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OPENMP F90 / 95 Nested DO Loops - Issues Related to Improvement After Consistent Implementation

I did a few searches, but could not find anything similar to my question (sorry if my question is superfluous!). In any case, as the title says, I had problems with an improvement over the sequential implementation of my code. The code snippet I need to parallelize is as follows (this is Fortran90 with OpenMP):

do n=1,lm     
  do m=1,jm   
    do l=1,im      
      sum_u = 0
      sum_v = 0
      sum_t = 0
      do k=1,lm
       !$omp parallel do reduction (+:sum_u,sum_v,sum_t) 
        do j=1,jm  
          do i=1,im
            exp_smoother=exp(-(abs(i-l)/hzscl)-(abs(j-m)/hzscl)-(abs(k-n)/vscl))
            sum_u = sum_u + u_p(i,j,k) * exp_smoother
            sum_v = sum_v + v_p(i,j,k) * exp_smoother
            sum_t = sum_t + t_p(i,j,k) * exp_smoother

            sum_u_pert(l,m,n) = sum_u
            sum_v_pert(l,m,n) = sum_v
            sum_t_pert(l,m,n) = sum_t          

            end do
          end do
       end do      
    end do
  end do  
end do

Am I facing race conditions? Or am I just putting the directive in the wrong place? I am new to this, so I apologize if this is too simplistic a problem.

, , . , lm, jm im 60, 401 501. . ! xlf , .

! -Jen

+3
2

omp pragma .

(l, m, n) . (l, m, n) , . , ,

!$omp parallel do private(n,m,l,i,j,k,exp_smoother) shared(sum_u_pert,sum_v_pert,sum_t_pert,u_p,v_p,t_p), default(none)
do n=1,lm
  do m=1,jm
    do l=1,im
      do k=1,lm
        do j=1,jm
          do i=1,im
            exp_smoother=exp(-(abs(i-l)/hzscl)-(abs(j-m)/hzscl)-(abs(k-n)/vscl))
            sum_u_pert(l,m,n) = sum_u_pert(l,m,n) + u_p(i,j,k) * exp_smoother
            sum_v_pert(l,m,n) = sum_v_pert(l,m,n) + v_p(i,j,k) * exp_smoother
            sum_t_pert(l,m,n) = sum_t_pert(l,m,n) + t_p(i,j,k) * exp_smoother
          end do
        end do
      end do
    end do
  end do
end do

~ 6x 8 ( 20x41x41). , , , , 8- ; ; , im x jm x lm .

, , , , , ; , , - - .

+3

. N log2 (N) . N ^ 2. FFT, , , !

+2

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