Re: [PATCH] x86_64: Limit the number of processor bootup messages

[Ingo Molnar <mingo@elte.hu>]

* Mike Travis <travis@sgi.com> wrote:

>
>
> Andi Kleen wrote:
>> Mike Travis wrote:
>>>
>>> This set of patches limits the number of repetitious messages which  
>>> contain
>>> no additional information.  Much of this information is obtainable  
>>> from the
>>> /proc and /sysfs.   Most of the messages are also sent to the kernel log
>>> buffer as KERN_DEBUG messages so it can be used to examine more  
>>> closely any
>>> details specific to a processor.
>>
>> What would be good is to put the information from the booting CPUs
>> into some buffer and print it visibly if there's a timeout detected on  
>> the BP.
>
> What do you think of this idea....  Add a "mark kernel log buffer" 
> function, and then if any KERN_NOTE or above happens, it sends the 
> marked info from the kernel log buffer to the console before the 
> current message.  Set the marker to '0' to clear.

That's _way_ too complex really, for little benefit. (If there's a boot 
hang people will re-try anyway (and this time with a serial console 
attached or so), and they can add various boot options to increase 
verbosity - depending in which phase the bootup hung.)

So please go with the simple solution i suggested days ago: print stuff 
on the boot CPU but after that only a single line per AP CPU.

	Ingo