTIVE - active model, provides most information to MPI implementation, needs to construct 2-way process groups (more setup than PETSCSF_WINDOW_SYNC_LOCK)
65 
66    Level: advanced
67 
68 .seealso: PetscSFWindowSetSyncType(), PetscSFWindowGetSyncType()
69 E*/
70 typedef enum {PETSCSF_WINDOW_SYNC_FENCE,PETSCSF_WINDOW_SYNC_LOCK,PETSCSF_WINDOW_SYNC_ACTIVE} PetscSFWindowSyncType;
71 PETSC_EXTERN const char *const PetscSFWindowSyncTypes[];
72 
73 /*E
74     PetscSFDuplicateOption - Aspects to preserve when duplicating a PetscSF
75 
76 $  PETSCSF_DUPLICATE_CONFONLY - configuration only, user must call PetscSFSetGraph()
77 $  PETSCSF_DUPLICATE_RANKS - communication ranks preserved, but different graph (allows simpler setup after calling PetscSFSetGraph())
78 $  PETSCSF_DUPLICATE_GRAPH - entire graph duplicated
79 
80    Level: beginner
81 
82 .seealso: PetscSFDuplicate()
83 E*/
84 typedef enum {PETSCSF_DUPLICATE_CONFONLY,PETSCSF_DUPLICATE_RANKS,PETSCSF_DUPLICATE_GRAPH} PetscSFDuplicateOption;
85 PETSC_EXTERN const char *const PetscSFDuplicateOptions[];
86 
87 PETSC_EXTERN PetscFunctionList PetscSFunctionList;
88 PETSC_EXTERN PetscErrorCode PetscSFRegisterDestroy(void);
89 PETSC_EXTERN PetscErrorCode PetscSFRegisterAll(void);
90 PETSC_EXTERN PetscErrorCode PetscSFRegister(const char[],PetscErrorCode (*)(PetscSF));
91 
92 PETSC_EXTERN PetscErrorCode PetscSFInitializePackage(void);
93 PETSC_EXTERN PetscErrorCode PetscSFFinalizePackage(void);
94 PETSC_EXTERN PetscErrorCode PetscSFCreate(MPI_Comm comm,PetscSF*);
95 PETSC_EXTERN PetscErrorCode PetscSFDestroy(PetscSF*);
96 PETSC_EXTERN PetscErrorCode PetscSFSetType(PetscSF,PetscSFType);
97 PETSC_EXTERN PetscErrorCode PetscSFView(PetscSF,PetscViewer);
98 PETSC_EXTERN PetscErrorCode PetscSFSetUp(PetscSF);
99 PETSC_EXTERN PetscErrorCode PetscSFSetFromOptions(PetscSF);
100 PETSC_EXTERN PetscErrorCode PetscSFDuplicate(PetscSF,PetscSFDuplicateOption,PetscSF*);
101 PETSC_EXTERN PetscErrorCode PetscSFWindowSetSyncType(PetscSF,PetscSFWindowSyncType);
102 PETSC_EXTERN PetscErrorCode PetscSFWindowGetSyncType(PetscSF,PetscSFWindowSyncType*);
103 PETSC_EXTERN PetscErrorCode PetscSFSetRankOrder(PetscSF,PetscBool);
104 PETSC_EXTERN PetscErrorCode PetscSFSetGraph(PetscSF,PetscInt,PetscInt,const PetscInt*,PetscCopyMode,const PetscSFNode*,PetscCopyMode);
105 PETSC_EXTERN PetscErrorCode PetscSFGetGraph(PetscSF,PetscInt *nroots,PetscInt *nleaves,const PetscInt **ilocal,const PetscSFNode **iremote);
106 PETSC_EXTERN PetscErrorCode PetscSFGetLeafRange(PetscSF,PetscInt*,PetscInt*);
107 PETSC_EXTERN PetscErrorCode PetscSFCreateEmbeddedSF(PetscSF,PetscInt nroots,const PetscInt *selected,PetscSF *newsf);
108 PETSC_EXTERN PetscErrorCode PetscSFReset(PetscSF);
109 PETSC_EXTERN PetscErrorCode PetscSFGetRanks(PetscSF,PetscInt*,const PetscMPIInt**,const PetscInt**,const PetscInt**,const PetscInt**);
110 PETSC_EXTERN PetscErrorCode PetscSFGetGroups(PetscSF,MPI_Group*,MPI_Group*);
111 PETSC_EXTERN PetscErrorCode PetscSFGetMultiSF(PetscSF,PetscSF*);
112 PETSC_EXTERN PetscErrorCode PetscSFCreateInverseSF(PetscSF,PetscSF*);
113 
114 /* broadcasts rootdata to leafdata */
115 PETSC_EXTERN PetscErrorCode PetscSFBcastBegin(PetscSF,MPI_Datatype,const void *rootdata,void *leafdata)
116   PetscAttrMPIPointerWithType(3,2) PetscAttrMPIPointerWithType(4,2);
117 PETSC_EXTERN PetscErrorCode PetscSFBcastEnd(PetscSF,MPI_Datatype,const void *rootdata,void *leafdata)
118   PetscAttrMPIPointerWithType(3,2) PetscAttrMPIPointerWithType(4,2);
119 /* Reduce leafdata into rootdata using provided operation */
120 PETSC_EXTERN PetscErrorCode PetscSFReduceBegin(PetscSF,MPI_Datatype,const void *leafdata,void *rootdata,MPI_Op)
121   PetscAttrMPIPointerWithType(3,2) PetscAttrMPIPointerWithType(4,2);
122 PETSC_EXTERN PetscErrorCode PetscSFReduceEnd(PetscSF,MPI_Datatype,const void *leafdata,void *rootdata,MPI_Op)
123   PetscAttrMPIPointerWithType(3,2) PetscAttrMPIPointerWithType(4,2);
124 /* Atomically modifies (using provided operation) rootdata using leafdata from each leaf, value at root at time of modification is returned in leafupdate. */
125 PETSC_EXTERN PetscErrorCode PetscSFFetchAndOpBegin(PetscSF,MPI_Datatype,void *rootdata,const void *leafdata,void *leafupdate,MPI_Op)
126   PetscAttrMPIPointerWithType(3,2) PetscAttrMPIPointerWithType(4,2) PetscAttrMPIPointerWithType(5,2);
127 PETSC_EXTERN PetscErrorCode PetscSFFetchAndOpEnd(PetscSF,MPI_Datatype,void *rootdata,const void *leafdata,void *leafupdate,MPI_Op)
128   PetscAttrMPIPointerWithType(3,2) PetscAttrMPIPointerWithType(4,2) PetscAttrMPIPointerWithType(5,2);
129 /* Compute the degree of every root vertex (number of leaves in its star) */
130 PETSC_EXTERN PetscErrorCode PetscSFComputeDegreeBegin(PetscSF,const PetscInt **degree);
131 PETSC_EXTERN PetscErrorCode PetscSFComputeDegreeEnd(PetscSF,const PetscInt **degree);
132 /* Concatenate data from all leaves into roots */
133 PETSC_EXTERN PetscErrorCode PetscSFGatherBegin(PetscSF,MPI_Datatype,const void *leafdata,void *multirootdata)
134   PetscAttrMPIPointerWithType(3,2) PetscAttrMPIPointerWithType(4,2);
135 PETSC_EXTERN PetscErrorCode PetscSFGatherEnd(PetscSF,MPI_Datatype,const void *leafdata,void *multirootdata)
136   PetscAttrMPIPointerWithType(3,2) PetscAttrMPIPointerWithType(4,2);
137 /* Distribute distinct values to each leaf from roots */
138 PETSC_EXTERN PetscErrorCode PetscSFScatterBegin(PetscSF,MPI_Datatype,const void *multirootdata,void *leafdata)
139   PetscAttrMPIPointerWithType(3,2) PetscAttrMPIPointerWithType(4,2);
140 PETSC_EXTERN PetscErrorCode PetscSFScatterEnd(PetscSF,MPI_Datatype,const void *multirootdata,void *leafdata)
141   PetscAttrMPIPointerWithType(3,2) PetscAttrMPIPointerWithType(4,2);
142 
143 #endif
144