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Date: Fri, 3 Nov 2017 07:54:56 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: John Hubbard <jhubbard@nvidia.com>
Cc: Vlastimil Babka <vbabka@suse.cz>, LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>, <akpm@linux-foundation.org>,
        <linux-mm@kvack.org>, Cong Wang <xiyou.wangcong@gmail.com>,
        Dave Hansen <dave.hansen@intel.com>,
        Johannes Weiner <hannes@cmpxchg.org>, Mel Gorman <mgorman@suse.de>,
        Michal Hocko <mhocko@kernel.org>, Petr Mladek <pmladek@suse.com>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        "yuwang.yuwang" <yuwang.yuwang@alibaba-inc.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Jan Kara <jack@suse.cz>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Subject: Re: [PATCH v3] printk: Add console owner and waiter logic to load
 balance console writes
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On Fri, 3 Nov 2017 07:54:04 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> The new waiter gets set only if there isn't already a waiter *and*
> there is an owner that is not current (and with the printk_safe_enter I
> don't think that is even needed).
> 
> +				while (!READ_ONCE(console_waiter))
> +					cpu_relax();

I still need to fix the patch. I cut and pasted the bad version. This
should have been:

	while (READ_ONCE(console_waiter))
		cpu_relax();

-- Steve