Re: 2.4.22 SMP kernel build for hyper threading P4

From: Job 317
Date: Sat Nov 15 2003 - 13:45:35 EST


On 15-Nov-2003 17:30:11 +0100, you wrote:
> > I have a new P4 Hyperthreading PC that I have installed RedHat9 on.
I am
>
> I presume you realize that anyone who understands HT has mostly scorn
for it.

I had no idea but it is still a huge improvement over my HP 755MHz
Celleron that I am replacing ;) Might I as why so and am I wasting my
time when a non-SMP kernel builds and works just fine?

>
> > api, etc.) but when I build my new 2.4.22 kernel with CONFIG_SMP=y
set
> > then reboot, I am seeing only one processor in /proc/cpuinfo. When
I
> > boot with my stock RH9 2.4.20-20.9smp kernel I see two virtual
> > processors show up in /proc/cpuinfo.
>
> I'm guessing you don't have acpi enabled.

Hmm... Let's have a look. I started by loading the
kernel-2.4.20-i686-smp.config file that came with the RH9 distro into
xconfig. I just turned on ntfs and a couple of other things and saved.
The comparision is strange. My new config file has:

# CONFIG_ACPI is not set

however the RH9 config file has:

# CONFIG_ACPI is not set
# CONFIG_ACPI_DEBUG is not set
# CONFIG_HOTPLUG_PCI_ACPI is not set
# CONFIG_ACPI_HT_ONLY is not s
CONFIG_ACPI_BUSMGR=m
CONFIG_ACPI_SYS=m
CONFIG_ACPI_CPU=m
CONFIG_ACPI_BUTTON=m
CONFIG_ACPI_AC=m
CONFIG_ACPI_EC=m
CONFIG_ACPI_CMBATT=m
CONFIG_ACPI_THERMAL=m
CONFIG_ACPI_RELAXED_AML=y

So should I have all this or no?

>
> > I've even build a 2.4.22 kernel with the config-2.4.20-20.9smp
> > configuration that came with RH9.
>
> RH doesn't ship kernel.org sources, of course. hence the -20.

Rgr. I got this.

>
> > I build with the straightforward 'make dep clean bzImage modules
> > modules_install' command. Is this correct?
>
> sure. obviously, you need to verify that you're booting the kernel
> that you just made, etc.

It does boot and everything else "seems" fine. Just that I still only
get one virtual CPU showing up in /proc/cpuinfo.

>
> > Am I missing a step to build a smp kernel for hyper threading?
>
> HT is a non-feature; it requires nothing from the kernel. I'm
> guessing your problem is bios or acpi.
>

I still don't understand. So am I wasting my time with HT?

Thanks,

Job