From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@elte.hu>
Subject: Re: [mmotm and linux-next][PATCH] irq: enclose irq_desc_lock_class
	in CONFIG_LOCKDEP
Date: Tue, 16 Dec 2008 11:23:40 +0100
Message-ID: <20081216102340.GA1003@elte.hu>
References: <20081216170635.DBB8.KOSAKI.MOTOHIRO@jp.fujitsu.com> <20081216003428.43d37b6b.akpm@linux-foundation.org> <20081216101827.GB27481@elte.hu>
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To: Andrew Morton <akpm@linux-foundation.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>, Yinghai Lu <yhlu.kernel@gmail.com>, LKML <linux-kernel@vger.kernel.org>, linux-next <linux-next@vger.kernel.org>


* Ingo Molnar <mingo@elte.hu> wrote:

> > >  #include "internals.h"
> > >  
> > > +#ifdef CONFIG_LOCKDEP
> > >  /*
> > >   * lockdep: we want to handle all irq_desc locks as a single lock-class:
> > >   */
> > >  static struct lock_class_key irq_desc_lock_class;
> > > +#endif
> > >  
> > >  /**
> > >   * handle_bad_irq - handle spurious and unhandled irqs
> > > 
> > 
> > No, lockdep.h (which we forgot to include) already handles that:
> > 
> > # define lockdep_set_class(lock, key)		do { (void)(key); } while (0)
> > 
> > the problem is that the code which references irq_desc_lock_class is
> > inside #ifdef CONFIG_SPARSE_IRQ, so this is a better fix:
> 
> agreed that this is the better fix - applied to tip/irq/sparseirq, 
> thanks!

actually, this breaks the build on !SPARSEIRQ because we will use that 
class in the non-sparseirq case. So we've converted a build warning to a 
build failure ;-)

	Ingo