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Date: Tue, 3 Jan 2017 10:40:59 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Jiri Olsa <jolsa@kernel.org>
Cc: lkml <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@kernel.org>,
        Andi Kleen <andi@firstfloor.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Vince Weaver <vince@deater.net>
Subject: Re: [PATCH 2/4] perf/x86: Fix period for non sampling events
Message-ID: <20170103094059.GC3093@worktop>
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On Wed, Dec 28, 2016 at 02:31:04PM +0100, Jiri Olsa wrote:
> When in counting mode we setup the counter with the
> longest possible period and read the value with read
> syscall.
> 
> We also still setup the PMI to be triggered when such
> counter overflow to reconfigure it.
> 
> We also get PEBS interrupt if such counter has precise_ip
> set (which makes no sense, but it's possible).

I think we should reject non sampling pebs events, as you say they make
no sense what so ever.