如何在C语言中获取Linux主机的GPU信息？

完全可行，不需要依赖lshw的输出解析，以下是几种实用的实现方式，按通用性和针对性分类：

1. 跨厂商通用方案：libdrm #

libdrm是Linux DRM（Direct Rendering Manager）的用户空间库，能直接与GPU驱动交互，获取硬件基础信息，支持NVIDIA、AMD、Intel等主流厂商的GPU。

示例代码 #

#include <drm/drm.h>
#include <drm/drm_mode.h>
#include <stdio.h>
#include <stdlib.h>

int main() {
    drmDevicePtr devices[64];
    int dev_count = drmGetDevices(devices, 64, 0);
    if (dev_count < 0) {
        perror("Failed to get DRM devices");
        return EXIT_FAILURE;
    }

    for (int i = 0; i < dev_count; i++) {
        drmDevicePtr dev = devices[i];
        printf("=== GPU %d ===\n", i);
        printf("品牌/型号: %s\n", dev->device_name);
        printf("PCI厂商ID: 0x%04x\n", dev->businfo.pci->vendor_id);
        printf("PCI设备ID: 0x%04x\n", dev->businfo.pci->device_id);

        // 查询显存大小
        uint64_t vram_size;
        if (drmGetClientCap(dev->fd, DRM_CLIENT_CAP_VRAM, &vram_size) == 0) {
            printf("总显存: %lu MB\n", vram_size / (1024 * 1024));
        }

        drmFreeDevice(&dev);
    }

    return EXIT_SUCCESS;
}

编译与运行 #

gcc -o gpu_info_drm gpu_info_drm.c -ldrm
sudo ./gpu_info_drm  # 或加入video组以无需root权限

2. NVIDIA专属方案：NVML #

NVIDIA Management Library（NVML）是官方提供的管理库，能获取NVIDIA GPU的详细信息（包括显存、温度、利用率等），可靠性高。

示例代码 #

#include <nvml.h>
#include <stdio.h>
#include <stdlib.h>

int main() {
    nvmlReturn_t ret = nvmlInit();
    if (ret != NVML_SUCCESS) {
        fprintf(stderr, "NVML初始化失败: %s\n", nvmlErrorString(ret));
        return EXIT_FAILURE;
    }

    unsigned int dev_count;
    ret = nvmlDeviceGetCount(&dev_count);
    if (ret != NVML_SUCCESS) {
        fprintf(stderr, "获取GPU数量失败: %s\n", nvmlErrorString(ret));
        nvmlShutdown();
        return EXIT_FAILURE;
    }

    for (unsigned int i = 0; i < dev_count; i++) {
        nvmlDevice_t dev;
        ret = nvmlDeviceGetHandleByIndex(i, &dev);
        if (ret != NVML_SUCCESS) {
            fprintf(stderr, "获取GPU %d句柄失败: %s\n", i, nvmlErrorString(ret));
            continue;
        }

        char gpu_name[NVML_DEVICE_NAME_BUFFER_SIZE];
        ret = nvmlDeviceGetName(dev, gpu_name, NVML_DEVICE_NAME_BUFFER_SIZE);
        if (ret == NVML_SUCCESS) {
            printf("=== NVIDIA GPU %d ===\n", i);
            printf("型号: %s\n", gpu_name);
        }

        nvmlMemory_t mem_info;
        ret = nvmlDeviceGetMemoryInfo(dev, &mem_info);
        if (ret == NVML_SUCCESS) {
            printf("总显存: %lu MB\n", mem_info.total / (1024 * 1024));
            printf("已用显存: %lu MB\n", mem_info.used / (1024 * 1024));
            printf("可用显存: %lu MB\n", mem_info.free / (1024 * 1024));
        }

        // 获取品牌系列
        nvmlDeviceAttribute_t brand;
        ret = nvmlDeviceGetAttribute(dev, NVML_ATTR_GPU_BRAND, &brand);
        if (ret == NVML_SUCCESS) {
            const char* brand_str;
            switch (brand) {
                case NVML_BRAND_GEFORCE: brand_str = "GeForce"; break;
                case NVML_BRAND_QUADRO: brand_str = "Quadro"; break;
                case NVML_BRAND_TESLA: brand_str = "Tesla"; break;
                default: brand_str = "Unknown"; break;
            }
            printf("品牌系列: %s\n", brand_str);
        }
    }

    nvmlShutdown();
    return EXIT_SUCCESS;
}

编译与运行 #

需要安装NVIDIA驱动及开发包（如nvidia-ml-dev）：

gcc -o gpu_info_nvml gpu_info_nvml.c -lnvidia-ml
./gpu_info_nvml

3. AMD专属方案：ADL #

Advanced Display Library（ADL）是AMD官方提供的库，用于获取AMD GPU的硬件信息和控制显示参数。

示例代码 #

#include <adl/adl.h>
#include <stdio.h>
#include <stdlib.h>

int main() {
    ADL_CONTEXT_HANDLE context;
    if (ADL_Main_Control_Create(ADL_Main_Memory_Alloc, 1) != ADL_OK) {
        fprintf(stderr, "ADL初始化失败\n");
        return EXIT_FAILURE;
    }
    if (ADL_Main_Control_GetContext(&context) != ADL_OK) {
        fprintf(stderr, "获取ADL上下文失败\n");
        ADL_Main_Control_Destroy();
        return EXIT_FAILURE;
    }

    int adapter_count;
    if (ADL_Adapter_NumberOfAdapters_Get(&adapter_count) != ADL_OK) {
        fprintf(stderr, "获取适配器数量失败\n");
        ADL_Main_Control_Destroy();
        return EXIT_FAILURE;
    }

    for (int i = 0; i < adapter_count; i++) {
        ADLAdapterInfo adapter_info;
        if (ADL_Adapter_Info_Get(i, &adapter_info) == ADL_OK) {
            printf("=== AMD GPU %d ===\n", i);
            printf("型号: %s\n", adapter_info.strAdapterName);
        }

        ADLDisplayMemoryInfo mem_info;
        if (ADL_Display_MemoryInfo_Get(i, 0, &mem_info) == ADL_OK) {
            printf("总显存: %lu MB\n", mem_info.ullTotalMemory / (1024 * 1024));
        }
    }

    ADL_Main_Control_Destroy();
    return EXIT_SUCCESS;
}

编译与运行 #

需要安装AMD驱动及ADL开发文件，编译时链接ADL库：

gcc -o gpu_info_adl gpu_info_adl.c -ladl
./gpu_info_adl

4. 无额外库方案：读取sysfs #

Linux的sysfs文件系统暴露了硬件的详细信息，无需依赖任何第三方库，直接读取/sys/class/drm/下的文件即可获取GPU信息。

示例代码 #

#include <stdio.h>
#include <dirent.h>
#include <string.h>
#include <stdlib.h>

#define SYSFS_DRM_PATH "/sys/class/drm/"

int main() {
    DIR* drm_dir = opendir(SYSFS_DRM_PATH);
    if (!drm_dir) {
        perror("Failed to open DRM sysfs directory");
        return EXIT_FAILURE;
    }

    struct dirent* entry;
    while ((entry = readdir(drm_dir)) != NULL) {
        if (strncmp(entry->d_name, "card", 4) == 0) {
            char file_path[256];
            printf("=== %s ===\n", entry->d_name);

            // 读取厂商ID
            snprintf(file_path, sizeof(file_path), "%s%s/device/vendor", SYSFS_DRM_PATH, entry->d_name);
            FILE* f = fopen(file_path, "r");
            if (f) {
                unsigned int vendor_id;
                fscanf(f, "%x", &vendor_id);
                fclose(f);

                printf("品牌: ");
                switch (vendor_id) {
                    case 0x10de: printf("NVIDIA\n"); break;
                    case 0x1002: printf("AMD\n"); break;
                    case 0x8086: printf("Intel\n"); break;
                    default: printf("Unknown (0x%04x)\n", vendor_id); break;
                }
            }

            // 读取型号名称
            snprintf(file_path, sizeof(file_path), "%s%s/device/name", SYSFS_DRM_PATH, entry->d_name);
            f = fopen(file_path, "r");
            if (f) {
                char name[256];
                fgets(name, sizeof(name), f);
                fclose(f);
                name[strcspn(name, "\n")] = '\0';
                printf("型号: %s\n", name);
            }

            // 读取显存大小
            snprintf(file_path, sizeof(file_path), "%s%s/device/mem_info/vram_total", SYSFS_DRM_PATH, entry->d_name);
            f = fopen(file_path, "r");
            if (f) {
                unsigned long long vram_total;
                fscanf(f, "%llu", &vram_total);
                fclose(f);
                printf("总显存: %llu MB\n", vram_total / (1024 * 1024));
            }
        }
    }

    closedir(drm_dir);
    return EXIT_SUCCESS;
}

编译与运行 #

gcc -o gpu_info_sysfs gpu_info_sysfs.c
./gpu_info_sysfs  # 普通用户即可读取

内容的提问来源于stack exchange，提问作者Ar Rakin