Re: Linux 2.4.26-rc1 (cmpxchg vs 80386 build)

[Arkadiusz Miskiewicz <arekm-k0Z414SquRyhPH1hqNUYSQ@public.gmane.org>]

Dnia Monday 29 of March 2004 09:01, Denis Vlasenko napisał:

> > > 4. re-implement locks for the 80386 case.
> >
> > I like this one, but a simpler way : don't support SMP in this case, so
> > that we won't have to play with locks. This would lead to something like
> > this :
>
> Yes, SMP makes sense only on 486+
I want to run i386 compiled kernel on 486+ smp machines

> > #ifndef CONFIG_X86_CMPXCHG
> > #ifndef CONFIG_SMP
> > #define cmpxchg(lock,old,new) ((*lock == old) ? ((*lock = new), old) :
> > (*lock)) #else
> > #define cmpxchg(lock,old,new) This_System_Is_Not_Supported
> > #endif
> > #endif
and this won't allow me to do that

> > This code (if valid) might be added to asm-i386/system.h so that we don't
> > touch ACPI code.
> >
> > Any comments ?
so I preffer 3. invoke cmpxchg from acpi even for 80386 build + cpuid/other 
check to not run this code on 386.

-- 
Arkadiusz Miśkiewicz     CS at FoE, Wroclaw University of Technology
arekm.pld-linux.org, 1024/3DB19BBD, JID: arekm.jabber.org, PLD/Linux


-------------------------------------------------------
This SF.Net email is sponsored by: IBM Linux Tutorials
Free Linux tutorial presented by Daniel Robbins, President and CEO of
GenToo technologies. Learn everything from fundamentals to system
administration.http://ads.osdn.com/?ad_id\x1470&alloc_id638&op=click