Re: [GIT PULL] trivial for 4.9

From: Joe Perches
Date: Fri Oct 07 2016 - 16:05:26 EST


On Fri, 2016-10-07 at 12:22 -0700, Linus Torvalds wrote:
> On Fri, Oct 7, 2016 at 1:51 AM, Jiri Kosina <jikos@xxxxxxxxxx> wrote:
> > Colin Ian King (5):
> > netfilter: Add missing \n to pr_err() message
> > agp/intel: add missing \n to end of dev_emerg message
> > lightnvm: add missing \n to end of dev_err message
> > nvme: add missing \n to end of dev_warn message
>
>
> We really shouldn't be needing these final '\n' characters any more, afaik.
>
> If the next printk isn't done by the same process, and doesn't have a
> KERN_CONT, the printk machinery should add the newline on its own.
>
> I realize that people have been adding these '\n' characters for a
> while, but is there actually any point to it? They make the code less
> legible, imho. And we actually have a number of logging functions that
> explicitly don't want the newline (eg ext4_warning/error()), so it's
> actually more consistent to *not* have a newline than it is to have
> one.

Not remotely true.

It's _way_ more consistent to use a newline termination.
Macros without the newline are _far_ less common than those
with newlines.

Any printk without a KERN_<level> prefix, and there
are still many of those, can cause random interleaving.

> And if those '\n' characters actually make a difference, that should
> be noted. Because that would imply that the printk logic isn't working
> right.

Not at all. Until printk KERN_<level> uses are mandated,
then these newlines are still useful.