cuda_compute_capability.c

/*
* Copyright (C) 2011 Florian Rathgeber, florian.rathgeber@gmail.com
*
* This code is licensed under the MIT License.  See the FindCUDA.cmake script
* for the text of the license.
*
* Based on code by Christopher Bruns published on Stack Overflow (CC-BY):
* http://stackoverflow.com/questions/2285185
*/

#include <stdio.h>
#include <cuda_runtime.h>

int main() {
	int deviceCount, device, major = 9999, minor = 9999;
	int gpuDeviceCount = 0;
	struct cudaDeviceProp properties;

	if (cudaGetDeviceCount(&deviceCount) != cudaSuccess)
	{
		printf("Couldn't get device count: %s\n", cudaGetErrorString(cudaGetLastError()));
		return 1;
	}
	/* machines with no GPUs can still report one emulation device */
	for (device = 0; device < deviceCount; ++device) {
		cudaGetDeviceProperties(&properties, device);
		if (properties.major != 9999) {/* 9999 means emulation only */
			++gpuDeviceCount;
			/*  get minimum compute capability of all devices */
			if (major > properties.major) {
				major = properties.major;
				minor = properties.minor;
			} else if (minor > properties.minor) {
				minor = properties.minor;
			}
		}
	}

	/* don't just return the number of gpus, because other runtime cuda
	errors can also yield non-zero return values */
	if (gpuDeviceCount > 0) {
		if (major == 2 && minor == 1)
		{
			// There is no --arch compute_21 flag for nvcc, so force minor to 0
			minor = 0;
		}
		/* this output will be parsed by FindCUDA.cmake */
		printf("%d%d", major, minor);
		return 0; /* success */
	}
	return 1; /* failure */
}