linux-kernel - Re: [PATCH 3/4] libbpf: break loop earlier

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Message-ID: <20171227190042.hwxk6ccazdtnob77@ast-mbp>
Date:   Wed, 27 Dec 2017 11:00:43 -0800
From:   Alexei Starovoitov <alexei.starovoitov@...il.com>
To:     Eric Leblond <eric@...it.org>
Cc:     netdev@...r.kernel.org, daniel@...earbox.net,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/4] libbpf: break loop earlier

On Wed, Dec 27, 2017 at 07:02:28PM +0100, Eric Leblond wrote:
> Get out of the loop when we have a match.
> 
> Signed-off-by: Eric Leblond <eric@...it.org>
> ---
>  tools/lib/bpf/libbpf.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index 5fe8aaa2123e..d263748aa341 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -412,6 +412,7 @@ bpf_object__init_prog_names(struct bpf_object *obj)
>  					   prog->section_name);
>  				return -LIBBPF_ERRNO__LIBELF;
>  			}
> +			break;

why this is needed?
The top of the loop is:
 for (si = 0; si < symbols->d_size / sizeof(GElf_Sym) && !name;

so as soon as name is found the loop will exit.
I agree that the loop structure is non-standard is confusing,
but adding break here will make it even more so.
If 'break' is added then '&& !name' should be removed.