Subject: Re: [PATCH 1/19] MUTEX: Introduce simple mutex implementation
From: Thomas Gleixner <tglx@linutronix.de>
Reply-To: tglx@linutronix.de
To: Linus Torvalds <torvalds@osdl.org>
Cc: David Howells <dhowells@redhat.com>, Nikita Danilov <nikita@clusterfs.com>,
       Alan Cox <alan@lxorguk.ukuu.org.uk>, Andrew Morton <akpm@osdl.org>,
       pj@sgi.com, Ingo Molnar <mingo@elte.hu>, hch@infradead.org,
       arjan@infradead.org, matthew@wil.cx, linux-kernel@vger.kernel.org,
       linux-arch@vger.kernel.org
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Organization: Linutronix
Date: Thu, 15 Dec 2005 18:04:54 +0100
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On Thu, 2005-12-15 at 08:28 -0800, Linus Torvalds wrote:
> I would suggest that if you create a new "mutex" type, you just keep the 
> lower-case name. Don't re-use the DECLARE_MUTEX format, just do
> 
> 	struct mutex my_mutex = UNLOCKED_MUTEX;
> 
> for new code that uses the new stuff.
> 
> Think about it a bit. We don't have DECLARE_SPINLOCK either. Why?

Well, we have DEFINE_SPINLOCK() and we should have a matching one for
mutexes DEFINE_MUTEX().

The reason is that you can implement complex initialization for
debugging or extensions which can't be done by a var = INITIALZER,
because you dont have a reference to var.

	tglx


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