Date: Mon, 19 May 2003 07:28:22 -0700
From: "Martin J. Bligh" <mbligh@aracnet.com>
To: ptb@it.uc3m.es, William Lee Irwin III <wli@holomorphy.com>
cc: linux-kernel@vger.kernel.org
Subject: Re: recursive spinlocks. Shoot.
Message-ID: <34270000.1053354500@[10.10.2.4]>
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References: <200305181724.h4IHOHU24241@oboe.it.uc3m.es>
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> That's a problem looking for a solution!  No, the reason for wanting a
> recursive spinlock is that nonrecursive locks make programming harder.

And more correct.
 
> Though I've got quite good at finding and removing deadlocks in my old
> age, there are still two popular ways that the rest of the world's
> prgrammers often shoot themselves in the foot with a spinlock:
> 
>    a) sleeping while holding the spinlock
>    b) taking the spinlock in a subroutine while you already have it

So ... we should BUG() on both.

M.
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