Re: [PATCH 0/6] loglevel=pci:8,acpi:8,apic=8 support v6

Jason Baron
2008-09-18T15:52:12Z

On Thu, Sep 18, 2008 at 08:36:43AM -0700, H. Peter Anvin wrote:
> Ingo Molnar wrote:
>>
>> which is what we really want. If a bootup fails, the user has to repeat
>> the bootup at least once with a verbosity level increased and with
>> (hopefully) some sort of log capture facility attached.
>>
>> So the point would be, if the user specified loglevel=all, we would get
>> really comprehensive, one-stop-shop output.
>>
>
> That is true if the bootup fails, but it's fairly common that we get the
> machine up (at least to the point when we can dmesg), but the user wants
> to report a problem. For that case, it's very nice if the dmesg log
> contains as much information as possible.
>
> So I don't think it's clear that pre-filtering is what we want, at all.
>
> -hpa
>

hi,

if we take this argument to its extreme, then we end up spending all of
our time verifying that the kernel is working correctly and no time
actually doing work. I think 'printk_ratelimit' captures this. Thus, the line
has to be drawn somewhere. If you want the messages in 'dmesg' use,
printk(KERN_DEBUG), and 'grep'. For the rest, I propose pre-filtering, which is
what 'dynamic debug' uses.

thanks,

-Jason