Add fast two-level mode N GEMV

Very close to cublas in performance, with LayoutLeft or LayoutRight.
(~100 gflops for 1e5 * 1e5 double matrix on V100)

perf_test/blas/CMakeLists.txt

@@ -1,2 +1,3 @@
 ADD_SUBDIRECTORY(blas)
+ADD_SUBDIRECTORY(blas2)
 ADD_SUBDIRECTORY(blas3)

perf_test/blas/blas2/CMakeLists.txt

@@ -0,0 +1,7 @@
+KOKKOSKERNELS_INCLUDE_DIRECTORIES(${CMAKE_CURRENT_BINARY_DIR})
+KOKKOSKERNELS_INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR})
+
+KOKKOSKERNELS_ADD_EXECUTABLE(
+    KokkosBlas2_gemv_perf_test
+    SOURCES KokkosBlas2_gemv_perf_test.cpp
+)

perf_test/blas/blas2/KokkosBlas2_gemv_perf_test.cpp

@@ -0,0 +1,204 @@
+/*
+//@HEADER
+// ************************************************************************
+//
+//                        Kokkos v. 3.0
+//       Copyright (2020) National Technology & Engineering
+//               Solutions of Sandia, LLC (NTESS).
+//
+// Under the terms of Contract DE-NA0003525 with NTESS,
+// the U.S. Government retains certain rights in this software.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// 1. Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the distribution.
+//
+// 3. Neither the name of the Corporation nor the names of the
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY NTESS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL NTESS OR THE
+// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Questions? Contact Siva Rajamanickam (srajama@sandia.gov)
+//
+// ************************************************************************
+//@HEADER
+*/
+
+#include "KokkosBlas2_gemv.hpp"
+#include <Kokkos_Random.hpp>
+
+struct Params
+{
+  int use_cuda = 0;
+  int use_openmp = 0;
+  int use_threads = 0;
+  int m = 5000;
+  int n = 5000;
+  int repeat = 1;
+  bool layoutLeft = true;
+};
+
+void print_options(){
+  std::cerr << "Options\n" << std::endl;
+
+  std::cerr << "\tBACKEND: '--threads[numThreads]' | '--openmp [numThreads]' | '--cuda [cudaDeviceIndex]'" << std::endl;
+  std::cerr << "\tIf none selected, serial is used." << std::endl;
+  std::cerr << "\t[Optional] --repeat :: how many times to repeat overall spadd (symbolic + repeated numeric)" << std::endl;
+  std::cerr << "\t[Optional] --layout :: matrix layout ('left' or 'right', default 'left')" << std::endl;
+  std::cerr << "\t[Optional] --m      :: number of rows to generate" << std::endl;
+  std::cerr << "\t[Optional] --n      :: number of cols to generate" << std::endl;
+}
+
+int parse_inputs (Params& params, int argc, char **argv){
+  for ( int i = 1 ; i < argc ; ++i ) {
+    if ( 0 == strcasecmp( argv[i] , "--help") || 0 == strcasecmp( argv[i] , "-h" )) {
+      print_options();
+      exit(0);  //note: this is before Kokkos::initialize
+    }
+    else if ( 0 == strcasecmp( argv[i] , "--threads" ) ) {
+      params.use_threads = atoi( argv[++i] );
+    }
+    else if ( 0 == strcasecmp( argv[i] , "--openmp" ) ) {
+      params.use_openmp = atoi( argv[++i] );
+    }
+    else if ( 0 == strcasecmp( argv[i] , "--cuda" ) ) {
+      params.use_cuda = atoi( argv[++i] ) + 1;
+    }
+    else if ( 0 == strcasecmp( argv[i] , "--layout" ) ) {
+      i++;
+      if(0 == strcasecmp( argv[i] , "left"))
+        params.layoutLeft = true;
+      else if(0 == strcasecmp( argv[i] , "right"))
+        params.layoutLeft = false;
+      else
+      {
+        std::cerr << "Invalid layout: must be 'left' or 'right'.\n";
+        exit(1);
+      }
+    }
+    else if( 0 == strcasecmp( argv[i], "--m" ))
+    {
+      params.m = atoi(argv[++i]);
+    }
+    else if( 0 == strcasecmp( argv[i], "--n" ))
+    {
+      params.n = atoi(argv[++i]);
+    }
+    else if ( 0 == strcasecmp( argv[i] , "--repeat" ) ) {
+      //if provided, C will be written to given file.
+      //has to have ".bin", or ".crs" extension.
+      params.repeat = atoi( argv[++i] );
+    }
+    else {
+      std::cerr << "Unrecognized command line argument #" << i << ": " << argv[i] << std::endl ;
+      print_options();
+      return 1;
+    }
+  }
+  return 0;
+}
+
+template<typename ExecSpace, typename Layout>
+void run(int m, int n, int repeat)
+{
+  using Scalar = double;
+  using MemSpace = typename ExecSpace::memory_space;
+  using Device = Kokkos::Device<ExecSpace, MemSpace>;
+  std::cout << "Running GEMV experiment (" << ExecSpace::name() << ")\n";
+  Kokkos::View<Scalar**, Layout, Device> A(Kokkos::ViewAllocateWithoutInitializing("A"), m, n);
+  Kokkos::View<Scalar*, Device> x(Kokkos::ViewAllocateWithoutInitializing("x"), n);
+  Kokkos::View<Scalar*, Device> y(Kokkos::ViewAllocateWithoutInitializing("y"), m);
+  Kokkos::Random_XorShift64_Pool<ExecSpace> pool(123);
+  Kokkos::fill_random(A, pool, 10.0);
+  Kokkos::fill_random(x, pool, 10.0);
+  //Do a warm-up run
+  KokkosBlas::gemv("N", 1.0, A, x, 0.0, y);
+  //Now, start timing
+  Kokkos::fence();
+  Kokkos::Timer timer;
+  for(int i = 0; i < repeat; i++)
+  {
+    KokkosBlas::gemv("N", 1.0, A, x, 0.0, y);
+    ExecSpace().fence();
+  }
+  double total = timer.seconds();
+  double avg = total / repeat;
+  size_t flopsPerRun = (size_t) m * n;
+  printf("Avg GEMV time: %f s.\n", avg);
+  printf("Avg GEMV FLOP/s: %.3e\n", flopsPerRun / avg);
+}
+
+int main (int argc, char ** argv){
+  Params params;
+
+  if (parse_inputs (params, argc, argv) ){
+    return 1;
+  }
+  const int num_threads = params.use_openmp; // Assumption is that use_openmp variable is provided as number of threads
+  const int device_id = params.use_cuda - 1;
+
+  Kokkos::initialize( Kokkos::InitArguments( num_threads, -1, device_id ) );
+
+  bool useOMP = params.use_openmp != 0;
+  bool useCUDA = params.use_cuda != 0;
+
+  bool useSerial = !useOMP && !useCUDA;
+
+  if(useOMP)
+  {
+#if defined( KOKKOS_ENABLE_OPENMP )
+    if(params.layoutLeft)
+      run<Kokkos::OpenMP, Kokkos::LayoutLeft>(params.m, params.n, params.repeat);
+    else
+      run<Kokkos::OpenMP, Kokkos::LayoutRight>(params.m, params.n, params.repeat);
+#else
+    std::cout << "ERROR: OpenMP requested, but not available.\n";
+    return 1;
+#endif
+  }
+  if(useCUDA)
+  {
+#if defined( KOKKOS_ENABLE_CUDA )
+    if(params.layoutLeft)
+      run<Kokkos::Cuda, Kokkos::LayoutLeft>(params.m, params.n, params.repeat);
+    else
+      run<Kokkos::Cuda, Kokkos::LayoutRight>(params.m, params.n, params.repeat);
+#else
+    std::cout << "ERROR: CUDA requested, but not available.\n";
+    return 1;
+#endif
+  }
+  if(useSerial)
+  {
+#if defined( KOKKOS_ENABLE_SERIAL )
+    if(params.layoutLeft)
+      run<Kokkos::Serial, Kokkos::LayoutLeft>(params.m, params.n, params.repeat);
+    else
+      run<Kokkos::Serial, Kokkos::LayoutRight>(params.m, params.n, params.repeat);
+#else
+    std::cout << "ERROR: Serial device requested, but not available.\n";
+    return 1;
+#endif
+  }
+  Kokkos::finalize(); 
+  return 0;
+}
+