Method onCreate

source/backend/cpu/CPUBackend.cpp:267–357

}

Backend* CPURuntime::onCreate(const BackendConfig* config, Backend* origin) const {
    {
        mCpuIds = hint().cpuIds;
        _validateCpuIds();
        mCpuMask = MNNGetCPUMask(mCpuIds);
        _resetThreadPool();
    }
    if (hint().midMemoryPath.size() > 0) {
        if (mDynamicMmap.empty()) {
            // Only support set featuremap dir once
            mDynamicMmap.resize(2);
            auto mmapMem = BufferAllocator::Allocator::createMmap(hint().midMemoryPath.c_str(), "", "dynamic");
            for (auto& buf : mDynamicMmap) {
                buf.root = mmapMem;
            }
        }
    }
    if (hint().weightMemoryPath.size() > 0) {
        // forward_type, precision_type, memory_type, power_type
        std::string prefix = "0_0_0_0_";
        prefix[2] += mPrecision;
        prefix[4] += mMemory;
        prefix[6] += mPower;
        // prefix += hint().modelUUID + "_";
        bool autoRemove = true;
        bool syncValid = false;
        if (hint().useCachedMmap) {
            autoRemove = false;
            std::string fileName = MNNFilePathConcat(hint().weightMemoryPath, prefix + "sync.static");
            syncValid = MNNFileExist(fileName.c_str());
            const_cast<RuntimeHint&>(hint()).useCachedMmap += syncValid;
        }
        if (nullptr == mStaticAllocatorMMap.get()) {
            // Only support set weightmap dir once
            mStaticAllocatorRaw = mStaticAllocator;
            auto mmapMem = BufferAllocator::Allocator::createMmap(hint().weightMemoryPath.c_str(), prefix.c_str(), "static", autoRemove, syncValid);
            size_t mmapSize = static_cast<size_t>(hint().mmapFileSize) * 1024 * 1024;
            mStaticAllocator.reset(new EagerBufferAllocator(mmapMem, 32, mmapSize));
            mStaticAllocatorMMap = mStaticAllocator;
        }
    }
    auto precision = mPrecision;
    auto memory = mMemory;
    size_t flags = mFlags;
    if (nullptr != origin) {
        auto cpuBn = static_cast<CPUBackend*>(origin);
        mSharedDmaInfo = cpuBn->mDmaInfo;
    }
    if (nullptr != config) {
        precision = config->precision;
        flags = config->flags;
        memory = config->memory;
    }
#ifdef LOG_VERBOSE
    MNN_PRINT("cpu backend was created by runtime:%p\n", this);
#endif
    CPUBackend* res = nullptr;
    auto initThreadNumber = hint().initThreadNumber;