Re: cannot compile sched_ule without options SMP

From: Jung-uk Kim <jkim_at_FreeBSD.org>
Date: Fri, 1 May 2009 16:10:40 -0400
On Thursday 30 April 2009 11:04 pm, pluknet wrote:
> 2009/5/1 pluknet <pluknet_at_gmail.com>:
> > 2009/5/1 Jeff Roberson <jroberson_at_jroberson.net>:
> >> On Thu, 30 Apr 2009, pluknet wrote:
> >>> 2009/4/30 Jeff Roberson <jroberson_at_jroberson.net>:
> >>>> On SMP machines you should now see output like this:
> >>>> FreeBSD/SMP: Multiprocessor System Detected: 8 CPUs
> >>>> FreeBSD/SMP: 1 package(s) x 4 core(s) x 2 SMT threads
> >>>>
> >>>> If you detect any irregularities with kern.sched.topology_spec
> >>>> or this dmesg
> >>>> line please report them.
> >>>
> >>> Hi, Jeff.
> >>>
> >>> I have such mismatch. This is an Intel E7200.
> >>>
> >>> FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs
> >>> FreeBSD/SMP: 1 package(s) x 1 core(s) x 2 HTT threads
> >>> cpu0 (BSP): APIC ID:  0
> >>> cpu1 (AP/HT): APIC ID:  1
> >>>
> >>> So it should be instead: 1 package(s) x 2 core(s)
> >>> cpu0 (BSP): APIC ID:  0
> >>> cpu1 (AP): APIC ID:  1
> >>
> >> Can you please repeat the following steps as I have done here:
> >
> > (kgdb) p/x cpu_high
> > $1 = 0x2
> > (kgdb) p/x cpu_cores
> > $2 = 0x1
> > (kgdb) p/x cpu_logical
> > $3 = 0x2
> > (kgdb) p/x cpu_feature
> > $4 = 0xbfebfbff
> > (kgdb) p/x logical_cpus
> > $5 = 0x2
> > (kgdb) p/x hyperthreading_cpus
> > $6 = 0x2
>
> Follow up myself:
>
> What is embarrassing me is HTT feature enabled. May the reason be
> in a buggy CPUID ?

No, the flag does not mean it supports Hyperthreading.  It means more 
than one logical core is supported (multi-threading) although the 
name didn't change for historical reason. ;-)

Can you try the attached patch?

Thanks!

Jung-uk Kim

Received on Fri May 01 2009 - 18:10:55 UTC

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