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Subject: Re: [PATCH bpf-next v3 07/14] bpf: Add BPF_FETCH field / create
 atomic_fetch_add instruction
To:     Brendan Jackman <jackmanb@google.com>, <bpf@vger.kernel.org>
CC:     Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        KP Singh <kpsingh@chromium.org>,
        Florent Revest <revest@chromium.org>,
        <linux-kernel@vger.kernel.org>, Jann Horn <jannh@google.com>
References: <20201203160245.1014867-1-jackmanb@google.com>
 <20201203160245.1014867-8-jackmanb@google.com>
From:   Yonghong Song <yhs@fb.com>
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On 12/3/20 8:02 AM, Brendan Jackman wrote:
> This value can be set in bpf_insn.imm, for BPF_ATOMIC instructions,

it is not clear what "this value" means here.
Maybe more specific using "The BPF_FETCH field"?

> in order to have the previous value of the atomically-modified memory
> location loaded into the src register after an atomic op is carried
> out.
> 
> Suggested-by: Yonghong Song <yhs@fb.com>
> Signed-off-by: Brendan Jackman <jackmanb@google.com>

Ack with the above nit.

Acked-by: Yonghong Song <yhs@fb.com>