Date: Wed, 18 Feb 2015 19:22:42 +0100
From: Ingo Molnar <mingo@kernel.org>
To: John Stultz <john.stultz@linaro.org>
Cc: David Ahern <dsahern@gmail.com>, Stephane Eranian <eranian@google.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@elte.hu>,
        "ak@linux.intel.com" <ak@linux.intel.com>,
        Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>,
        Rose Belcher <cel@us.ibm.com>,
        Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>,
        Sonny Rao <sonnyrao@chromium.org>,
        John Mccutchan <johnmccutchan@google.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        =?utf-8?B?UGF3ZcWC?= Moll <mail@pawelmoll.com>
Subject: Re: [PATCH v2 4/4] clock: add perf_clock posix clock
Message-ID: <20150218182242.GC32251@gmail.com>
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* John Stultz <john.stultz@linaro.org> wrote:

> > AFAIK Stephane is not proposing this patch for 
> > inclusion but rather it is an unfortunate necessary 
> > evil. The module exposes perf_clock (ie., local_clock) 
> > to userspace and allows in this case the generation of 
> > samples with a perf timestamp which is required for 
> > proper sorting.
> >
> > I understand this solution is not liked, but it works, 
> > requires no kernel modifications to achieve the end 
> > goal and can be used for kernels going back to at least 
> > 2.6.38 (perhaps earlier, have not checked).
> 
> Yep. And I'm sympathetic to the fact that an alternative 
> solution hasn't made it upstream yet. I'm hopeful Pawel's 
> recent approach will make it in (it seems like it hasn't 
> raised any flags w/ scheduler folks - but I've not always 
> been able to follow the discussion closely).

So if it's part of this series and reviews fine then I'll 
be happy to apply it! Nothing better than having a kernel 
patch and an actual usecase go hand in hand.

Thanks,

	Ingo
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