From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CAD84C433DF for ; Tue, 7 Jul 2020 15:24:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A7481207D0 for ; Tue, 7 Jul 2020 15:24:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594135472; bh=8HfJxiaBhyuUcN47TRW9Cdd12Anjqh3d9fdQtGgxGGE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=DBDz6v8cK7o1XLyOqQXgmz67dASK1KtrIONCicYKH7zFVHVGhvXZytLQxW/jNICVy GGd6eiezQyV0Isk/LcnID+15+xI5WEFMHGNZfQNPNYh+XKF3dSIkEuaowKCGxofCiL mqGm132lLuFQhNv/t+XiJRmVJO62F/T2MbfBtIQM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730100AbgGGPY3 (ORCPT ); Tue, 7 Jul 2020 11:24:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:37886 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728878AbgGGPYU (ORCPT ); Tue, 7 Jul 2020 11:24:20 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 41D3A2078D; Tue, 7 Jul 2020 15:24:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594135459; bh=8HfJxiaBhyuUcN47TRW9Cdd12Anjqh3d9fdQtGgxGGE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GcgiBGkYGz8pQLlc18S6xrZRTND6CpFgF4KHYj06QaavvCOxNZr5LCcIlzxartLu2 2mJVqNbBRKZVypWgfZ+egi7RLwwlnUIc0mk/lgm0HRc0BpB+iWnw+mX1hAGJmNH1Nz Ap2h9JZ994tE7hTPRbUERppGu0smPyXEmu4PrvyA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Howells , Sasha Levin Subject: [PATCH 5.7 049/112] rxrpc: Fix afs large storage transmission performance drop Date: Tue, 7 Jul 2020 17:16:54 +0200 Message-Id: <20200707145803.337562856@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200707145800.925304888@linuxfoundation.org> References: <20200707145800.925304888@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: David Howells [ Upstream commit 02c28dffb13abbaaedece1e4a6493b48ad3f913a ] Commit 2ad6691d988c, which moved the modification of the status annotation for a packet in the Tx buffer prior to the retransmission moved the state clearance, but managed to lose the bit that set it to UNACK. Consequently, if a retransmission occurs, the packet is accidentally changed to the ACK state (ie. 0) by masking it off, which means that the packet isn't counted towards the tally of newly-ACK'd packets if it gets hard-ACK'd. This then prevents the congestion control algorithm from recovering properly. Fix by reinstating the change of state to UNACK. Spotted by the generic/460 xfstest. Fixes: 2ad6691d988c ("rxrpc: Fix race between incoming ACK parser and retransmitter") Signed-off-by: David Howells Signed-off-by: Sasha Levin --- net/rxrpc/call_event.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c index 985fb89202d0c..9ff85ee8337cd 100644 --- a/net/rxrpc/call_event.c +++ b/net/rxrpc/call_event.c @@ -253,7 +253,7 @@ static void rxrpc_resend(struct rxrpc_call *call, unsigned long now_j) * confuse things */ annotation &= ~RXRPC_TX_ANNO_MASK; - annotation |= RXRPC_TX_ANNO_RESENT; + annotation |= RXRPC_TX_ANNO_UNACK | RXRPC_TX_ANNO_RESENT; call->rxtx_annotations[ix] = annotation; skb = call->rxtx_buffer[ix]; -- 2.25.1