ExchangeOldWindowFlat Subroutine

  1. SELF_SolutionMigration.f90
  2. SELF_SolutionMigration
  3. ExchangeOldWindowFlat

public subroutine ExchangeOldWindowFlat(decomp, perElem, nvar, nLocalOld, uLocal, winFirst, winLast, wFirst, wLast, uWin, nBytesRecv, nBytesSent, nElemRemote)

The complete host-memory migration: post the messages, copy the part of the window this rank already owns while they are in flight, then wait. This is the portable backend's whole implementation; the GPU backend calls PostOldWindowExchange / FinishOldWindowExchange itself so that it can serve the local part with a device-to-device copy instead.

Arguments

TypeIntentOptionalAttributesName
type(DomainDecomposition), intent(in) :: decomp
integer, intent(in) :: perElem
integer, intent(in) :: nvar
integer, intent(in) :: nLocalOld
real(kind=prec), intent(in) :: uLocal(*)
integer, intent(in) :: winFirst(1:decomp%nRanks)
integer, intent(in) :: winLast(1:decomp%nRanks)
integer, intent(in) :: wFirst
integer, intent(in) :: wLast
real(kind=prec), intent(inout) :: uWin(*)
integer(kind=int64), intent(inout) :: nBytesRecv
integer(kind=int64), intent(inout) :: nBytesSent
integer(kind=int64), intent(inout) :: nElemRemote

Calls

proc~~exchangeoldwindowflat~~CallsGraph proc~exchangeoldwindowflat ExchangeOldWindowFlat proc~postoldwindowexchange PostOldWindowExchange proc~exchangeoldwindowflat->proc~postoldwindowexchange proc~ownedrun OwnedRun proc~exchangeoldwindowflat->proc~ownedrun proc~finisholdwindowexchange FinishOldWindowExchange proc~exchangeoldwindowflat->proc~finisholdwindowexchange proc~postoldwindowexchange->proc~ownedrun mpi_isend mpi_isend proc~postoldwindowexchange->mpi_isend mpi_irecv mpi_irecv proc~postoldwindowexchange->mpi_irecv mpi_waitall mpi_waitall proc~finisholdwindowexchange->mpi_waitall

Called by

proc~~exchangeoldwindowflat~~CalledByGraph proc~exchangeoldwindowflat ExchangeOldWindowFlat proc~migrateoldwindow_dgmodel2d_t MigrateOldWindow_DGModel2D_t proc~migrateoldwindow_dgmodel2d_t->proc~exchangeoldwindowflat proc~migrateoldwindow_dgmodel3d_t MigrateOldWindow_DGModel3D_t proc~migrateoldwindow_dgmodel3d_t->proc~exchangeoldwindowflat proc~exchangeoldwindow ExchangeOldWindow proc~exchangeoldwindow->proc~exchangeoldwindowflat proc~exchangeoldwindow~2 ExchangeOldWindow proc~exchangeoldwindow~2->proc~exchangeoldwindowflat proc~adapt_amrcontroller2d Adapt_AMRController2D proc~adapt_amrcontroller2d->proc~migrateoldwindow_dgmodel2d_t proc~adapt_amrcontroller3d Adapt_AMRController3D proc~adapt_amrcontroller3d->proc~migrateoldwindow_dgmodel3d_t

Contents

Source Code

ExchangeOldWindowFlat

Source Code

  subroutine ExchangeOldWindowFlat(decomp,perElem,nvar,nLocalOld,uLocal,winFirst,winLast, &
                                   wFirst,wLast,uWin,nBytesRecv,nBytesSent,nElemRemote)
    !! The complete host-memory migration: post the messages, copy the part of the window this
    !! rank already owns while they are in flight, then wait. This is the portable backend's whole
    !! implementation; the GPU backend calls PostOldWindowExchange / FinishOldWindowExchange
    !! itself so that it can serve the local part with a device-to-device copy instead.
    implicit none
    type(DomainDecomposition),intent(in) :: decomp
    integer,intent(in) :: perElem
    integer,intent(in) :: nvar
    integer,intent(in) :: nLocalOld
    real(prec),intent(in) :: uLocal(*)
    integer,intent(in) :: winFirst(1:decomp%nRanks)
    integer,intent(in) :: winLast(1:decomp%nRanks)
    integer,intent(in) :: wFirst
    integer,intent(in) :: wLast
    real(prec),intent(inout) :: uWin(*)
    integer(int64),intent(inout) :: nBytesRecv
    integer(int64),intent(inout) :: nBytesSent
    integer(int64),intent(inout) :: nElemRemote
    ! Local
    integer :: a,b,e,iv,p,msgCount
    integer :: myFirst,nWinElem
    integer(int64) :: dst,src !! int64 for the reason given in PostOldWindowExchange
    integer,allocatable :: requests(:)

    myFirst = decomp%offsetElem(decomp%rankId+1)+1
    nWinElem = max(wLast-wFirst+1,0)

    allocate(requests(1:2*nvar*decomp%nRanks))
    msgCount = 0
    call PostOldWindowExchange(decomp,perElem,nvar,nLocalOld,uLocal,winFirst,winLast, &
                               wFirst,wLast,uWin,requests,msgCount, &
                               nBytesRecv,nBytesSent,nElemRemote)

    ! The part of my window I already own, copied while the messages are in flight. Element order
    ! within a variable is the storage order of both buffers, so this is a pure byte move and the
    ! migrated window is bit-identical to the v1 allgathered field.
    call OwnedRun(decomp%offsetElem,decomp%rankId+1,wFirst,wLast,a,b)
    do iv = 1,nvar
      do e = a,b
        dst = int(perElem,int64)*(int(e-wFirst,int64)+int(nWinElem,int64)*(iv-1))
        src = int(perElem,int64)*(int(e-myFirst,int64)+int(nLocalOld,int64)*(iv-1))
        do p = 1,perElem
          uWin(dst+p) = uLocal(src+p)
        enddo
      enddo
    enddo

    call FinishOldWindowExchange(requests,msgCount)
    deallocate(requests)

  endsubroutine ExchangeOldWindowFlat