回复： pow function in kernel space

[张晗]

Hi:
  
 I am doing a research on D2TCP(http://dl.acm.org/citation.cfm?id=2342388), I just want to implement it into the linux kernel. When calculating the penalty function, it is p = a^d, where 0< a < 1 and  0< d < 1. Since the kernel only offers integer,   so in my code, so I let a multiply 2^10. But I have no idea of calculating a^d when 0< d < 1. May be I want a  approximate algorithm or other methods. Can you help me ?
 thanks~
  
  
  
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祝好，
 
张晗
 
 
 
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HanZhang
 
School of Computer Science
Tsinghua University, Beijing, 100084, P.R.CHINA
 
Mobile:  +86 156-526-59782
E-mail:   zhanghan at csnet1.cs.tsinghua.edu.cn

  
  

 

 ------------------ 原始邮件 ------------------
  发件人: "Andrey Zonov";<zont at FreeBSD.org>;
 发送时间: 2014年6月20日(星期五) 凌晨3:04
 收件人: "张晗"<zganghanhan at foxmail.com>; "freebsd-net"<freebsd-net at freebsd.org>; 
 
 主题: Re: pow function in kernel space

 

There is no floating point types in kernel, so there is no pow() in kernel.

On 6/19/14, 5:40 AM, 张晗 wrote:
> how can I implement, in an efficient, way the pow() function in kernel space ?  Is there any function I can use o r how I can evaluate pow function in kernel model?
>   
>  Thanks!
>  
>  
>   ------------------
>   
> 祝好，
>  
> 张晗
>  
>  
>  
> ---------- 
>  
> HanZhang
>  


-- 
Andrey Zonov