From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 25C473C3C16 for ; Fri, 31 Jul 2026 11:49:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785498572; cv=none; b=NqhJSjaUXTJ0M7uQzi2tlRZBFRa9S0gi+fxq96kZMafHwbE0EhHK+l8pk2fIXOZANwjGI2ECh0E+Otna/2gKGATzr346OBHg0BPE1SMpfHGLLf/YvBbOChh0u+miuyAIc1PRNtV3kC1chHIzT0z9FZKH81lhIiVpVze1Y2IiHeE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785498572; c=relaxed/simple; bh=LieFTCR6JmG/EdtuQxfKvLw/py+JZdVlzcvZNr6+KVU=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=AubfaxzoAetzEAZ5UzqahyFyw5RmQ8JG+z3o0/m2PdGssflF7jiB2AExWn+XAyDO9Utq3w1m3coj5iPTPv9N8BHfeAM7D7jwNVNEY7q3Rj71YZO6UhqIWGseuOR3+Wl6XnR9cwrZmdr9dIJ9AHoXDgXpY6W08U50URfOqNdAz94= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ota82xCx; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ota82xCx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DEF531F000E9; Fri, 31 Jul 2026 11:49:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785498571; bh=h1vre6+I4pZvUi9mbW7mr0tFWS5+iHnwPCpKms/xHnA=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=ota82xCxXcGiSR5Y6qbjOO/+7bWK4/IMFgr776AGjdq7qaQHKp1w7p2rIFVMwT5zK BElmf/YnJforesm6SBzOIhmofEDQsUgEGafeaEP0/tLRuIO1pGktSK5JcEumh9O3HZ BcrbMI+U+JYME+Fsp0Dgw1Sx+xlcpd+Un2njkvx21qi3aSrE3iecDA4A9sP8qxwL/6 WFKF8bWNOMjfqzBld/LPvrGXIYFC9yvftZILv8m61+wnwcqKLsRQ0OxVo3O6qEDE8e pwJumK5Q4EgLPcbg/pSE89ku6x+oZb+Se6PP7wiluxFqS1VY4Q2BB81VIgajGGkdfH BC0ZTZAdmJHrA== From: sashiko-bot@kernel.org Subject: Re: [PATCH v6 net-next 1/1] tcp: Replace min_tso_segs() with tso_segs() CC callback Reply-To: sashiko-reviews@lists.linux.dev To: chia-yu.chang@nokia-bell-labs.com Cc: bpf@vger.kernel.org In-Reply-To: <20260730114919.658373-1-chia-yu.chang@nokia-bell-labs.com> References: <20260730114919.658373-1-chia-yu.chang@nokia-bell-labs.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 31 Jul 2026 11:49:30 +0000 Message-Id: <20260731114930.DEF531F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Thank you for your contribution! Sashiko AI review found 1 potential issue(= s) to consider: - [High] tcp_tso_autosize is not exported as a BPF kfunc, making it impossi= ble for custom BPF CC programs to utilize standard TSO autosizing. -- --- Patch [1]: [PATCH v6 net-next 1/1] tcp: Replace min_tso_segs() with tso= _segs() CC callback --- commit e9e6269217c20aef163ee8ebfb7cab71f918807f Author: Chia-Yu Chang tcp: Replace min_tso_segs() with tso_segs() CC callback This patch replaces the existing min_tso_segs() CC callback with a new tso_segs() callback. The new callback provides the explicit TSO segment number for each data burst, completely bypassing tcp_tso_autosize(). > diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c > index d7c1444b5e304..d9bda3a84f261 100644 > --- a/net/ipv4/tcp_output.c > +++ b/net/ipv4/tcp_output.c [ ... ] > @@ -2269,6 +2269,7 @@ static u32 tcp_tso_autosize(const struct sock *sk, = unsigned int mss_now, > =20 > return max_t(u32, bytes / mss_now, min_tso_segs); > } > +EXPORT_SYMBOL(tcp_tso_autosize); [Severity: High] Since BPF congestion control programs now need to compute the final TSO segments value, do they need access to tcp_tso_autosize() to retain standard autosizing? The commit exports tcp_tso_autosize for native kernel modules, but it appea= rs missing from the BTF kfuncs set (bpf_tcp_ca_check_kfunc_ids) in net/ipv4/bpf_tcp_ca.c: BTF_KFUNCS_START(bpf_tcp_ca_check_kfunc_ids) BTF_ID_FLAGS(func, tcp_reno_ssthresh) BTF_ID_FLAGS(func, tcp_reno_cong_avoid) ... BTF_KFUNCS_END(bpf_tcp_ca_check_kfunc_ids) Without being registered here, custom BPF CC programs cannot call tcp_tso_autosize(). This might prevent them from properly migrating to the new tso_segs callback if they want to retain standard TSO autosizing. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260730114919.6583= 73-1-chia-yu.chang@nokia-bell-labs.com?part=3D1