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Date:   Fri, 18 Sep 2020 09:32:19 +0900
From:   Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
To:     Marc Zyngier <maz@kernel.org>
Cc:     Leo Yan <leo.yan@linaro.org>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Will Deacon <will@kernel.org>,
        John Garry <john.garry@huawei.com>,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Suleiman Souhlal <suleiman@google.com>,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCHv3] perf kvm: add kvm-stat for arm64
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On (20/09/17 12:53), Marc Zyngier wrote:
> Feel free to add a *new* tracepoint instead.

Wouldn't we want a whole bunch of new tracepoints in this case?
(almost all of the existing ones with the extra vcpu_id field).
Right now we have 3 types of events:
- events with no vcpu at all        // nil
- events with vcpu_pc               // "0x%016lx", __entry->vcpu_pc
- events with (void *)vcpu          // "vcpu: %p", __entry->vcpu

It might be helpful if we could filter out events by vcpu_id.
But this, basically, doubles the number of events in the ringbuffer.

	-ss