Re: [PATCH 0/3] zram: Replace pr_* with dev_*

[Minchan Kim <minchan@kernel.org>]

Hello,

On Fri, Aug 07, 2015 at 09:05:20AM +0900, Sergey Senozhatsky wrote:
> On (08/07/15 00:03), Salah Triki wrote:
> > This patchset replaces pr_* with dev_*. dev_* attach kernel messages to the right
> > device. In addition, patchs 1 and 2 add to messages the values of variables that trigger 
> > errors.
> > 
> 
> Hi,
> 
> I'd prefer to leave the messages the way they are. Changing anything
> visible to user space (api, eror codes, error messages, etc.) is a
> very risky business. You change the format of error messages and it
> smells like a big NO-NO.
> 
> 'zram: Cannot initialise lzo compressing backend'
> --> 'block zram0: Cannot initialise lzo compressing backend'
> 
> 
> And there are even more dramatic changes:
> "Cannot change max compression streams\n"
> --> "Cannot change max compression streams to %d\n"
> 
> "Can't change algorithm for initialized device\n"
> --> "Can't change algorithm to %s for initialized device\n"
> 
> 
> People already can have scripts doing `grep "zram:"` on dmesg or
> whatever. We cannot change this anymore.
> 
> This potentially breaks things in user space. So, I NACK the change
> set. Thanks.
> 
> Minchan, any opinion?

Note: I didn't read this patchset in detail so I might be wrong.

When I read description, I couldn't see what's the benefit.
Please write it out.

As well, please write how you change current message. IOW,
before and after.

If the benefit is not enough for me, I don't want to change.

Thanks.

> 
> 	-ss
> 
> > Salah Triki (3):
> >   zram: Replace pr_info with dev_info in max_comp_streams_store
> >   zram: Replace pr_info with dev_info in comp_algorithm_store
> >   zram: Replace pr_* with dev_*
> > 
> >  drivers/block/zram/zram_drv.c | 34 ++++++++++++++++++++--------------
> >  1 file changed, 20 insertions(+), 14 deletions(-)
> > 
> > -- 
> > 1.9.1
> >