prefetch.hpp

/*
 * Copyright (c) 2024, NVIDIA CORPORATION.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 
#pragma once
 
#include <cudf/utilities/default_stream.hpp>
 
#include <rmm/device_uvector.hpp>
 
#include <map>
#include <shared_mutex>
#include <string>
#include <string_view>
 
namespace CUDF_EXPORT cudf {
namespace experimental::prefetch {
 
namespace detail {
 
class prefetch_config {
 public:
  prefetch_config& operator=(const prefetch_config&) = delete;
  prefetch_config(const prefetch_config&)            = delete;
 
  static prefetch_config& instance();
 
  bool get(std::string_view key);
  void set(std::string_view key, bool value);
  bool debug{false};
 
 private:
  prefetch_config() = default;                //< Private constructor to enforce singleton pattern
  std::map<std::string, bool> config_values;  //< Map of configuration keys to values
  std::shared_mutex config_mtx;               //< Mutex for thread-safe config access
};
 
void prefetch(std::string_view key,
              void const* ptr,
              std::size_t size,
              rmm::cuda_stream_view stream,
              rmm::cuda_device_id device_id = rmm::get_current_cuda_device());
 
cudaError_t prefetch_noexcept(
  std::string_view key,
  void const* ptr,
  std::size_t size,
  rmm::cuda_stream_view stream,
  rmm::cuda_device_id device_id = rmm::get_current_cuda_device()) noexcept;
 
template <typename T>
void prefetch(std::string_view key,
              rmm::device_uvector<T> const& v,
              rmm::cuda_stream_view stream,
              rmm::cuda_device_id device_id = rmm::get_current_cuda_device())
{
  if (v.is_empty()) { return; }
  prefetch(key, v.data(), v.size(), stream, device_id);
}
 
}  // namespace detail
 
void enable_prefetching(std::string_view key);
 
void disable_prefetching(std::string_view key);
 
void prefetch_debugging(bool enable);
 
}  // namespace experimental::prefetch
}  // namespace CUDF_EXPORT cudf