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From:   Alexei Starovoitov <alexei.starovoitov@gmail.com>
Date:   Tue, 21 Jul 2020 12:17:36 -0700
Message-ID: <CAADnVQJvW7hto4E740Hi9b22wszYLxVwUCDS5jMdQ_2E3==GRQ@mail.gmail.com>
Subject: Re: [PATCH] ebpf: fix parameter naming confusing
To:     YangYuxi <yx.atom1@gmail.com>
Cc:     Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>, Yonghong Song <yhs@fb.com>,
        Andrii Nakryiko <andriin@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@chromium.org>,
        Network Development <netdev@vger.kernel.org>,
        bpf <bpf@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>
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On Thu, Jul 16, 2020 at 7:08 PM YangYuxi <yx.atom1@gmail.com> wrote:
>
> Signed-off-by: YangYuxi <yx.atom1@gmail.com>
> ---
>  kernel/bpf/syscall.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
> index 0fd80ac81f70..300ae16baffc 100644
> --- a/kernel/bpf/syscall.c
> +++ b/kernel/bpf/syscall.c
> @@ -1881,13 +1881,13 @@ struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
>  EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
>
>  bool bpf_prog_get_ok(struct bpf_prog *prog,
> -                           enum bpf_prog_type *attach_type, bool attach_drv)
> +                           enum bpf_prog_type *prog_type, bool attach_drv)
>  {
>         /* not an attachment, just a refcount inc, always allow */
> -       if (!attach_type)
> +       if (!prog_type)
>                 return true;

I think it makes it worse.
Now the comment doesn't match the code.
And attach_drv name also looks out of place.
Technically program type is also an attach type to some degree.
The name could be a bit confusing, but in combination with type:
'enum bpf_prog_type *attach_type'
I think it's pretty clear what these functions are doing.
So I prefer to keep the code as-is.