DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 76E8421896
Date: Tue, 19 Dec 2017 11:52:38 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Dhaval Giani <dhaval.giani@oracle.com>,
        LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] lockdep: Show up to three levels for a deadlock
 scenario
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On Tue, 19 Dec 2017 17:46:19 +0100
Peter Zijlstra <peterz@infradead.org> wrote:


> It really isn't that hard, Its mostly a question of TL;DR.
> 
> #0 is useless and should be thrown out
> #1 shows where we take #1 while holding #0
> ..
> #n shows where we take #n while holding #n-1
> 
> And the bottom callstack shows where we take #0 while holding #n. Which
> gets you a nice circle in your graph, which spells deadlock.
> 
> Plenty people have shown they get this stuff.


Then I suggest that you can either take my patch to improve the
visual or remove the visual completely, as nobody cares about it.

-- Steve