Averager.h

Go to the documentation of this file.

/***********************************************************************************************************************
*                                                                                                                      *
* libscopehal                                                                                                          *
*                                                                                                                      *
* Copyright (c) 2012-2026 Andrew D. Zonenberg and contributors                                                         *
* All rights reserved.                                                                                                 *
*                                                                                                                      *
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the     *
* following conditions are met:                                                                                        *
*                                                                                                                      *
*    * Redistributions of source code must retain the above copyright notice, this list of conditions, and the         *
*      following disclaimer.                                                                                           *
*                                                                                                                      *
*    * 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.                *
*                                                                                                                      *
*    * Neither the name of the author nor the names of any contributors may be used to endorse or promote products     *
*      derived from this software without specific prior written permission.                                           *
*                                                                                                                      *
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS "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 *
* THE AUTHORS BE HELD 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.                                                                                          *
*                                                                                                                      *
***********************************************************************************************************************/
 
#ifndef Averager_h
#define Averager_h
 
struct __attribute__((packed)) ReductionSumPushConstants
{
    uint32_t numSamples;
    uint32_t numThreads;
    uint32_t samplesPerThread;
};
 
class Averager
{
public:
    Averager();
 
    template<class T>
    __attribute__((noinline))
    float Average(
        T* wfm,
        vk::raii::CommandBuffer& cmdBuf,
        std::shared_ptr<QueueHandle> queue)
    {
        AssertTypeIsAnalogWaveform(wfm);
 
        //This value experimentally gives the best speedup for an NVIDIA 2080 Ti vs an Intel Xeon Gold 6144
        //Maybe consider dynamic tuning in the future at initialization?
        const uint64_t numThreads = 16384;
 
        cmdBuf.begin({});
 
        //Do the reduction summation
        size_t depth = wfm->size();
        ReductionSumPushConstants push;
        push.numSamples = depth;
        push.numThreads = numThreads;
        push.samplesPerThread = (depth + numThreads) / numThreads;
        m_temporaryResults.resize(numThreads);
 
        m_computePipeline->BindBufferNonblocking(0, m_temporaryResults, cmdBuf, true);
        m_computePipeline->BindBufferNonblocking(1, wfm->m_samples, cmdBuf);
        m_computePipeline->Dispatch(cmdBuf, push, numThreads, 1);
 
        m_temporaryResults.MarkModifiedFromGpu();
 
        cmdBuf.end();
        queue->SubmitAndBlock(cmdBuf);
 
        //Do the final summation
        m_temporaryResults.PrepareForCpuAccess();
        float finalSum = 0;
        for(uint64_t i=0; i<numThreads; i++)
            finalSum += m_temporaryResults[i];
 
        return finalSum / depth;
    }
 
protected:
    std::unique_ptr<ComputePipeline> m_computePipeline;
 
    AcceleratorBuffer<float> m_temporaryResults;
};
 
#endif