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Date: Wed, 4 Oct 2017 16:52:47 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>, pmladek@suse.com,
        sergey.senozhatsky@gmail.com, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH 3/3] early_printk: Add simple serialization to
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On Wed, Oct 04, 2017 at 10:43:54AM -0400, Steven Rostedt wrote:
> 
> My question is not about ordering, but about coherency. Can you have
> one CPU read a variable that goes into cache, and keep using the cached
> variable every time the program asks to read it, instead of going out
> to memory.

No, not on a coherent system.