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Date:   Mon, 17 Apr 2023 13:02:21 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Adrian Hunter <adrian.hunter@intel.com>
Cc:     Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Ian Rogers <irogers@google.com>,
        linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH RFC 0/5] perf: Add ioctl to emit sideband events
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On Fri, Apr 14, 2023 at 11:22:55AM +0300, Adrian Hunter wrote:
> Hi
> 
> Here is a stab at adding an ioctl for sideband events.
> 
> This is to overcome races when reading the same information
> from /proc.

What races? Are you talking about reading old state in /proc the kernel
delivering a sideband event for the new state, and then you writing the
old state out?

Surely that's something perf tool can fix without kernel changes?