From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Snitzer Subject: Re: device-mapper: use dynamic debug instead of compile-time config option Date: Wed, 13 May 2020 13:10:43 -0400 Message-ID: <20200513171042.GA20324@redhat.com> References: <20200513070843.71528-1-hare@suse.de> <5357d0d6-12cb-9585-36ae-9aec206eebb4@suse.de> <20200513162502.GA20131@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com Content-Disposition: inline To: Hannes Reinecke Cc: Damien Le Moal , "dm-devel@redhat.com" List-Id: dm-devel.ids On Wed, May 13 2020 at 1:01pm -0400, Hannes Reinecke wrote: > On 5/13/20 6:25 PM, Mike Snitzer wrote: > >On Wed, May 13 2020 at 7:10am -0400, > >Hannes Reinecke wrote: > > > >>On 5/13/20 11:41 AM, Damien Le Moal wrote: > >>>On 2020/05/13 16:10, Hannes Reinecke wrote: > >>>>Switch to use dynamic debug to avoid having recompile the kernel > >>>>just to enable debugging messages. > >>>> > >>>>Signed-off-by: Hannes Reinecke > >>>>--- > >>>> include/linux/device-mapper.h | 7 +------ > >>>> 1 file changed, 1 insertion(+), 6 deletions(-) > >>>> > >>>>diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h > >>>>index e2d506dd805e..3d4365fd3001 100644 > >>>>--- a/include/linux/device-mapper.h > >>>>+++ b/include/linux/device-mapper.h > >>>>@@ -556,13 +556,8 @@ void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size); > >>>> #define DMINFO(fmt, ...) pr_info(DM_FMT(fmt), ##__VA_ARGS__) > >>>> #define DMINFO_LIMIT(fmt, ...) pr_info_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) > >>>>-#ifdef CONFIG_DM_DEBUG > >>> > >>>Can we remove this from Kconfig as a config option ? > >>> > >>No, we can't, it's being used by dm-snap and dm-integrity. > > > >Yeah, they provide additional debugging if its set. > > > >But shouldn't we preserve old-style DMDEBUG if CONFIG_DM_DEBUG is set > >(compile time printing of debugging) but if not set, use dynamic > >debugging? > > > >Think I'd prefer that as the incremental improvement... thoughts? > > > Works for me; I just don't want to recompile the kernel anytime I > need to debug device-mapper stuff. > > Will be resending. Does the use of pr_debug() cause missing newlines (with your patch)? Only thought to ask this because I'm chasing another DM issue at the moment and happened to see __dm_suspend()'s use of pr_debug() includes an explicit extra \n. Mike