BPF List
 help / color / mirror / Atom feed
From: "Alexei Starovoitov" <alexei.starovoitov@gmail.com>
To: "Kuniyuki Iwashima" <kuniyu@google.com>,
	"Daniel Borkmann" <daniel@iogearbox.net>,
	"Andrii Nakryiko" <andrii@kernel.org>,
	"Martin KaFai Lau" <martin.lau@linux.dev>,
	"Eduard Zingerman" <eddyz87@gmail.com>,
	"Kumar Kartikeya Dwivedi" <memxor@gmail.com>
Cc: "Yonghong Song" <yonghong.song@linux.dev>,
	"John Fastabend" <john.fastabend@gmail.com>,
	"Stanislav Fomichev" <sdf@fomichev.me>,
	"Eric Dumazet" <edumazet@google.com>,
	"Neal Cardwell" <ncardwell@google.com>,
	"Willem de Bruijn" <willemb@google.com>,
	"Tenzin Ukyab" <ukyab@berkeley.edu>,
	"Clément Léger" <cleger@meta.com>,
	"Kuniyuki Iwashima" <kuni1840@gmail.com>,
	bpf@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: [PATCH v2 bpf-next 3/8] bpf: tcp: Introduce bpf_tcp_ops.{enqueue,dequeue}_rcvq().
Date: Fri, 25 Sep 2026 00:04:53 +0000	[thread overview]
Message-ID: <DLNYI40PF2Q3.1KYC8MHZU2VJ@gmail.com> (raw)
In-Reply-To: <20260923213719.224838-4-kuniyu@google.com>

On Wed, Sep 23, 2026 at 09:35 PM Kuniyuki Iwashima <kuniyu@google.com> wrote:
> +	/* Call bpf when the TCP stack enqueues/dequeues payload
> +	 * to/from sk->sk_receive_queue.
> +	 *
> +	 * Only bpf_tcp_ops is supported.
> +	 *
> +	 * It can be used to adjust sk->sk_rcvlowat and suppress
> +	 * unnecessary wakeups before sufficient data is available.
> +	 */
> +	BPF_SOCK_OPS_RCVQ_CB_FLAG = (1<<7),
>  /* Mask of all currently supported cb flags */
> -	BPF_SOCK_OPS_ALL_CB_FLAGS       = 0x7F,
> +	BPF_SOCK_OPS_ALL_CB_FLAGS       = 0xFF,

can we drop the flag ?
hdr_opt_len() is called for every tx skb without per-socket opt-in.
The prog in patch 8 already returns when the socket has no
sk_storage.

The flag is one bit per socket shared by all bpf_tcp_ops in the
cgroup hierarchy. When one prog clears it the others stop getting
enqueue_rcvq().

Then sk_is_mptcp() check in the kfunc is enough and there is no need
to touch bpf_sock_ops_cb_flags_set() and TCP_BPF_SOCK_OPS_CB_FLAGS.

  parent reply	other threads:[~2026-09-25  0:04 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-09-23 21:35 [PATCH v2 bpf-next 0/8] bpf: Add bpf_tcp_ops hooks for TCP AutoLOWAT Kuniyuki Iwashima
2026-09-23 21:35 ` [PATCH v2 bpf-next 1/8] bpf: tcp: Convert deny-list for bpf_{get,set}sockopt() to allow-list Kuniyuki Iwashima
2026-09-23 22:04   ` Emil Tsalapatis
2026-09-23 22:31   ` bot+bpf-ci
2026-09-24 15:53   ` Stanislav Fomichev
2026-09-23 21:35 ` [PATCH v2 bpf-next 2/8] selftest: bpf: Use BPF_SOCK_OPS_ALL_CB_FLAGS + 1 for bad_cb_test_rv Kuniyuki Iwashima
2026-09-23 22:11   ` Emil Tsalapatis
2026-09-23 21:35 ` [PATCH v2 bpf-next 3/8] bpf: tcp: Introduce bpf_tcp_ops.{enqueue,dequeue}_rcvq() Kuniyuki Iwashima
2026-09-23 21:50   ` sashiko-bot
2026-09-23 22:42   ` Emil Tsalapatis
2026-09-25  0:04   ` Alexei Starovoitov [this message]
2026-09-25  0:39     ` Kuniyuki Iwashima
2026-09-25  1:41       ` Alexei Starovoitov
2026-09-25 17:33         ` Amery Hung
2026-09-27  0:18           ` Kuniyuki Iwashima
2026-09-30 19:56             ` Amery Hung
2026-09-30 21:03               ` Kuniyuki Iwashima
2026-09-23 21:35 ` [PATCH v2 bpf-next 4/8] bpf: tcp: Support bpf_sock_ops_cb_flags_set() for bpf_tcp_ops Kuniyuki Iwashima
2026-09-23 22:31   ` bot+bpf-ci
2026-09-23 21:35 ` [PATCH v2 bpf-next 5/8] tcp: Split out __tcp_set_rcvlowat() Kuniyuki Iwashima
2026-09-24  3:39   ` Emil Tsalapatis
2026-09-23 21:35 ` [PATCH v2 bpf-next 6/8] bpf: mptcp: Don't support BPF_SOCK_OPS_RCVQ_CB_FLAG Kuniyuki Iwashima
2026-09-24  3:48   ` Emil Tsalapatis
2026-09-24  4:10     ` Kuniyuki Iwashima
2026-09-23 21:35 ` [PATCH v2 bpf-next 7/8] bpf: tcp: Add kfunc to adjust sk->sk_rcvlowat Kuniyuki Iwashima
2026-09-23 22:02   ` sashiko-bot
2026-09-23 22:21     ` Kuniyuki Iwashima
2026-09-24  0:30   ` Emil Tsalapatis
2026-09-23 21:35 ` [PATCH v2 bpf-next 8/8] selftest: bpf: Add test for bpf_tcp_ops.{enqueue,dequeue}_rcvq() Kuniyuki Iwashima

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=DLNYI40PF2Q3.1KYC8MHZU2VJ@gmail.com \
    --to=alexei.starovoitov@gmail.com \
    --cc=andrii@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=cleger@meta.com \
    --cc=daniel@iogearbox.net \
    --cc=eddyz87@gmail.com \
    --cc=edumazet@google.com \
    --cc=john.fastabend@gmail.com \
    --cc=kuni1840@gmail.com \
    --cc=kuniyu@google.com \
    --cc=martin.lau@linux.dev \
    --cc=memxor@gmail.com \
    --cc=ncardwell@google.com \
    --cc=netdev@vger.kernel.org \
    --cc=sdf@fomichev.me \
    --cc=ukyab@berkeley.edu \
    --cc=willemb@google.com \
    --cc=yonghong.song@linux.dev \
    /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