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Date: Thu, 15 Apr 2010 20:32:05 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
cc: akpm@linux-foundation.org, Ingo Molnar <mingo@elte.hu>,
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       eric.dumazet@gmail.com, adobriyan@gmail.com,
       "David S. Miller" <davem@davemloft.net>
Subject: Re: [patch 1/5] Debugobjects transition check (updated changelog)
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B1;2005;0cOn Tue, 6 Apr 2010, Mathieu Desnoyers wrote:
> Implement a basic state machine checker in the debugobjects.
> 
> This state machine checker detects races and inconsistencies within the "active"
> life of a debugobject. The checker only keeps track of the current state; all
> the state machine logic is kept at the object instance level.
> 
> The checker works by adding a supplementary "unsigned int astate" field to the
> debug_obj structure. It keeps track of the current "active state" of the object.
> 
> The only constraints that are imposed on the states by the debugobjects system
> is that:
> 
> - activation of an object sets the current active state to 0,
> - deactivation of an object expects the current active state to be 0.
> 
> For the rest of the states, the state mapping is determined by the specific
> object instance. Therefore, the logic keeping track of the state machine is
> within the specialized instance, without any need to know about it at the
> debugobject level.
> 
> The current object active state is changed by calling:
> 
> debug_object_active_state(addr, descr, expect, next)
> 
> where "expect" is the expected state and "next" is the next state to move to if
> the expected state is found. A warning is generated if the expected is not
> found.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>

Please feel free to pull that into the rcu branch where the users are
going to be.

Thanks,

	tglx