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Date: Sun, 8 Jun 2014 21:35:53 -0400
From: "Theodore Ts'o" <tytso@mit.edu>
To: George Spelvin <linux@horizon.com>
Cc: hpa@linux.intel.com, price@mit.edu, linux-kernel@vger.kernel.org,
        mingo@kernel.org
Subject: Re: [RFC PATCH] drivers/char/random.c: Is reducing locking range
 like this safe?
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On Sun, Jun 08, 2014 at 08:05:24PM -0400, George Spelvin wrote:
> 
> The problem I started trying to solve is readers (entropy extractors)
> monopolizing the pool lock and stalling writers (entropy mixers), which
> are supposed to be fast and low overhead.

Which writer are you worried about, specifically?  A userspace write
to /dev/random from rgnd?

And have you measured this to be something significant, or is this a
theoretical concern.  If you've measured it, what's the conditions
where this is stalling an entropy mixer a significant amount of time?

      	      	       	  	  	  - Ted
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