From patchwork Thu Jun 18 07:50:35 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 1311927 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=i30QONqY; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 49nYyW1jpKz9sRf for ; Thu, 18 Jun 2020 17:50:43 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728280AbgFRHul (ORCPT ); Thu, 18 Jun 2020 03:50:41 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:53562 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728245AbgFRHul (ORCPT ); Thu, 18 Jun 2020 03:50:41 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592466640; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8mNDAD09ZF11gVKKLJQ7tphenyVSu5+EHhncfG5s2V8=; b=i30QONqYY+dk2yx/XsX0vvi1FfM9MIThEX+3VatL2RORJcX6XRKbPpabkUmCJvejYc4r/3 hvpylH8eWrjTRSsuupQZv+JFyJHHYClEU2wsJc9LdmU7kyGGZl9MQ6vfttAWnhL3HwkSyp IiW8b/JPZbLwQOacis2SFw1rWM+z358= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-41-5bX6ePhfN2KccolsBVOJlA-1; Thu, 18 Jun 2020 03:50:38 -0400 X-MC-Unique: 5bX6ePhfN2KccolsBVOJlA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 363C31800D42; Thu, 18 Jun 2020 07:50:37 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-114-66.rdu2.redhat.com [10.10.114.66]) by smtp.corp.redhat.com (Postfix) with ESMTP id 684D160BF3; Thu, 18 Jun 2020 07:50:36 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH net 3/3] rxrpc: Fix afs large storage transmission performance drop From: David Howells To: netdev@vger.kernel.org Cc: dhowells@redhat.com, linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org Date: Thu, 18 Jun 2020 08:50:35 +0100 Message-ID: <159246663560.1229328.1476552302291944463.stgit@warthog.procyon.org.uk> In-Reply-To: <159246661514.1229328.4419873299996950969.stgit@warthog.procyon.org.uk> References: <159246661514.1229328.4419873299996950969.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.22 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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 --- 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 aa1c8eee6557..6be2672a65ea 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];