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Date: Thu, 23 Mar 2017 09:51:43 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>, Petr Mladek <pmladek@suse.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        "Rafael J . Wysocki" <rjw@rjwysocki.net>, linux-kernel@vger.kernel.org,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Subject: Re: [RFC][PATCH 0/4] printk: introduce printing kernel thread
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On Thu, Mar 23, 2017 at 01:09:58PM +0900, Sergey Senozhatsky wrote:
> Hello Peter,
> 
> thanks for taking a look.
> 
> On (03/22/17 18:59), Peter Zijlstra wrote:
> > On Mon, Mar 06, 2017 at 09:45:50PM +0900, Sergey Senozhatsky wrote:
> > >  sysrq is potentially even trickier. can we always wake_up() kernel
> > >  thread from sysrq? there probably might be cases when we can't rely
> > >  on the scheduler.
> > 
> > sysrq runs from interrupt context, right? Should be able to do wakeups.
> 
> what I though about was -
> 	what if there are 'misbehaving' higher prio tasks all the time?
> 	the existing sysrq would attempt to do printing from irq context
> 	so it doesn't care about run queues.
> 
> does it make sense to you?

Ah, that's what you meant. Yeah, dunno, I'm still unconvinced about the
whole printk thread thing. Also those function names are horrifically
long.