Re: [RFC][PATCHv6 00/12] printk: introduce printing kernel thread

From: Sergey Senozhatsky
Date: Mon Dec 18 2017 - 08:39:59 EST


On (12/18/17 14:31), Petr Mladek wrote:
> On Mon 2017-12-18 18:36:15, Sergey Senozhatsky wrote:
> > On (12/15/17 10:08), Petr Mladek wrote:
> > 1) it opens both soft and hard lockup vectors
> >
> > I see *a lot* of cases when CPU that call printk in a loop does not
> > end up flushing its messages. And the problem seems to be - preemption.
> >
> >
> > CPU0 CPU1
> >
> > for_each_process_thread(g, p)
> > printk()
>
> You print one message for each process in a tight loop.
> Is there a code like this?

um... show_state() -> show_state_filter()?
which prints million times more info than a single line per-PID.

-ss