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Date: Wed, 8 Oct 2003 11:15:18 +0100
From: Bruce M Simpson <bms@spc.org>
To: Pawel Jakub Dawidek <nick@garage.freebsd.pl>
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Subject: Re: Dynamic reads without locking.
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On Wed, Oct 08, 2003 at 12:12:22PM +0200, Pawel Jakub Dawidek wrote:
> But I'm not talking about non-atomic reads. What I'm want to show is that
> even atomic read (without lock) is dangerous in some cases.
>=20
> +> If you don't care about occasionally reading false data (for statistic=
s or
> +> such stuff) you can go without the lock.
>=20
> I'm afraid that many developers thinks that atomic reads are always safe
> without locks (there are many such reads in sources). I hope I'm wrong.

Correcto. A while back peter@ and I discussed this. If you can think of
such places, share what you've found, and let's discuss fixing the offending
code so as to avoid nasty races.

BMS

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