From nobody Thu Dec 18 16:32:57 2025 Received: from out-183.mta0.migadu.com (out-183.mta0.migadu.com [91.218.175.183]) (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 1AFEB25A64A for ; Tue, 25 Mar 2025 14:47:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.183 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742914066; cv=none; b=cNXI1GmeJvwQAyd7wqEhNX1xl9hLVc9RyjFEUMeh+xHzEDSQMzoSOUp4OK9rHW+oD8Z66pascJQbG8UTVj5SFolQIEC/bXx5g+38ivGil6i7OxhH10R+wEWvi8u001NezNNuFoh6SqawYkYN7KdBocvO/gAh8MnOLwceMMPnqlM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742914066; c=relaxed/simple; bh=6tCgdCxUoslKrQ/ImEbkLjcgZlfYHCZbXA2Xtm38wu0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lYQAKGOFR/U6k8zoHvhhxDBnH3rEuMGx0bv6am8I8cK5EpV92qc2GPRhVHDChRHSegvIikM+oYsCZBd9zWRARoRORg6B6MuT+Px/AFy9GGuNtjjd0JunnULgRaEAvRfa5dKcb1KtuGfNcR4WZukt4H2ZCdPwM4AKS0QAYhqi8LU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=M0GQ80LD; arc=none smtp.client-ip=91.218.175.183 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="M0GQ80LD" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1742914062; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8xwJEyFiNpZJx3SaGRoYy6EGc/eXAk39jTVoaj7Yj4Y=; b=M0GQ80LDJ/lC/A+AKKrvato8INN3kffgFKiNBRLjChpIIGsxc7DiHprLhehJ9EqGT09p0r YLB21lNJ+5YNljlYUWPCVbklaEtJ99QzTa/83GKAOWDov5fpwRaecIRPZFu71YMTJ9VtFy PH/TIitAGXu1VoNfAMRTRi1BplbRJOc= From: Jiayuan Chen To: netdev@vger.kernel.org, edumazet@google.com Cc: linux-kernel@vger.kernel.org, kuniyu@amazon.com, davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com, horms@kernel.org, dsahern@kernel.org, ncardwell@google.com, mrpre@163.com, Jiayuan Chen Subject: [PATCH net-next v3 2/2] tcp: add LINUX_MIB_PAWS_TW_REJECTED counter Date: Tue, 25 Mar 2025 22:47:04 +0800 Message-ID: <20250325144704.14363-3-jiayuan.chen@linux.dev> In-Reply-To: <20250325144704.14363-1-jiayuan.chen@linux.dev> References: <20250325144704.14363-1-jiayuan.chen@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" When TCP is in TIME_WAIT state, PAWS verification uses LINUX_PAWSESTABREJECTED, which is ambiguous and cannot be distinguished from other PAWS verification processes. Moreover, when PAWS occurs in TIME_WAIT, we typically need to pay special attention to upstream network devices, so we added a new counter, like the existing PAWS_OLD_ACK one. Also we update the doc with previously missing PAWS_OLD_ACK. usage: ''' nstat -az | grep PAWSTimewait TcpExtPAWSTimewait 1 0.0 ''' Suggested-by: Eric Dumazet Signed-off-by: Jiayuan Chen --- Documentation/networking/net_cachelines/snmp.rst | 2 ++ include/net/dropreason-core.h | 1 + include/uapi/linux/snmp.h | 1 + net/ipv4/proc.c | 1 + net/ipv4/tcp_minisocks.c | 2 +- 5 files changed, 6 insertions(+), 1 deletion(-) diff --git a/Documentation/networking/net_cachelines/snmp.rst b/Documentati= on/networking/net_cachelines/snmp.rst index bc96efc92cf5..bd44b3eebbef 100644 --- a/Documentation/networking/net_cachelines/snmp.rst +++ b/Documentation/networking/net_cachelines/snmp.rst @@ -37,6 +37,8 @@ unsigned_long LINUX_MIB_TIMEWAITKILLED unsigned_long LINUX_MIB_PAWSACTIVEREJECTED unsigned_long LINUX_MIB_PAWSESTABREJECTED unsigned_long LINUX_MIB_TSECR_REJECTED +unsigned_long LINUX_MIB_PAWS_OLD_ACK +unsigned_long LINUX_MIB_PAWS_TW_REJECTED unsigned_long LINUX_MIB_DELAYEDACKLOST unsigned_long LINUX_MIB_LISTENOVERFLOWS unsigned_long LINUX_MIB_LISTENDROPS diff --git a/include/net/dropreason-core.h b/include/net/dropreason-core.h index 9701d7f936f6..bea77934a235 100644 --- a/include/net/dropreason-core.h +++ b/include/net/dropreason-core.h @@ -287,6 +287,7 @@ enum skb_drop_reason { /** * @SKB_DROP_REASON_TCP_RFC7323_TW_PAWS: PAWS check, socket is in * TIME_WAIT state. + * Corresponds to LINUX_MIB_PAWS_TW_REJECTED. */ SKB_DROP_REASON_TCP_RFC7323_TW_PAWS, /** diff --git a/include/uapi/linux/snmp.h b/include/uapi/linux/snmp.h index eb9fb776fdc3..cca7f7eb6e9c 100644 --- a/include/uapi/linux/snmp.h +++ b/include/uapi/linux/snmp.h @@ -188,6 +188,7 @@ enum LINUX_MIB_PAWSESTABREJECTED, /* PAWSEstabRejected */ LINUX_MIB_TSECRREJECTED, /* TSEcrRejected */ LINUX_MIB_PAWS_OLD_ACK, /* PAWSOldAck */ + LINUX_MIB_PAWS_TW_REJECTED, /* PAWSTimewait */ LINUX_MIB_DELAYEDACKS, /* DelayedACKs */ LINUX_MIB_DELAYEDACKLOCKED, /* DelayedACKLocked */ LINUX_MIB_DELAYEDACKLOST, /* DelayedACKLost */ diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c index 10cbeb76c274..ea2f01584379 100644 --- a/net/ipv4/proc.c +++ b/net/ipv4/proc.c @@ -191,6 +191,7 @@ static const struct snmp_mib snmp4_net_list[] =3D { SNMP_MIB_ITEM("PAWSEstab", LINUX_MIB_PAWSESTABREJECTED), SNMP_MIB_ITEM("TSEcrRejected", LINUX_MIB_TSECRREJECTED), SNMP_MIB_ITEM("PAWSOldAck", LINUX_MIB_PAWS_OLD_ACK), + SNMP_MIB_ITEM("PAWSTimewait", LINUX_MIB_PAWS_TW_REJECTED), SNMP_MIB_ITEM("DelayedACKs", LINUX_MIB_DELAYEDACKS), SNMP_MIB_ITEM("DelayedACKLocked", LINUX_MIB_DELAYEDACKLOCKED), SNMP_MIB_ITEM("DelayedACKLost", LINUX_MIB_DELAYEDACKLOST), diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index 27511bf58c0f..43d7852ce07e 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -248,7 +248,7 @@ tcp_timewait_state_process(struct inet_timewait_sock *t= w, struct sk_buff *skb, =20 if (paws_reject) { *drop_reason =3D SKB_DROP_REASON_TCP_RFC7323_TW_PAWS; - __NET_INC_STATS(twsk_net(tw), LINUX_MIB_PAWSESTABREJECTED); + __NET_INC_STATS(twsk_net(tw), LINUX_MIB_PAWS_TW_REJECTED); } =20 if (!th->rst) { --=20 2.47.1