Logical CPUs cannot be disabled via W3520

[John Baldwin]

On Sunday 21 March 2010 6:40:17 pm Garrett Cooper wrote:
>     Someone on the forums [1] noticed that machdep.hlt_logical_cpus
> was unavailable on their system, and I did some poking around and
> noticed that it was as well. Should SMT logical CPUs be disable(-able)
> via machdep.hlt_logical_cpus as well or is it just classic HTT based
> chips?

I suspect that it should work for SMT as well.

> Thanks,
> -Garrett
> 
> $ sysctl machdep.
> machdep.acpi_timer_freq: 3579545
> machdep.enable_panic_key: 0
> machdep.adjkerntz: 25200
> machdep.wall_cmos_clock: 1
> machdep.disable_rtc_set: 0
> machdep.acpi_root: 1029056
> machdep.disable_mtrrs: 0
> machdep.idle: acpi
> machdep.idle_available: spin, mwait, mwait_hlt, hlt, acpi,
> machdep.hlt_cpus: 0
> machdep.prot_fault_translation: 0
> machdep.panic_on_nmi: 1
> machdep.kdb_on_nmi: 1
> machdep.tsc_freq: 2694121808
> machdep.i8254_freq: 1193182
> $ sysctl hw.machine hw.model
> hw.machine: amd64
> hw.model: Intel(R) Xeon(R) CPU           W3520  @ 2.67GHz
> 
> dmesg snippet:
> 
> CPU: Intel(R) Xeon(R) CPU           W3520  @ 2.67GHz (2694.12-MHz K8-class 
CPU)
>   Origin = "GenuineIntel"  Id = 0x106a5  Family = 6  Model = 1a  Stepping = 
5
>   
Features=0xbfebfbff<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,HTT,TM,PBE>
>   
Features2=0x9ce3bd<SSE3,DTES64,MON,DS_CPL,VMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,DCA,SSE4.1,SSE4.2,POPCNT>
>   AMD Features=0x28100800<SYSCALL,NX,RDTSCP,LM>
>   AMD Features2=0x1<LAHF>
>   TSC: P-state invariant
> real memory  = 12884901888 (12288 MB)
> avail memory = 12379992064 (11806 MB)
> ACPI APIC Table: <091109 APIC2100>
> FreeBSD/SMP: Multiprocessor System Detected: 8 CPUs
> FreeBSD/SMP: 1 package(s) x 4 core(s) x 2 SMT threads
>  cpu0 (BSP): APIC ID:  0
>  cpu1 (AP): APIC ID:  1
>  cpu2 (AP): APIC ID:  2
>  cpu3 (AP): APIC ID:  3
>  cpu4 (AP): APIC ID:  4
>  cpu5 (AP): APIC ID:  5
>  cpu6 (AP): APIC ID:  6
>  cpu7 (AP): APIC ID:  7
> 
> [1] http://forums.freebsd.org/showthread.php?t=12527
> 

-- 
John Baldwin