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Message-ID: <c62985530810301705h356decf8oea0db02def2ab3c1@mail.gmail.com>
Date: Fri, 31 Oct 2008 01:05:30 +0100
From: "=?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?=" <fweisbec@gmail.com>
To: "Steven Rostedt" <rostedt@goodmis.org>
Subject: Re: [RFC][PATCH] Make ftrace able to trace function return
Cc: "Ingo Molnar" <mingo@elte.hu>, linux-kernel@vger.kernel.org
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2008/10/30 Steven Rostedt <rostedt@goodmis.org>:
> What about storing the return addresses on the bottom of the stack?
> That is, start at task->stack + sizeof(thread_info), and stack up on that.
> Be careful, there might already be users of that area. This will also need
> to be arch dependent.

But how could I assume there is enough space behind this address to store a long
stack of functions calls for a same thread?
And if an interrupt is raised, would a reference to "current task" be
really consistant?

I don't know much about the bottom stack of the tasks, I'm not sure
about how much
space I can use inside... I should study this field. Who could be the
potential users of this area?