Re: Using %cr2 to reference "current"

Martin Dalecki
2001-11-11T12:24:50Z

Alan Cox wrote:
>
> > With the following options enabled we get:
> > -freg-struct-return -mrtd -mregparm=3
> >
> > text data bss dec hex filename
> > 1302372 260804 288080 1851256 1c3f78 vmlinux
> >
> > Quite significant difference if you ask me!!!
>
> 30K is nice have but still a scratch on the surface compared with 500K 8)
>
> > in a saving of about 2.3% in code size. This may not sound grat in
> > relative
> > numbers, but for a compiler designer this would already sound hilarious
> > and in
> > absolute numbers it's: 29760 bytes. Not withstanding the speed
> > improvement...
>
> The obvious question is - have you tried running the kernel built like that
> with any asm fixups needed ?

I have now a nice kernel at home, compiled with -mredparm=3 up
and going. Full interactive session, full kernel compiles working,
X11 whatsup. Everything seems fine so far.

However I still have to build a RPM-feature grade kernel and test it.
Further the precise benchmarking will take some time as well.
I think that I will in esp. use the byte benchmark, since it is
quite "kernel intensive" at some parts. Patch will follow on
monday (if nothing comes in between...).