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Subject: Re: [PATCH perf,bpf 5/5] perf util: generate bpf_prog_info_event for
 short living bpf programs
To:     Alexei Starovoitov <alexei.starovoitov@gmail.com>,
        Song Liu <songliubraving@fb.com>
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        ast@kernel.org, daniel@iogearbox.net, acme@kernel.org,
        peterz@infradead.org, kernel-team@fb.com
References: <20181121195502.3259930-1-songliubraving@fb.com>
 <20181121195502.3259930-6-songliubraving@fb.com>
 <20181121221145.2cxph7zv27x7lbg6@ast-mbp>
From:   David Ahern <dsahern@gmail.com>
Message-ID: <1fb2247a-debe-cdc4-2fec-76526dd07dab@gmail.com>
Date:   Sat, 24 Nov 2018 15:17:12 -0700
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On 11/21/18 3:11 PM, Alexei Starovoitov wrote:
> On Wed, Nov 21, 2018 at 11:55:02AM -0800, Song Liu wrote:
>> This patch enables perf-record to listen to bpf_event and generate
>> bpf_prog_info_event for bpf programs loaded and unloaded during
>> perf-record run.
>>
>> To minimize latency between bpf_event and following bpf calls, separate
>> mmap with watermark of 1 is created to process these vip events. Then
>> a separate dummy event is attached to the special mmap. A separate thread
>> is used to only poll bpf events.
>>
>> By default, perf-record will listen to bpf_event. Option no-bpf-event is
>> added in case the user would opt out.
> 
> I think only default perf-record for sampling should include it.
> perf record -e for tracepoints, kprobes and anything else should imply no-bpf-event.
> 

It should default off for those, but as I have said before users should
be able to add bpf load and unload events to the mix of tracepoints,
probes, etc they are monitoring.