Re: [PATCH 1/3] mce: Add a msg string to the MCE tracepoint

[Mauro Carvalho Chehab]

Em 01-03-2012 08:29, Borislav Petkov escreveu:
> On Wed, Feb 29, 2012 at 05:33:51PM +0000, Luck, Tony wrote:
>>> IOW, we want to assume that cores 0, 1, 2 ... k-1 are on node 0; k, k+1
>>> ... 2k-1 belong to node 1, etc., where k is the number of cores on a
>>> socket and thus we have a regular core enumeration on the box.
>>
>> Sounds dubious:
>>
>> Booting Node   0, Processors  #1 #2 #3 #4 #5 #6 #7 Ok.
>> Booting Node   1, Processors  #8 #9 #10 #11 #12 #13 #14 #15 Ok.
>> Booting Node   0, Processors  #16 #17 #18 #19 #20 #21 #22 #23 Ok.
>> Booting Node   1, Processors  #24 #25 #26 #27 #28 #29 #30 #31
>> Brought up 32 CPUs
>>
>> Now those are logical cpu numbers, and we brought up the first HT
>> thread on each core first, and then came around for a 2nd pass
>> bringing up the other HT thread.  This order is determined by
>> how the BIOS lists the cpus (and in this case it seems to be
>> doing so according to recommendations) - so here our core numbers
>> will match what you said. But the BIOS could do something
>> strange and list logical cpus alternating between sockets. In
>> which case cores 0, 2, 4, 6 ... would be on node 0, and cores
>> 1, 3, 5, 7, ... on node 1.
> 
> Ok, the example above actually confirms my fear that you won't be always
> able to map back to a physical socket from the CPU number. So, we'll
> need the ->socketid field which is the physical processor ID we get from
> CPUID leafs.
> 
> Then, mapping back the socketid to the silkscreen labels on the boards
> should be easy because on the boxes I have here, they go like this: P0,
> P1, ..., where P0 is the socket containing the BSP, P1 is the second
> socket etc. I'm guessing this is similar on Intel boards...?

The mapping from socket id to silkscreen label is motherboard-dependent.
I did some tests with a few different machines:

[root@dell-pe1950-05 ~]# dmidecode | grep -i "Processor Information" -A10
Processor Information
	Socket Designation: CPU1
	Type: Central Processor
	Family: Xeon
	Manufacturer: Intel
	ID: F6 06 00 00 FF FB EB BF
	Signature: Type 0, Family 6, Model 15, Stepping 6
	Flags:
		FPU (Floating-point unit on-chip)
		VME (Virtual mode extension)
		DE (Debugging extension)
--
Processor Information
	Socket Designation: CPU2
	Type: Central Processor
	Family: Xeon
	Manufacturer: Intel
	ID: F6 06 00 00 FF FB EB BF
	Signature: Type 0, Family 6, Model 15, Stepping 6
	Flags:
		FPU (Floating-point unit on-chip)
		VME (Virtual mode extension)
		DE (Debugging extension)

[root@hp-dl580g5-01 ~]# dmidecode | grep -i "Processor Information" -A10
Processor Information
	Socket Designation: Proc 1
	Type: Central Processor
	Family: Xeon MP
	Manufacturer: Intel
	ID: FB 06 00 00 FF FB EB BF
	Signature: Type 0, Family 6, Model 15, Stepping 11
	Flags:
		FPU (Floating-point unit on-chip)
		VME (Virtual mode extension)
		DE (Debugging extension)
--
Processor Information
	Socket Designation: Proc 2
	Type: Central Processor
	Family: Xeon MP
	Manufacturer: Intel
	ID: FB 06 00 00 FF FB EB BF
	Signature: Type 0, Family 6, Model 15, Stepping 11
	Flags:
		FPU (Floating-point unit on-chip)
		VME (Virtual mode extension)
		DE (Debugging extension)
--
Processor Information
	Socket Designation: Proc 3
	Type: Central Processor
	Family: Xeon MP
	Manufacturer: Intel
	ID: FB 06 00 00 FF FB EB BF
	Signature: Type 0, Family 6, Model 15, Stepping 11
	Flags:
		FPU (Floating-point unit on-chip)
		VME (Virtual mode extension)
		DE (Debugging extension)
--
Processor Information
	Socket Designation: Proc 4
	Type: Central Processor
	Family: Xeon MP
	Manufacturer: Intel
	ID: FB 06 00 00 FF FB EB BF
	Signature: Type 0, Family 6, Model 15, Stepping 11
	Flags:
		FPU (Floating-point unit on-chip)
		VME (Virtual mode extension)
		DE (Debugging extension)

dmidecode | grep -i "Processor Information" -A10
Processor Information
	Socket Designation: CPU 1
	Type: Central Processor
	Family: Pentium M
	Manufacturer: Intel            
	ID: A4 06 01 00 FF FB EB BF
	Signature: Type 0, Family 6, Model 26, Stepping 4
	Flags:
		FPU (Floating-point unit on-chip)
		VME (Virtual mode extension)
		DE (Debugging extension)
--
Processor Information
	Socket Designation: CPU 2
	Type: Central Processor
	Family: Pentium M
	Manufacturer: Intel            
	ID: A4 06 01 00 FF FB EB BF
	Signature: Type 0, Family 6, Model 26, Stepping 4
	Flags:
		FPU (Floating-point unit on-chip)
		VME (Virtual mode extension)
		DE (Debugging extension)

[root@hp-bl260cg5-01 ~]# dmidecode | grep "Processor Information" -A10
Processor Information
	Socket Designation: Proc 1
	Type: Central Processor
	Family: Xeon
	Manufacturer: Intel
	ID: 76 06 01 00 FF FB EB BF
	Signature: Type 0, Family 6, Model 23, Stepping 6
	Flags:
		FPU (Floating-point unit on-chip)
		VME (Virtual mode extension)
		DE (Debugging extension)
--
Processor Information
	Socket Designation: Proc 2
	Type: Central Processor
	Family: Xeon
	Manufacturer: Intel
	ID: 00 00 00 00 00 00 00 00
	Signature: Type 0, Family 0, Model 0, Stepping 0
	Flags: None
	Version: Not Specified
	Voltage: 1.1 V
	External Clock: 200 MHz

On all the above, the socket label starts on 1, but I bet we'll find cases
where it start from 0.


Regards,
Mauro
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