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Date: Wed, 19 Jan 2005 19:01:04 -0800
From: Andrew Morton <akpm@osdl.org>
To: Chris Wedgwood <cw@f00f.org>
Cc: paulus@samba.org, linux-kernel@vger.kernel.org, mingo@elte.hu,
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       hch@infradead.org, wli@holomorphy.com, jbarnes@sgi.com
Subject: Re: [PATCH RFC] 'spinlock/rwlock fixes' V3 [1/1]
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Given the general confusion and the difficulty of defining and
understanding the semantics of these predicates.  And given that the
foo_is_locked() predicates have a history of being used to implement
ghastly kludges, how about we simply nuke this statement:

Chris Wedgwood <cw@f00f.org> wrote:
>
>  	if (!spin_is_locked(&p->sighand->siglock) &&
>  -				!rwlock_is_locked(&tasklist_lock))
>  +				!rwlock_write_locked(&tasklist_lock))

and be done with the whole thing?

I mean, do we really want these things in the kernel anyway?  We've never
needed them before.

If we reeeealy need the debug check, just do

	BUG_ON(read_trylock(...))