Actual source code: sfwindow.c
petsc-3.15.0 2021-03-30
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      1: #include <petsc/private/sfimpl.h>

      3: typedef struct _n_PetscSFDataLink *PetscSFDataLink;
      4: typedef struct _n_PetscSFWinLink  *PetscSFWinLink;

      6: typedef struct {
      7:   PetscSFWindowSyncType   sync;   /* FENCE, LOCK, or ACTIVE synchronization */
      8:   PetscSFDataLink         link;   /* List of MPI data types, lazily constructed for each data type */
      9:   PetscSFWinLink          wins;   /* List of active windows */
     10:   PetscSFWindowFlavorType flavor; /* Current PETSCSF_WINDOW_FLAVOR_ */
     11:   PetscSF                 dynsf;
     12:   MPI_Info                info;
     13: } PetscSF_Window;

     15: struct _n_PetscSFDataLink {
     16:   MPI_Datatype    unit;
     17:   MPI_Datatype    *mine;
     18:   MPI_Datatype    *remote;
     19:   PetscSFDataLink next;
     20: };

     22: struct _n_PetscSFWinLink {
     23:   PetscBool               inuse;
     24:   size_t                  bytes;
     25:   void                    *addr;
     26:   void                    *paddr;
     27:   MPI_Win                 win;
     28:   MPI_Request             *reqs;
     29:   PetscSFWindowFlavorType flavor;
     30:   MPI_Aint                *dyn_target_addr;
     31:   PetscBool               epoch;
     32:   PetscSFWinLink          next;
     33: };

     35: const char *const PetscSFWindowSyncTypes[] = {"FENCE","LOCK","ACTIVE","PetscSFWindowSyncType","PETSCSF_WINDOW_SYNC_",NULL};
     36: const char *const PetscSFWindowFlavorTypes[] = {"CREATE","DYNAMIC","ALLOCATE","SHARED","PetscSFWindowFlavorType","PETSCSF_WINDOW_FLAVOR_",NULL};

     38: /* Built-in MPI_Ops act elementwise inside MPI_Accumulate, but cannot be used with composite types inside collectives (MPIU_Allreduce) */
     39: static PetscErrorCode PetscSFWindowOpTranslate(MPI_Op *op)
     40: {
     42:   if (*op == MPIU_SUM) *op = MPI_SUM;
     43:   else if (*op == MPIU_MAX) *op = MPI_MAX;
     44:   else if (*op == MPIU_MIN) *op = MPI_MIN;
     45:   return(0);
     46: }

     48: /*@C
     49:    PetscSFWindowGetDataTypes - gets composite local and remote data types for each rank

     51:    Not Collective

     53:    Input Arguments:
     54: +  sf - star forest
     55: -  unit - data type for each node

     57:    Output Arguments:
     58: +  localtypes - types describing part of local leaf buffer referencing each remote rank
     59: -  remotetypes - types describing part of remote root buffer referenced for each remote rank

     61:    Level: developer

     63: .seealso: PetscSFSetGraph(), PetscSFView()
     64: @*/
     65: static PetscErrorCode PetscSFWindowGetDataTypes(PetscSF sf,MPI_Datatype unit,const MPI_Datatype **localtypes,const MPI_Datatype **remotetypes)
     66: {
     67:   PetscSF_Window    *w = (PetscSF_Window*)sf->data;
     68:   PetscErrorCode    ierr;
     69:   PetscSFDataLink   link;
     70:   PetscInt          i,nranks;
     71:   const PetscInt    *roffset,*rmine,*rremote;
     72:   const PetscMPIInt *ranks;

     75:   /* Look for types in cache */
     76:   for (link=w->link; link; link=link->next) {
     77:     PetscBool match;
     78:     MPIPetsc_Type_compare(unit,link->unit,&match);
     79:     if (match) {
     80:       *localtypes  = link->mine;
     81:       *remotetypes = link->remote;
     82:       return(0);
     83:     }
     84:   }

     86:   /* Create new composite types for each send rank */
     87:   PetscSFGetRootRanks(sf,&nranks,&ranks,&roffset,&rmine,&rremote);
     88:   PetscNew(&link);
     89:   MPI_Type_dup(unit,&link->unit);
     90:   PetscMalloc2(nranks,&link->mine,nranks,&link->remote);
     91:   for (i=0; i<nranks; i++) {
     92:     PetscInt    rcount = roffset[i+1] - roffset[i];
     93:     PetscMPIInt *rmine,*rremote;
     94: #if !defined(PETSC_USE_64BIT_INDICES)
     95:     rmine   = sf->rmine + sf->roffset[i];
     96:     rremote = sf->rremote + sf->roffset[i];
     97: #else
     98:     PetscInt j;
     99:     PetscMalloc2(rcount,&rmine,rcount,&rremote);
    100:     for (j=0; j<rcount; j++) {
    101:       PetscMPIIntCast(sf->rmine[sf->roffset[i]+j],rmine+j);
    102:       PetscMPIIntCast(sf->rremote[sf->roffset[i]+j],rremote+j);
    103:     }
    104: #endif

    106:     MPI_Type_create_indexed_block(rcount,1,rmine,link->unit,&link->mine[i]);
    107:     MPI_Type_create_indexed_block(rcount,1,rremote,link->unit,&link->remote[i]);
    108: #if defined(PETSC_USE_64BIT_INDICES)
    109:     PetscFree2(rmine,rremote);
    110: #endif
    111:     MPI_Type_commit(&link->mine[i]);
    112:     MPI_Type_commit(&link->remote[i]);
    113:   }
    114:   link->next = w->link;
    115:   w->link    = link;

    117:   *localtypes  = link->mine;
    118:   *remotetypes = link->remote;
    119:   return(0);
    120: }

    122: /*@C
    123:    PetscSFWindowSetFlavorType - Set flavor type for MPI_Win creation

    125:    Logically Collective

    127:    Input Arguments:
    128: +  sf - star forest for communication
    129: -  flavor - flavor type

    131:    Options Database Key:
    132: .  -sf_window_flavor <flavor> - sets the flavor type CREATE, DYNAMIC, ALLOCATE or SHARED (see PetscSFWindowFlavorType)

    134:    Level: advanced

    136:    Notes: Windows reusage follow this rules:

    138:      PETSCSF_WINDOW_FLAVOR_CREATE: creates a new window every time, uses MPI_Win_create

    140:      PETSCSF_WINDOW_FLAVOR_DYNAMIC: uses MPI_Win_create_dynamic/MPI_Win_attach and tries to reuse windows by comparing the root array. Intended to be used on repeated applications of the same SF, e.g.
    141:        for i=1 to K
    142:          PetscSFOperationBegin(rootdata1,leafdata_whatever);
    143:          PetscSFOperationEnd(rootdata1,leafdata_whatever);
    144:          ...
    145:          PetscSFOperationBegin(rootdataN,leafdata_whatever);
    146:          PetscSFOperationEnd(rootdataN,leafdata_whatever);
    147:        endfor
    148:        The following pattern will instead raise an error
    149:          PetscSFOperationBegin(rootdata1,leafdata_whatever);
    150:          PetscSFOperationEnd(rootdata1,leafdata_whatever);
    151:          PetscSFOperationBegin(rank ? rootdata1 : rootdata2,leafdata_whatever);
    152:          PetscSFOperationEnd(rank ? rootdata1 : rootdata2,leafdata_whatever);

    154:      PETSCSF_WINDOW_FLAVOR_ALLOCATE: uses MPI_Win_allocate, reuses any pre-existing window which fits the data and it is not in use

    156:      PETSCSF_WINDOW_FLAVOR_SHARED: uses MPI_Win_allocate_shared, reusage policy as for PETSCSF_WINDOW_FLAVOR_ALLOCATE

    158: .seealso: PetscSFSetFromOptions(), PetscSFWindowGetFlavorType()
    159: @*/
    160: PetscErrorCode PetscSFWindowSetFlavorType(PetscSF sf,PetscSFWindowFlavorType flavor)
    161: {

    167:   PetscTryMethod(sf,"PetscSFWindowSetFlavorType_C",(PetscSF,PetscSFWindowFlavorType),(sf,flavor));
    168:   return(0);
    169: }

    171: static PetscErrorCode PetscSFWindowSetFlavorType_Window(PetscSF sf,PetscSFWindowFlavorType flavor)
    172: {
    173:   PetscSF_Window *w = (PetscSF_Window*)sf->data;

    176:   w->flavor = flavor;
    177:   return(0);
    178: }

    180: /*@C
    181:    PetscSFWindowGetFlavorType - Get flavor type for PetscSF communication

    183:    Logically Collective

    185:    Input Argument:
    186: .  sf - star forest for communication

    188:    Output Argument:
    189: .  flavor - flavor type

    191:    Level: advanced

    193: .seealso: PetscSFSetFromOptions(), PetscSFWindowSetFlavorType()
    194: @*/
    195: PetscErrorCode PetscSFWindowGetFlavorType(PetscSF sf,PetscSFWindowFlavorType *flavor)
    196: {

    202:   PetscUseMethod(sf,"PetscSFWindowGetFlavorType_C",(PetscSF,PetscSFWindowFlavorType*),(sf,flavor));
    203:   return(0);
    204: }

    206: static PetscErrorCode PetscSFWindowGetFlavorType_Window(PetscSF sf,PetscSFWindowFlavorType *flavor)
    207: {
    208:   PetscSF_Window *w = (PetscSF_Window*)sf->data;

    211:   *flavor = w->flavor;
    212:   return(0);
    213: }

    215: /*@C
    216:    PetscSFWindowSetSyncType - Set synchronization type for PetscSF communication

    218:    Logically Collective

    220:    Input Arguments:
    221: +  sf - star forest for communication
    222: -  sync - synchronization type

    224:    Options Database Key:
    225: .  -sf_window_sync <sync> - sets the synchronization type FENCE, LOCK, or ACTIVE (see PetscSFWindowSyncType)

    227:    Level: advanced

    229: .seealso: PetscSFSetFromOptions(), PetscSFWindowGetSyncType()
    230: @*/
    231: PetscErrorCode PetscSFWindowSetSyncType(PetscSF sf,PetscSFWindowSyncType sync)
    232: {

    238:   PetscTryMethod(sf,"PetscSFWindowSetSyncType_C",(PetscSF,PetscSFWindowSyncType),(sf,sync));
    239:   return(0);
    240: }

    242: static PetscErrorCode PetscSFWindowSetSyncType_Window(PetscSF sf,PetscSFWindowSyncType sync)
    243: {
    244:   PetscSF_Window *w = (PetscSF_Window*)sf->data;

    247:   w->sync = sync;
    248:   return(0);
    249: }

    251: /*@C
    252:    PetscSFWindowGetSyncType - Get synchronization type for PetscSF communication

    254:    Logically Collective

    256:    Input Argument:
    257: .  sf - star forest for communication

    259:    Output Argument:
    260: .  sync - synchronization type

    262:    Level: advanced

    264: .seealso: PetscSFSetFromOptions(), PetscSFWindowSetSyncType()
    265: @*/
    266: PetscErrorCode PetscSFWindowGetSyncType(PetscSF sf,PetscSFWindowSyncType *sync)
    267: {

    273:   PetscUseMethod(sf,"PetscSFWindowGetSyncType_C",(PetscSF,PetscSFWindowSyncType*),(sf,sync));
    274:   return(0);
    275: }

    277: static PetscErrorCode PetscSFWindowGetSyncType_Window(PetscSF sf,PetscSFWindowSyncType *sync)
    278: {
    279:   PetscSF_Window *w = (PetscSF_Window*)sf->data;

    282:   *sync = w->sync;
    283:   return(0);
    284: }

    286: /*@C
    287:    PetscSFWindowSetInfo - Set the MPI_Info handle that will be used for subsequent windows allocation

    289:    Logically Collective

    291:    Input Argument:
    292: +  sf - star forest for communication
    293: -  info - MPI_Info handle

    295:    Level: advanced

    297:    Notes: the info handle is duplicated with a call to MPI_Info_dup unless info = MPI_INFO_NULL.

    299: .seealso: PetscSFSetFromOptions(), PetscSFWindowGetInfo()
    300: @*/
    301: PetscErrorCode PetscSFWindowSetInfo(PetscSF sf,MPI_Info info)
    302: {

    307:   PetscTryMethod(sf,"PetscSFWindowSetInfo_C",(PetscSF,MPI_Info),(sf,info));
    308:   return(0);
    309: }

    311: static PetscErrorCode PetscSFWindowSetInfo_Window(PetscSF sf,MPI_Info info)
    312: {
    313:   PetscSF_Window *w = (PetscSF_Window*)sf->data;

    317:   if (w->info != MPI_INFO_NULL) {
    318:     MPI_Info_free(&w->info);
    319:   }
    320:   if (info != MPI_INFO_NULL) {
    321:     MPI_Info_dup(info,&w->info);
    322:   }
    323:   return(0);
    324: }

    326: /*@C
    327:    PetscSFWindowGetInfo - Get the MPI_Info handle used for windows allocation

    329:    Logically Collective

    331:    Input Argument:
    332: .  sf - star forest for communication

    334:    Output Argument:
    335: .  info - MPI_Info handle

    337:    Level: advanced

    339:    Notes: if PetscSFWindowSetInfo() has not be called, this returns MPI_INFO_NULL

    341: .seealso: PetscSFSetFromOptions(), PetscSFWindowSetInfo()
    342: @*/
    343: PetscErrorCode PetscSFWindowGetInfo(PetscSF sf,MPI_Info *info)
    344: {

    350:   PetscUseMethod(sf,"PetscSFWindowGetInfo_C",(PetscSF,MPI_Info*),(sf,info));
    351:   return(0);
    352: }

    354: static PetscErrorCode PetscSFWindowGetInfo_Window(PetscSF sf,MPI_Info *info)
    355: {
    356:   PetscSF_Window *w = (PetscSF_Window*)sf->data;

    359:   *info = w->info;
    360:   return(0);
    361: }

    363: /*
    364:    PetscSFGetWindow - Get a window for use with a given data type

    366:    Collective on PetscSF

    368:    Input Arguments:
    369: +  sf - star forest
    370: .  unit - data type
    371: .  array - array to be sent
    372: .  sync - type of synchronization PetscSFWindowSyncType
    373: .  epoch - PETSC_TRUE to acquire the window and start an epoch, PETSC_FALSE to just acquire the window
    374: .  fenceassert - assert parameter for call to MPI_Win_fence(), if sync == PETSCSF_WINDOW_SYNC_FENCE
    375: .  postassert - assert parameter for call to MPI_Win_post(), if sync == PETSCSF_WINDOW_SYNC_ACTIVE
    376: -  startassert - assert parameter for call to MPI_Win_start(), if sync == PETSCSF_WINDOW_SYNC_ACTIVE

    378:    Output Arguments:
    379: +  target_disp - target_disp argument for RMA calls (significative for PETSCSF_WINDOW_FLAVOR_DYNAMIC only)
    380: +  reqs - array of requests (significative for sync == PETSCSF_WINDOW_SYNC_LOCK only)
    381: -  win - window

    383:    Level: developer
    384: .seealso: PetscSFGetRootRanks(), PetscSFWindowGetDataTypes()
    385: */
    386: static PetscErrorCode PetscSFGetWindow(PetscSF sf,MPI_Datatype unit,void *array,PetscSFWindowSyncType sync,PetscBool epoch,PetscMPIInt fenceassert,PetscMPIInt postassert,PetscMPIInt startassert,const MPI_Aint **target_disp, MPI_Request **reqs, MPI_Win *win)
    387: {
    388:   PetscSF_Window *w = (PetscSF_Window*)sf->data;
    390:   MPI_Aint       lb,lb_true,bytes,bytes_true;
    391:   PetscSFWinLink link;
    392:   MPI_Aint       winaddr;
    393:   PetscInt       nranks;
    394:   PetscBool      reuse = PETSC_FALSE, update = PETSC_FALSE;
    395:   PetscBool      dummy[2];
    396:   MPI_Aint       wsize;

    399:   MPI_Type_get_extent(unit,&lb,&bytes);
    400:   MPI_Type_get_true_extent(unit,&lb_true,&bytes_true);
    401:   if (lb != 0 || lb_true != 0) SETERRQ(PetscObjectComm((PetscObject)sf),PETSC_ERR_SUP,"No support for unit type with nonzero lower bound, write petsc-maint@mcs.anl.gov if you want this feature");
    402:   if (bytes != bytes_true) SETERRQ(PetscObjectComm((PetscObject)sf),PETSC_ERR_SUP,"No support for unit type with modified extent, write petsc-maint@mcs.anl.gov if you want this feature");
    403:   if (w->flavor != PETSCSF_WINDOW_FLAVOR_CREATE) reuse = PETSC_TRUE;
    404:   for (link=w->wins; reuse && link; link=link->next) {
    405:     PetscBool winok = PETSC_FALSE;
    406:     if (w->flavor != link->flavor) continue;
    407:     switch (w->flavor) {
    408:     case PETSCSF_WINDOW_FLAVOR_DYNAMIC: /* check available matching array, error if in use (we additionally check that the matching condition is the same across processes) */
    409:       if (array == link->addr) {
    410:         if (PetscDefined(USE_DEBUG)) {
    411:           dummy[0] = PETSC_TRUE;
    412:           dummy[1] = PETSC_TRUE;
    413:           MPI_Allreduce(MPI_IN_PLACE,dummy,1,MPIU_BOOL,MPI_LAND,PetscObjectComm((PetscObject)sf));
    414:           MPI_Allreduce(MPI_IN_PLACE,dummy+1,1,MPIU_BOOL,MPI_LOR ,PetscObjectComm((PetscObject)sf));
    415:           if (dummy[0] != dummy[1]) SETERRQ(PetscObjectComm((PetscObject)sf),PETSC_ERR_SUP,"PETSCSF_WINDOW_FLAVOR_DYNAMIC requires root pointers to be consistently used across the comm. Use PETSCSF_WINDOW_FLAVOR_CREATE or PETSCSF_WINDOW_FLAVOR_ALLOCATE instead");
    416:         }
    417:         if (link->inuse) SETERRQ(PetscObjectComm((PetscObject)sf),PETSC_ERR_PLIB,"Window in use");
    418:         if (epoch && link->epoch) SETERRQ(PetscObjectComm((PetscObject)sf),PETSC_ERR_PLIB,"Window epoch not finished");
    419:         winok = PETSC_TRUE;
    420:         link->paddr = array;
    421:       } else if (PetscDefined(USE_DEBUG)) {
    422:         dummy[0] = PETSC_FALSE;
    423:         dummy[1] = PETSC_FALSE;
    424:         MPI_Allreduce(MPI_IN_PLACE,dummy  ,1,MPIU_BOOL,MPI_LAND,PetscObjectComm((PetscObject)sf));
    425:         MPI_Allreduce(MPI_IN_PLACE,dummy+1,1,MPIU_BOOL,MPI_LOR ,PetscObjectComm((PetscObject)sf));
    426:         if (dummy[0] != dummy[1]) SETERRQ(PetscObjectComm((PetscObject)sf),PETSC_ERR_SUP,"PETSCSF_WINDOW_FLAVOR_DYNAMIC requires root pointers to be consistently used across the comm. Use PETSCSF_WINDOW_FLAVOR_CREATE or PETSCSF_WINDOW_FLAVOR_ALLOCATE instead");
    427:       }
    428:       break;
    429:     case PETSCSF_WINDOW_FLAVOR_ALLOCATE: /* check available by matching size, allocate if in use */
    430:     case PETSCSF_WINDOW_FLAVOR_SHARED:
    431:       if (!link->inuse && bytes == (MPI_Aint)link->bytes) {
    432:         update = PETSC_TRUE;
    433:         link->paddr = array;
    434:         winok = PETSC_TRUE;
    435:       }
    436:       break;
    437:     default: SETERRQ1(PetscObjectComm((PetscObject)sf),PETSC_ERR_SUP,"No support for flavor %s",PetscSFWindowFlavorTypes[w->flavor]);
    438:     }
    439:     if (winok) {
    440:       *win = link->win;
    441:       PetscInfo3(sf,"Reusing window %d of flavor %d for comm %d\n",link->win,link->flavor,PetscObjectComm((PetscObject)sf));
    442:       goto found;
    443:     }
    444:   }

    446:   wsize = (MPI_Aint)bytes*sf->nroots;
    447:   PetscNew(&link);
    448:   link->bytes           = bytes;
    449:   link->next            = w->wins;
    450:   link->flavor          = w->flavor;
    451:   link->dyn_target_addr = NULL;
    452:   link->reqs            = NULL;
    453:   w->wins               = link;
    454:   if (sync == PETSCSF_WINDOW_SYNC_LOCK) {
    455:     PetscInt i;

    457:     PetscMalloc1(sf->nranks,&link->reqs);
    458:     for (i = 0; i < sf->nranks; i++) link->reqs[i] = MPI_REQUEST_NULL;
    459:   }
    460:   switch (w->flavor) {
    461:   case PETSCSF_WINDOW_FLAVOR_CREATE:
    462:     MPI_Win_create(array,wsize,(PetscMPIInt)bytes,w->info,PetscObjectComm((PetscObject)sf),&link->win);
    463:     link->addr  = array;
    464:     link->paddr = array;
    465:     break;
    466:   case PETSCSF_WINDOW_FLAVOR_DYNAMIC:
    467:     MPI_Win_create_dynamic(w->info,PetscObjectComm((PetscObject)sf),&link->win);
    468: #if defined(PETSC_HAVE_OMPI_MAJOR_VERSION) /* some OpenMPI versions do not support MPI_Win_attach(win,NULL,0); */
    469:     MPI_Win_attach(link->win,wsize ? array : &ierr,wsize);
    470: #else
    471:     MPI_Win_attach(link->win,array,wsize);
    472: #endif
    473:     link->addr  = array;
    474:     link->paddr = array;
    475:     if (!w->dynsf) SETERRQ(PetscObjectComm((PetscObject)sf),PETSC_ERR_ORDER,"Must call PetscSFSetUp()");
    476:     PetscSFSetUp(w->dynsf);
    477:     PetscSFGetRootRanks(w->dynsf,&nranks,NULL,NULL,NULL,NULL);
    478:     PetscMalloc1(nranks,&link->dyn_target_addr);
    479:     MPI_Get_address(array,&winaddr);
    480:     PetscSFBcastBegin(w->dynsf,MPI_AINT,&winaddr,link->dyn_target_addr,MPI_REPLACE);
    481:     PetscSFBcastEnd(w->dynsf,MPI_AINT,&winaddr,link->dyn_target_addr,MPI_REPLACE);
    482:     break;
    483:   case PETSCSF_WINDOW_FLAVOR_ALLOCATE:
    484:     MPI_Win_allocate(wsize,(PetscMPIInt)bytes,w->info,PetscObjectComm((PetscObject)sf),&link->addr,&link->win);
    485:     update = PETSC_TRUE;
    486:     link->paddr = array;
    487:     break;
    488: #if defined(PETSC_HAVE_MPI_PROCESS_SHARED_MEMORY)
    489:   case PETSCSF_WINDOW_FLAVOR_SHARED:
    490:     MPI_Win_allocate_shared(wsize,(PetscMPIInt)bytes,w->info,PetscObjectComm((PetscObject)sf),&link->addr,&link->win);
    491:     update = PETSC_TRUE;
    492:     link->paddr = array;
    493:     break;
    494: #endif
    495:   default: SETERRQ1(PetscObjectComm((PetscObject)sf),PETSC_ERR_SUP,"No support for flavor %s",PetscSFWindowFlavorTypes[w->flavor]);
    496:   }
    497:   PetscInfo3(sf,"New window %d of flavor %d for comm %d\n",link->win,link->flavor,PetscObjectComm((PetscObject)sf));
    498:   *win = link->win;

    500: found:

    502:   if (target_disp) *target_disp = link->dyn_target_addr;
    503:   if (reqs) *reqs = link->reqs;
    504:   if (update) { /* locks are needed for the "separate" memory model only, the fence guaranties memory-synchronization */
    505:     PetscMPIInt rank;

    507:     MPI_Comm_rank(PetscObjectComm((PetscObject)sf),&rank);
    508:     if (sync == PETSCSF_WINDOW_SYNC_LOCK) {MPI_Win_lock(MPI_LOCK_EXCLUSIVE,rank,MPI_MODE_NOCHECK,*win);}
    509:     PetscMemcpy(link->addr,array,sf->nroots*bytes);
    510:     if (sync == PETSCSF_WINDOW_SYNC_LOCK) {
    511:       MPI_Win_unlock(rank,*win);
    512:       MPI_Win_fence(0,*win);
    513:     }
    514:   }
    515:   link->inuse = PETSC_TRUE;
    516:   link->epoch = epoch;
    517:   if (epoch) {
    518:     switch (sync) {
    519:     case PETSCSF_WINDOW_SYNC_FENCE:
    520:       MPI_Win_fence(fenceassert,*win);
    521:       break;
    522:     case PETSCSF_WINDOW_SYNC_LOCK: /* Handled outside */
    523:       break;
    524:     case PETSCSF_WINDOW_SYNC_ACTIVE: {
    525:       MPI_Group   ingroup,outgroup;
    526:       PetscMPIInt isize,osize;

    528:       /* OpenMPI 4.0.2 with btl=vader does not like calling
    529:          - MPI_Win_complete when ogroup is empty
    530:          - MPI_Win_wait when igroup is empty
    531:          So, we do not even issue the corresponding start and post calls
    532:          The MPI standard (Sec. 11.5.2 of MPI 3.1) only requires that
    533:          start(outgroup) has a matching post(ingroup)
    534:          and this is guaranteed by PetscSF
    535:       */
    536:       PetscSFGetGroups(sf,&ingroup,&outgroup);
    537:       MPI_Group_size(ingroup,&isize);
    538:       MPI_Group_size(outgroup,&osize);
    539:       if (isize) {MPI_Win_post(ingroup,postassert,*win);}
    540:       if (osize) {MPI_Win_start(outgroup,startassert,*win);}
    541:     } break;
    542:     default: SETERRQ(PetscObjectComm((PetscObject)sf),PETSC_ERR_PLIB,"Unknown synchronization type");
    543:     }
    544:   }
    545:   return(0);
    546: }

    548: /*
    549:    PetscSFFindWindow - Finds a window that is already in use

    551:    Not Collective

    553:    Input Arguments:
    554: +  sf - star forest
    555: .  unit - data type
    556: -  array - array with which the window is associated

    558:    Output Arguments:
    559: +  win - window
    560: -  reqs - outstanding requests associated to the window

    562:    Level: developer

    564: .seealso: PetscSFGetWindow(), PetscSFRestoreWindow()
    565: */
    566: static PetscErrorCode PetscSFFindWindow(PetscSF sf,MPI_Datatype unit,const void *array,MPI_Win *win,MPI_Request **reqs)
    567: {
    568:   PetscSF_Window *w = (PetscSF_Window*)sf->data;
    569:   PetscSFWinLink link;

    573:   *win = MPI_WIN_NULL;
    574:   for (link=w->wins; link; link=link->next) {
    575:     if (array == link->paddr) {
    576:       PetscInfo3(sf,"Window %d of flavor %d for comm %d\n",link->win,link->flavor,PetscObjectComm((PetscObject)sf));
    577:       *win = link->win;
    578:       *reqs = link->reqs;
    579:       return(0);
    580:     }
    581:   }
    582:   SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Requested window not in use");
    583: }

    585: /*
    586:    PetscSFRestoreWindow - Restores a window obtained with PetscSFGetWindow()

    588:    Collective

    590:    Input Arguments:
    591: +  sf - star forest
    592: .  unit - data type
    593: .  array - array associated with window
    594: .  sync - type of synchronization PetscSFWindowSyncType
    595: .  epoch - close an epoch, must match argument to PetscSFGetWindow()
    596: .  update - if we have to update the local window array
    597: -  win - window

    599:    Level: developer

    601: .seealso: PetscSFFindWindow()
    602: */
    603: static PetscErrorCode PetscSFRestoreWindow(PetscSF sf,MPI_Datatype unit,void *array,PetscSFWindowSyncType sync,PetscBool epoch,PetscMPIInt fenceassert,PetscBool update,MPI_Win *win)
    604: {
    605:   PetscSF_Window          *w = (PetscSF_Window*)sf->data;
    606:   PetscErrorCode          ierr;
    607:   PetscSFWinLink          *p,link;
    608:   PetscBool               reuse = PETSC_FALSE;
    609:   PetscSFWindowFlavorType flavor;
    610:   void*                   laddr;
    611:   size_t                  bytes;

    614:   for (p=&w->wins; *p; p=&(*p)->next) {
    615:     link = *p;
    616:     if (*win == link->win) {
    617:       if (array != link->paddr) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Matched window, but not array");
    618:       if (epoch != link->epoch) {
    619:         if (epoch) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"No epoch to end");
    620:         else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Restoring window without ending epoch");
    621:       }
    622:       laddr = link->addr;
    623:       flavor = link->flavor;
    624:       bytes = link->bytes;
    625:       if (flavor != PETSCSF_WINDOW_FLAVOR_CREATE) reuse = PETSC_TRUE;
    626:       else { *p = link->next; update = PETSC_FALSE; } /* remove from list */
    627:       goto found;
    628:     }
    629:   }
    630:   SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Requested window not in use");

    632: found:
    633:   PetscInfo3(sf,"Window %d of flavor %d for comm %d\n",link->win,link->flavor,PetscObjectComm((PetscObject)sf));
    634:   if (epoch) {
    635:     switch (sync) {
    636:     case PETSCSF_WINDOW_SYNC_FENCE:
    637:       MPI_Win_fence(fenceassert,*win);
    638:       break;
    639:     case PETSCSF_WINDOW_SYNC_LOCK: /* Handled outside */
    640:       break;
    641:     case PETSCSF_WINDOW_SYNC_ACTIVE: {
    642:       MPI_Group   ingroup,outgroup;
    643:       PetscMPIInt isize,osize;

    645:       /* OpenMPI 4.0.2 with btl=wader does not like calling
    646:          - MPI_Win_complete when ogroup is empty
    647:          - MPI_Win_wait when igroup is empty
    648:          The MPI standard (Sec. 11.5.2 of MPI 3.1) only requires that
    649:          - each process who issues a call to MPI_Win_start issues a call to MPI_Win_Complete
    650:          - each process who issues a call to MPI_Win_post issues a call to MPI_Win_Wait
    651:       */
    652:       PetscSFGetGroups(sf,&ingroup,&outgroup);
    653:       MPI_Group_size(ingroup,&isize);
    654:       MPI_Group_size(outgroup,&osize);
    655:       if (osize) {MPI_Win_complete(*win);}
    656:       if (isize) {MPI_Win_wait(*win);}
    657:     } break;
    658:     default: SETERRQ(PetscObjectComm((PetscObject)sf),PETSC_ERR_PLIB,"Unknown synchronization type");
    659:     }
    660:   }
    661:   if (update) {
    662:     if (sync == PETSCSF_WINDOW_SYNC_LOCK) {
    663:       MPI_Win_fence(MPI_MODE_NOPUT|MPI_MODE_NOSUCCEED,*win);
    664:     }
    665:     PetscMemcpy(array,laddr,sf->nroots*bytes);
    666:   }
    667:   link->epoch = PETSC_FALSE;
    668:   link->inuse = PETSC_FALSE;
    669:   link->paddr = NULL;
    670:   if (!reuse) {
    671:     PetscFree(link->dyn_target_addr);
    672:     PetscFree(link->reqs);
    673:     MPI_Win_free(&link->win);
    674:     PetscFree(link);
    675:     *win = MPI_WIN_NULL;
    676:   }
    677:   return(0);
    678: }

    680: static PetscErrorCode PetscSFSetUp_Window(PetscSF sf)
    681: {
    682:   PetscSF_Window *w = (PetscSF_Window*)sf->data;
    684:   MPI_Group      ingroup,outgroup;

    687:   PetscSFSetUpRanks(sf,MPI_GROUP_EMPTY);
    688:   if (!w->dynsf) {
    689:     PetscInt    i;
    690:     PetscSFNode *remotes;

    692:     PetscMalloc1(sf->nranks,&remotes);
    693:     for (i=0;i<sf->nranks;i++) {
    694:       remotes[i].rank  = sf->ranks[i];
    695:       remotes[i].index = 0;
    696:     }
    697:     PetscSFDuplicate(sf,PETSCSF_DUPLICATE_RANKS,&w->dynsf);
    698:     PetscSFWindowSetFlavorType(w->dynsf,PETSCSF_WINDOW_FLAVOR_CREATE); /* break recursion */
    699:     PetscSFSetGraph(w->dynsf,1,sf->nranks,NULL,PETSC_OWN_POINTER,remotes,PETSC_OWN_POINTER);
    700:     PetscLogObjectParent((PetscObject)sf,(PetscObject)w->dynsf);
    701:   }
    702:   switch (w->sync) {
    703:   case PETSCSF_WINDOW_SYNC_ACTIVE:
    704:     PetscSFGetGroups(sf,&ingroup,&outgroup);
    705:   default:
    706:     break;
    707:   }
    708:   return(0);
    709: }

    711: static PetscErrorCode PetscSFSetFromOptions_Window(PetscOptionItems *PetscOptionsObject,PetscSF sf)
    712: {
    713:   PetscSF_Window          *w = (PetscSF_Window*)sf->data;
    714:   PetscErrorCode          ierr;
    715:   PetscSFWindowFlavorType flavor = w->flavor;

    718:   PetscOptionsHead(PetscOptionsObject,"PetscSF Window options");
    719:   PetscOptionsEnum("-sf_window_sync","synchronization type to use for PetscSF Window communication","PetscSFWindowSetSyncType",PetscSFWindowSyncTypes,(PetscEnum)w->sync,(PetscEnum*)&w->sync,NULL);
    720:   PetscOptionsEnum("-sf_window_flavor","flavor to use for PetscSF Window creation","PetscSFWindowSetFlavorType",PetscSFWindowFlavorTypes,(PetscEnum)flavor,(PetscEnum*)&flavor,NULL);
    721:   PetscSFWindowSetFlavorType(sf,flavor);
    722:   PetscOptionsTail();
    723:   return(0);
    724: }

    726: static PetscErrorCode PetscSFReset_Window(PetscSF sf)
    727: {
    728:   PetscSF_Window  *w = (PetscSF_Window*)sf->data;
    729:   PetscErrorCode  ierr;
    730:   PetscSFDataLink link,next;
    731:   PetscSFWinLink  wlink,wnext;
    732:   PetscInt        i;

    735:   for (link=w->link; link; link=next) {
    736:     next = link->next;
    737:     MPI_Type_free(&link->unit);
    738:     for (i=0; i<sf->nranks; i++) {
    739:       MPI_Type_free(&link->mine[i]);
    740:       MPI_Type_free(&link->remote[i]);
    741:     }
    742:     PetscFree2(link->mine,link->remote);
    743:     PetscFree(link);
    744:   }
    745:   w->link = NULL;
    746:   for (wlink=w->wins; wlink; wlink=wnext) {
    747:     wnext = wlink->next;
    748:     if (wlink->inuse) SETERRQ1(PetscObjectComm((PetscObject)sf),PETSC_ERR_ARG_WRONGSTATE,"Window still in use with address %p",(void*)wlink->addr);
    749:     PetscFree(wlink->dyn_target_addr);
    750:     PetscFree(wlink->reqs);
    751:     MPI_Win_free(&wlink->win);
    752:     PetscFree(wlink);
    753:   }
    754:   w->wins = NULL;
    755:   PetscSFDestroy(&w->dynsf);
    756:   if (w->info != MPI_INFO_NULL) {
    757:     MPI_Info_free(&w->info);
    758:   }
    759:   return(0);
    760: }

    762: static PetscErrorCode PetscSFDestroy_Window(PetscSF sf)
    763: {

    767:   PetscSFReset_Window(sf);
    768:   PetscFree(sf->data);
    769:   PetscObjectComposeFunction((PetscObject)sf,"PetscSFWindowSetSyncType_C",NULL);
    770:   PetscObjectComposeFunction((PetscObject)sf,"PetscSFWindowGetSyncType_C",NULL);
    771:   PetscObjectComposeFunction((PetscObject)sf,"PetscSFWindowSetFlavorType_C",NULL);
    772:   PetscObjectComposeFunction((PetscObject)sf,"PetscSFWindowGetFlavorType_C",NULL);
    773:   PetscObjectComposeFunction((PetscObject)sf,"PetscSFWindowSetInfo_C",NULL);
    774:   PetscObjectComposeFunction((PetscObject)sf,"PetscSFWindowGetInfo_C",NULL);
    775:   return(0);
    776: }

    778: static PetscErrorCode PetscSFView_Window(PetscSF sf,PetscViewer viewer)
    779: {
    780:   PetscSF_Window    *w = (PetscSF_Window*)sf->data;
    781:   PetscErrorCode    ierr;
    782:   PetscBool         iascii;
    783:   PetscViewerFormat format;

    786:   PetscViewerGetFormat(viewer,&format);
    787:   PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);
    788:   if (iascii) {
    789:     PetscViewerASCIIPrintf(viewer,"  current flavor=%s synchronization=%s MultiSF sort=%s\n",PetscSFWindowFlavorTypes[w->flavor],PetscSFWindowSyncTypes[w->sync],sf->rankorder ? "rank-order" : "unordered");
    790:     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
    791:       if (w->info != MPI_INFO_NULL) {
    792:         PetscMPIInt k,nkeys;
    793:         char        key[MPI_MAX_INFO_KEY], value[MPI_MAX_INFO_VAL];

    795:         MPI_Info_get_nkeys(w->info,&nkeys);
    796:         PetscViewerASCIIPrintf(viewer,"    current info with %d keys. Ordered key-value pairs follow:\n",nkeys);
    797:         for (k = 0; k < nkeys; k++) {
    798:           PetscMPIInt flag;

    800:           MPI_Info_get_nthkey(w->info,k,key);
    801:           MPI_Info_get(w->info,key,MPI_MAX_INFO_VAL,value,&flag);
    802:           if (!flag) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Missing key %s",key);
    803:           PetscViewerASCIIPrintf(viewer,"      %s = %s\n",key,value);
    804:         }
    805:       } else {
    806:         PetscViewerASCIIPrintf(viewer,"    current info=MPI_INFO_NULL\n");
    807:       }
    808:     }
    809:   }
    810:   return(0);
    811: }

    813: static PetscErrorCode PetscSFDuplicate_Window(PetscSF sf,PetscSFDuplicateOption opt,PetscSF newsf)
    814: {
    815:   PetscSF_Window        *w = (PetscSF_Window*)sf->data;
    816:   PetscErrorCode        ierr;
    817:   PetscSFWindowSyncType synctype;

    820:   synctype = w->sync;
    821:   /* HACK: Must use FENCE or LOCK when called from PetscSFGetGroups() because ACTIVE here would cause recursion. */
    822:   if (!sf->setupcalled) synctype = PETSCSF_WINDOW_SYNC_LOCK;
    823:   PetscSFWindowSetSyncType(newsf,synctype);
    824:   PetscSFWindowSetFlavorType(newsf,w->flavor);
    825:   PetscSFWindowSetInfo(newsf,w->info);
    826:   return(0);
    827: }

    829: static PetscErrorCode PetscSFBcastBegin_Window(PetscSF sf,MPI_Datatype unit,PetscMemType rootmtype,const void *rootdata,PetscMemType leafmtype,void *leafdata,MPI_Op op)
    830: {
    831:   PetscSF_Window     *w = (PetscSF_Window*)sf->data;
    832:   PetscErrorCode     ierr;
    833:   PetscInt           i,nranks;
    834:   const PetscMPIInt  *ranks;
    835:   const MPI_Aint     *target_disp;
    836:   const MPI_Datatype *mine,*remote;
    837:   MPI_Request        *reqs;
    838:   MPI_Win            win;

    841:   if (op != MPI_REPLACE) SETERRQ(PetscObjectComm((PetscObject)sf), PETSC_ERR_SUP, "PetscSFBcastBegin_Window with op!=MPI_REPLACE has not been implemented");
    842:   PetscSFGetRootRanks(sf,&nranks,&ranks,NULL,NULL,NULL);
    843:   PetscSFWindowGetDataTypes(sf,unit,&mine,&remote);
    844:   PetscSFGetWindow(sf,unit,(void*)rootdata,w->sync,PETSC_TRUE,MPI_MODE_NOPUT|MPI_MODE_NOPRECEDE,MPI_MODE_NOPUT,0,&target_disp,&reqs,&win);
    845:   for (i=0; i<nranks; i++) {
    846:     MPI_Aint tdp = target_disp ? target_disp[i] : 0;

    848:     if (w->sync == PETSCSF_WINDOW_SYNC_LOCK) {
    849:       MPI_Win_lock(MPI_LOCK_SHARED,ranks[i],MPI_MODE_NOCHECK,win);
    850: #if defined(PETSC_HAVE_MPI_RGET)
    851:       MPI_Rget(leafdata,1,mine[i],ranks[i],tdp,1,remote[i],win,&reqs[i]);
    852: #else
    853:       MPI_Get(leafdata,1,mine[i],ranks[i],tdp,1,remote[i],win);
    854: #endif
    855:     } else {
    856:       MPI_Get(leafdata,1,mine[i],ranks[i],tdp,1,remote[i],win);
    857:     }
    858:   }
    859:   return(0);
    860: }

    862: PetscErrorCode PetscSFBcastEnd_Window(PetscSF sf,MPI_Datatype unit,const void *rootdata,void *leafdata,MPI_Op op)
    863: {
    864:   PetscSF_Window *w = (PetscSF_Window*)sf->data;
    866:   MPI_Win        win;
    867:   MPI_Request    *reqs = NULL;

    870:   PetscSFFindWindow(sf,unit,rootdata,&win,&reqs);
    871:   if (reqs) {MPI_Waitall(sf->nranks,reqs,MPI_STATUSES_IGNORE);}
    872:   if (w->sync == PETSCSF_WINDOW_SYNC_LOCK) {
    873:     PetscInt           i,nranks;
    874:     const PetscMPIInt  *ranks;

    876:     PetscSFGetRootRanks(sf,&nranks,&ranks,NULL,NULL,NULL);
    877:     for (i=0; i<nranks; i++) {
    878:       MPI_Win_unlock(ranks[i],win);
    879:     }
    880:   }
    881:   PetscSFRestoreWindow(sf,unit,(void*)rootdata,w->sync,PETSC_TRUE,MPI_MODE_NOSTORE|MPI_MODE_NOSUCCEED,PETSC_FALSE,&win);
    882:   return(0);
    883: }

    885: PetscErrorCode PetscSFReduceBegin_Window(PetscSF sf,MPI_Datatype unit,PetscMemType leafmtype,const void *leafdata,PetscMemType rootmtype,void *rootdata,MPI_Op op)
    886: {
    887:   PetscSF_Window     *w = (PetscSF_Window*)sf->data;
    888:   PetscErrorCode     ierr;
    889:   PetscInt           i,nranks;
    890:   const PetscMPIInt  *ranks;
    891:   const MPI_Aint     *target_disp;
    892:   const MPI_Datatype *mine,*remote;
    893:   MPI_Win            win;

    896:   PetscSFGetRootRanks(sf,&nranks,&ranks,NULL,NULL,NULL);
    897:   PetscSFWindowGetDataTypes(sf,unit,&mine,&remote);
    898:   PetscSFWindowOpTranslate(&op);
    899:   PetscSFGetWindow(sf,unit,rootdata,w->sync,PETSC_TRUE,MPI_MODE_NOPRECEDE,0,0,&target_disp,NULL,&win);
    900:   for (i=0; i<nranks; i++) {
    901:     MPI_Aint tdp = target_disp ? target_disp[i] : 0;

    903:     if (w->sync == PETSCSF_WINDOW_SYNC_LOCK) {MPI_Win_lock(MPI_LOCK_SHARED,ranks[i],MPI_MODE_NOCHECK,win);}
    904:     MPI_Accumulate((void*)leafdata,1,mine[i],ranks[i],tdp,1,remote[i],op,win);
    905:     if (w->sync == PETSCSF_WINDOW_SYNC_LOCK) {MPI_Win_unlock(ranks[i],win);}
    906:   }
    907:   return(0);
    908: }

    910: static PetscErrorCode PetscSFReduceEnd_Window(PetscSF sf,MPI_Datatype unit,const void *leafdata,void *rootdata,MPI_Op op)
    911: {
    912:   PetscSF_Window *w = (PetscSF_Window*)sf->data;
    914:   MPI_Win        win;
    915:   MPI_Request    *reqs = NULL;

    918:   PetscSFFindWindow(sf,unit,rootdata,&win,&reqs);
    919:   if (reqs) {MPI_Waitall(sf->nranks,reqs,MPI_STATUSES_IGNORE);}
    920:   PetscSFRestoreWindow(sf,unit,rootdata,w->sync,PETSC_TRUE,MPI_MODE_NOSUCCEED,PETSC_TRUE,&win);
    921:   return(0);
    922: }

    924: static PetscErrorCode PetscSFFetchAndOpBegin_Window(PetscSF sf,MPI_Datatype unit,PetscMemType rootmtype,void *rootdata,PetscMemType leafmtype,const void *leafdata,void *leafupdate,MPI_Op op)
    925: {
    926:   PetscErrorCode     ierr;
    927:   PetscInt           i,nranks;
    928:   const PetscMPIInt  *ranks;
    929:   const MPI_Datatype *mine,*remote;
    930:   const MPI_Aint     *target_disp;
    931:   MPI_Win            win;
    932:   PetscSF_Window     *w = (PetscSF_Window*)sf->data;
    933: #if !defined(PETSC_HAVE_MPI_GET_ACCUMULATE)
    934:   PetscSFWindowFlavorType oldf;
    935: #endif

    938:   PetscSFGetRootRanks(sf,&nranks,&ranks,NULL,NULL,NULL);
    939:   PetscSFWindowGetDataTypes(sf,unit,&mine,&remote);
    940:   PetscSFWindowOpTranslate(&op);
    941: #if !defined(PETSC_HAVE_MPI_GET_ACCUMULATE)
    942:   /* FetchAndOp without MPI_Get_Accumulate requires locking.
    943:      we create a new window every time to not interfere with user-defined MPI_Info which may have used "no_locks"="true" */
    944:   oldf = w->flavor;
    945:   w->flavor = PETSCSF_WINDOW_FLAVOR_CREATE;
    946:   PetscSFGetWindow(sf,unit,rootdata,PETSCSF_WINDOW_SYNC_LOCK,PETSC_FALSE,0,0,0,&target_disp,NULL,&win);
    947: #else
    948:   PetscSFGetWindow(sf,unit,rootdata,w->sync,PETSC_TRUE,MPI_MODE_NOPRECEDE,0,0,&target_disp,NULL,&win);
    949: #endif
    950:   for (i=0; i<nranks; i++) {
    951:     MPI_Aint tdp = target_disp ? target_disp[i] : 0;

    953: #if !defined(PETSC_HAVE_MPI_GET_ACCUMULATE)
    954:     MPI_Win_lock(MPI_LOCK_EXCLUSIVE,ranks[i],0,win);
    955:     MPI_Get(leafupdate,1,mine[i],ranks[i],tdp,1,remote[i],win);
    956:     MPI_Accumulate((void*)leafdata,1,mine[i],ranks[i],tdp,1,remote[i],op,win);
    957:     MPI_Win_unlock(ranks[i],win);
    958: #else
    959:     if (w->sync == PETSCSF_WINDOW_SYNC_LOCK) {MPI_Win_lock(MPI_LOCK_SHARED,ranks[i],0,win);}
    960:     MPI_Get_accumulate((void*)leafdata,1,mine[i],leafupdate,1,mine[i],ranks[i],tdp,1,remote[i],op,win);
    961:     if (w->sync == PETSCSF_WINDOW_SYNC_LOCK) {MPI_Win_unlock(ranks[i],win);}
    962: #endif
    963:   }
    964: #if !defined(PETSC_HAVE_MPI_GET_ACCUMULATE)
    965:   w->flavor = oldf;
    966: #endif
    967:   return(0);
    968: }

    970: static PetscErrorCode PetscSFFetchAndOpEnd_Window(PetscSF sf,MPI_Datatype unit,void *rootdata,const void *leafdata,void *leafupdate,MPI_Op op)
    971: {
    973:   MPI_Win        win;
    974: #if defined(PETSC_HAVE_MPI_GET_ACCUMULATE)
    975:   PetscSF_Window *w = (PetscSF_Window*)sf->data;
    976: #endif
    977:   MPI_Request    *reqs = NULL;

    980:   PetscSFFindWindow(sf,unit,rootdata,&win,&reqs);
    981:   if (reqs) {MPI_Waitall(sf->nranks,reqs,MPI_STATUSES_IGNORE);}
    982: #if defined(PETSC_HAVE_MPI_GET_ACCUMULATE)
    983:   PetscSFRestoreWindow(sf,unit,rootdata,w->sync,PETSC_TRUE,MPI_MODE_NOSUCCEED,PETSC_TRUE,&win);
    984: #else
    985:   PetscSFRestoreWindow(sf,unit,rootdata,PETSCSF_WINDOW_SYNC_LOCK,PETSC_FALSE,0,PETSC_TRUE,&win);
    986: #endif
    987:   return(0);
    988: }

    990: PETSC_INTERN PetscErrorCode PetscSFCreate_Window(PetscSF sf)
    991: {
    992:   PetscSF_Window *w = (PetscSF_Window*)sf->data;

    996:   sf->ops->SetUp           = PetscSFSetUp_Window;
    997:   sf->ops->SetFromOptions  = PetscSFSetFromOptions_Window;
    998:   sf->ops->Reset           = PetscSFReset_Window;
    999:   sf->ops->Destroy         = PetscSFDestroy_Window;
    1000:   sf->ops->View            = PetscSFView_Window;
    1001:   sf->ops->Duplicate       = PetscSFDuplicate_Window;
    1002:   sf->ops->BcastBegin      = PetscSFBcastBegin_Window;
    1003:   sf->ops->BcastEnd        = PetscSFBcastEnd_Window;
    1004:   sf->ops->ReduceBegin     = PetscSFReduceBegin_Window;
    1005:   sf->ops->ReduceEnd       = PetscSFReduceEnd_Window;
    1006:   sf->ops->FetchAndOpBegin = PetscSFFetchAndOpBegin_Window;
    1007:   sf->ops->FetchAndOpEnd   = PetscSFFetchAndOpEnd_Window;

    1009:   PetscNewLog(sf,&w);
    1010:   sf->data  = (void*)w;
    1011:   w->sync   = PETSCSF_WINDOW_SYNC_FENCE;
    1012:   w->flavor = PETSCSF_WINDOW_FLAVOR_CREATE;
    1013:   w->info   = MPI_INFO_NULL;

    1015:   PetscObjectComposeFunction((PetscObject)sf,"PetscSFWindowSetSyncType_C",PetscSFWindowSetSyncType_Window);
    1016:   PetscObjectComposeFunction((PetscObject)sf,"PetscSFWindowGetSyncType_C",PetscSFWindowGetSyncType_Window);
    1017:   PetscObjectComposeFunction((PetscObject)sf,"PetscSFWindowSetFlavorType_C",PetscSFWindowSetFlavorType_Window);
    1018:   PetscObjectComposeFunction((PetscObject)sf,"PetscSFWindowGetFlavorType_C",PetscSFWindowGetFlavorType_Window);
    1019:   PetscObjectComposeFunction((PetscObject)sf,"PetscSFWindowSetInfo_C",PetscSFWindowSetInfo_Window);
    1020:   PetscObjectComposeFunction((PetscObject)sf,"PetscSFWindowGetInfo_C",PetscSFWindowGetInfo_Window);

    1022: #if defined(OMPI_MAJOR_VERSION) && (OMPI_MAJOR_VERSION < 1 || (OMPI_MAJOR_VERSION == 1 && OMPI_MINOR_VERSION <= 6))
    1023:   {
    1024:     PetscBool ackbug = PETSC_FALSE;
    1025:     PetscOptionsGetBool(NULL,NULL,"-acknowledge_ompi_onesided_bug",&ackbug,NULL);
    1026:     if (ackbug) {
    1027:       PetscInfo(sf,"Acknowledged Open MPI bug, proceeding anyway. Expect memory corruption.\n");
    1028:     } else SETERRQ(PetscObjectComm((PetscObject)sf),PETSC_ERR_LIB,"Open MPI is known to be buggy (https://svn.open-mpi.org/trac/ompi/ticket/1905 and 2656), use -acknowledge_ompi_onesided_bug to proceed");
    1029:   }
    1030: #endif
    1031:   return(0);
    1032: }