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 8367335CB6B for ; Fri, 28 Aug 2026 16:18:07 +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=1787933888; cv=none; b=VBrkU4RjFrCCYlxg0mMc7NrFF9yu+DzhICSj7ODmE2z2TEkMUtZygItxZXl7NzzakuPdLLoMCbwc5Je/YZuMBuVWZgt0PwBOhBSgy1ODD5Yn6rLXsDPxq6Nhx6Vn0a3RM6Ea71NY8MRkB+l6G8lkXcRnTL2UgNyDn05nEX8PI0I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787933888; c=relaxed/simple; bh=aq0RIZOA0Rm1iSojL4qVeXiKqTxXw6cRpM+5iAuLm5U=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=LQd8BECIY6ejXDvbCtuQw/UlfTrWlpKdBVm98Acn6yMeetB0PgwAqFyv1W0hx+kYWODK/Z/+UzJeJ0OPkbB5p6yzEvnXiVosAFs5Nocsc/Vdzb1jdJdUsfDPyPx1ifc/U+Er62M9vCEuMxNZZtsTyCsaaWxaOPK+oXLnukP8tOA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=f5COwgTa; 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="f5COwgTa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BB4441F00A3E; Fri, 28 Aug 2026 16:18:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787933887; bh=S6pI0ycjmUUXDD+U51XyrdkpwGc8BLyYx7TpfN8ajHo=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=f5COwgTaXyKx3pKDnwlxk2/E/V1gZ5GgorqKJBv0WCPZcnvY9qG4nq4uegD4O9S9X /+UfuT++VoyOZWv4arU0lY5N9ioyuUMikCT6KPFzQil8xE4QTDTvHkEgAlee+eTZD1 /qGviEUdXTZ5PnI4Q9KQ/YlgWL1/DXUYlG0VWJpJkG+x2CzlzunL/+YTIPQRY3+swD wkX+KUKmhJjO7zQRAQRKYPakVLfwkTLCXvAh34VoiwXnIEVDb009Dl4Qf6jsoklaWg J9TL/zNHTKxxygLggLZ6qiMYOtqLyDAk9xQLBL7Eny4w4dZHIuE/ZtF3Q1Vkrspoeb SQQCE8Q3iKMxA== From: Chuck Lever Date: Fri, 28 Aug 2026 12:17:56 -0400 Subject: [PATCH v2 4/7] SUNRPC: Mark connection-oriented transports on svc_xprt Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260828-duplicate-reply-cache-v2-4-25069e660a7b@kernel.org> References: <20260828-duplicate-reply-cache-v2-0-25069e660a7b@kernel.org> In-Reply-To: <20260828-duplicate-reply-cache-v2-0-25069e660a7b@kernel.org> To: Jeff Layton , NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey Cc: Rick Macklem , linux-nfs@vger.kernel.org, Chuck Lever X-Mailer: b4 0.16-dev-da966 X-Developer-Signature: v=1; a=openpgp-sha256; l=3279; i=cel@kernel.org; h=from:subject:message-id; bh=aq0RIZOA0Rm1iSojL4qVeXiKqTxXw6cRpM+5iAuLm5U=; b=owEBbQKS/ZANAwAKATNqszNvZn+XAcsmYgBqkbS6ktP3Yg4auH+EQf6G/rg9EE5jmhuuDmOei PaC+ABrb2eJAjMEAAEKAB0WIQQosuWwEobfJDzyPv4zarMzb2Z/lwUCapG0ugAKCRAzarMzb2Z/ l9s9EACO7xrBdI4SKGg0MnxB++46CXVkFIfHNt7Y/OvMYSeh4BlqJqv3Wrc6eAxJS6sffgh0HGq w2oWdPyAQkePPttVEGoyE0H5yxr3/A3m59ZigIEiWENZ5Jk3xdMs+of8L2xJtT2gTAJGE3IDOkh NB3Qg9iRnR7hzHho3xunhfmQNkS7YsuYSgij1WUOU0Y85t5g/oXa/uCdgGJPhgMrnEXS0pXXDJX U+oCtSFzDuZ/B78HTvkY/MMrZ2lZme2rjlB8fW703SJM8/D7cpB1PUaaNsEgv4lYqgHivvw/KH+ vU+om5OTWzX6G6751A1WGgSFU30J+KFv/3fgTdJ7qTnxTaxs6j4TKGZmUnPyX1JJcZ2kqim5VUF 25MSAdFV+7M1Lbvsa2Jedg4ujJeyPxk1Ysxo4jdZnIySJi2s3SSomHpXFh6yjmNwS6nWcuM7d/z 7g3in833q13ZOgRdtRw3KyUCo8oM28j1b/riRNZuR3tqnfSsQvmShkos6mvyKnpMTdtHH+ONdts JlQ7I1+1xwexf7ElhrpvjbCA7nTIxRQQ8sllIFKaxW8afIRF6H/0o5Se6hLvbiT968fLfgtXhpr e5P16HPi9s3A/noK3D6i95yvqYsnAXlUKMx/Boeo30XhfdEYHVnd0cLH+fxf7Etx8a6zLTA8cjp vftMljoltbqek3Q== X-Developer-Key: i=cel@kernel.org; a=openpgp; fpr=28B2E5B01286DF243CF23EFE336AB3336F667F97 A TCP or RDMA svc_xprt carries one client's request stream, delivered reliably and in order, so a later request on it indicates that earlier replies reached the client. A UDP svc_xprt is shared by every peer and offers no such signal. Add an XPT_ORDERED flag, set by the TCP and RDMA init paths and clear for UDP, so the NFSD duplicate reply cache can confine implied-ACK eviction to transports where the signal holds. The flag has a cost on svcrdma. handle_connect_req() zeroes the remote port in the DRC key so a cached reply survives a reconnect, and implied-ACK eviction can retire such an entry while the original connection is still up. TCP gives up the same thing whenever a client re-binds its reserved port, so this follows from the eviction policy rather than from RDMA. Signed-off-by: Chuck Lever --- include/linux/sunrpc/svc_xprt.h | 1 + include/trace/events/sunrpc.h | 1 + net/sunrpc/svcsock.c | 1 + net/sunrpc/xprtrdma/svc_rdma_transport.c | 1 + 4 files changed, 4 insertions(+) diff --git a/include/linux/sunrpc/svc_xprt.h b/include/linux/sunrpc/svc_xprt.h index 53ed073640a6..ebab18e403b2 100644 --- a/include/linux/sunrpc/svc_xprt.h +++ b/include/linux/sunrpc/svc_xprt.h @@ -99,6 +99,7 @@ enum { XPT_LOCAL, /* connection from loopback interface */ XPT_KILL_TEMP, /* call xpo_kill_temp_xprt before closing */ XPT_CONG_CTRL, /* has congestion control */ + XPT_ORDERED, /* connection-oriented, in-order delivery */ XPT_HANDSHAKE, /* xprt requests a handshake */ XPT_TLS_SESSION, /* transport-layer security established */ XPT_PEER_AUTH, /* peer has been authenticated */ diff --git a/include/trace/events/sunrpc.h b/include/trace/events/sunrpc.h index 180346e520ff..2154fbe69945 100644 --- a/include/trace/events/sunrpc.h +++ b/include/trace/events/sunrpc.h @@ -1931,6 +1931,7 @@ TRACE_EVENT(svc_stats_latency, svc_xprt_flag(LOCAL) \ svc_xprt_flag(KILL_TEMP) \ svc_xprt_flag(CONG_CTRL) \ + svc_xprt_flag(ORDERED) \ svc_xprt_flag(HANDSHAKE) \ svc_xprt_flag(TLS_SESSION) \ svc_xprt_flag(PEER_AUTH) \ diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 840bec53e1ee..97a592ddeb48 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -1486,6 +1486,7 @@ static bool svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv) return false; set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags); set_bit(XPT_CONG_CTRL, &svsk->sk_xprt.xpt_flags); + set_bit(XPT_ORDERED, &svsk->sk_xprt.xpt_flags); if (sk->sk_state == TCP_LISTEN) { strcpy(svsk->sk_xprt.xpt_remotebuf, "listener"); set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags); diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index fabdfd891a41..5d39fce231a3 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -218,6 +218,7 @@ static struct svcxprt_rdma *svc_rdma_create_xprt(struct svc_serv *serv, * transports are suitable here. */ set_bit(XPT_CONG_CTRL, &cma_xprt->sc_xprt.xpt_flags); + set_bit(XPT_ORDERED, &cma_xprt->sc_xprt.xpt_flags); return cma_xprt; } -- 2.55.0