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Subject: Re: [patch] spinlocks: remove 'volatile'
From: Arjan van de Ven <arjan@infradead.org>
To: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>, Linus Torvalds <torvalds@osdl.org>,
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Date: Thu, 06 Jul 2006 11:34:31 +0200
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> 
> Shouldn't the __raw_read_can_lock and __raw_write_can_lock macros be changed too, just
> to make sure the value gets read every single time if it's used in a loop?
> Just like the __raw_spin_is_locked already has a (volatile signed char * cast)?
> -

it shouldn't get a volatile case imo, just a barrier().
A barrier() at least has well defined semantics, unlike volatile...