2GB address space limit on 32-bit PowerPC Macintosh

Eugene Surovegin ebs at ebshome.net
Tue May 17 02:22:04 EST 2005

On Mon, May 16, 2005 at 06:11:03PM +0200, Wolfgang Denk wrote:
> In message <1116255938.5095.133.camel at gaston> you wrote:
> >
> > I suppose it would add about ... 1 instruction :) Which is probably
> > barely measurable compared to the cost of the cache misses of getting to
> > the page table entires...
> That would be just another "just 1 instruction"  modifircation  to  a
> time  critical path in a kernel which already now is so slow compared
> against an old 2.4 kernel that I'm really surprised to  nobody  seems
> to care.

Well, this just one instruction is needed to make code correct anyway, 
because currently head_8xx.S, head_4xx.S, head_44x.s just hardcode 
0x80000000 TASK_SIZE assumption, and you cannot change TASK_SIZE on 
all this hardware.


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