RE: 2.6.12-rc5 is broken in nvidia Ck804 Opteron MB/with dual cor e dual way

From: YhLu
Date: Thu Jun 02 2005 - 15:48:41 EST


cpuid(1, &eax, &ebx, &ecx, &edx);
smp_num_siblings = (ebx & 0xff0000) >> 16;

For amd dual core, smp_num_siblings is set to 1, and it mean has two cores.

seq_printf(m, "siblings\t: %d\n",
c->x86_num_cores * smp_num_siblings);

for Intel it would be
c->x86_num_cores is 2 and smp_num_siblings is 2 too....
so every core will be HT....


Function 0000_0001[EBX]
EBX[23:16] Logical Processor Count. If CPUID Fn[8000_0001, 0000_0001][EDX:
HTT, ECX:
CMPLegacy] = 11b, then this field indicates the number of CPU cores in the
processor.
Otherwise, this field is reserved.

what is intel value about cpuid(1) ebx [23:16], when the CPU is dual core,
but HT is disabled.
1?

YH

> -----Original Message-----
> From: Ashok Raj [mailto:ashok.raj@xxxxxxxxx]
> Sent: Thursday, June 02, 2005 12:07 PM
> To: YhLu
> Cc: Andi Kleen; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: 2.6.12-rc5 is broken in nvidia Ck804 Opteron
> MB/with dual cor e dual way
>
> On Thu, Jun 02, 2005 at 11:56:25AM -0700, YhLu wrote:
> >
> > Really?, smp_num_siblings is global variable and
> initially is set 1.
> >
> > YH
> >
> But detect_ht() can override it.. thats just the start value.
>
> try cscope :-)
>
> Cheers,
> ashok
>
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