BPF List
 help / color / mirror / Atom feed
From: Martin KaFai Lau <martin.lau@linux.dev>
To: Kui-Feng Lee <kuifeng@meta.com>
Cc: bpf@vger.kernel.org, ast@kernel.org, song@kernel.org,
	kernel-team@meta.com, andrii@kernel.org, sdf@google.com
Subject: Re: [PATCH bpf-next v7 4/8] libbpf: Create a bpf_link in bpf_map__attach_struct_ops().
Date: Fri, 17 Mar 2023 11:44:30 -0700	[thread overview]
Message-ID: <228648b6-c6f0-d194-2e72-c7aaf095a35d@linux.dev> (raw)
In-Reply-To: <20230316023641.2092778-5-kuifeng@meta.com>

On 3/15/23 7:36 PM, Kui-Feng Lee wrote:
> @@ -11590,31 +11631,32 @@ struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map)
>   	if (!link)
>   		return libbpf_err_ptr(-EINVAL);
>   
> -	st_ops = map->st_ops;
> -	for (i = 0; i < btf_vlen(st_ops->type); i++) {
> -		struct bpf_program *prog = st_ops->progs[i];
> -		void *kern_data;
> -		int prog_fd;
> +	/* kern_vdata should be prepared during the loading phase. */
> +	err = bpf_map_update_elem(map->fd, &zero, map->st_ops->kern_vdata, 0);
> +	if (err) {

It should not fail for BPF_F_LINK struct_ops when err is EBUSY.
The struct_ops map can attach, detach, and then attach again.

It needs a test for this case.

> +		free(link);
> +		return libbpf_err_ptr(err);
> +	}


  reply	other threads:[~2023-03-17 18:44 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-16  2:36 [PATCH bpf-next v7 0/8] Transit between BPF TCP congestion controls Kui-Feng Lee
2023-03-16  2:36 ` [PATCH bpf-next v7 1/8] bpf: Retire the struct_ops map kvalue->refcnt Kui-Feng Lee
2023-03-17 16:47   ` Martin KaFai Lau
2023-03-17 20:41     ` Kui-Feng Lee
2023-03-16  2:36 ` [PATCH bpf-next v7 2/8] net: Update an existing TCP congestion control algorithm Kui-Feng Lee
2023-03-17 15:23   ` Daniel Borkmann
2023-03-17 17:18     ` Martin KaFai Lau
2023-03-17 17:23       ` Daniel Borkmann
2023-03-17 21:46         ` Kui-Feng Lee
2023-03-17 23:07     ` Kui-Feng Lee
2023-03-16  2:36 ` [PATCH bpf-next v7 3/8] bpf: Create links for BPF struct_ops maps Kui-Feng Lee
2023-03-17 18:10   ` Martin KaFai Lau
2023-03-17 20:52     ` Kui-Feng Lee
2023-03-16  2:36 ` [PATCH bpf-next v7 4/8] libbpf: Create a bpf_link in bpf_map__attach_struct_ops() Kui-Feng Lee
2023-03-17 18:44   ` Martin KaFai Lau [this message]
2023-03-17 21:00     ` Kui-Feng Lee
2023-03-17 22:23   ` Andrii Nakryiko
2023-03-17 23:48     ` Kui-Feng Lee
2023-03-16  2:36 ` [PATCH bpf-next v7 5/8] bpf: Update the struct_ops of a bpf_link Kui-Feng Lee
2023-03-17 19:23   ` Martin KaFai Lau
2023-03-17 21:39     ` Kui-Feng Lee
2023-03-18  1:11     ` Kui-Feng Lee
2023-03-18  5:38       ` Martin KaFai Lau
2023-03-17 22:27   ` Andrii Nakryiko
2023-03-18  0:41     ` Kui-Feng Lee
2023-03-16  2:36 ` [PATCH bpf-next v7 6/8] libbpf: Update a bpf_link with another struct_ops Kui-Feng Lee
2023-03-17 19:42   ` Martin KaFai Lau
2023-03-17 21:40     ` Kui-Feng Lee
2023-03-17 22:33   ` Andrii Nakryiko
2023-03-18  1:17     ` Kui-Feng Lee
2023-03-16  2:36 ` [PATCH bpf-next v7 7/8] libbpf: Use .struct_ops.link section to indicate a struct_ops with a link Kui-Feng Lee
2023-03-17 22:35   ` Andrii Nakryiko
2023-03-16  2:36 ` [PATCH bpf-next v7 8/8] selftests/bpf: Test switching TCP Congestion Control algorithms Kui-Feng Lee

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=228648b6-c6f0-d194-2e72-c7aaf095a35d@linux.dev \
    --to=martin.lau@linux.dev \
    --cc=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=kernel-team@meta.com \
    --cc=kuifeng@meta.com \
    --cc=sdf@google.com \
    --cc=song@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox