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Subject: Re: [PATCH 0/2] perf: Allow closing siblings' file descriptors
To:     Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Arnaldo Carvalho de Melo <acme@redhat.com>
Cc:     Ingo Molnar <mingo@redhat.com>, linux-kernel@vger.kernel.org,
        Jiri Olsa <jolsa@kernel.org>, alexey.budankov@linux.intel.com
References: <20200708151635.81239-1-alexander.shishkin@linux.intel.com>
From:   Adrian Hunter <adrian.hunter@intel.com>
Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki,
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Message-ID: <32ad7700-3d4e-6c20-31c9-8b002fea5cbc@intel.com>
Date:   Thu, 6 Aug 2020 09:15:08 +0300
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On 8/07/20 6:16 pm, Alexander Shishkin wrote:
> Hi guys,
> 
> I've been looking at reducing the number of open file descriptors per perf
> session. If we retain one descriptor per event, in a large group they add
> up. At the same time, we're not actually using them for anything after the
> SET_OUTPUT and maybe SET_FILTER ioctls. So, this series is a stab at that.

I am wondering if instead we should be looking at creating a kernel API that
allows associating a multitude of tracepoints with a single event.  Thoughts
anyone?