From mboxrd@z Thu Jan  1 00:00:00 1970
Subject: Re: [PATCH] jffs2: Move erasing from write_super to GC.
From: David Woodhouse <dwmw2@infradead.org>
To: Joakim Tjernlund <joakim.tjernlund@transmode.se>
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Date: Wed, 19 May 2010 11:05:31 +0100
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On Wed, 2010-05-19 at 11:47 +0200, Joakim Tjernlund wrote:
> 
> This looks like a typo and I had to change that to:
> BUG_ON(spin_is_locked(&c->erase_completion_lock)); 

Hm, no -- we want it to BUG() if the spinlock is _NOT_ locked.

You're building on UP, without preemption or spinlock debugging. In that
case, spinlocks are a no-op. So spin_trylock() _always_ succeeds, and
spin_is_locked() always returns 0.

It should be lockdep_assert_held(), I think.

-- 
David Woodhouse                            Open Source Technology Centre
David.Woodhouse@intel.com                              Intel Corporation