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From:   Alexei Starovoitov <alexei.starovoitov@gmail.com>
Date:   Wed, 3 Nov 2021 21:27:09 -0700
Message-ID: <CAADnVQ+62fOzO8nS_rbTqkFtfWGj06bT1XDUFhdAxY8Lx3OR4g@mail.gmail.com>
Subject: Re: [RFC PATCH v3 0/3] Introduce BPF map tracing capability
To:     Yonghong Song <yhs@fb.com>
Cc:     Joe Burton <jevburton.kernel@gmail.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Network Development <netdev@vger.kernel.org>,
        bpf <bpf@vger.kernel.org>, Petar Penkov <ppenkov@google.com>,
        Stanislav Fomichev <sdf@google.com>,
        Joe Burton <jevburton@google.com>
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On Wed, Nov 3, 2021 at 9:23 PM Yonghong Song <yhs@fb.com> wrote:
>
> I checked with a few llvm compiler engineers in Facebook.
> They mentioned there is nothing preventing compiler from doing
> optimization like poking inside the noinline function and doing
> some optimization based on that knowledge.

Interesting. Thanks for digging in.
Good to know!