From: Ted Ts'o <tytso@mit.edu>
Subject: Re: [PATCH 2/9] ext4: Use pr_fmt and pr_<level>
Date: Mon, 19 Mar 2012 21:04:01 -0400
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Cc: David Miller <davem@davemloft.net>, anca.emanuel@gmail.com,
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To: Joe Perches <joe@perches.com>
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On Mon, Mar 19, 2012 at 11:46:13AM -0700, Joe Perches wrote:
> On Mon, 2012-03-19 at 14:31 -0400, Ted Ts'o wrote:
> > On Mon, Mar 19, 2012 at 02:14:02PM -0400, David Miller wrote:
> > I've *already* gone far beyond the pr_fmt standardization, with the
> > ext4_msg() and ext4_error() system
> 
> Please note the defects that were recently corrected there
> which occurred because of a lack of standardization both
> in prefix and termination style.

For debugging printk's that are #ifdef'ed for anyone other than ext4
developers and can't be enabled via CONFIG_*.  Yawn.

> Any logging system, with or without an external notification
> mechanism, will be painful.  pr_<foo> is at least a small
> start.  I'd like to see a notification mechanism, perhaps ala
> netlink/ethtool to extend pr_<foo> or another call.  A lot of
> these printk/pr_<level> uses really could generate notifications.

Yes, but we can't do structured notifications with the current
pr_<foo>.  So why change literally tens of thousands of callsites when
in order to really realize the full promise of structured
notifications, we'll have to change them *again*?

	       	     	     	    	 - Ted