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Date: Thu, 22 Oct 2015 09:56:11 +0800
From: "Wangnan (F)" <wangnan0@huawei.com>
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To: Peter Zijlstra <peterz@infradead.org>,
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CC: xiakaixu <xiakaixu@huawei.com>, <davem@davemloft.net>, <acme@kernel.org>,
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Subject: Re: [PATCH V5 1/1] bpf: control events stored in PERF_EVENT_ARRAY
 maps trace data output when perf sampling
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Hi Alexei,

On 2015/10/21 21:42, Wangnan (F) wrote:
>
>
> One alternative solution I can image is to attach a BPF program
> at sampling like kprobe, and return 0 if we don't want sampling
> take action. Thought?

Do you think attaching BPF programs to sampling is an acceptable idea?

Thank you.

> Actually speaking I don't like it very much
> because the principle of soft-disable is much simpler and safe, but
> if you really like it I think we can try.