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Date: Thu, 28 Dec 2017 19:07:08 +0900
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>, Tejun Heo <tj@kernel.org>,
        Petr Mladek <pmladek@suse.com>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Jan Kara <jack@suse.cz>, Andrew Morton <akpm@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Rafael Wysocki <rjw@rjwysocki.net>, Pavel Machek <pavel@ucw.cz>,
        Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>,
        linux-kernel@vger.kernel.org
Subject: Re: [RFC][PATCHv6 00/12] printk: introduce printing kernel thread
Message-ID: <20171228100708.GB892@jagdpanzerIV>
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On (12/28/17 15:48), Sergey Senozhatsky wrote:
[..]
> and I'm actually thinking about returning back the old vprintk_emit()
> behavior
> 
>        vprintk_emit()
>        {
> +         preempt_disable();
>          if (console_trylock())
>              console_unlock();
> +         preempt_enable();
>        }

but am not going to.
it's outside of printk_kthread scope. and, besides, not every CPU which
is looping on console_unlock() came there via printk(). so by disabling
preemption in console_unlock() we cover more cases.

	-ss