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Date: Fri, 6 Jul 2012 12:52:57 -0400
From: "Theodore Ts'o" <tytso@mit.edu>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Mackall <mpm@selenic.com>,
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Subject: Re: [PATCH 01/10] random: make 'add_interrupt_randomness()' do
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On Fri, Jul 06, 2012 at 09:24:00AM -0700, Linus Torvalds wrote:
> On Fri, Jul 6, 2012 at 6:01 AM, Theodore Ts'o <tytso@mit.edu> wrote:
> > What in the world is "fast count"?  I've grepped for it,
> > and I can't find it.
> 
> It's your own fast-pool counter that Matt was talking about.

When he said "check it against HZ", it confused me, since there's no
way to compare it against HZ.  But yes, I can certainly not give any
credit for entropy if __IRQF_TIMER is set, or keep track of whether
the previous interrupt had __IRQF_TIMER set in its descriptor.  That's
simple enough.

I thought he was saying there was some way to distinguish between
interrupts triggered by the clock interrupt versus other devices on
the same irq channel --- and I couldn't figure out any to do that in
an architecture independent way.

					- Ted