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Date: Tue, 29 Apr 2008 22:23:02 +0300
From: "Pekka Enberg" <penberg@cs.helsinki.fi>
To: "Christoph Lameter" <clameter@sgi.com>
Subject: Re: [2/2] vmallocinfo: Add caller information
Cc: "Arjan van de Ven" <arjan@infradead.org>, "Ingo Molnar" <mingo@elte.hu>,
       akpm@linux-foundation.org, linux-mm@kvack.org,
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       "Linus Torvalds" <torvalds@linux-foundation.org>,
       "Peter Zijlstra" <a.p.zijlstra@chello.nl>
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On Tue, Apr 29, 2008 at 10:09 PM, Christoph Lameter <clameter@sgi.com> wrote:
>  Well so we display out of whack backtraces? There are also issues on
>  platforms that do not have a stack in the classic sense (rotating register
>  file on IA64 and Sparc64 f.e.). Determining a backtrace can be very
>  expensive.

I think that's the key question here whether we need to enable this on
production systems? If yes, why? If it's just a debugging aid, then I
see Ingo's point of save_stack_trace(); otherwise the low-overhead
__builtin_return_address() makes more sense.

And btw, why is this new file not in /sys/kernel....?