DGESV doesn't use magma_dgetrs?

[jah87]

I was looking through the source for the magma_dgesv routine and noticed this:

Code: Select all

magma_dgetrf( n, n, A, lda, ipiv, info );
   94     if ( *info == 0 ) {
   95         lapackf77_dgetrs( MagmaNoTransStr, &n, &nrhs, A, &lda, ipiv, B, &ldb, info );
   96     }

There is not a magma_dgetrs routine being implemented?

[mgates3]

There is a GPU interface, magma_dgetrs_gpu, which is used in magma_dgesv_gpu. For the CPU interface, magma_dgesv, if the matrix is not already on the GPU, it can be slower to transfer it, perform getrs, and transfer the results back, since getrs does not parallelize well. We may change magma_dgesv internally to use magma_dgetrf_gpu and magma_dgetrs_gpu, but need to deal with cases when the matrix does not fit on the GPU (non-resident) or using multiple GPUs.

-mark