From: Jiri Slaby <jslaby@suse.cz>
Subject: Re: [PATCH 2/9] ext4: Use pr_fmt and pr_<level>
Date: Tue, 20 Mar 2012 09:47:03 +0100
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To: David Miller <davem@davemloft.net>
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On 03/20/2012 08:10 AM, David Miller wrote:
> From: Valdis.Kletnieks@vt.edu
> Date: Tue, 20 Mar 2012 01:46:06 -0400
> 
>> OK. Say I'm a scraper.  How do I distinguish between:
>>
>> pr_info("foo");
>> printk(KERN_INFO "foo");
>>
>> Oh my. seems that both result in exactly the same thing ending up in the
>> dmesg buffer
> 
> No it doesn't result in the same output, read the definitions again.
> 
> pr_info can be influenced by pr_fmt, plain printk cannot

Ok, but how exactly does one select per-subsystem messages relying only
on pr_fmt?

Joe writes: "notify a particular set of per subsystem messages that
pr_<level> could easily provide"

Maybe the concept is not explained well enough that we do not follow?

thanks,
-- 
js
suse labs