复制由cudaMallocPitch分配的内存

Question

可以使用cudaMemcpy分配与cudaMallocPitch分配的内存吗？如果不是，你能告诉，应该使用哪个函数。 cudaMallocPitch返回线性内存，所以我想应该使用cudaMemcpy。

Answer 1

您当然可以使用cudaMemcpy复制倾斜的设备内存，但使用cudaMemcpy2D更为常用。从主机到设备投副本的一个例子是这个样子：

#include "cuda.h" 
#include <assert.h> 

typedef float real; 

int main(void) 
{ 

    cudaFree(0); // Establish context 

    // Host array dimensions 
    const size_t dx = 300, dy = 300; 

    // For the CUDA API width and pitch are specified in bytes 
    size_t width = dx * sizeof(real), height = dy; 

    // Host array allocation 
    real * host = new real[dx * dy]; 
    size_t pitch1 = dx * sizeof(real); 

    // Device array allocation 
    // pitch is determined by the API call 
    real * device; 
    size_t pitch2; 
    assert(cudaMallocPitch((real **)&device, &pitch2, width, height) == cudaSuccess); 

    // Sample memory copy - note source and destination pitches can be different 
    assert(cudaMemcpy2D(device, pitch2, host, pitch1, width, height, cudaMemcpyHostToDevice) == cudaSuccess); 

    // Destroy context 
    assert(cudaDeviceReset() == cudaSuccess); 

    return 0; 
} 

（注：未经测试，cavaet自负和所有.....）