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Date: Mon, 13 May 2013 10:14:06 -0600
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Subject: Re: svn commit: r250411 - in head/sys: conf kern sys
From: Will Andrews <will@firepipe.net>
To: John Baldwin <jhb@freebsd.org>
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Cc: Marcel Moolenaar <marcel@freebsd.org>, svn-src-all@freebsd.org,
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On Sun, May 12, 2013 at 7:49 PM, John Baldwin <jhb@freebsd.org> wrote:

> Also, while LK_NOWITESS works fine for lockmgr's API (it already takes a
> flag
> argument), having that sort of thing in our other lock APIs is messier
> (they
> generally do not have flags).  This is why a per-thread flag seemed
> simpler to
> me for this as you don't have to change umpteen locking APIs to add a new
> flags field.
>

Another problem is that approach is far too blunt; in most cases false
positive LORs are specific to a particular pair of instances of locks.
 You'd probably still want to receive witness notifications for other LORs.

--Will.