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Subject: Re: Perf and ftrace [was Re: PyTimechart]
From: Peter Zijlstra <peterz@infradead.org>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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On Wed, 2010-05-12 at 14:04 -0400, Mathieu Desnoyers wrote:
> Can't we keep multiple references to each page ? (shared page) so it's still in
> the buffer, also accessed by mmap(), and in addition accessed by splice.

I'm not sure, the problem seems to be that a splice-consumer might want
to inject the page into a whole different address-space, over-writing
page->mapping/->index etc.