From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from vtj.irix.systems (vtj.irix.systems [82.76.27.144]) (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 51FAE4DB56E; Thu, 15 Oct 2026 12:48:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=82.76.27.144 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792068519; cv=none; b=Q0tGomjRleqQYKDnF4Ra78/IUVlixLwZInpAN7rSUBouk9WpZYjBS8ol6nmE6htdSjWYT358/p7J9dey72gs44W18nkgaJfJ75baz+NnIWNbd+15LKpUrGZbpahEM6gfOZA/z55nObbNhPMeKh1pP9Zm8KLxnsZ/5/Ra3qs4gjU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792068519; c=relaxed/simple; bh=DDrhK6cEYuEdzKZnEYKqiGFrYjXfqUZpW/pOJWUAKV8=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=TpFEGZocSu6WykI/ilmTqv54AUkoeCUu5J0g4UAv2xDQuoC3I9XMGHDwel8lKHI7/dKTbC9ESgVLy2VnfPTA5zsj/TbWnJ35W3P2Upo2X0PFh60S2g1fqP3reE+ZbCBo33jDaDNwV4gQoRfuYkcJbIcZmh1sprsCft3a7z+td+c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=andrei-z.com; spf=pass smtp.mailfrom=andrei-z.com; dkim=pass (2048-bit key) header.d=andrei-z.com header.i=@andrei-z.com header.b=Rs9gAHcf; arc=none smtp.client-ip=82.76.27.144 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=andrei-z.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=andrei-z.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=andrei-z.com header.i=@andrei-z.com header.b="Rs9gAHcf" Received: from MAILGW-BIG.big.vtj.corp.irix.systems (localhost [127.0.0.1]) by vtj.irix.systems (Proxmox) with ESMTP id 586D111CE4; Thu, 15 Oct 2026 15:48:31 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=andrei-z.com; h= cc:cc:content-transfer-encoding:content-type:content-type:date :from:from:message-id:mime-version:reply-to:subject:subject:to :to; s=sig1; bh=pSfeGOpMpiprqEI4nj4NucY4gLurRa86KRjoIACsb70=; b= Rs9gAHcfqv35DWL9OfCJ8VX8UdAekcAS6HD5dMXMk+LNh+kVnd7hf9jYT8rFHlv6 sM1eRBc3gnMKFGHtOkECdmidAnDTHA8jY1tZKAgFnu/caHnRpFN154MpXcFz6eIx 48dmo11iXjjVZqaYlIFA9j0rAsXx10rBwkReYx3rPpTEQ6wFVgt1ubDPhqN3XjrT vQeYVkG1RlFvtJ+gkMBgJQGORx8581/MsyWvFPVI0VALLm7z09TiAwfuU/1mnOoK /70Z1ugC19L0qo16OhgVr7XUNY4P7S7yJYtq8V4giIHjhqV1wiS/MytchNQte4Q9 jo/1Uwze45k52mov/WxH8w== Received: from VTJ-MX.corp.irix.systems (unknown [10.57.36.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by vtj.irix.systems (Proxmox) with ESMTPS id D959711D40; Thu, 15 Oct 2026 15:48:30 +0300 (EEST) Received: from [10.89.11.73] (10.57.8.14) by VTJ-MX.corp.irix.systems (2a02:2f04:1:9c24::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.49; Thu, 15 Oct 2026 15:48:30 +0300 From: Andrei-Alexandru Bleortu To: Chuck Lever , Jeff Layton , NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey CC: Andrei-Alexandru Bleortu , , Subject: [PATCH 0/1] svcrdma: Post small Replies inline Date: Thu, 15 Oct 2026 15:48:29 +0300 Message-ID: <20261015124830.2963045-1-me@andrei-z.com> X-Mailer: git-send-email 2.56.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: VTJ-MX.corp.irix.systems (2a02:2f04:1:9c24::6) To VTJ-MX.corp.irix.systems (2a02:2f04:1:9c24::6) The server posts every Reply by reference, so the HCA reads it from host memory before transmitting. This patch asks for 256 bytes of inline data at QP creation and posts a small Reply with IB_SEND_INLINE when it is the only WR in its ib_post_send() call. If the device refuses, it asks for less. The commit message has the details and the measurements. The matching client change, "xprtrdma: Post small RPC Calls inline", is going to the NFS client maintainers on its own. The two do not depend on each other. It builds with W=1 on nfsd-testing without new warnings. I tested it on the nfsd-testing of 25 September, in a QEMU guest with rdma_rxe on a dummy netdev. The NFS client and server ran on the same host over RDMA, using NFSv3 and NFSv4.1. 8 MiB of 4 KiB O_DIRECT writes and reads, and 200 small files, compared equal on the client and in the exported file. 5529 Sends went inline and 4521 by reference. The latter include the READ replies, which follow their data in the same chain. I also made rxe refuse inline requests above a limit and report a chosen vendor ID. The data still compared equal in each case: vendor ID limit QP got Intel 216/101/48 216/101/48 bytes Alibaba 96 96 bytes rxe 101 96 bytes At 216 bytes 5329 Sends went inline; at 96 or 101 only 6 did, as most Replies in this test are larger. The guest kernel also carried the xprtrdma patch. I wrote this patch with an LLM coding assistant (Claude Code), which also drafted the commit message and ran the build and the VM test. Andrei-Alexandru Bleortu (1): svcrdma: Post small Replies inline include/linux/sunrpc/svc_rdma.h | 2 + net/sunrpc/xprtrdma/svc_rdma_sendto.c | 31 ++++++++++-- net/sunrpc/xprtrdma/svc_rdma_transport.c | 62 +++++++++++++++++++++++- 3 files changed, 90 insertions(+), 5 deletions(-) base-commit: 78c334bc5ae61d23ca1cc2e43079c620f1d40866 -- 2.56.0