possible to specify "stream" inside !$cuf kernel ?

Accelerated Computing HPC Compilers Legacy PGI Compilers
1

Hi,

I would like to know if there is any way to specify in a !cuf kernel directive that it must run the loop on a particular stream, because pgfortran refuses to compile the program below and reports a syntax error.

      program mysum
      use cudafor
      IMPLICIT NONE
      integer,parameter::n=13,nStreams=4
      integer :: stream(nStreams)
      real:: xx(n)
      real, device:: xx_dev(n)
      real val
      integer i,istat

      do i = 1, nStreams
        istat = cudaStreamCreate(stream(i))
      enddo

      write(*,*) stream

      do i=1,n
       xx(i)=real(i)
      enddo
      write(*,*) xx

      xx_dev=xx
      val = 0.0
!$cuf kernel do {{{ *, *, 0, stream(1) }}}
      do i=1,n
        val = val+xx_dev(i)
      enddo

      write(*,*) sum(xx),val
      end program mysum

thanks.
(Note: in the chevron syntax, please replace the curly braces with angle brackets because the angle brackets did not display the contents inside it correctly, which is probably some HTML issue)

2

Hi hajmola,

Currently, the CUF kernel directive does not allow for you to specify the stream. You will need to write your own kernels to use this functionality. However, I just added a feature request (TPR#18433) and sent it to our compiler engineers. Hopefully it’s something they can add for you.

  • Mat