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Date: Mon, 23 Dec 2013 14:10:52 +0100
From: Frederic Weisbecker <fweisbec@gmail.com>
To: David Ahern <dsahern@gmail.com>
Cc: Joseph Schuchart <joseph.schuchart@tu-dresden.de>,
        Ingo Molnar <mingo@kernel.org>,
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        Arnaldo Carvalho de Melo <acme@ghostprotocols.net>,
        thomas.ilsche@tu-dresden.de, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Perf: Correct Assumptions about Sample Timestamps in
 Passes
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On Fri, Dec 20, 2013 at 10:09:53AM -0700, David Ahern wrote:
> On 12/20/13, 5:27 AM, Joseph Schuchart wrote:
> >I know this comes late, but: As far as I can see, your change does not
> >preserve the logic of the code I suggested. The idea was to first gather
> >all the maximum timestamps of all cpus (that is, the last timestamp seen
> >on each cpu) and then determine the minimum of these maxima. These are
> >two distinct steps that I think cannot be combined in one update. Your
> 
>  A number of people have reported similar problems -- timestamps
> below last flush time. This approach would solve that problem for
> data processed from files, so it would be a good improvement.

Could it be near what you're looking for?

https://lkml.org/lkml/2012/2/18/53