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* Using lswi/stswi inside the kernel
@ 2005-07-14 12:52 Frank van Maarseveen
  2005-07-14 13:24 ` Kumar Gala
  0 siblings, 1 reply; 3+ messages in thread
From: Frank van Maarseveen @ 2005-07-14 12:52 UTC (permalink / raw)
  To: linuxppc-dev

Are there any issues I should be aware of?

I think most SAVE_GPR* and REST_GPR* macros could be replaced by a
single lswi/stswi instruction.

-- 
Frank

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: Using lswi/stswi inside the kernel
  2005-07-14 12:52 Using lswi/stswi inside the kernel Frank van Maarseveen
@ 2005-07-14 13:24 ` Kumar Gala
  2005-07-14 20:48   ` Segher Boessenkool
  0 siblings, 1 reply; 3+ messages in thread
From: Kumar Gala @ 2005-07-14 13:24 UTC (permalink / raw)
  To: Frank van Maarseveen; +Cc: linuxppc-dev

Yes, not all PowerPC implementations actually implement this  
instructions.  Also, on a number of them there is no performance  
improvement when using the instructions.

- kumar

On Jul 14, 2005, at 7:52 AM, Frank van Maarseveen wrote:

> Are there any issues I should be aware of?
>
> I think most SAVE_GPR* and REST_GPR* macros could be replaced by a
> single lswi/stswi instruction.
>
> -- 
> Frank
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev@ozlabs•org
> https://ozlabs.org/mailman/listinfo/linuxppc-dev
>

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: Using lswi/stswi inside the kernel
  2005-07-14 13:24 ` Kumar Gala
@ 2005-07-14 20:48   ` Segher Boessenkool
  0 siblings, 0 replies; 3+ messages in thread
From: Segher Boessenkool @ 2005-07-14 20:48 UTC (permalink / raw)
  To: Kumar Gala; +Cc: linuxppc-dev

> Yes, not all PowerPC implementations actually implement this 
> instructions.  Also, on a number of them there is no performance 
> improvement when using the instructions.

Read: severe performance degradation ;-)


Segher

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2005-07-14 20:47 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2005-07-14 12:52 Using lswi/stswi inside the kernel Frank van Maarseveen
2005-07-14 13:24 ` Kumar Gala
2005-07-14 20:48   ` Segher Boessenkool

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