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Date: Mon, 19 Jan 2009 14:25:29 +0100
From: "=?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?=" <fweisbec@gmail.com>
To: "Steven Rostedt" <rostedt@goodmis.org>
Subject: Re: [PATCH] ftrace based hard lockup detector
Cc: "Ingo Molnar" <mingo@elte.hu>, linux-kernel@vger.kernel.org
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2009/1/19 Steven Rostedt <rostedt@goodmis.org>:
> Ah, OK, the check is in the function tracer. Hmm, my logdev code had an
> option to enable tracing at early bootup. Instead of using the normal
> memory alloction for the ring buffer, it needed to use alloc_bootmem. I
> wonder if it would be worth it to allow for a tracer to do the same if it
> needs to be allocated early on (before memory is initialized)?
>
> --Steve


Hi Steve,

Yeah I think that would be a good idea.


BTW, tote that for the moment, this hard lockup detector is basic, but
I could even make it relying
to the function graph tracer and then dump the whole stack of
functions called. I think that could
give a more precise backtrace.... (and more human readable).