Re: [RFC][PATCHv3 2/5] printk: introduce printing kernel thread

From: Sergey Senozhatsky
Date: Fri Jun 30 2017 - 10:09:58 EST


On (06/30/17 15:16), Petr Mladek wrote:
[..]
>
> I wonder if I could add some counter into task_struct.
> It might be configurable. I am not sure if people would
> want this enabled on production systems where the level
> of messages should be lower anyway.

I don't think it really matters which one of the tasks has issued way
too many printk()-s. it's the state of the logbuf that matters after
all. was it one task or 5 tasks, or 15 that pushed logbuf far ahead of
console_seq, we need to throttle all of new printk() calls anyway.
just because logbuf is already too far and we need to give console a
chache to catch up. so let's activate throttling based on the logbuf
state (those seq numbers).

-ss