From patchwork Mon Nov 28 17:04:00 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13057819 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B10A8C4332F for ; Mon, 28 Nov 2022 17:05:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232851AbiK1RFz (ORCPT ); Mon, 28 Nov 2022 12:05:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49038 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232856AbiK1RFS (ORCPT ); Mon, 28 Nov 2022 12:05:18 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 023E7F0E for ; Mon, 28 Nov 2022 09:04:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1669655047; 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; bh=SvA60jdErhXDl3kEW9qJtabgGVPEkbYeDoN+XXDo72Y=; b=eZDIh9ur+4q0LUrsI6HXiUOsZvA6QMRx8JMNnb1gswCiy+1VhXX6/cktazKYHH4XNF+pH7 1nYICono96IMoYpNbfKY5FpZic6g4sy2mvLdmn1SuQS0faMFmoERTyqV0vXSsST4jS04d2 2HbVQ5GEk6n3Djiue1RSUslICHYwBAU= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-93-Phzg0pRoOU65DlIsu7g6AA-1; Mon, 28 Nov 2022 12:04:03 -0500 X-MC-Unique: Phzg0pRoOU65DlIsu7g6AA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 55ADF1C07547; Mon, 28 Nov 2022 17:04:03 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.14]) by smtp.corp.redhat.com (Postfix) with ESMTP id A9A3E1731B; Mon, 28 Nov 2022 17:04:02 +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] afs: Fix fileserver probe RTT handling From: David Howells To: marc.dionne@auristor.com Cc: dhowells@redhat.com, linux-afs@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Mon, 28 Nov 2022 17:04:00 +0000 Message-ID: <166965503999.3392585.13954054113218099395.stgit@warthog.procyon.org.uk> User-Agent: StGit/1.5 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org The fileserver probing code attempts to work out the best fileserver to use for a volume by retrieving the RTT calculated by AF_RXRPC for the probe call sent to each server and comparing them. Sometimes, however, no RTT estimate is available and rxrpc_kernel_get_srtt() returns false, leading good fileservers to be given an RTT of UINT_MAX and thus causing the rotation algorithm to ignore them. Fix afs_select_fileserver() to ignore rxrpc_kernel_get_srtt()'s return value and just take the estimated RTT it provides - which will be capped at 1 second. Fixes: 1d4adfaf6574 ("rxrpc: Make rxrpc_kernel_get_srtt() indicate validity") Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org --- fs/afs/fs_probe.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/afs/fs_probe.c b/fs/afs/fs_probe.c index c0031a3ab42f..3ac5fcf98d0d 100644 --- a/fs/afs/fs_probe.c +++ b/fs/afs/fs_probe.c @@ -167,8 +167,8 @@ void afs_fileserver_probe_result(struct afs_call *call) clear_bit(AFS_SERVER_FL_HAS_FS64, &server->flags); } - if (rxrpc_kernel_get_srtt(call->net->socket, call->rxcall, &rtt_us) && - rtt_us < server->probe.rtt) { + rxrpc_kernel_get_srtt(call->net->socket, call->rxcall, &rtt_us); + if (rtt_us < server->probe.rtt) { server->probe.rtt = rtt_us; server->rtt = rtt_us; alist->preferred = index;