Multi-Core Support in Minix 3.3.0

[Ramachandra Pai]

Hello All,

I am newbie at Minix and I just installed Minix on Qemu. I noticed that when i do a "/proc/cpuinfo" only one core is shown while in my qemu command line I specified 4 cores to be allocated to the guest OS.

I did a bit a digging around and i found that earlier versions of Minix did not support Multi-Core. Does the same hold true with Minix 3.3.0?

       

[Antoine LECA]

On 25/02/2015 17:01Z, Ramachandra Pai wrote:
> I am newbie at Minix and I just installed Minix on Qemu. I noticed that
> when i do a "/proc/cpuinfo" only one core is shown while in my qemu command
> line I specified 4 cores to be allocated to the guest OS.

By default MINIX3 is built as single-processor system. Have a look at
http://wiki.minix3.org/doku.php?id=developersguide:rebuildingsystem#building_and_booting_smp
for more details about SMP. Beware though: this is not a often-tested
configuration, you are almost certain to encounter pitfalls.

If you discover interesting things, please report them here, I am sure
this will benefit the whole community.


Antoine

[Ramachandra Pai]

Thank you Antoine for the quick reply.

I tried the steps mentioned in the link(http://wiki.minix3.org/doku.php?id=developersguide:rebuildingsystem#building_and_booting_smp) ,

1. I downloaded the Minix kernel source code in /usr/src

2. I set the flags CONFIG_SMP=y and CONFIG_MAX_CPUS=4 and rebuilt the kenel with "make build"

3. Rebooted the qemu and ran the latest kenel in the boot menu. 

The system rebooted as usual but this time i allocated 4 core through qemu and logged in as root. i checked the number of cpus through "cat /proc/cpuinfo" and it still shows only 1 core and not 4. I followed all the steps above twice to make sure i didn't do anything wrong.

Is there any way to make sure that the kenel has been built in SMP mode? If the kernel has been built in the SMP mode what else can go wrong here?

Let me know if i need to give any more information regarding my setup.

[Ramachandra Pai]

Hi all,

I was able to run Minix with multi-core support for 2 cores on qemu but when i build the system for 4 cores and run i get the following error from qemu. Does anybody know anything about this?  

KVM internal error. Suberror: 1

emulation failure

EAX=00000000 EBX=00000000 ECX=00000006 EDX=00000000

ESI=0806403c EDI=08064008 EBP=efffff84 ESP=efffff80

EIP=0805c8c3 EFL=00000213 [----A-C] CPL=3 II=0 A20=1 SMM=0 HLT=0

ES =0023 00000000 ffffffff 00c0f300 DPL=3 DS   [-WA]

CS =001b 00000000 ffffffff 00c0fb00 DPL=3 CS32 [-RA]

SS =0023 00000000 ffffffff 00c0f300 DPL=3 DS   [-WA]

DS =0023 00000000 ffffffff 00c0f300 DPL=3 DS   [-WA]

FS =0023 00000000 ffffffff 00c0f300 DPL=3 DS   [-WA]

GS =0023 00000000 ffffffff 00c0f300 DPL=3 DS   [-WA]

LDT=0028 00000000 ffffffff 00c08200 DPL=0 LDT

TR =0030 f04650c0 00000067 00408b00 DPL=0 TSS32-busy

GDT=     f0465080 0000003f

IDT=     8ff8f044 00006ff8

CR0=8001003b CR2=00000000 CR3=0046d000 CR4=00000690

DR0=00000000 DR1=00000000 DR2=00000000 DR3=00000000 

DR6=ffff0ff0 DR7=00000400

EFER=0000000000000000

Code=90 55 89 e5 53 b8 00 00 00 00 bb 00 00 00 00 b9 06 00 00 00 <cd> 21 8b 4d 08 89 19 5b 5d c3 66 90 90 8b 44 24 04 cd 20 c3 66 90 66 90 66 90 66 90 90 55

Regards,

Ramachandra Pai

[Vanessa Vargas]

Hi Ramachandra,

I would like to know if you had solved your problem.

I am trying to boot in smp mode a machine with intel i-7  with 4 cores but I have the same original problem that you had.

I tried the same steps that you mentioned  an is stated in in the link(http://wiki.minix3.org/doku.php?id=developersguide:rebuildingsystem#building_and_booting_smp) ,

1. I downloaded the Minix kernel source code in /usr/src

2. I set the flags CONFIG_SMP=y and CONFIG_MAX_CPUS=4 and rebuilt the kenel with "make build"

3. Rebooted the machine and ran the latest kernel in the boot menu. 

The system rebooted and I logged in as root. I checked the number of cpus through "cat /proc/cpuinfo" and it still shows only 1 core and not 4.

Also in other discussion link I found that

What I should have in the boot.cfg is a line like

 menu=Start MINIX 3:load_mods /boot/minix_default/mod*;

multiboot /boot/minix_default/kernel rootdevname=c0d0p3s0 no_apic=0 acpi=1

But when I added no_apic=0 acpi=1, the system could not boot and it reboots automatically.

If you have any idea, please let me know.

Regards,

Vanessa

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