Re: [PATCH] improve spinlock debugging

[David S. Miller]

   From: Manfred Spraul <[e-mail]>
   Date: Mon, 03 Dec 2001 21:10:27 +0100
   
   Which other runtime checks are possible?
   Tests for correct _irq usage are not possible, several drivers use
   disable_irq().

Keep track of how many locks are being held at once, and check if it
is zero at switch_to() time.  You can also do this to measure things
like max number of locks held at once and other statistics.

I added the first bit to sparc64 while hunting down a bug.