| From: |
| Linus Torvalds <torvalds-AT-linux-foundation.org> |
| To: |
| Sergey Senozhatsky <sergey.senozhatsky.work-AT-gmail.com> |
| Subject: |
| Re: printk: what is going on with additional newlines? |
| Date: |
| Tue, 29 Aug 2017 10:12:22 -0700 |
| Message-ID: |
| <CA+55aFyzR4LKhJKLFgvvd9OTsos2_g4-9fova782BX4kyA3bLA@mail.gmail.com> |
| Cc: |
| Pavel Machek <pavel-AT-ucw.cz>, Sergey Senozhatsky <sergey.senozhatsky-AT-gmail.com>, Petr Mladek <pmladek-AT-suse.com>, Steven Rostedt <rostedt-AT-goodmis.org>, Jan Kara <jack-AT-suse.cz>, Andrew Morton <akpm-AT-linux-foundation.org>, Jiri Slaby <jslaby-AT-suse.com>, Andreas Mohr <andi-AT-lisas.de>, Tetsuo Handa <penguin-kernel-AT-i-love.sakura.ne.jp>, Linux Kernel Mailing List <linux-kernel-AT-vger.kernel.org> |
On Tue, Aug 29, 2017 at 10:00 AM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> I refuse to help those things. We mis-designed things
Actually, let me rephrase that:
It might actually be a good idea to help those things, by making
helper functions available that do the marshalling.
So not calling "printk()" directly, but having a set of simple
"buffer_print()" functions where each user has its own buffer, and
then the "buffer_print()" functions will help people do nicely output
data.
So if the issue is that people want to print (for example) hex dumps
one character at a time, but don't want to have each character show up
on a line of their own, I think we might well add a few functions to
help dop that.
But they wouldn't be "printk". They would be the buffering functions
that then call printk when tyhey have buffered a line.
That avoids the whole nasty issue with printk - printk wants to show
stuff early (because _maybe_ it's critical) and printk wants to make
log records with timestamps and loglevels. And printk has serious
locking issues that are really nasty and fundamental.
A private buffer has none of those issues.
Linus
