Re: [patch v2] x86: reduce srat verbosity in the kernel log

[Mike Travis <travis@sgi.com>]

David Rientjes wrote:
> On Tue, 10 Nov 2009, Ingo Molnar wrote:
> 
>> I'm waiting for Mike to test them (and other patches) and send a new 
>> series out with bits to pick up.
>>
> 
> Mike posted his series today without including my patch, so I've replied 
> to it.

Sorry, I wasn't aware I should have.
> 
>> But i really dont like such type of buffering - in the past they tended 
>> to be problematic.
> 
> I'm not sure that I'd call it buffering when iterating through all apic 
> id's and setting appropriate bits in a bitmap when they map to a node id.  
> It's apparently not been problematic either on my machines, Mike's 
> machines, or his merge with ACPI 4.0 code.  I think the code is pretty 
> straight forward.
> 
>> Why print this info at all in the default bootup?  
>> It's not needed on a correctly functioning system.
>>
> 
> We have no other export of the apic id to to node mappings in the kernel.  
> We already show each pxm's address range, each node's address range, and 
> the pxm to node map.  The only other way to map apic ids to nodes is by 
> looking for the lines "CPU 0/0 -> Node 0," which I believe are being 
> removed.

The bootup messages in my patch 1/7 list nodes and their processors as each
boots.  And this is easily found under /sysfs.

Also, I think in general that all the apic messages, unless they represent
"system boot progress" should be displayed only when asked for, like with
apic=debug or verbose?   Something more like:

BIOS-provided physical RAM map processed.
EFI: memory allocated.
SRAT: table interpreted.
Bootmem setups complete.
ACPI: APIC's enabled.
PM: Registered all nosave memory.

Removing the above tables remove about 3400 lines of console output on a 1k
thread machine.  There are 20,000+ lines of output before you get to the
login prompt (even with the removal of cpu bootup messages).

But you are right, the apic info should be available via /sysfs or /procfs.

The next BIG output is from devices.  Listing all the pci busses available
is an overkill as that info is also readily available when the system is
running.