[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20080616181920.GA30284@redhat.com>
Date: Mon, 16 Jun 2008 14:19:21 -0400
From: "'Jason Baron'" <jbaron@...hat.com>
To: Takashi Nishiie <t-nishiie@...css.fujitsu.com>
Cc: akpm@...ux-foundation.org, linux-kernel@...r.kernel.org,
joe@...ches.com, greg@...ah.com, nick@...k-andrew.net,
randy.dunlap@...cle.com, mathieu.desnoyers@...ymtl.ca
Subject: Re: [PATCH 0/8] dynamic debug
On Mon, Jun 16, 2008 at 11:26:12AM +0900, Takashi Nishiie wrote:
> Jason Baron wrote:
> >Each kernel sub-system seems to have its own way of dealing with
> >debugging statements. Some of these methods include 'dprintk',
> >'pr_debug', 'dev_debug', 'DEBUGP'. There are also a myriad of
> >ways of enabling these statements.
>
> I propose to replace 'Pr_debug', 'Dev_debug', and 'DEBUGP' with
> kernel markers. SystemTap is used for the output of the log.
>
> I propose to make it to the function to output only specified
> kernel markers as a log and the function in a word like LTTng of
> a simple version by using the framework and kernel markers of
> ftrace if the log is output by using debugfs.
>
> Thank you,
>
perhaps markers could be used to replace 'pr_debug', 'dev_debug', and 'DEBUGP'
but i have yet to see patches for that...
In a number of ways, these dynamic debug patches differ from markers:
-Markers have a pre-defined format string and arguments list, whereas debug
statements have a 'printk' format
-these patches are built around per-module debugging, which is largely implicit
whereas markers explicitly define sets of related markers.
-these patches allow 'flags' and levels to be set per-module, markers do not
have this concept.
-these patches are tied into a procfs control file, whereas markers are
controlled by kernel modules which register handlers.
These two patchsets are really addressing different problems afaict.
thanks,
-Jason
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists