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From:   John Garry <john.garry@huawei.com>
Subject: perf tool pmuevents: About arm64 a76 JSON
CC:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
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To:     <James.Clark@arm.com>
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Date:   Wed, 2 Oct 2019 16:37:00 +0100
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Hi,

I noticed that the JSON to support a76 pmu events was added recently.

May I ask why we add explicit support for the common architectural and 
microarch events (event id 0x0-0x3f), when they would be already 
available from the kernel pmuv3 driver?

The ampere emag jsons do similar. Others don't.

The only advantage I see is that we have an event description, but I am 
sure how useful that is.

Cheers,
John