Re: HT apparently not detected properly on 2.4.23

[Ethan Weinstein <lists@stinkfoot.org>]

William Lee Irwin III wrote:

> On Wed, Dec 03, 2003 at 01:46:38PM -0500, Ethan Weinstein wrote:
> 
>>With 2.4.22, my Supermicro X5DPL-iGM-O (E7501 chipset) with 2 
>>xeons@2.4ghz and hypertherading enabled shows 4 cpu's in 
>>/proc/cpuinfo|proc/interrupts, with:
>>CONFIG_ACPI=y
>>CONFIG_ACPI_HT_ONLY=y
>>The same config with 2.4.23 only shows 2 cpus, even with:
>>CONFIG_NR_CPUS=4
>>Also, I believe this has been reported before, but the system only seems 
>>to interrupt on CPU0 with either kernel, unless I apply a patch I found 
>>here:
>>http://www.hardrock.org/kernel/2.4.22/irqbalance-2.4.22-MRC.patch
>>or run the `irqbalance' program.. which I don't care to do.  This 
>>problem _seems_ to be isolated to the Supermicro, as HT does seem 
>>properly detected on several other SMP systems I have at work (compaq 
>>ML370/ML380) with 2.4.23
> 
> You probably have sparse physical APIC ID's.
> 
Ok, setting CONFIG_NR_CPUS=8 does indeed solve the HT issue, looks like 
it was the numbering scheme:

Dec  3 18:32:28 spicymeatball kernel: CPU 0 (0x0000) enabled
Dec  3 18:32:28 spicymeatball kernel: Processor #0 Pentium 4(tm) 
XEON(tm) APIC version 16
Dec  3 18:32:28 spicymeatball kernel: LAPIC (acpi_id[0x0001] id[0x6] 
enabled[1])
Dec  3 18:32:28 spicymeatball kernel: CPU 1 (0x0600) enabled
Dec  3 18:32:28 spicymeatball kernel: Processor #6 Pentium 4(tm) 
XEON(tm) APIC version 16
Dec  3 18:32:28 spicymeatball kernel: LAPIC (acpi_id[0x0002] id[0x1] 
enabled[1])
Dec  3 18:32:28 spicymeatball kernel: CPU 2 (0x0100) enabled
Dec  3 18:32:28 spicymeatball kernel: Processor #1 Pentium 4(tm) 
XEON(tm) APIC version 16
Dec  3 18:32:28 spicymeatball kernel: LAPIC (acpi_id[0x0003] id[0x7] 
enabled[1])
Dec  3 18:32:28 spicymeatball kernel: CPU 3 (0x0700) enabled
Dec  3 18:32:28 spicymeatball kernel: Processor #7 Pentium 4(tm) 
XEON(tm) APIC version 16

But we're still only interrupting on CPU0 with this kernel.


-Ethan