Re: HT not active

[Arjan van de Ven <arjan@linux.intel.com>]

On Mon, 2006-08-14 at 13:38 +0200, Jan Engelhardt wrote:
> Hello list,
> 
> 
> 
> I cannot get HT to be used on some machine:
> 
> w04a# cat /proc/cpuinfo 
> processor       : 0
> vendor_id       : GenuineIntel
> cpu family      : 15
> model           : 0
> model name      : Intel(R) Pentium(R) 4 CPU 1700MHz
> stepping        : 10
> cpu MHz         : 1694.890
> cache size      : 256 KB
> fdiv_bug        : no
> hlt_bug         : no
> f00f_bug        : no
> coma_bug        : no
> fpu             : yes
> fpu_exception   : yes
> cpuid level     : 2
> wp              : yes
> flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca 
> cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm up
> bogomips        : 3393.46
> 
> 'ht' indicates:
> #define X86_FEATURE_HT          (0*32+28) /* Hyper-Threading */                 


the "ht" flag does not mean what you think it means.....
it does NOT mean "I can use hyperthreading on this machine"; it
basically means "the ht cpuid commands work", so that linux can find the
nr of siblings, which can be..... 1