Line data    Source code

       1             : //* This file is part of the MOOSE framework
       2             : //* https://www.mooseframework.org
       3             : //*
       4             : //* All rights reserved, see COPYRIGHT for full restrictions
       5             : //* https://github.com/idaholab/moose/blob/master/COPYRIGHT
       6             : //*
       7             : //* Licensed under LGPL 2.1, please see LICENSE for details
       8             : //* https://www.gnu.org/licenses/lgpl-2.1.html
       9             : 
      10             : #pragma once
      11             : 
      12             : #include "KokkosKernel.h"
      13             : 
      14             : namespace Moose
      15             : {
      16             : namespace Kokkos
      17             : {
      18             : 
      19             : /**
      20             :  * The base class for a user to derive their own Kokkos kernels where the residual is of the form
      21             :  *
      22             :  * $(\dots, \psi_i)$
      23             :  *
      24             :  * i.e. the test function $(\psi_i)$ can be factored out for optimization.
      25             :  *
      26             :  * The user should still define computeQpResidual() and computeQpJacobian(), but their signatures
      27             :  * are different from the base class. The signature of computeQpResidual() expected to be defined in
      28             :  * the derived class is as follows:
      29             :  *
      30             :  * @param qp The local quadrature point index
      31             :  * @param datum The AssemblyDatum object of the current thread
      32             :  * @returns The component of the residual contribution that will be multiplied by the test function
      33             :  *
      34             :  * KOKKOS_FUNCTION Real computeQpResidual(const unsigned int qp,
      35             :  *                                        AssemblyDatum & datum) const;
      36             :  *
      37             :  * The signature of computeQpJacobian() can be found in the code below. The definition of
      38             :  * computeQpOffDiagJacobian() is still the same with the original Kokkos kernel.
      39             :  */
      40             : class KernelValue : public Kernel
      41             : {
      42             : public:
      43             :   static InputParameters validParams();
      44             : 
      45             :   /**
      46             :    * Constructor
      47             :    */
      48             :   KernelValue(const InputParameters & parameters);
      49             : 
      50             :   /**
      51             :    * Default methods to prevent compile errors even when these methods were not defined in the
      52             :    * derived class
      53             :    */
      54             :   ///@{
      55             :   /**
      56             :    * Compute diagonal Jacobian contribution on a quadrature point
      57             :    * @param j The trial function DOF index
      58             :    * @param qp The local quadrature point index
      59             :    * @param datum The AssemblyDatum object of the current thread
      60             :    * @returns The component of the Jacobian contribution that will be multiplied by the test
      61             :    * function
      62             :    */
      63           0 :   KOKKOS_FUNCTION Real computeQpJacobian(const unsigned int /* j */,
      64             :                                          const unsigned int /* qp */,
      65             :                                          AssemblyDatum & /* datum */) const
      66             :   {
      67           0 :     return 0;
      68             :   }
      69             :   /**
      70             :    * Get the function pointer of the default computeQpJacobian()
      71             :    * @returns The function pointer
      72             :    */
      73       37638 :   static auto defaultJacobian() { return &KernelValue::computeQpJacobian; }
      74             :   ///@}
      75             : 
      76             :   /**
      77             :    * Shims for hook methods that can be leveraged to implement static polymorphism
      78             :    */
      79             :   ///{@
      80             :   template <typename Derived>
      81         384 :   KOKKOS_FUNCTION Real computeQpResidualShim(const Derived & kernel,
      82             :                                              const unsigned int qp,
      83             :                                              AssemblyDatum & datum) const
      84             :   {
      85         384 :     return kernel.computeQpResidual(qp, datum);
      86             :   }
      87             :   template <typename Derived>
      88         384 :   KOKKOS_FUNCTION Real computeQpJacobianShim(const Derived & kernel,
      89             :                                              const unsigned int j,
      90             :                                              const unsigned int qp,
      91             :                                              AssemblyDatum & datum) const
      92             :   {
      93         384 :     return kernel.computeQpJacobian(j, qp, datum);
      94             :   }
      95             :   ///@}
      96             : 
      97             :   /**
      98             :    * The parallel computation bodies that hide the base class methods to optimize for factoring
      99             :    * out the test function
     100             :    */
     101             :   ///@{
     102             :   template <typename Derived>
     103             :   KOKKOS_FUNCTION void computeResidualInternal(const Derived & kernel, AssemblyDatum & datum) const;
     104             :   template <typename Derived>
     105             :   KOKKOS_FUNCTION void computeJacobianInternal(const Derived & kernel, AssemblyDatum & datum) const;
     106             :   ///@}
     107             : };
     108             : 
     109             : template <typename Derived>
     110             : KOKKOS_FUNCTION void
     111          96 : KernelValue::computeResidualInternal(const Derived & kernel, AssemblyDatum & datum) const
     112             : {
     113          96 :   ResidualObject::computeResidualInternal(
     114             :       datum,
     115         192 :       [&](Real * local_re, const unsigned int ib, const unsigned int ie)
     116             :       {
     117         480 :         for (unsigned int qp = 0; qp < datum.n_qps(); ++qp)
     118             :         {
     119         384 :           datum.reinit();
     120             : 
     121         384 :           Real value = datum.JxW(qp) * kernel.computeQpResidualShim(kernel, qp, datum);
     122             : 
     123        1920 :           for (unsigned int i = ib; i < ie; ++i)
     124        1536 :             local_re[i] += value * _test(datum, i, qp);
     125             :         }
     126             :       });
     127          96 : }
     128             : 
     129             : template <typename Derived>
     130             : KOKKOS_FUNCTION void
     131          24 : KernelValue::computeJacobianInternal(const Derived & kernel, AssemblyDatum & datum) const
     132             : {
     133          24 :   Real value = 0;
     134             : 
     135          24 :   ResidualObject::computeJacobianInternal(
     136             :       datum,
     137          48 :       [&](Real * local_ke, const unsigned int ijb, const unsigned int ije)
     138             :       {
     139         120 :         for (unsigned int qp = 0; qp < datum.n_qps(); ++qp)
     140             :         {
     141          96 :           datum.reinit();
     142             : 
     143          96 :           unsigned int j_old = libMesh::invalid_uint;
     144             : 
     145        1632 :           for (unsigned int ij = ijb; ij < ije; ++ij)
     146             :           {
     147        1536 :             unsigned int i = ij % datum.n_jdofs();
     148        1536 :             unsigned int j = ij / datum.n_jdofs();
     149             : 
     150        1536 :             if (j != j_old)
     151             :             {
     152         384 :               value = datum.JxW(qp) * kernel.computeQpJacobianShim(kernel, j, qp, datum);
     153         384 :               j_old = j;
     154             :             }
     155             : 
     156        1536 :             local_ke[ij] += value * _test(datum, i, qp);
     157             :           }
     158             :         }
     159             :       });
     160          24 : }
     161             : 
     162             : } // namespace Kokkos
     163             : } // namespace Moose