Re: [PATCH] String conversions for memory policy

[Andi Kleen <ak@suse.de>]

On Thu, Aug 04, 2005 at 07:11:36AM -0700, Christoph Lameter wrote:
> On Wed, 3 Aug 2005, Andi Kleen wrote:
> 
> > I really hate this whole /proc/<pid>/numa_policy thing. /proc/<pid>/maps
> > was imho always a desaster (hard to parse, slow etc.). Also external
> > access of NUMA policies has interesting locking issues. I intentionally
> > didn't add something like that when I designed the original
> > NUMA API. Please don't add it.
> 
> You designed a NUMA API to control a process memory access patterns 
> without the ability to view or modify the policies in use?

Processes internally can get the information if they want.
Externally I didn't expose it intentionally to avoid locking problems

> The locking issues for the policy information in the task_struct could be 
> solved by having a thread execute a function that either sets or gets the 
> memory policy. The vma policies already have a locking mechanism.

But why? It all only adds complexity. Keep it simple please.

>  
> This piece here only does conversion to a string representation so it 
> should not be affected by locking issues. Processes need to do proper 
> locking when using the conversion functions.

It's useless.

-Andi