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Date: Wed, 27 Jan 2016 09:52:34 -0800
From: Alexei Starovoitov <alexei.starovoitov@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Ingo Molnar <mingo@redhat.com>, linux-kernel@vger.kernel.org,
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        Arnaldo Carvalho de Melo <acme@infradead.org>,
        Jiri Olsa <jolsa@kernel.org>, Daniel Borkmann <daniel@iogearbox.net>,
        Wang Nan <wangnan0@huawei.com>
Subject: Re: [PATCH v2] perf: Synchronously cleanup child events
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On Wed, Jan 27, 2016 at 10:58:22AM +0100, Peter Zijlstra wrote:
> 
> > Meaning there gotta be always a user space process
> > that will be holding perf_event FDs.
> 
> By using fget() the BPF array thing will hold the FDs, right? I mean
> once you do a full fget() userspace can go and kill itself, the struct
> file will persists.

Right. I mistakenly thought that fget() will prevent the task
from freeing or some fs/directory resources will be hanging.
It's from anon_inode. So all good. All concerns cleared.