From patchwork Mon Mar 17 12:03:13 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Xing X-Patchwork-Id: 14019121 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-pl1-f175.google.com (mail-pl1-f175.google.com [209.85.214.175]) (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 D1B4C19DF64 for ; Mon, 17 Mar 2025 12:03:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.175 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742213005; cv=none; b=ameNsZoppcvLDDf19WJitNwwhjRNrm2rxxom0HnaB+4ueUyG5brXvbsMpiCH5K9rCDrLy3Fif5LTMoyqHEgE8i8VtEmQdPCClxlBf0eWxMGQwGwN+WXUBZUHoSUFB8Ngts/UMLIpPAY1JMt0l07VkjvJfqnuGmRgC2h4Nbl7B7g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742213005; c=relaxed/simple; bh=tvKt0IBQOFOscCPgNvBzBW3C0jSt8n0TRBcclRCWTgQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=gEt4ZIfenBgCYK8AmPGW6b84Po3zCelqJGSeguoJ973WNfdPBe4RzRp+uOjvapWCEphXz4uf2EnAprA5zv0L3C29Wv55gCccovouJunIwU0Bh49VvH5vCFKGQkjb7IJy0c39tF7R34DVTvhUZO38DNSN/8hlLkb6YlYT7uVTeKU= 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=RFNoo1/1; arc=none smtp.client-ip=209.85.214.175 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="RFNoo1/1" Received: by mail-pl1-f175.google.com with SMTP id d9443c01a7336-22401f4d35aso76606175ad.2 for ; Mon, 17 Mar 2025 05:03:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1742213003; x=1742817803; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Kf6DxGuSScGEoN+1w6aBjA7f/gOaQi5M3ePcErz6rUs=; b=RFNoo1/1r5LEDoI8EeyJG4vjMDw4PoWZ87nlLNskvWwsB+If+mf+IGGVOIh2is5pPT sgIb48xnvfT3Y0PK3cibIKUDoLuKtbOvi9c5zApbu6bAEz5I3UTLu6G0tjjbJLu5dBjZ 7nqb/30XcvXahW+Ntv5QMsEWap5RJ3CgPAoPtx2bZTvRhLCZwPCR2LV3xzYXshUz5uCf G7YGp/8TBgDhvQdOi3muDsklH36swE/I74wGpr6aESrIT5chQ+cyfLqHLEQ/MZEMRxfm /XNovVTbv+dcdhlEtUrAuzfj4dk9nC/v1k6Q4Q44w0xx/0qUN6wz5oweAR7e3lAQOx5q AKOw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1742213003; x=1742817803; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Kf6DxGuSScGEoN+1w6aBjA7f/gOaQi5M3ePcErz6rUs=; b=hKnYtNYoziGVx1DcMCLr4ZnYJoITYDrU95qWxFgQzzpnuHiX8XwA2D1sWPR7EthrS3 xfv36LkTwgVZN2OiPrUDISfqw3k4TqI5IZOqDIWlN5iAoFopPz53UHTsASOAIOk7VfY+ IMeqRdzJvHlnzJvMlPjDxVhW6mvyGyIaQ/lL22uqGsRv6QZeWz8/KG9jlBQh0Q1lBPHi DGqcR0joIVc4/Z/vxpSQ9NxsF69lNfO1M7S4NEihRjoWYzCoDFQzIyW/CC0qRVgKL4Ih wRYYagllHMA628rSZfVCyWEI9nIpMyGPdVYngP1QJLlsZZGr6dT+5h1IiswPR4GLH5t2 28gw== X-Gm-Message-State: AOJu0YzRQumqKG0sMxzvV8FO/1GhPFK82taaPcrE+4B2SQsvy009bSHD 1Ju29njEjvMsFI/kwKiGL25xFiK0kKcreFJxUEPQQBXvuzgRdBoY X-Gm-Gg: ASbGnctVFgHZQH5bKZDoyrvmZF7MLIfoQuFpXYRtVYB8N/93EibGpVHssD7Ksy3xmmx 3cq4+thbgrGHsZssmESr8AOYPC1M2c//0D9uTEASy2JBsDxMAf2EV5QKewdBAyV5jn1Hw1Pxu1K HONxZvEcaGF6WYBDD4TLBbh2vnT1F/TVVzWjf2+DTgcvSiRl742ZQe/OPsxObgvzE0Azloq1Bbr pqdDJ4cY25zlO1FlLOXcfWKVpexa4xVBW9PlMbrNqRuE53Xi4/c1qQrTepy6w9s/ecmqxQx9p8I Nd50Ot2d92tgAU17IOcqo5Fyn9VPeeGzGuuyfZmZnpzC/cS9+mj1m1KmBtB29HUiSf036mRW9S7 EY2Rqb+frdyD/BD+B X-Google-Smtp-Source: AGHT+IGHROTMz5O7pgnhFkAxvrqNuivQeoNJNIxt8kazouZEN4X3OfyGHZUuDSgXobkv1EGJv9m8Ug== X-Received: by 2002:a17:902:d502:b0:224:1eaa:5de1 with SMTP id d9443c01a7336-225e0a4fd9cmr141278545ad.18.1742213002860; Mon, 17 Mar 2025 05:03:22 -0700 (PDT) Received: from KERNELXING-MB0.tencent.com ([43.132.141.24]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-225c6bd4e02sm73045835ad.226.2025.03.17.05.03.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 Mar 2025 05:03:22 -0700 (PDT) From: Jason Xing To: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, horms@kernel.org, ncardwell@google.com, kuniyu@amazon.com, dsahern@kernel.org Cc: netdev@vger.kernel.org, Jason Xing Subject: [PATCH net-next v4 1/2] tcp: support TCP_RTO_MIN_US for set/getsockopt use Date: Mon, 17 Mar 2025 20:03:13 +0800 Message-Id: <20250317120314.41404-2-kerneljasonxing@gmail.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20250317120314.41404-1-kerneljasonxing@gmail.com> References: <20250317120314.41404-1-kerneljasonxing@gmail.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org Support adjusting/reading RTO MIN for socket level by using set/getsockopt(). This new option has the same effect as TCP_BPF_RTO_MIN, which means it doesn't affect RTAX_RTO_MIN usage (by using ip route...). Considering that bpf option was implemented before this patch, so we need to use a standalone new option for pure tcp set/getsockopt() use. When the socket is created, its icsk_rto_min is set to the default value that is controlled by sysctl_tcp_rto_min_us. Then if application calls setsockopt() with TCP_RTO_MIN_US flag to pass a valid value, then icsk_rto_min will be overridden in jiffies unit. This patch adds WRITE_ONCE/READ_ONCE to avoid data-race around icsk_rto_min. Signed-off-by: Jason Xing --- Documentation/networking/ip-sysctl.rst | 4 ++-- include/net/tcp.h | 2 +- include/uapi/linux/tcp.h | 1 + net/ipv4/tcp.c | 13 ++++++++++++- 4 files changed, 16 insertions(+), 4 deletions(-) diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index 054561f8dcae..5c63ab928b97 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -1229,8 +1229,8 @@ tcp_pingpong_thresh - INTEGER tcp_rto_min_us - INTEGER Minimal TCP retransmission timeout (in microseconds). Note that the rto_min route option has the highest precedence for configuring this - setting, followed by the TCP_BPF_RTO_MIN socket option, followed by - this tcp_rto_min_us sysctl. + setting, followed by the TCP_BPF_RTO_MIN and TCP_RTO_MIN_US socket + options, followed by this tcp_rto_min_us sysctl. The recommended practice is to use a value less or equal to 200000 microseconds. diff --git a/include/net/tcp.h b/include/net/tcp.h index 7207c52b1fc9..6a7aab854b86 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -806,7 +806,7 @@ u32 tcp_delack_max(const struct sock *sk); static inline u32 tcp_rto_min(const struct sock *sk) { const struct dst_entry *dst = __sk_dst_get(sk); - u32 rto_min = inet_csk(sk)->icsk_rto_min; + u32 rto_min = READ_ONCE(inet_csk(sk)->icsk_rto_min); if (dst && dst_metric_locked(dst, RTAX_RTO_MIN)) rto_min = dst_metric_rtt(dst, RTAX_RTO_MIN); diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index 32a27b4a5020..b2476cf7058e 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -137,6 +137,7 @@ enum { #define TCP_IS_MPTCP 43 /* Is MPTCP being used? */ #define TCP_RTO_MAX_MS 44 /* max rto time in ms */ +#define TCP_RTO_MIN_US 45 /* min rto time in us */ #define TCP_REPAIR_ON 1 #define TCP_REPAIR_OFF 0 diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 46951e749308..b89c1b676b8e 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3352,7 +3352,7 @@ int tcp_disconnect(struct sock *sk, int flags) icsk->icsk_probes_out = 0; icsk->icsk_probes_tstamp = 0; icsk->icsk_rto = TCP_TIMEOUT_INIT; - icsk->icsk_rto_min = TCP_RTO_MIN; + WRITE_ONCE(icsk->icsk_rto_min, TCP_RTO_MIN); icsk->icsk_delack_max = TCP_DELACK_MAX; tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; tcp_snd_cwnd_set(tp, TCP_INIT_CWND); @@ -3833,6 +3833,14 @@ int do_tcp_setsockopt(struct sock *sk, int level, int optname, return -EINVAL; WRITE_ONCE(inet_csk(sk)->icsk_rto_max, msecs_to_jiffies(val)); return 0; + case TCP_RTO_MIN_US: { + int rto_min = usecs_to_jiffies(val); + + if (rto_min > TCP_RTO_MIN || rto_min < TCP_TIMEOUT_MIN) + return -EINVAL; + WRITE_ONCE(inet_csk(sk)->icsk_rto_min, rto_min); + return 0; + } } sockopt_lock_sock(sk); @@ -4672,6 +4680,9 @@ int do_tcp_getsockopt(struct sock *sk, int level, case TCP_RTO_MAX_MS: val = jiffies_to_msecs(tcp_rto_max(sk)); break; + case TCP_RTO_MIN_US: + val = jiffies_to_usecs(READ_ONCE(inet_csk(sk)->icsk_rto_min)); + break; default: return -ENOPROTOOPT; } From patchwork Mon Mar 17 12:03:14 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Xing X-Patchwork-Id: 14019122 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-pl1-f180.google.com (mail-pl1-f180.google.com [209.85.214.180]) (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 A7924238146 for ; Mon, 17 Mar 2025 12:03:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.180 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742213008; cv=none; b=adII2EHGD2A540Yet1VmxQjZp+bbquk3YElLniYUhGu5Z1eHbQ19tyIQgufZqAMxBhv+BBTvHEu051TcOL+nP3w2I9RoefcUtayvsnBDtDCar2hZJaadq6z6k78xGvgo9JuebXdl5R55V777C5hYu3EzjQE+K647LuM0ai5d8pM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742213008; c=relaxed/simple; bh=MHnizJDMJeBm/LrHcC8OCzYI37asgxjyeyvIUK03+/8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=VIfDgiAT5Ai/DEAqQC1FdKw3/ttAHmPw2Ux29p1X2jx+SH0HomEKcfAn0Z3fLx1DLDyxnwIdntNx4kP1QMSkHjHipaLjGsy20y3i6HGqvDnweGUPJlHh438Sea6PlA69mNXaaCk/NisXhj2gWn88sTGVvu/FgjreJWoRPD99s7k= 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=khXG73zo; arc=none smtp.client-ip=209.85.214.180 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="khXG73zo" Received: by mail-pl1-f180.google.com with SMTP id d9443c01a7336-22622ddcc35so5588535ad.2 for ; Mon, 17 Mar 2025 05:03:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1742213006; x=1742817806; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=s66STxKtwWxJhm+J05CzZyQ2UdqL5FlNUNwHDphGfrU=; b=khXG73zoVvddqxjko3y/Zl2C71Hok1hDmsoVELZDoS34qtpwQY16S1PkGJRIxTh5m+ Mr+X1H9gpRs5klfMkKhf0BdH4ZaPiUZMCINh2Zz4rUi5VHfoRJOBP6eQcIbjYwzHfY1w LX9/fU1OcW5bVACeK8mPHy2iZrKBzGsTF858ntsMkkumdIHS9BCAhYHPcFTqKkzjugq/ +hNRxb2eEfIOIu+aPgPM9+gMOTWgzEwuxMQJC5Gy+edTleYToQZC4JZpB2H8/ci/lkzE hH3VfMzVC4nTzxqEwescEpBnqUb+/iaTbnhH9ZKNz24m/V20xYtXMRFR+Ae2kZV4Q82A oMdA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1742213006; x=1742817806; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=s66STxKtwWxJhm+J05CzZyQ2UdqL5FlNUNwHDphGfrU=; b=a3xTiQkxBoJCrrT47OelI9K34QQIjTsW//FxV4K9SYhgLAOMJkBkA8CW1SYW72syBm fLxUJet/sMRhIvrn+KhGijkdBELMRXy/Ho0EM8abo1Wc7rXnobmAPLMq8OsxEQSzuZDq 4JhhGEsSxiJIgi6gg0/dQQtCI2BMXuSEqxqMC+I1sxUxYRbV1JMASouvuT1dmzVBjpU7 s10N8fIkSP1FS20kZFV8L2ZXwALFN2fkqVWgAqIRiUo7z3x5oBRpeTITWi1nOg3Nt2ns 8FHfqzktPOJLCrkU3zhYN3l8BqbuZdFXsv+UhXl/WFvgrU/T669LXrLd+3mk4iDzIWwG xFkA== X-Gm-Message-State: AOJu0Yxv2z9S9gbuG95MLUzzvf+GpLHtnv9fcclvlUfi/wrqJOUOJjZ9 UzuPHG/is1NxMMwcdqIZQ9BZNEJxCxHsXRZThitzd7tXiZX8/Drs X-Gm-Gg: ASbGncunJHPat7uOTzlEAcbJnWBoOQb4mQ2HdVC2cQBZI6SBRYrY1flOdwdQJwr0vZi 6X4C35LxI/IAtwdIpBiBBgSWBa1z2btCOBvP72jeT3pAMMxKL1iCFRMGH/OTSair3vVx6DGIjUR iTUjgTF28fiX1SnWIYDB9xLgL68yEJO3mBDRx4tVq64lYNP0XTl+jv9ul7mp+SAn5SEAPm9ZRBd LE9i7OMX8jPfYH5xqCqQ4NSy2olRB/JS28eXTaO1739vhcuz6EJMy6t/RfR4C5dvoaPLxKJmYpc vkqeQfU0yujnpd7SBGQRA5bjr3pGPBSmYLm5dQPWoH08M1wMCgZrEXk5Ji1Yr4g4Nd8ar58QbLs VLL3dnlYyRQAK+dpf X-Google-Smtp-Source: AGHT+IFMLJJOUdAvQn6WqpmarjOkICRRJxH0ekTkQZC7RNkkHRILtnuPRR/W1tdtHcVE4NMYeiPaCA== X-Received: by 2002:a17:902:da85:b0:224:910:23f0 with SMTP id d9443c01a7336-225e0b11989mr150714955ad.49.1742213005802; Mon, 17 Mar 2025 05:03:25 -0700 (PDT) Received: from KERNELXING-MB0.tencent.com ([43.132.141.24]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-225c6bd4e02sm73045835ad.226.2025.03.17.05.03.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 Mar 2025 05:03:25 -0700 (PDT) From: Jason Xing To: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, horms@kernel.org, ncardwell@google.com, kuniyu@amazon.com, dsahern@kernel.org Cc: netdev@vger.kernel.org, Jason Xing Subject: [PATCH net-next v4 2/2] tcp: support TCP_DELACK_MAX_US for set/getsockopt use Date: Mon, 17 Mar 2025 20:03:14 +0800 Message-Id: <20250317120314.41404-3-kerneljasonxing@gmail.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20250317120314.41404-1-kerneljasonxing@gmail.com> References: <20250317120314.41404-1-kerneljasonxing@gmail.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org Support adjusting/reading delayed ack max for socket level by using set/getsockopt(). This option aligns with TCP_BPF_DELACK_MAX usage. Considering that bpf option was implemented before this patch, so we need to use a standalone new option for pure tcp set/getsockopt() use. Add WRITE_ONCE/READ_ONCE() to prevent data-race if setsockopt() happens to write one value to icsk_delack_max while icsk_delack_max is being read. Signed-off-by: Jason Xing --- include/uapi/linux/tcp.h | 1 + net/ipv4/tcp.c | 13 ++++++++++++- net/ipv4/tcp_output.c | 2 +- 3 files changed, 14 insertions(+), 2 deletions(-) diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index b2476cf7058e..2377e22f2c4b 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -138,6 +138,7 @@ enum { #define TCP_IS_MPTCP 43 /* Is MPTCP being used? */ #define TCP_RTO_MAX_MS 44 /* max rto time in ms */ #define TCP_RTO_MIN_US 45 /* min rto time in us */ +#define TCP_DELACK_MAX_US 46 /* max delayed ack time in us */ #define TCP_REPAIR_ON 1 #define TCP_REPAIR_OFF 0 diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index b89c1b676b8e..578e79024955 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3353,7 +3353,7 @@ int tcp_disconnect(struct sock *sk, int flags) icsk->icsk_probes_tstamp = 0; icsk->icsk_rto = TCP_TIMEOUT_INIT; WRITE_ONCE(icsk->icsk_rto_min, TCP_RTO_MIN); - icsk->icsk_delack_max = TCP_DELACK_MAX; + WRITE_ONCE(icsk->icsk_delack_max, TCP_DELACK_MAX); tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; tcp_snd_cwnd_set(tp, TCP_INIT_CWND); tp->snd_cwnd_cnt = 0; @@ -3841,6 +3841,14 @@ int do_tcp_setsockopt(struct sock *sk, int level, int optname, WRITE_ONCE(inet_csk(sk)->icsk_rto_min, rto_min); return 0; } + case TCP_DELACK_MAX_US: { + int delack_max = usecs_to_jiffies(val); + + if (delack_max > TCP_DELACK_MAX || delack_max < TCP_TIMEOUT_MIN) + return -EINVAL; + WRITE_ONCE(inet_csk(sk)->icsk_delack_max, delack_max); + return 0; + } } sockopt_lock_sock(sk); @@ -4683,6 +4691,9 @@ int do_tcp_getsockopt(struct sock *sk, int level, case TCP_RTO_MIN_US: val = jiffies_to_usecs(READ_ONCE(inet_csk(sk)->icsk_rto_min)); break; + case TCP_DELACK_MAX_US: + val = jiffies_to_usecs(READ_ONCE(inet_csk(sk)->icsk_delack_max)); + break; default: return -ENOPROTOOPT; } diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 24e56bf96747..65aa26d65987 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -4179,7 +4179,7 @@ u32 tcp_delack_max(const struct sock *sk) { u32 delack_from_rto_min = max(tcp_rto_min(sk), 2) - 1; - return min(inet_csk(sk)->icsk_delack_max, delack_from_rto_min); + return min(READ_ONCE(inet_csk(sk)->icsk_delack_max), delack_from_rto_min); } /* Send out a delayed ack, the caller does the policy checking