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Date:   Fri, 24 Jul 2020 07:39:08 -0700
From:   Andi Kleen <ak@linux.intel.com>
To:     peterz@infradead.org
Cc:     kan.liang@linux.intel.com, acme@redhat.com, mingo@kernel.org,
        linux-kernel@vger.kernel.org, jolsa@kernel.org, eranian@google.com,
        alexander.shishkin@linux.intel.com, like.xu@linux.intel.com
Subject: Re: [PATCH V7 07/14] perf/core: Add a new PERF_EV_CAP_COEXIST event
 capability
Message-ID: <20200724143908.GC1180481@tassilo.jf.intel.com>
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> The consequence is that SLOTS must be the leader, is that really a
> problem? You keep providing the {cycles, slots, metric-things} example,

Yes that's a problem. One (major) use case for topdown is to
sample on lots of different events, but always create groups that
also measure topdown metrics for that sampling period. For that we need
other leaders.

-Andi