Added initial version of a GEMM kernel selection tuner

1 files changed, 136 insertions, 0 deletions

diff --git a/src/tuning/routines/xgemm.cpp b/src/tuning/routines/xgemm.cpp
new file mode 100644
index 00000000..9590323a
--- /dev/null
+++ b/src/tuning/routines/xgemm.cpp
@@ -0,0 +1,136 @@
+
+// =================================================================================================
+// This file is part of the CLBlast project. The project is licensed under Apache Version 2.0. This
+// project loosely follows the Google C++ styleguide and uses a tab-size of two spaces and a max-
+// width of 100 characters per line.
+//
+// Author(s):
+//   Cedric Nugteren <www.cedricnugteren.nl>
+//
+// This file tunes the Xgemm routine at a high-level: choosing between the direct (single-kernel)
+// and the in-direct (kernel plus pre/post-processing) methods.
+//
+// =================================================================================================
+
+#include <exception>
+#include <string>
+#include <vector>
+#include <assert.h>
+
+#include "utilities/utilities.hpp"
+#include "utilities/timing.hpp"
+
+namespace clblast {
+// =================================================================================================
+
+template <typename T>
+void RunGemmRoutine(const size_t value, const Queue& queue, const std::vector<Buffer<T>>& buffers) {
+  auto queue_plain = queue();
+  auto event = cl_event{};
+  auto status = Gemm(Layout::kRowMajor, Transpose::kNo, Transpose::kNo,
+                     value, value, value, ConstantOne<T>(),
+                     buffers[0](), 0, value,
+                     buffers[1](), 0, value, ConstantOne<T>(),
+                     buffers[2](), 0, value,
+                     &queue_plain, &event);
+  if (status != StatusCode::kSuccess) {
+    throw RuntimeError("Gemm failed with status " + ToString(status));
+  }
+  clWaitForEvents(1, &event);
+  clReleaseEvent(event);
+}
+
+template <typename T>
+void ForceSelectIndirectFrom(const size_t minimum_size, const Device &device) {
+  const auto override_status = OverrideParameters(device(), "KernelSelection", PrecisionValue<T>(),
+                                                  {{"XGEMM_MIN_INDIRECT_SIZE", minimum_size}});
+  if (override_status != StatusCode::kSuccess) {
+    throw RuntimeError("OverrideParameters failed with status " + ToString(override_status));
+  }
+}
+
+template <typename T>
+void TuneXgemm(int argc, char* argv[]) {
+  auto command_line_args = RetrieveCommandLineArguments(argc, argv);
+  auto help = std::string{"* Options given/available:\n"};
+  const auto platform_id = GetArgument(command_line_args, help, kArgPlatform, ConvertArgument(std::getenv("CLBLAST_PLATFORM"), size_t{0}));
+  const auto device_id   = GetArgument(command_line_args, help, kArgDevice, ConvertArgument(std::getenv("CLBLAST_DEVICE"), size_t{0}));
+  const auto precision   = GetArgument(command_line_args, help, kArgPrecision, Precision::kSingle);
+  const auto num_runs    = GetArgument(command_line_args, help, kArgNumRuns, size_t{10});
+  fprintf(stdout, "%s\n", help.c_str());
+
+  // Values for m, n, and k
+  const auto from = size_t{64};
+  const auto to = size_t{1024};
+  const auto step = size_t{64};
+
+  // OpenCL initialisation
+  const auto platform = Platform(platform_id);
+  const auto device = Device(platform, device_id);
+  if (!PrecisionSupported<T>(device)) {
+    printf("* Unsupported precision, skipping this tuning run\n\n");
+    return;
+  }
+  const auto context = Context(device);
+  const auto queue = Queue(context, device);
+
+  // Buffers
+  auto a_mat = Buffer<T>(context, to * to);
+  auto b_mat = Buffer<T>(context, to * to);
+  auto c_mat = Buffer<T>(context, to * to);
+  auto buffers = std::vector<Buffer<T>>{a_mat, b_mat, c_mat};
+
+  // In-direct version
+  printf("[----------] Testing the in-direct GEMM routine for m=n=k\n");
+  ForceSelectIndirectFrom<T>(0, device);
+  const auto indirect = TimeRoutine(from, to, step, num_runs, queue, buffers, RunGemmRoutine<T>);
+
+  // Direct version
+  printf("[----------] Testing the direct GEMM routine for m=n=k\n");
+  ForceSelectIndirectFrom<T>(to * to * to + 1, device);
+  const auto direct = TimeRoutine(from, to, step, num_runs, queue, buffers, RunGemmRoutine<T>);
+
+  // Results
+  printf("[----------] Collecting results\n");
+  assert(indirect.size() == direct.size());
+  for (auto i = size_t{0}; i < indirect.size(); ++i) {
+    assert(indirect[i].first == direct[i].first);
+    const auto value = indirect[i].first;
+    const auto gflops_indirect = (2 * value * value * value) / (indirect[i].second * 1.0e6);
+    const auto gflops_direct = (2 * value * value * value) / (direct[i].second * 1.0e6);
+    printf("[ -------> ] %7zu %8.2lf %8.2lf\n", value, gflops_indirect, gflops_direct);
+  }
+
+  // Outputs the results as JSON to disk, including some meta-data
+  const auto precision_string = std::to_string(static_cast<size_t>(precision));
+  auto metadata = std::vector<std::pair<std::string,std::string>>{
+      {"kernel_family", "gemm_routine"},
+      {"precision", precision_string},
+  };
+  PrintTimingsToFileAsJSON("clblast_routine_gemm_" + precision_string + ".json",
+                           device, platform, metadata);
+
+}
+
+// =================================================================================================
+} // namespace clblast
+
+// Shortcuts to the clblast namespace
+using half = clblast::half;
+using float2 = clblast::float2;
+using double2 = clblast::double2;
+
+// Main function (not within the clblast namespace)
+int main(int argc, char *argv[]) {
+  const auto command_line_args = clblast::RetrieveCommandLineArguments(argc, argv);
+  switch(clblast::GetPrecision(command_line_args)) {
+    case clblast::Precision::kHalf: clblast::TuneXgemm<half>(argc, argv); break;
+    case clblast::Precision::kSingle: clblast::TuneXgemm<float>(argc, argv); break;
+    case clblast::Precision::kDouble: clblast::TuneXgemm<double>(argc, argv); break;
+    case clblast::Precision::kComplexSingle: clblast::TuneXgemm<float2>(argc, argv); break;
+    case clblast::Precision::kComplexDouble: clblast::TuneXgemm<double2>(argc, argv); break;
+  }
+  return 0;
+}
+
+// =================================================================================================