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 is expected to define precomputeQpResidual() and precomputeQpJacobian() instead of
      27             :  * computeQpResidual() and computeQpJacobian(). The signature of precomputeQpResidual() expected to
      28             :  * be defined in the derived class is as follows:
      29             :  *
      30             :  * @param qp The local quadrature point index
      31             :  * @param datum The ResidualDatum 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 precomputeQpResidual(const unsigned int qp,
      35             :  *                                           ResidualDatum & datum) const;
      36             :  *
      37             :  * The signature of precomputeQpJacobian() can be found in the code below. The definition of
      38             :  * computeQpOffDiagJacobian() is still the same with the original Kokkos kernel.
      39             :  */
      40             : template <typename Derived>
      41             : class KernelValue : public Kernel<Derived>
      42             : {
      43             :   usingKokkosKernelMembers(Derived);
      44             : 
      45             : public:
      46             :   static InputParameters validParams();
      47             : 
      48             :   /**
      49             :    * Constructor
      50             :    */
      51             :   KernelValue(const InputParameters & parameters);
      52             : 
      53             :   /**
      54             :    * Default methods to prevent compile errors even when these methods were not defined in the
      55             :    * derived class
      56             :    */
      57             :   ///@{
      58             :   /**
      59             :    * Compute diagonal Jacobian contribution on a quadrature point
      60             :    * @param j The trial function DOF index
      61             :    * @param qp The local quadrature point index
      62             :    * @param datum The ResidualDatum object of the current thread
      63             :    * @returns The component of the Jacobian contribution that will be multiplied by the test
      64             :    * function
      65             :    */
      66           0 :   KOKKOS_FUNCTION Real precomputeQpJacobian(const unsigned int /* j */,
      67             :                                             const unsigned int /* qp */,
      68             :                                             ResidualDatum & /* datum */) const
      69             :   {
      70           0 :     return 0;
      71             :   }
      72             :   ///@}
      73             : 
      74             :   /**
      75             :    * The parallel computation bodies that hide the base class methods to optimize for factoring
      76             :    * out the test function
      77             :    */
      78             :   ///@{
      79             :   KOKKOS_FUNCTION void computeResidualInternal(const Derived * kernel, ResidualDatum & datum) const;
      80             :   KOKKOS_FUNCTION void computeJacobianInternal(const Derived * kernel, ResidualDatum & datum) const;
      81             :   ///@}
      82             : 
      83             : protected:
      84             :   /**
      85             :    * Get whether precomputeQpJacobian() was not defined in the derived class
      86             :    * @returns Whether precomputeQpJacobian() was not defined in the derived class
      87             :    */
      88          10 :   virtual bool defaultJacobian() const override
      89             :   {
      90          10 :     return &Derived::precomputeQpJacobian == &KernelValue::precomputeQpJacobian;
      91             :   }
      92             : };
      93             : 
      94             : template <typename Derived>
      95             : InputParameters
      96        9132 : KernelValue<Derived>::validParams()
      97             : {
      98        9132 :   InputParameters params = Kernel<Derived>::validParams();
      99        9132 :   return params;
     100             : }
     101             : 
     102             : template <typename Derived>
     103          12 : KernelValue<Derived>::KernelValue(const InputParameters & parameters) : Kernel<Derived>(parameters)
     104             : {
     105          12 : }
     106             : 
     107             : template <typename Derived>
     108             : KOKKOS_FUNCTION void
     109          96 : KernelValue<Derived>::computeResidualInternal(const Derived * kernel, ResidualDatum & datum) const
     110             : {
     111          96 :   ResidualObject::computeResidualInternal(
     112             :       datum,
     113         192 :       [&](Real * local_re, const unsigned int ib, const unsigned int ie)
     114             :       {
     115         480 :         for (unsigned int qp = 0; qp < datum.n_qps(); ++qp)
     116             :         {
     117         384 :           datum.reinit();
     118             : 
     119         384 :           Real value = datum.JxW(qp) * kernel->precomputeQpResidual(qp, datum);
     120             : 
     121        1920 :           for (unsigned int i = ib; i < ie; ++i)
     122        1536 :             local_re[i] += value * _test(datum, i, qp);
     123             :         }
     124             :       });
     125          96 : }
     126             : 
     127             : template <typename Derived>
     128             : KOKKOS_FUNCTION void
     129          24 : KernelValue<Derived>::computeJacobianInternal(const Derived * kernel, ResidualDatum & datum) const
     130             : {
     131          24 :   Real value = 0;
     132             : 
     133          24 :   ResidualObject::computeJacobianInternal(
     134             :       datum,
     135          48 :       [&](Real * local_ke, const unsigned int ijb, const unsigned int ije)
     136             :       {
     137         120 :         for (unsigned int qp = 0; qp < datum.n_qps(); ++qp)
     138             :         {
     139          96 :           datum.reinit();
     140             : 
     141          96 :           unsigned int j_old = libMesh::invalid_uint;
     142             : 
     143        1632 :           for (unsigned int ij = ijb; ij < ije; ++ij)
     144             :           {
     145        1536 :             unsigned int i = ij % datum.n_jdofs();
     146        1536 :             unsigned int j = ij / datum.n_jdofs();
     147             : 
     148        1536 :             if (j != j_old)
     149             :             {
     150         384 :               value = datum.JxW(qp) * kernel->precomputeQpJacobian(j, qp, datum);
     151         384 :               j_old = j;
     152             :             }
     153             : 
     154        1536 :             local_ke[ij] += value * _test(datum, i, qp);
     155             :           }
     156             :         }
     157             :       });
     158          24 : }
     159             : 
     160             : } // namespace Kokkos
     161             : } // namespace Moose
     162             : 
     163             : #define usingKokkosKernelValueMembers(T) usingKokkosKernelMembers(T)