device_guard.hpp (5a15602)

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#ifndef SCHWARZ_DEVICE_GUARD_HPP_
#define SCHWARZ_DEVICE_GUARD_HPP_


#include <exception>

#include <schwarz/config.hpp>

#if SCHW_HAVE_CUDA
#include <cuda_runtime.h>
#endif


#include <exception_helpers.hpp>


namespace schwz {


class device_guard {
public:
    device_guard(int device_id)
    {
#if SCHW_HAVE_CUDA
        SCHWARZ_ASSERT_NO_CUDA_ERRORS(cudaGetDevice(&original_device_id));
        SCHWARZ_ASSERT_NO_CUDA_ERRORS(cudaSetDevice(device_id));
#endif
    }

    device_guard(device_guard &other) = delete;

    device_guard &operator=(const device_guard &other) = delete;

    device_guard(device_guard &&other) = delete;

    device_guard const &operator=(device_guard &&other) = delete;

    ~device_guard() noexcept(false)
    {
        /* Ignore the error during stack unwinding for this call */
        if (std::uncaught_exception()) {
#if SCHW_HAVE_CUDA
            cudaSetDevice(original_device_id);
#endif
        } else {
#if SCHW_HAVE_CUDA
            SCHWARZ_ASSERT_NO_CUDA_ERRORS(cudaSetDevice(original_device_id));
#endif
        }
    }

private:
    int original_device_id{};
};


}  // namespace schwz


#endif  // SCHWARZ_DEVICE_GUARD_HPP_