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From:   Namhyung Kim <namhyung@kernel.org>
Date:   Tue, 18 Jan 2022 21:01:56 -0800
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Subject: Re: About perf tool set exclude_guest = 1 on guest environment
To:     Eric Lin <eric.lin@sifive.com>
Cc:     linux-kernel <linux-kernel@vger.kernel.org>,
        Jiri Olsa <jolsa@redhat.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Yao Jin <yao.jin@linux.intel.com>,
        Greentime Hu <greentime.hu@sifive.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Vincent Chen <vincent.chen@sifive.com>
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Hello,

On Mon, Jan 17, 2022 at 8:05 PM Eric Lin <eric.lin@sifive.com> wrote:
>
> Hi all,
>
> Currently, I run the perf command 'perf record -e branches:u ls'  and
> 'perf record -e branches ls'. It will set exclude_guest = 1 as below:
>
> # perf record -e branches:u ls
> # perf evlist -v
> branches:u: .., exclude_kernel: 1, exclude_hv: 1,, exclude_guest: 1, ..
>
> # perf record -e branches ls
> # perf evlist -v
> branches: ..., exclude_guest: 1, ...
>
> As I understand it, set exclude_guest =1 will not include guest counting.
> May I ask if I run the above commands as a guest user, should the
> architecture implementation ignore this exclude_guest flags and still
> make perf can count guest events in Linux kernel?

So do you want to run the command in the host?
Then you can use both 'H' and 'G' modifiers like

  # perf record -e branches:HG ls

or (for user-mode only)

  # perf record -e branches:uHG ls

Thanks,
Namhyung