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Date:   Tue, 28 May 2019 16:05:18 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Liang, Kan" <kan.liang@linux.intel.com>
Cc:     mingo@kernel.org, acme@redhat.com, vincent.weaver@maine.edu,
        linux-kernel@vger.kernel.org, alexander.shishkin@linux.intel.com,
        ak@linux.intel.com, jolsa@redhat.com, eranian@google.com
Subject: Re: [PATCH V2 1/3] perf/x86: Disable non generic regs for
 software/probe events
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On Tue, May 28, 2019 at 09:33:40AM -0400, Liang, Kan wrote:
> Uncore PMU doesn't support sampling. It will return -EINVAL.
> There is no regs support for counting. The request will be ignored.
> 
> I think current check for uncore is good enough.

breakpoints then.. There's also no guarantee you covered all software
events, and the core rewrite will allow other per-task/sampling PMUs
too.

The approach you take is just not complete, don't do that.