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|
!
! Copyright (C) 2002-2008 Quantum ESPRESSO group
! This file is distributed under the terms of the
! GNU General Public License. See the file `License'
! in the root directory of the present distribution,
! or http://www.gnu.org/copyleft/gpl.txt .
!
!
MODULE mp_wave
IMPLICIT NONE
SAVE
CONTAINS
SUBROUTINE mergewf ( pw, pwt, ngwl, ig_l2g, mpime, nproc, root, comm )
! ... This subroutine merges the pieces of a wave functions (pw) splitted across
! ... processors into a total wave function (pwt) containing al the components
! ... in a pre-defined order (the same as if only one processor is used)
USE kinds
USE parallel_include
IMPLICIT NONE
COMPLEX(DP), intent(in) :: PW(:)
COMPLEX(DP), intent(out) :: PWT(:)
INTEGER, INTENT(IN) :: mpime ! index of the calling processor ( starting from 0 )
INTEGER, INTENT(IN) :: nproc ! number of processors
INTEGER, INTENT(IN) :: root ! root processor ( the one that should receive the data )
INTEGER, INTENT(IN) :: comm ! communicator
INTEGER, INTENT(IN) :: ig_l2g(:)
INTEGER, INTENT(IN) :: ngwl
INTEGER, ALLOCATABLE :: ig_ip(:)
COMPLEX(DP), ALLOCATABLE :: pw_ip(:)
INTEGER :: ierr, i, ip, ngw_ip, ngw_lmax, itmp, igwx, gid
#if defined __MPI
INTEGER :: istatus(MPI_STATUS_SIZE)
#endif
!
! ... Subroutine Body
!
igwx = MAXVAL( ig_l2g(1:ngwl) )
#if defined __MPI
gid = comm
! ... Get local and global wavefunction dimensions
CALL MPI_ALLREDUCE( ngwl, ngw_lmax, 1, MPI_INTEGER, MPI_MAX, gid, IERR )
CALL MPI_ALLREDUCE( igwx, itmp, 1, MPI_INTEGER, MPI_MAX, gid, IERR )
igwx = itmp
#endif
IF( igwx > SIZE( pwt ) ) &
CALL errore(' mergewf ',' wrong size for pwt ',SIZE(pwt) )
#if defined __MPI
DO ip = 1, nproc
IF( (ip-1) /= root ) THEN
! ... In turn each processors send to root the wave components and their indexes in the
! ... global array
IF ( mpime == (ip-1) ) THEN
CALL MPI_SEND( ig_l2g, ngwl, MPI_INTEGER, ROOT, IP, gid, IERR )
CALL MPI_SEND( pw(1), ngwl, MPI_DOUBLE_COMPLEX, ROOT, IP+NPROC, gid, IERR )
END IF
IF ( mpime == root) THEN
ALLOCATE(ig_ip(ngw_lmax))
ALLOCATE(pw_ip(ngw_lmax))
CALL MPI_RECV( ig_ip, ngw_lmax, MPI_INTEGER, (ip-1), IP, gid, istatus, IERR )
CALL MPI_RECV( pw_ip, ngw_lmax, MPI_DOUBLE_COMPLEX, (ip-1), IP+NPROC, gid, istatus, IERR )
CALL MPI_GET_COUNT( istatus, MPI_DOUBLE_COMPLEX, ngw_ip, ierr )
DO I = 1, ngw_ip
PWT(ig_ip(i)) = pw_ip(i)
END DO
DEALLOCATE(ig_ip)
DEALLOCATE(pw_ip)
END IF
ELSE
IF(mpime == root) THEN
DO I = 1, ngwl
PWT(ig_l2g(i)) = pw(i)
END DO
END IF
END IF
CALL MPI_BARRIER( gid, IERR )
END DO
#elif ! defined __MPI
DO I = 1, ngwl
! WRITE( stdout,*) 'MW ', ig_l2g(i), i
PWT( ig_l2g(i) ) = pw(i)
END DO
#else
CALL errore(' MERGEWF ',' no communication protocol ',0)
#endif
RETURN
END SUBROUTINE mergewf
!=----------------------------------------------------------------------------=!
SUBROUTINE splitwf ( pw, pwt, ngwl, ig_l2g, mpime, nproc, root, comm )
! ... This subroutine splits a total wave function (pwt) containing al the components
! ... in a pre-defined order (the same as if only one processor is used), across
! ... processors (pw).
USE kinds
USE parallel_include
IMPLICIT NONE
COMPLEX(DP), INTENT(OUT) :: PW(:)
COMPLEX(DP), INTENT(IN) :: PWT(:)
INTEGER, INTENT(IN) :: mpime, nproc, root
INTEGER, INTENT(IN) :: comm ! communicator
INTEGER, INTENT(IN) :: ig_l2g(:)
INTEGER, INTENT(IN) :: ngwl
INTEGER, ALLOCATABLE :: ig_ip(:)
COMPLEX(DP), ALLOCATABLE :: pw_ip(:)
INTEGER ierr, i, ngw_ip, ip, ngw_lmax, gid, igwx, itmp
#if defined __MPI
integer istatus(MPI_STATUS_SIZE)
#endif
!
! ... Subroutine Body
!
igwx = MAXVAL( ig_l2g(1:ngwl) )
#if defined __MPI
gid = comm
! ... Get local and global wavefunction dimensions
CALL MPI_ALLREDUCE(ngwl, ngw_lmax, 1, MPI_INTEGER, MPI_MAX, gid, IERR )
CALL MPI_ALLREDUCE(igwx, itmp , 1, MPI_INTEGER, MPI_MAX, gid, IERR )
igwx = itmp
#endif
IF( igwx > SIZE( pwt ) ) &
CALL errore(' splitwf ',' wrong size for pwt ',SIZE(pwt) )
#if defined __MPI
DO ip = 1, nproc
! ... In turn each processor send to root the the indexes of its wavefunction conponents
! ... Root receive the indexes and send the componens of the wavefunction read from the disk (pwt)
IF ( (ip-1) /= root ) THEN
IF ( mpime == (ip-1) ) THEN
CALL MPI_SEND( ig_l2g, ngwl, MPI_INTEGER, ROOT, IP, gid,IERR)
CALL MPI_RECV( pw(1), ngwl, MPI_DOUBLE_COMPLEX, ROOT, IP+NPROC, gid, istatus, IERR )
END IF
IF ( mpime == root ) THEN
ALLOCATE(ig_ip(ngw_lmax))
ALLOCATE(pw_ip(ngw_lmax))
CALL MPI_RECV( ig_ip, ngw_lmax, MPI_INTEGER, (ip-1), IP, gid, istatus, IERR )
CALL MPI_GET_COUNT(istatus, MPI_INTEGER, ngw_ip, ierr)
DO i = 1, ngw_ip
pw_ip(i) = PWT(ig_ip(i))
END DO
CALL MPI_SEND( pw_ip, ngw_ip, MPI_DOUBLE_COMPLEX, (ip-1), IP+NPROC, gid, IERR )
DEALLOCATE(ig_ip)
DEALLOCATE(pw_ip)
END IF
ELSE
IF ( mpime == root ) THEN
DO i = 1, ngwl
pw(i) = PWT(ig_l2g(i))
END DO
END IF
END IF
CALL MPI_BARRIER(gid, IERR)
END DO
#elif ! defined __MPI
DO I = 1, ngwl
pw(i) = pwt( ig_l2g(i) )
END DO
#else
CALL errore(' SPLITWF ',' no communication protocol ',0)
#endif
RETURN
END SUBROUTINE splitwf
SUBROUTINE mergeig(igl, igtot, ngl, mpime, nproc, root, comm)
! ... This subroutine merges the pieces of a vector splitted across
! ... processors into a total vector (igtot) containing al the components
! ... in a pre-defined order (the same as if only one processor is used)
USE kinds
USE parallel_include
IMPLICIT NONE
INTEGER, intent(in) :: igl(:)
INTEGER, intent(out) :: igtot(:)
INTEGER, INTENT(IN) :: mpime ! index of the calling processor ( starting from 0 )
INTEGER, INTENT(IN) :: nproc ! number of processors
INTEGER, INTENT(IN) :: root ! root processor ( the one that should receive the data )
INTEGER, INTENT(IN) :: comm ! communicator
INTEGER, INTENT(IN) :: ngl
INTEGER, ALLOCATABLE :: ig_ip(:)
INTEGER :: ierr, i, ip, ng_ip, ng_lmax, ng_g, gid, igs
#if defined __MPI
INTEGER :: istatus(MPI_STATUS_SIZE)
#endif
#if defined __MPI
gid = comm
! ... Get local and global wavefunction dimensions
CALL MPI_ALLREDUCE( ngl, ng_lmax, 1, MPI_INTEGER, MPI_MAX, gid, IERR )
CALL MPI_ALLREDUCE( ngl, ng_g , 1, MPI_INTEGER, MPI_SUM, gid, IERR )
IF( ng_g > SIZE( igtot ) ) THEN
CALL errore(' mergeig ',' wrong size for igtot ',SIZE(igtot) )
END IF
igs = 1
DO ip = 1, nproc
IF( (ip-1) /= root ) THEN
! ... In turn each processors send to root the wave components and their indexes in the
! ... global array
IF ( mpime == (ip-1) ) THEN
CALL MPI_SEND( igl(1), ngl, MPI_INTEGER, ROOT, IP, gid, IERR )
END IF
IF ( mpime == root) THEN
ALLOCATE( ig_ip(ng_lmax) )
CALL MPI_RECV( ig_ip, ng_lmax, MPI_INTEGER, (ip-1), IP, gid, istatus, IERR )
CALL MPI_GET_COUNT( istatus, MPI_INTEGER, ng_ip, ierr )
DO i = 1, ng_ip
igtot( igs + i - 1 ) = ig_ip( i )
END DO
DEALLOCATE(ig_ip)
END IF
ELSE
IF(mpime == root) THEN
ng_ip = ngl
DO i = 1, ngl
igtot( igs + i - 1 ) = igl( i )
END DO
END IF
END IF
IF(mpime == root) THEN
igs = igs + ng_ip
END IF
CALL MPI_BARRIER( gid, IERR )
END DO
#elif ! defined __MPI
igtot( 1:ngl ) = igl( 1:ngl )
#else
CALL errore(' mergeig ',' no communication protocol ',0)
#endif
RETURN
END SUBROUTINE mergeig
!=----------------------------------------------------------------------------=!
SUBROUTINE splitig(igl, igtot, ngl, mpime, nproc, root, comm)
! ... This subroutine splits a replicated vector (igtot) stored on the root proc
! ... across processors (igl).
USE kinds
USE parallel_include
IMPLICIT NONE
INTEGER, INTENT(OUT) :: igl(:)
INTEGER, INTENT(IN) :: igtot(:)
INTEGER, INTENT(IN) :: mpime, nproc, root
INTEGER, INTENT(IN) :: comm ! communicator
INTEGER, INTENT(IN) :: ngl
INTEGER ierr, i, ng_ip, ip, ng_lmax, ng_g, gid, igs
#if defined __MPI
integer istatus(MPI_STATUS_SIZE)
#endif
INTEGER, ALLOCATABLE :: ig_ip(:)
#if defined __MPI
gid = comm
! ... Get local and global wavefunction dimensions
CALL MPI_ALLREDUCE(ngl, ng_lmax, 1, MPI_INTEGER, MPI_MAX, gid, IERR )
CALL MPI_ALLREDUCE(ngl, ng_g , 1, MPI_INTEGER, MPI_SUM, gid, IERR )
IF( ng_g > SIZE( igtot ) ) THEN
CALL errore(' splitig ',' wrong size for igtot ', SIZE(igtot) )
END IF
igs = 1
DO ip = 1, nproc
! ... In turn each processor sends to root the indices of its wavefunction components
! ... Root receives the indices and sends the components of the wavefunction read from the disk (pwt)
IF ( (ip-1) /= root ) THEN
IF ( mpime == (ip-1) ) THEN
CALL MPI_SEND( ngl, 1 , MPI_INTEGER, ROOT, IP, gid,IERR)
CALL MPI_RECV( igl, ngl, MPI_INTEGER, ROOT, IP+NPROC, gid, istatus, IERR )
END IF
IF ( mpime == root ) THEN
ALLOCATE(ig_ip(ng_lmax))
CALL MPI_RECV( ng_ip, 1, MPI_INTEGER, (ip-1), IP, gid, istatus, IERR )
DO i = 1, ng_ip
ig_ip(i) = igtot( igs + i - 1)
END DO
CALL MPI_SEND( ig_ip, ng_ip, MPI_INTEGER, (ip-1), IP+NPROC, gid, IERR )
DEALLOCATE(ig_ip)
END IF
ELSE
IF ( mpime == root ) THEN
ng_ip = ngl
DO i = 1, ng_ip
igl(i) = igtot( igs + i - 1)
END DO
END IF
END IF
IF( mpime == root ) igs = igs + ng_ip
CALL MPI_BARRIER(gid, IERR)
END DO
#elif ! defined __MPI
igl( 1:ngl ) = igtot( 1:ngl )
#else
CALL errore(' splitig ',' no communication protocol ',0)
#endif
RETURN
END SUBROUTINE splitig
!=----------------------------------------------------------------------------=!
SUBROUTINE pwscatter( c, ctmp, ngw, indi_l, sour_indi, dest_indi, &
n_indi_rcv, n_indi_snd, icntix, mpime, nproc, group )
USE kinds
USE parallel_include
implicit none
integer :: indi_l(:) ! list of G-vec index to be exchanged
integer :: sour_indi(:) ! the list of source processors
integer :: dest_indi(:) ! the list of destination processors
integer :: n_indi_rcv ! number of G-vectors to be received
integer :: n_indi_snd ! number of G-vectors to be sent
integer :: icntix ! total number of G-vec to be exchanged
INTEGER, INTENT(IN) :: nproc, mpime, group
COMPLEX(DP) :: c(:)
COMPLEX(DP) :: ctmp(:)
integer :: ngw
integer :: ig, icsize
INTEGER :: me, idest, isour, ierr
COMPLEX(DP), ALLOCATABLE :: my_buffer( : )
COMPLEX(DP), ALLOCATABLE :: mp_snd_buffer( : )
COMPLEX(DP), ALLOCATABLE :: mp_rcv_buffer( : )
INTEGER, ALLOCATABLE :: ibuf(:)
!
! ... SUBROUTINE BODY
!
me = mpime + 1
if( icntix .lt. 1 ) then
icsize = 1
else
icsize = icntix
endif
ALLOCATE( mp_snd_buffer( icsize * nproc ) )
ALLOCATE( mp_rcv_buffer( icsize * nproc ) )
ALLOCATE( my_buffer( ngw ) )
ALLOCATE( ibuf( nproc ) )
ctmp = ( 0.0_DP, 0.0_DP )
! WRITE( stdout,*) 'D: ', nproc, mpime, group
ibuf = 0
DO IG = 1, n_indi_snd
idest = dest_indi(ig)
ibuf(idest) = ibuf(idest) + 1;
if(idest .ne. me) then
mp_snd_buffer( ibuf(idest) + (idest-1)*icsize ) = C( indi_l( ig ) )
else
my_buffer(ibuf(idest)) = C(indi_l(ig))
end if
end do
#if defined __MPI
call MPI_ALLTOALL( mp_snd_buffer(1), icsize, MPI_DOUBLE_COMPLEX, &
mp_rcv_buffer(1), icsize, MPI_DOUBLE_COMPLEX, &
group, ierr)
#else
CALL errore(' pwscatter ',' no communication protocol ',0)
#endif
ibuf = 0
DO IG = 1, n_indi_rcv
isour = sour_indi(ig)
if(isour.gt.0 .and. isour.ne.me) then
ibuf(isour) = ibuf(isour) + 1
CTMP(ig) = mp_rcv_buffer(ibuf(isour) + (isour-1)*icsize)
else if(isour.gt.0) then
ibuf(isour) = ibuf(isour) + 1
CTMP(ig) = my_buffer(ibuf(isour))
else
CTMP(ig) = (0.0_DP,0.0_DP)
end if
end do
DEALLOCATE( mp_snd_buffer )
DEALLOCATE( mp_rcv_buffer )
DEALLOCATE( my_buffer )
DEALLOCATE( ibuf )
RETURN
END SUBROUTINE pwscatter
!=----------------------------------------------------------------------------=!
SUBROUTINE redistwf( c_dist_pw, c_dist_st, npw_p, nst_p, comm, idir )
!
! Redistribute wave function.
! c_dist_pw are the wave functions with plane waves distributed over processors
! c_dist_st are the wave functions with electronic states distributed over processors
!
USE kinds
USE parallel_include
implicit none
COMPLEX(DP) :: c_dist_pw(:,:)
COMPLEX(DP) :: c_dist_st(:,:)
INTEGER, INTENT(IN) :: npw_p(:) ! the number of plane wave on each processor
INTEGER, INTENT(IN) :: nst_p(:) ! the number of states on each processor
INTEGER, INTENT(IN) :: comm ! group communicator
INTEGER, INTENT(IN) :: idir ! direction of the redistribution
! idir > 0 c_dist_pw --> c_dist_st
! idir < 0 c_dist_pw <-- c_dist_st
INTEGER :: mpime, nproc, ierr, npw_t, nst_t, proc, i, j, ngpww, ii
INTEGER, ALLOCATABLE :: rdispls(:), recvcount(:)
INTEGER, ALLOCATABLE :: sendcount(:), sdispls(:)
COMPLEX(DP), ALLOCATABLE :: ctmp( : )
#ifdef __MPI
CALL mpi_comm_rank( comm, mpime, ierr )
IF( ierr /= 0 ) CALL errore( ' wf_redist ', ' mpi_comm_rank ', ierr )
CALL mpi_comm_size( comm, nproc, ierr )
IF( ierr /= 0 ) CALL errore( ' wf_redist ', ' mpi_comm_size ', ierr )
ALLOCATE( rdispls( nproc ), recvcount( nproc ), sendcount( nproc ), sdispls( nproc ) )
npw_t = 0
nst_t = 0
DO proc=1,nproc
sendcount(proc) = npw_p(mpime+1) * nst_p(proc)
recvcount(proc) = npw_p(proc) * nst_p(mpime+1)
npw_t = npw_t + npw_p(proc)
nst_t = nst_t + nst_p(proc)
END DO
sdispls(1)=0
rdispls(1)=0
DO proc=2,nproc
sdispls(proc) = sdispls(proc-1) + sendcount(proc-1)
rdispls(proc) = rdispls(proc-1) + recvcount(proc-1)
END DO
ALLOCATE( ctmp( npw_t * nst_p( mpime + 1 ) ) )
IF( idir > 0 ) THEN
!
! ... Step 1. Communicate to all Procs so that each proc has all
! ... G-vectors and some states instead of all states and some
! ... G-vectors. This information is stored in the 1-d array ctmp.
!
CALL MPI_BARRIER( comm, ierr )
IF( ierr /= 0 ) CALL errore( ' wf_redist ', ' mpi_barrier ', ierr )
!
CALL MPI_ALLTOALLV( c_dist_pw, sendcount, sdispls, MPI_DOUBLE_COMPLEX, &
& ctmp, recvcount, rdispls, MPI_DOUBLE_COMPLEX, comm, ierr)
IF( ierr /= 0 ) CALL errore( ' wf_redist ', ' mpi_alltoallv ', ierr )
!
! Step 2. Convert the 1-d array ctmp into a 2-d array consistent with the
! original notation c(ngw,nbsp). Psitot contains ntot = SUM_Procs(ngw) G-vecs
! and nstat states instead of all nbsp states
!
ngpww = 0
DO proc = 1, nproc
DO i = 1, nst_p(mpime+1)
ii = (i-1) * npw_p(proc)
DO j = 1, npw_p(proc)
c_dist_st( j + ngpww, i ) = ctmp( rdispls(proc) + j + ii )
END DO
END DO
ngpww = ngpww + npw_p(proc)
END DO
ELSE
!
! Step 4. Convert the 2-d array c_dist_st into 1-d array
!
ngpww = 0
DO proc = 1, nproc
DO i = 1, nst_p(mpime+1)
ii = (i-1) * npw_p(proc)
DO j = 1, npw_p(proc)
ctmp( rdispls(proc) + j + ii ) = c_dist_st( j + ngpww, i )
END DO
END DO
ngpww = ngpww + npw_p(proc)
END DO
!
! Step 5. Redistribute among processors. The result is stored in 2-d
! array c_dist_pw consistent with the notation c(ngw,nbsp)
!
CALL MPI_BARRIER( comm, ierr )
IF( ierr /= 0 ) CALL errore( ' wf_redist ', ' mpi_barrier ', ierr )
CALL MPI_ALLTOALLV( ctmp, recvcount, rdispls, MPI_DOUBLE_COMPLEX, &
& c_dist_pw, sendcount , sdispls, MPI_DOUBLE_COMPLEX, comm, ierr )
IF( ierr /= 0 ) CALL errore( ' wf_redist ', ' mpi_alltoallv ', ierr )
END IF
DEALLOCATE( ctmp )
DEALLOCATE( rdispls, recvcount, sendcount, sdispls )
#endif
RETURN
END SUBROUTINE redistwf
!=----------------------------------------------------------------------------=!
SUBROUTINE redistwfr( c_dist_pw, c_dist_st, npw_p, nst_p, comm, idir )
!
! Redistribute wave function.
! c_dist_pw are the wave functions with plane waves distributed over processors
! c_dist_st are the wave functions with electronic states distributed over processors
!
USE kinds
USE parallel_include
implicit none
REAL(DP) :: c_dist_pw(:,:)
REAL(DP) :: c_dist_st(:,:)
INTEGER, INTENT(IN) :: npw_p(:) ! the number of plane wave on each processor
INTEGER, INTENT(IN) :: nst_p(:) ! the number of states on each processor
INTEGER, INTENT(IN) :: comm ! group communicator
INTEGER, INTENT(IN) :: idir ! direction of the redistribution
! idir > 0 c_dist_pw --> c_dist_st
! idir < 0 c_dist_pw <-- c_dist_st
INTEGER :: mpime, nproc, ierr, npw_t, nst_t, proc, i, j, ngpww
INTEGER, ALLOCATABLE :: rdispls(:), recvcount(:)
INTEGER, ALLOCATABLE :: sendcount(:), sdispls(:)
REAL(DP), ALLOCATABLE :: ctmp( : )
#ifdef __MPI
CALL mpi_comm_rank( comm, mpime, ierr )
IF( ierr /= 0 ) CALL errore( ' wf_redist ', ' mpi_comm_rank ', ierr )
CALL mpi_comm_size( comm, nproc, ierr )
IF( ierr /= 0 ) CALL errore( ' wf_redist ', ' mpi_comm_size ', ierr )
ALLOCATE( rdispls( nproc ), recvcount( nproc ), sendcount( nproc ), sdispls( nproc ) )
npw_t = 0
nst_t = 0
DO proc=1,nproc
sendcount(proc) = npw_p(mpime+1) * nst_p(proc)
recvcount(proc) = npw_p(proc) * nst_p(mpime+1)
npw_t = npw_t + npw_p(proc)
nst_t = nst_t + nst_p(proc)
END DO
sdispls(1)=0
rdispls(1)=0
DO proc=2,nproc
sdispls(proc) = sdispls(proc-1) + sendcount(proc-1)
rdispls(proc) = rdispls(proc-1) + recvcount(proc-1)
END DO
ALLOCATE( ctmp( npw_t * nst_p( mpime + 1 ) ) )
IF( idir > 0 ) THEN
!
! ... Step 1. Communicate to all Procs so that each proc has all
! ... G-vectors and some states instead of all states and some
! ... G-vectors. This information is stored in the 1-d array ctmp.
!
CALL MPI_BARRIER( comm, ierr )
IF( ierr /= 0 ) CALL errore( ' wf_redist ', ' mpi_barrier ', ierr )
!
CALL MPI_ALLTOALLV( c_dist_pw, sendcount, sdispls, MPI_DOUBLE_PRECISION, &
& ctmp, recvcount, rdispls, MPI_DOUBLE_PRECISION, comm, ierr)
IF( ierr /= 0 ) CALL errore( ' wf_redist ', ' mpi_alltoallv ', ierr )
!
! Step 2. Convert the 1-d array ctmp into a 2-d array consistent with the
! original notation c(ngw,nbsp). Psitot contains ntot = SUM_Procs(ngw) G-vecs
! and nstat states instead of all nbsp states
!
ngpww = 0
DO proc = 1, nproc
DO i = 1, nst_p(mpime+1)
DO j = 1, npw_p(proc)
c_dist_st( j + ngpww, i ) = ctmp( rdispls(proc) + j + (i-1) * npw_p(proc) )
END DO
END DO
ngpww = ngpww + npw_p(proc)
END DO
ELSE
!
! Step 4. Convert the 2-d array c_dist_st into 1-d array
!
ngpww = 0
DO proc = 1, nproc
DO i = 1, nst_p(mpime+1)
DO j = 1, npw_p(proc)
ctmp( rdispls(proc) + j + (i-1) * npw_p(proc) ) = c_dist_st( j + ngpww, i )
END DO
END DO
ngpww = ngpww + npw_p(proc)
END DO
!
! Step 5. Redistribute among processors. The result is stored in 2-d
! array c_dist_pw consistent with the notation c(ngw,nbsp)
!
CALL MPI_BARRIER( comm, ierr )
IF( ierr /= 0 ) CALL errore( ' wf_redist ', ' mpi_barrier ', ierr )
CALL MPI_ALLTOALLV( ctmp, recvcount, rdispls, MPI_DOUBLE_PRECISION, &
& c_dist_pw, sendcount , sdispls, MPI_DOUBLE_PRECISION, comm, ierr )
IF( ierr /= 0 ) CALL errore( ' wf_redist ', ' mpi_alltoallv ', ierr )
END IF
DEALLOCATE( ctmp )
DEALLOCATE( rdispls, recvcount, sendcount, sdispls )
#endif
RETURN
END SUBROUTINE redistwfr
!=----------------------------------------------------------------------------=!
END MODULE mp_wave
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