内核多线程测试内存工具

0.1写了一个小工具，多线程测试内存拷贝性能，运行于内核态，加载模块即可运行测试，卸载模块即停止，初步的一个版本，后续有时间继续改进，线程数和每次拷贝的内存大小都可以设定。

0.2增加了命令行交互功能，通过ioctl系统调用进行用户空间和内核空间的数据交换。

#include "test_mem.h"#include<linux/sched.h>#include<linux/slab.h>#include<linux/wait.h>MODULE_LICENSE("Dual BSD/GPL");#define TMEM_VERSION "0.0.1" #define CPUHZ 26 /*bandwidth result should divide 100000000 to get MB/S*/#define TEST_TIME 10 #define BUF_SIZE 128*1024*1024 static int flag = 0;static int tflag = 0;static DECLARE_WAIT_QUEUE_HEAD(wq);static struct task_struct *_tsk; static struct mutex ioctl_mutex;static struct mutex count_mutex;static struct para pa;static unsigned long total_count = 0,total_nr = 0;static unsigned long start_time = 0,end_time = 0; static __inline__ __u64 rdtsc(void) {    __u32 lo,hi;    __asm__ __volatile__    (       "rdtsc":"=a"(lo),"=d"(hi)    );    return (__u64)hi<<32|lo;}static int calcu_thread(void *data){    unsigned long total_copysize,total_test_time;    int total_average_bandwidth,total_average_copy_time,total_average_copy_time2;        while(true)    {if(tflag == 0)break;        schedule();    }     total_copysize = pa.copysize*total_count/1024/1024;    total_test_time = (end_time - start_time)/CPUHZ;    total_average_bandwidth = total_copysize*100000000/total_test_time;     total_average_copy_time = total_test_time/total_count/100;    total_average_copy_time2 = total_test_time*10/total_count;        printk("TOTAL:copy size:%luMB test time:%lums copy counts:%lu\n",             total_copysize,total_test_time/100000,total_count);    printk("TOTAL:bandwidth:%dMB/s copy time once:%dus %dns\n",                          total_average_bandwidth,total_average_copy_time,             total_average_copy_time2);        return 0;}static int test_thread(void *data){    char *b_wtemp,*b_rtemp;    char *buf_read,*buf_write;     unsigned long int num_rd,start_t,end_t,count = 0,count_t = 0;    unsigned long start, t_copy_time_once,t_copy_time_once2,intv=TEST_TIME*HZ,                  t_copy_time,t_bandwidth,t_bandwidth2;    buf_read = vmalloc(BUF_SIZE);    buf_write = vmalloc(BUF_SIZE);    b_rtemp = buf_read;    b_wtemp = buf_write;    if(!buf_read || !buf_write)    {    TMEMERR("failed to allocate memory");    }    wait_event_interruptible(wq,flag != 0);    start = jiffies;    start_t = rdtsc();    do{       memcpy(b_rtemp,b_wtemp,pa.copysize);       count++;       count_t++;       b_rtemp += pa.copysize;       b_wtemp += pa.copysize;       if((count_t+1)*pa.copysize> BUF_SIZE)       {          count_t = 0;          b_rtemp = buf_read;          b_wtemp = buf_write;       }     }while((flag != 0) && time_before(jiffies, start+intv));     end_t = rdtsc();     num_rd = end_t - start_t;     vfree(buf_read);     vfree(buf_write);     mutex_lock(&count_mutex);     total_count += count;     mutex_unlock(&count_mutex);     tflag--;     if(tflag == 0)end_time = rdtsc();     t_copy_time_once = num_rd/CPUHZ/count/100;/*us*/     t_copy_time_once2 = num_rd*10/CPUHZ/count;/*ns*/     t_copy_time = num_rd/CPUHZ/100;          t_bandwidth = pa.copysize*CPUHZ*count*100000000/1024/1024/num_rd;     t_bandwidth2 = pa.copysize*count*1000000/t_copy_time/1024/1024;          printk("%lu,%lu,%lu,%lu\n",count,t_copy_time_once,t_copy_time_once2,t_bandwidth2);     return 0;}static long tmem_ioctl(struct file *file,unsigned int cmd,unsigned long arg){    int ret = 0,i;    total_count = 0;    total_nr = 0;    flag = 0;    mutex_lock(&ioctl_mutex);    switch(cmd)    {       case TMEM_RUN:          /* name = kmalloc(20*sizeof(char),GFP_KERNEL);*/           if (copy_from_user       (&pa,(struct para __user *)arg, sizeof(pa)))                {                    ret = -EFAULT;           break;       }           printk("thread run time:%ds copy size:%lu threads:%d\n",TEST_TIME,                     pa.copysize,pa.threads);           tflag = pa.threads;          /* #pragma omp parallel for*/           for(i = 0;i != pa.threads;i++)           {              /*sprintf(name,"thread_name:%d",i);*/              _tsk = kthread_create(test_thread,NULL,"test_thread");              if (IS_ERR(_tsk))               {                  ret = PTR_ERR(_tsk);                  _tsk = NULL;                  goto out;              }               wake_up_process(_tsk);            }            _tsk = kthread_create(calcu_thread,NULL,"calu_thread");            if (IS_ERR(_tsk))            {                ret = PTR_ERR(_tsk);                _tsk = NULL;                goto out;            }            wake_up_process(_tsk);            schedule_timeout(2*HZ);            flag = 1;            wake_up_interruptible(&wq);            start_time = rdtsc();            break;         case TMEM_STOP:            TMEMINFO("COMMAND STOP!");            break;          default:            TMEMERR("UNKNOW COMMAND IN KERNEL");    }         out:    mutex_unlock(&ioctl_mutex);    return ret;}/*static ssize_t tmem_read(struct file *file,char *buf,size_t count, *                         loff_t *f_pos) *                         { *                             return copy_to_user(buf,buf_dev,count); *                             } *                             */static const struct file_operations _tmem_ctl_fops = {        .open = nonseekable_open,        .unlocked_ioctl = tmem_ioctl,        .owner = THIS_MODULE,#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,2,0)        .llseek = noop_llseek#else        .llseek = no_llseek#endif};static struct miscdevice _tmem_misc = {        .minor = MISC_DYNAMIC_MINOR,        .name = "tmemcontrol",        .nodename = "tmemcontrol",        .fops = &_tmem_ctl_fops};/*static do_event(char *input,char *output,int num) * { *        memcpy(output,input,num); *        }*/static int __init t_init(void){    int r;    TMEMINFO("hello,world\n");    r = misc_register(&_tmem_misc);    if(r)    {        TMEMERR("misc_register failed for control device");        return r;    }    mutex_init(&ioctl_mutex);    mutex_init(&count_mutex);    return 0;}static void __exit t_exit(void){    TMEMINFO("GOODBYE,MODULE\n");    if(misc_deregister(&_tmem_misc) < 0)    {         TMEMERR("misc_deregister failed for tmem control device");    }    mutex_destroy(&ioctl_mutex);    mutex_destroy(&count_mutex);}module_init(t_init);module_exit(t_exit);