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Subject: Re: svn commit: r238907 - projects/calloutng/sys/kern
From: Adrian Chadd <adrian@freebsd.org>
To: attilio@freebsd.org
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Cc: src-committers@freebsd.org, John Baldwin <jhb@freebsd.org>,
 Jeff Roberson <jeff@freebsd.org>, Florian Smeets <flo@freebsd.org>,
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X-List-Received-Date: Mon, 29 Oct 2012 02:25:34 -0000

So colour me a bit silly, but why didn't you use an atomic here for
that single variable, rather than a memory barrier alone?

I feel slightly nitpicky about it, but this stuff rubs me up slightly
the wrong way, same as the "don't worry about using atomics for 32 bit
set/reads, as those are guaranteed to be atomic on all of the
platforms we use" done what, last year or so.

Thanks,



Adrian