From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f176.google.com (mail-pl1-f176.google.com [209.85.214.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7EEC523815C; Fri, 30 May 2025 20:07:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.176 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748635672; cv=none; b=pnRrLUiPH/AZz11ft3g8kr4YS7aMkGF0mT/vUGie6DAIbFidPiI5IhOr6y1mLfZFUgz1/ps6GQYQtoibWPpeI354KS8iCIkoJlrphl8EU+y/x5HSELZhUxoFlAjgK8r47zER4bOYpgElnqYdjr9VaPxvQ3kcokuCYnt4OxNXcjM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748635672; c=relaxed/simple; bh=ct6SQwoevQtBGTGnt34VdrBpbpGOKC4SFkv6MHopodI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QtHBKV66XXy0JBpkhssazu7yP8BtnKzBZHHPQ3sXDIkOV+BEySg0x6wCJEy6I/gSVJAI4UvdJuHDj+JULrzxukl0rtFg4PXc9Wg/fZQ/ZWS7duzEoGYKSITckCNEsdRxuIpKGN+O1wY4Xeu44mfoxpuJCYa+gA7Ufz8qeigKubo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=Nniwo4Mi; arc=none smtp.client-ip=209.85.214.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Nniwo4Mi" Received: by mail-pl1-f176.google.com with SMTP id d9443c01a7336-22c33677183so21430235ad.2; Fri, 30 May 2025 13:07:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1748635670; x=1749240470; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=3qrAgajVEjl6XH/LWK60rQI6fj3/gwI++K2zKdM+P6M=; b=Nniwo4MiTz1vHtWo8xk629bk72iPsCDfh2DIzGCFOEm7o7oJWBSpePBgCVKyH6iMRU R1kpp9XE9Km48zvkgZlc9YlZhnAW469UYO2PbrZSGXEurDU++qxz4Am3Wftt0M9kH18z /pv+w+Ufs4h/43RnxZWUW9zlbpIm3PWoaSRY1jba4azUa3rUWGjtGr+6nHq93++pDbXh rSc9pqG175kBYyMP3lZ2ve/sMGTqOGV8bDrGpWCS3CaVaQpaSrxrjRvFW+ch+U0PY9RI wlKmHOYFISOjXJ8Plv5gQeTOGm39rdNfHucj1zcVeo7X6jYOylkpsnZZNrsBHrCqmA4v OrHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1748635670; x=1749240470; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=3qrAgajVEjl6XH/LWK60rQI6fj3/gwI++K2zKdM+P6M=; b=fv+iEbGM2uqmSADfoUjJUAbqdDJGZt1IDM85O0xmTtJwBrrs2KLVk8rAXJW6Cu9wNl NPP4LU9ahp6FB5H8C/aikNfHRxdDkz1cwGzJD+pyAaXtEX/73Bu0cE6XzFXB3veIjGVv l6hqAh7LFcf0WWPzXIezDlb/pQZKBJk+GmcgyFT2h27FSkpgwh1eytwWMb6KcuQPzcpw jZD/+kBb6WQzjuDO4n8Iw2APL6zwjbW+HXzyjhDSSTSEzo11vxBKuGvyxuSlppq+da1k yHGXows8QI7aso4von/kR+wn5Bp1n4bJDY6vf4gcfH2vA5ZC5FvixI7l5K67ZRwnksEd CGBg== X-Forwarded-Encrypted: i=1; AJvYcCUkBjRgu3WyWGeB05/MoprjpYJ50W7dgqgTizqBf2v69H+3v8GAfqYlKIX7tyKhWuMK9hk=@vger.kernel.org X-Gm-Message-State: AOJu0Yw3bETX2I0P2HvVdCEJXQ2lTJtunO7SkkMsJfq1KxBf9jVlfcis cMLGnh9CMUv5sekGAx05coZLBZrzulbsz5GZwWMISw1HyJB5cAZ54lU48ERCx1jG X-Gm-Gg: ASbGnctGducuXCAG7lnPDukBLaXKLrU/dyCjp7vuAN9oAoSS6EhH0eIqq0oBqd3DPZ4 iLPrRAGbYpKA7BoWndr9k2gsv98zi6YoHlfWo1g0WItlpKtt5WiULl7rhEek9lTlCfAuhCQSWd/ k4LfQnSSN6Pd9DLTpXoD0YUIIpeWE+2GgQAoWE5RFXXqCedamlAteejkFmooseGn54mNhAwWP0o mK6QYZuWcRsKCvXPGK9nzV0iXbNxval8RSLBG6n2K5ieRaNc0gMtYoRxQIoxoPZJnfzfRkV6GEq QlOuBGrKDrtBCZsDY/VlSrd40pnDQil4DDk0O7iRVb1uhX+r7B9f2kngZEWwTCs= X-Google-Smtp-Source: AGHT+IExqgS+QiIQaRgj6w2lMgt6QAD99sUUI7RmE+T/GB4UUMprWxGVBVKpKwR+Nz7Wap5PPwNzrg== X-Received: by 2002:a17:902:f54a:b0:234:d292:be84 with SMTP id d9443c01a7336-23538ed9508mr54534975ad.10.1748635669584; Fri, 30 May 2025 13:07:49 -0700 (PDT) Received: from gmail.com ([98.97.39.137]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-23506d14cb0sm32114995ad.218.2025.05.30.13.07.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 30 May 2025 13:07:49 -0700 (PDT) Date: Fri, 30 May 2025 13:07:35 -0700 From: John Fastabend To: Cong Wang Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, zhoufeng.zf@bytedance.com, jakub@cloudflare.com, zijianzhang@bytedance.com, Amery Hung , Cong Wang Subject: Re: [Patch bpf-next v3 4/4] tcp_bpf: improve ingress redirection performance with message corking Message-ID: <20250530200735.hhzeicomnb7mbwdl@gmail.com> References: <20250519203628.203596-1-xiyou.wangcong@gmail.com> <20250519203628.203596-5-xiyou.wangcong@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250519203628.203596-5-xiyou.wangcong@gmail.com> On 2025-05-19 13:36:28, Cong Wang wrote: > From: Zijian Zhang > > The TCP_BPF ingress redirection path currently lacks the message corking > mechanism found in standard TCP. This causes the sender to wake up the > receiver for every message, even when messages are small, resulting in > reduced throughput compared to regular TCP in certain scenarios. > > This change introduces a kernel worker-based intermediate layer to provide > automatic message corking for TCP_BPF. While this adds a slight latency > overhead, it significantly improves overall throughput by reducing > unnecessary wake-ups and reducing the sock lock contention. > > Reviewed-by: Amery Hung > Co-developed-by: Cong Wang > Signed-off-by: Cong Wang > Signed-off-by: Zijian Zhang > --- > include/linux/skmsg.h | 19 ++++ > net/core/skmsg.c | 139 ++++++++++++++++++++++++++++- > net/ipv4/tcp_bpf.c | 197 ++++++++++++++++++++++++++++++++++++++++-- > 3 files changed, 347 insertions(+), 8 deletions(-) [...] > + /* At this point, the data has been handled well. If one of the > + * following conditions is met, we can notify the peer socket in > + * the context of this system call immediately. > + * 1. If the write buffer has been used up; > + * 2. Or, the message size is larger than TCP_BPF_GSO_SIZE; > + * 3. Or, the ingress queue was empty; > + * 4. Or, the tcp socket is set to no_delay. > + * Otherwise, kick off the backlog work so that we can have some > + * time to wait for any incoming messages before sending a > + * notification to the peer socket. > + */ OK this series looks like it should work to me. See one small comment below. Also from the perf numbers in the cover letter is the latency difference reduced/removed if the socket is set to no_delay? > + nonagle = tcp_sk(sk)->nonagle; > + if (!sk_stream_memory_free(sk) || > + tot_size >= TCP_BPF_GSO_SIZE || ingress_msg_empty || > + (!(nonagle & TCP_NAGLE_CORK) && (nonagle & TCP_NAGLE_OFF))) { > + release_sock(sk); > + psock->backlog_work_delayed = false; > + sk_psock_backlog_msg(psock); > + lock_sock(sk); > + } else { > + sk_psock_run_backlog_work(psock, false); > + } > + > +error: > + sk_psock_put(sk_redir, psock); > + return ret; > +} > + > static int tcp_bpf_send_verdict(struct sock *sk, struct sk_psock *psock, > struct sk_msg *msg, int *copied, int flags) > { > @@ -442,18 +619,24 @@ static int tcp_bpf_send_verdict(struct sock *sk, struct sk_psock *psock, > cork = true; > psock->cork = NULL; > } > - release_sock(sk); > > - origsize = msg->sg.size; > - ret = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress, > - msg, tosend, flags); > - sent = origsize - msg->sg.size; > + if (redir_ingress) { > + ret = tcp_bpf_ingress_backlog(sk, sk_redir, msg, tosend); > + } else { > + release_sock(sk); > + > + origsize = msg->sg.size; > + ret = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress, > + msg, tosend, flags); nit, we can drop redir ingress at this point from tcp_bpf_sendmsg_redir? It no longer handles ingress? A follow up patch would probably be fine. > + sent = origsize - msg->sg.size; > + > + lock_sock(sk); > + sk_mem_uncharge(sk, sent); > + } > > if (eval == __SK_REDIRECT) > sock_put(sk_redir); Thanks.