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Date: Sat, 25 Nov 2000 15:49:25 -0200 (BRDT)
From: Rik van Riel <riel@conectiva.com.br>
To: Roger Larsson <roger.larsson@norran.net>
cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Nigel Gamble <nigel@nrg.org>
Subject: Re: *_trylock return on success?
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On Sat, 25 Nov 2000, Roger Larsson wrote:

> Questions:
>   What are _trylocks supposed to return?

It depends on the type of _trylock  ;(

>   Does spin_trylock and down_trylock behave differently?
>   Why isn't the expected return value documented?

The whole trylock stuff is, IMHO, a big mess. When you
change from one type of trylock to another, you may be
forced to invert the logic of your code since the return
code from the different locks is different.

For bitflags, for example, the trylock returns the state
the bit had before the lock (ie. 1 if the thing was already
locked).

For spinlocks, it'll probably return something else ;/

regards,

Rik
--
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