Actual source code: sfbasic.c
petsc-master 2020-08-09
2: #include <../src/vec/is/sf/impls/basic/sfbasic.h>
3: #include <../src/vec/is/sf/impls/basic/sfpack.h>
5: /*===================================================================================*/
6: /* SF public interface implementations */
7: /*===================================================================================*/
8: PETSC_INTERN PetscErrorCode PetscSFSetUp_Basic(PetscSF sf)
9: {
11: PetscSF_Basic *bas = (PetscSF_Basic*)sf->data;
12: PetscInt *rlengths,*ilengths,i;
13: PetscMPIInt rank,niranks,*iranks,tag;
14: MPI_Comm comm;
15: MPI_Group group;
16: MPI_Request *rootreqs,*leafreqs;
19: MPI_Comm_group(PETSC_COMM_SELF,&group);
20: PetscSFSetUpRanks(sf,group);
21: MPI_Group_free(&group);
22: PetscObjectGetComm((PetscObject)sf,&comm);
23: PetscObjectGetNewTag((PetscObject)sf,&tag);
24: MPI_Comm_rank(comm,&rank);
25: /*
26: * Inform roots about how many leaves and from which ranks
27: */
28: PetscMalloc1(sf->nranks,&rlengths);
29: /* Determine number, sending ranks and length of incoming */
30: for (i=0; i<sf->nranks; i++) {
31: rlengths[i] = sf->roffset[i+1] - sf->roffset[i]; /* Number of roots referenced by my leaves; for rank sf->ranks[i] */
32: }
33: PetscCommBuildTwoSided(comm,1,MPIU_INT,sf->nranks-sf->ndranks,sf->ranks+sf->ndranks,rlengths+sf->ndranks,&niranks,&iranks,(void**)&ilengths);
35: /* Sort iranks. See use of VecScatterGetRemoteOrdered_Private() in MatGetBrowsOfAoCols_MPIAIJ() on why.
36: We could sort ranks there at the price of allocating extra working arrays. Presumably, niranks is
37: small and the sorting is cheap.
38: */
39: PetscSortMPIIntWithIntArray(niranks,iranks,ilengths);
41: /* Partition into distinguished and non-distinguished incoming ranks */
42: bas->ndiranks = sf->ndranks;
43: bas->niranks = bas->ndiranks + niranks;
44: PetscMalloc2(bas->niranks,&bas->iranks,bas->niranks+1,&bas->ioffset);
45: bas->ioffset[0] = 0;
46: for (i=0; i<bas->ndiranks; i++) {
47: bas->iranks[i] = sf->ranks[i];
48: bas->ioffset[i+1] = bas->ioffset[i] + rlengths[i];
49: }
50: if (bas->ndiranks > 1 || (bas->ndiranks == 1 && bas->iranks[0] != rank)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Broken setup for shared ranks");
51: for ( ; i<bas->niranks; i++) {
52: bas->iranks[i] = iranks[i-bas->ndiranks];
53: bas->ioffset[i+1] = bas->ioffset[i] + ilengths[i-bas->ndiranks];
54: }
55: bas->itotal = bas->ioffset[i];
56: PetscFree(rlengths);
57: PetscFree(iranks);
58: PetscFree(ilengths);
60: /* Send leaf identities to roots */
61: PetscMalloc1(bas->itotal,&bas->irootloc);
62: PetscMalloc2(bas->niranks-bas->ndiranks,&rootreqs,sf->nranks-sf->ndranks,&leafreqs);
63: for (i=bas->ndiranks; i<bas->niranks; i++) {
64: MPI_Irecv(bas->irootloc+bas->ioffset[i],bas->ioffset[i+1]-bas->ioffset[i],MPIU_INT,bas->iranks[i],tag,comm,&rootreqs[i-bas->ndiranks]);
65: }
66: for (i=0; i<sf->nranks; i++) {
67: PetscMPIInt npoints;
68: PetscMPIIntCast(sf->roffset[i+1] - sf->roffset[i],&npoints);
69: if (i < sf->ndranks) {
70: if (sf->ranks[i] != rank) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Cannot interpret distinguished leaf rank");
71: if (bas->iranks[0] != rank) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Cannot interpret distinguished root rank");
72: if (npoints != bas->ioffset[1]-bas->ioffset[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Distinguished rank exchange has mismatched lengths");
73: PetscArraycpy(bas->irootloc+bas->ioffset[0],sf->rremote+sf->roffset[i],npoints);
74: continue;
75: }
76: MPI_Isend(sf->rremote+sf->roffset[i],npoints,MPIU_INT,sf->ranks[i],tag,comm,&leafreqs[i-sf->ndranks]);
77: }
78: MPI_Waitall(bas->niranks-bas->ndiranks,rootreqs,MPI_STATUSES_IGNORE);
79: MPI_Waitall(sf->nranks-sf->ndranks,leafreqs,MPI_STATUSES_IGNORE);
80: PetscFree2(rootreqs,leafreqs);
82: sf->nleafreqs = sf->nranks - sf->ndranks;
83: bas->nrootreqs = bas->niranks - bas->ndiranks;
84: sf->persistent = PETSC_TRUE;
86: /* Setup fields related to packing */
87: PetscSFSetUpPackFields(sf);
88: return(0);
89: }
91: PETSC_INTERN PetscErrorCode PetscSFReset_Basic(PetscSF sf)
92: {
93: PetscErrorCode ierr;
94: PetscSF_Basic *bas = (PetscSF_Basic*)sf->data;
97: if (bas->inuse) SETERRQ(PetscObjectComm((PetscObject)sf),PETSC_ERR_ARG_WRONGSTATE,"Outstanding operation has not been completed");
98: PetscFree2(bas->iranks,bas->ioffset);
99: PetscFree(bas->irootloc);
100: #if defined(PETSC_HAVE_CUDA)
101: {
102: PetscInt i;
103: for (i=0; i<2; i++) {if (bas->irootloc_d[i]) {cudaError_t err = cudaFree(bas->irootloc_d[i]);CHKERRCUDA(err);bas->irootloc_d[i]=NULL;}}
104: }
105: #endif
106: PetscSFLinkDestroy(sf,&bas->avail);
107: PetscSFResetPackFields(sf);
108: return(0);
109: }
111: PETSC_INTERN PetscErrorCode PetscSFDestroy_Basic(PetscSF sf)
112: {
116: PetscSFReset_Basic(sf);
117: PetscFree(sf->data);
118: return(0);
119: }
121: PETSC_INTERN PetscErrorCode PetscSFView_Basic(PetscSF sf,PetscViewer viewer)
122: {
124: PetscBool iascii;
127: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);
128: if (iascii) {PetscViewerASCIIPrintf(viewer," sort=%s\n",sf->rankorder ? "rank-order" : "unordered");}
129: return(0);
130: }
132: static PetscErrorCode PetscSFBcastAndOpBegin_Basic(PetscSF sf,MPI_Datatype unit,PetscMemType rootmtype,const void *rootdata,PetscMemType leafmtype,void *leafdata,MPI_Op op)
133: {
134: PetscErrorCode ierr;
135: PetscSFLink link = NULL;
136: MPI_Request *rootreqs = NULL,*leafreqs = NULL;
137: PetscSF_Basic *bas = (PetscSF_Basic*)sf->data;
140: /* Create a communication link, which provides buffers & MPI requests etc */
141: PetscSFLinkCreate(sf,unit,rootmtype,rootdata,leafmtype,leafdata,op,PETSCSF_BCAST,&link);
142: /* Get MPI requests from the link. We do not need buffers explicitly since we use persistent MPI */
143: PetscSFLinkGetMPIBuffersAndRequests(sf,link,PETSCSF_../../../../../..2LEAF,NULL,NULL,&rootreqs,&leafreqs);
144: /* Post Irecv for remote */
145: MPI_Startall_irecv(sf->leafbuflen[PETSCSF_REMOTE],unit,sf->nleafreqs,leafreqs);
146: /* Pack rootdata and do Isend for remote */
147: PetscSFLinkPackRootData(sf,link,PETSCSF_REMOTE,rootdata);
148: MPI_Startall_isend(bas->rootbuflen[PETSCSF_REMOTE],unit,bas->nrootreqs,rootreqs);
149: /* Do local BcastAndOp, which overlaps with the irecv/isend above */
150: PetscSFLinkBcastAndOpLocal(sf,link,rootdata,leafdata,op);
151: return(0);
152: }
154: PETSC_INTERN PetscErrorCode PetscSFBcastAndOpEnd_Basic(PetscSF sf,MPI_Datatype unit,const void *rootdata,void *leafdata,MPI_Op op)
155: {
156: PetscErrorCode ierr;
157: PetscSFLink link = NULL;
160: /* Retrieve the link used in XxxBegin() with root/leafdata as key */
161: PetscSFLinkGetInUse(sf,unit,rootdata,leafdata,PETSC_OWN_POINTER,&link);
162: /* Wait for the completion of mpi */
163: PetscSFLinkMPIWaitall(sf,link,PETSCSF_../../../../../..2LEAF);
164: /* Unpack leafdata and reclaim the link */
165: PetscSFLinkUnpackLeafData(sf,link,PETSCSF_REMOTE,leafdata,op);
166: PetscSFLinkReclaim(sf,&link);
167: return(0);
168: }
170: /* Shared by ReduceBegin and FetchAndOpBegin */
171: PETSC_STATIC_INLINE PetscErrorCode PetscSFLeafToRootBegin_Basic(PetscSF sf,MPI_Datatype unit,PetscMemType leafmtype,const void *leafdata,PetscMemType rootmtype,void *rootdata,MPI_Op op,PetscSFOperation sfop,PetscSFLink *out)
172: {
173: PetscErrorCode ierr;
174: PetscSFLink link;
175: PetscSF_Basic *bas = (PetscSF_Basic*)sf->data;
176: MPI_Request *rootreqs = NULL,*leafreqs = NULL;
179: PetscSFLinkCreate(sf,unit,rootmtype,rootdata,leafmtype,leafdata,op,sfop,&link);
180: PetscSFLinkGetMPIBuffersAndRequests(sf,link,PETSCSF_LEAF2../../../../../..,NULL,NULL,&rootreqs,&leafreqs);
181: MPI_Startall_irecv(bas->rootbuflen[PETSCSF_REMOTE],unit,bas->nrootreqs,rootreqs);
182: PetscSFLinkPackLeafData(sf,link,PETSCSF_REMOTE,leafdata);
183: MPI_Startall_isend(sf->leafbuflen[PETSCSF_REMOTE],unit,sf->nleafreqs,leafreqs);
184: *out = link;
185: return(0);
186: }
188: /* leaf -> root with reduction */
189: static PetscErrorCode PetscSFReduceBegin_Basic(PetscSF sf,MPI_Datatype unit,PetscMemType leafmtype,const void *leafdata,PetscMemType rootmtype,void *rootdata,MPI_Op op)
190: {
191: PetscErrorCode ierr;
192: PetscSFLink link = NULL;
195: PetscSFLeafToRootBegin_Basic(sf,unit,leafmtype,leafdata,rootmtype,rootdata,op,PETSCSF_REDUCE,&link);
196: PetscSFLinkReduceLocal(sf,link,leafdata,rootdata,op);
197: return(0);
198: }
200: PETSC_INTERN PetscErrorCode PetscSFReduceEnd_Basic(PetscSF sf,MPI_Datatype unit,const void *leafdata,void *rootdata,MPI_Op op)
201: {
202: PetscErrorCode ierr;
203: PetscSFLink link = NULL;
206: PetscSFLinkGetInUse(sf,unit,rootdata,leafdata,PETSC_OWN_POINTER,&link);
207: PetscSFLinkMPIWaitall(sf,link,PETSCSF_LEAF2../../../../../..);
208: PetscSFLinkUnpackRootData(sf,link,PETSCSF_REMOTE,rootdata,op);
209: PetscSFLinkReclaim(sf,&link);
210: return(0);
211: }
213: PETSC_INTERN PetscErrorCode PetscSFFetchAndOpBegin_Basic(PetscSF sf,MPI_Datatype unit,PetscMemType rootmtype,void *rootdata,PetscMemType leafmtype,const void *leafdata,void *leafupdate,MPI_Op op)
214: {
215: PetscErrorCode ierr;
216: PetscSFLink link = NULL;
219: PetscSFLeafToRootBegin_Basic(sf,unit,leafmtype,leafdata,rootmtype,rootdata,op,PETSCSF_FETCH,&link);
220: PetscSFLinkFetchAndOpLocal(sf,link,rootdata,leafdata,leafupdate,op);
221: return(0);
222: }
224: static PetscErrorCode PetscSFFetchAndOpEnd_Basic(PetscSF sf,MPI_Datatype unit,void *rootdata,const void *leafdata,void *leafupdate,MPI_Op op)
225: {
226: PetscErrorCode ierr;
227: PetscSFLink link = NULL;
228: MPI_Request *rootreqs = NULL,*leafreqs = NULL;
229: PetscSF_Basic *bas = (PetscSF_Basic*)sf->data;
232: PetscSFLinkGetInUse(sf,unit,rootdata,leafdata,PETSC_OWN_POINTER,&link);
233: /* This implementation could be changed to unpack as receives arrive, at the cost of non-determinism */
234: PetscSFLinkMPIWaitall(sf,link,PETSCSF_LEAF2../../../../../..);
235: /* Do fetch-and-op, the (remote) update results are in rootbuf */
236: PetscSFLinkFetchRootData(sf,link,PETSCSF_REMOTE,rootdata,op);
238: /* Bcast rootbuf to leafupdate */
239: PetscSFLinkGetMPIBuffersAndRequests(sf,link,PETSCSF_../../../../../..2LEAF,NULL,NULL,&rootreqs,&leafreqs);
240: /* Post leaf receives and root sends */
241: MPI_Startall_irecv(sf->leafbuflen[PETSCSF_REMOTE],unit,sf->nleafreqs,leafreqs);
242: MPI_Startall_isend(bas->rootbuflen[PETSCSF_REMOTE],unit,bas->nrootreqs,rootreqs);
243: /* Unpack and insert fetched data into leaves */
244: PetscSFLinkMPIWaitall(sf,link,PETSCSF_../../../../../..2LEAF);
245: PetscSFLinkUnpackLeafData(sf,link,PETSCSF_REMOTE,leafupdate,MPIU_REPLACE);
246: PetscSFLinkReclaim(sf,&link);
247: return(0);
248: }
250: PETSC_INTERN PetscErrorCode PetscSFGetLeafRanks_Basic(PetscSF sf,PetscInt *niranks,const PetscMPIInt **iranks,const PetscInt **ioffset,const PetscInt **irootloc)
251: {
252: PetscSF_Basic *bas = (PetscSF_Basic*)sf->data;
255: if (niranks) *niranks = bas->niranks;
256: if (iranks) *iranks = bas->iranks;
257: if (ioffset) *ioffset = bas->ioffset;
258: if (irootloc) *irootloc = bas->irootloc;
259: return(0);
260: }
262: /* An optimized PetscSFCreateEmbeddedSF. We aggresively make use of the established communication on sf.
263: We need one bcast on sf, and no communication anymore to build the embedded sf. Note that selected[]
264: was sorted before calling the routine.
265: */
266: PETSC_INTERN PetscErrorCode PetscSFCreateEmbeddedSF_Basic(PetscSF sf,PetscInt nselected,const PetscInt *selected,PetscSF *newsf)
267: {
268: PetscSF esf;
269: PetscInt esf_nranks,esf_ndranks,*esf_roffset,*esf_rmine,*esf_rremote;
270: PetscInt i,j,p,q,nroots,esf_nleaves,*new_ilocal,nranks,ndranks,niranks,ndiranks,minleaf,maxleaf,maxlocal;
271: char *rootdata,*leafdata,*leafmem; /* Only stores 0 or 1, so we can save memory with char */
272: PetscMPIInt *esf_ranks;
273: const PetscMPIInt *ranks,*iranks;
274: const PetscInt *roffset,*rmine,*rremote,*ioffset,*irootloc;
275: PetscBool connected;
276: PetscSFNode *new_iremote;
277: PetscSF_Basic *bas;
278: PetscErrorCode ierr;
281: PetscSFCreate(PetscObjectComm((PetscObject)sf),&esf);
282: PetscSFSetType(esf,PETSCSFBASIC); /* This optimized routine can only create a basic sf */
284: /* Find out which leaves are still connected to roots in the embedded sf by doing a Bcast */
285: PetscSFGetGraph(sf,&nroots,NULL,NULL,NULL);
286: PetscSFGetLeafRange(sf,&minleaf,&maxleaf);
287: maxlocal = maxleaf - minleaf + 1;
288: PetscCalloc2(nroots,&rootdata,maxlocal,&leafmem);
289: leafdata = leafmem - minleaf;
290: /* Tag selected roots */
291: for (i=0; i<nselected; ++i) rootdata[selected[i]] = 1;
293: PetscSFBcastBegin(sf,MPI_CHAR,rootdata,leafdata);
294: PetscSFBcastEnd(sf,MPI_CHAR,rootdata,leafdata);
295: PetscSFGetLeafInfo_Basic(sf,&nranks,&ndranks,&ranks,&roffset,&rmine,&rremote); /* Get send info */
296: esf_nranks = esf_ndranks = esf_nleaves = 0;
297: for (i=0; i<nranks; i++) {
298: connected = PETSC_FALSE; /* Is this process still connected to this remote root rank? */
299: for (j=roffset[i]; j<roffset[i+1]; j++) {if (leafdata[rmine[j]]) {esf_nleaves++; connected = PETSC_TRUE;}}
300: if (connected) {esf_nranks++; if (i < ndranks) esf_ndranks++;}
301: }
303: /* Set graph of esf and also set up its outgoing communication (i.e., send info), which is usually done by PetscSFSetUpRanks */
304: PetscMalloc1(esf_nleaves,&new_ilocal);
305: PetscMalloc1(esf_nleaves,&new_iremote);
306: PetscMalloc4(esf_nranks,&esf_ranks,esf_nranks+1,&esf_roffset,esf_nleaves,&esf_rmine,esf_nleaves,&esf_rremote);
307: p = 0; /* Counter for connected root ranks */
308: q = 0; /* Counter for connected leaves */
309: esf_roffset[0] = 0;
310: for (i=0; i<nranks; i++) { /* Scan leaf data again to fill esf arrays */
311: connected = PETSC_FALSE;
312: for (j=roffset[i]; j<roffset[i+1]; j++) {
313: if (leafdata[rmine[j]]) {
314: esf_rmine[q] = new_ilocal[q] = rmine[j];
315: esf_rremote[q] = rremote[j];
316: new_iremote[q].index = rremote[j];
317: new_iremote[q].rank = ranks[i];
318: connected = PETSC_TRUE;
319: q++;
320: }
321: }
322: if (connected) {
323: esf_ranks[p] = ranks[i];
324: esf_roffset[p+1] = q;
325: p++;
326: }
327: }
329: /* SetGraph internally resets the SF, so we only set its fields after the call */
330: PetscSFSetGraph(esf,nroots,esf_nleaves,new_ilocal,PETSC_OWN_POINTER,new_iremote,PETSC_OWN_POINTER);
331: esf->nranks = esf_nranks;
332: esf->ndranks = esf_ndranks;
333: esf->ranks = esf_ranks;
334: esf->roffset = esf_roffset;
335: esf->rmine = esf_rmine;
336: esf->rremote = esf_rremote;
337: esf->nleafreqs = esf_nranks - esf_ndranks;
339: /* Set up the incoming communication (i.e., recv info) stored in esf->data, which is usually done by PetscSFSetUp_Basic */
340: bas = (PetscSF_Basic*)esf->data;
341: PetscSFGetRootInfo_Basic(sf,&niranks,&ndiranks,&iranks,&ioffset,&irootloc); /* Get recv info */
342: /* Embedded sf always has simpler communication than the original one. We might allocate longer arrays than needed here. But we
343: we do not care since these arrays are usually short. The benefit is we can fill these arrays by just parsing irootloc once.
344: */
345: PetscMalloc2(niranks,&bas->iranks,niranks+1,&bas->ioffset);
346: PetscMalloc1(ioffset[niranks],&bas->irootloc);
347: bas->niranks = bas->ndiranks = bas->ioffset[0] = 0;
348: p = 0; /* Counter for connected leaf ranks */
349: q = 0; /* Counter for connected roots */
350: for (i=0; i<niranks; i++) {
351: connected = PETSC_FALSE; /* Is the current process still connected to this remote leaf rank? */
352: for (j=ioffset[i]; j<ioffset[i+1]; j++) {
353: if (rootdata[irootloc[j]]) {
354: bas->irootloc[q++] = irootloc[j];
355: connected = PETSC_TRUE;
356: }
357: }
358: if (connected) {
359: bas->niranks++;
360: if (i<ndiranks) bas->ndiranks++; /* Note that order of ranks (including distinguished ranks) is kept */
361: bas->iranks[p] = iranks[i];
362: bas->ioffset[p+1] = q;
363: p++;
364: }
365: }
366: bas->itotal = q;
367: bas->nrootreqs = bas->niranks - bas->ndiranks;
368: esf->persistent = PETSC_TRUE;
369: /* Setup packing related fields */
370: PetscSFSetUpPackFields(esf);
372: esf->setupcalled = PETSC_TRUE; /* We have done setup ourselves! */
373: PetscFree2(rootdata,leafmem);
374: *newsf = esf;
375: return(0);
376: }
378: PETSC_EXTERN PetscErrorCode PetscSFCreate_Basic(PetscSF sf)
379: {
380: PetscSF_Basic *dat;
384: sf->ops->SetUp = PetscSFSetUp_Basic;
385: sf->ops->Reset = PetscSFReset_Basic;
386: sf->ops->Destroy = PetscSFDestroy_Basic;
387: sf->ops->View = PetscSFView_Basic;
388: sf->ops->BcastAndOpBegin = PetscSFBcastAndOpBegin_Basic;
389: sf->ops->BcastAndOpEnd = PetscSFBcastAndOpEnd_Basic;
390: sf->ops->ReduceBegin = PetscSFReduceBegin_Basic;
391: sf->ops->ReduceEnd = PetscSFReduceEnd_Basic;
392: sf->ops->FetchAndOpBegin = PetscSFFetchAndOpBegin_Basic;
393: sf->ops->FetchAndOpEnd = PetscSFFetchAndOpEnd_Basic;
394: sf->ops->GetLeafRanks = PetscSFGetLeafRanks_Basic;
395: sf->ops->CreateEmbeddedSF = PetscSFCreateEmbeddedSF_Basic;
397: PetscNewLog(sf,&dat);
398: sf->data = (void*)dat;
399: return(0);
400: }