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Date: Wed, 11 May 2016 21:36:27 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Vineet Gupta <vgupta@synopsys.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>, linux-perf-users@vger.kernel.org,
        acme@redhat.com, linux-snps-arc@lists.infradead.org,
        linux-kernel@vger.kernel.org, mingo@kernel.org
Subject: Re: [RFC 2/2] perf/core: change errno for sampling event not
 supported in hardware
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On Mon, May 09, 2016 at 10:53:43PM +0530, Vineet Gupta wrote:

> Right thats what I feared. But hold on, I don't think we need to change the ABI to
> achieve what we want. Gosh why did I even take that path.
> 
> Currently the errno switch case in perf_evsel__open_strerror() in doesn't handle
> ENOTSUPP. So how about we add that - augmented with the same sample_period !0
> check to barf for lack of sampling support.
> 
> Do you see anything wrong with that ?

Should work I think.