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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,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 4CF64C43381 for ; Mon, 18 Mar 2019 09:40:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1BC952075C for ; Mon, 18 Mar 2019 09:40:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552902049; bh=vZziSGpGjuq7EcDtYDJvNMZrSXCU9weoJlzObpLLZb8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=LiDvPjgeo+2lEOExw9cyO5xvHhiSYzUCKxj8bj9ok0H0BoiCTGRHd7gs0E+boaClV 81dc8D3jziy+v9V8r0oZeisG39weD0lD0avg3vJEgBekQpHZmHAp9x/eTW3ptNWRVo nyFfeu2hJATVebrG46EJdMo+pm+6i/ORx0wAJUpg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728735AbfCRJee (ORCPT ); Mon, 18 Mar 2019 05:34:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:42974 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728720AbfCRJed (ORCPT ); Mon, 18 Mar 2019 05:34:33 -0400 Received: from localhost (5356596B.cm-6-7b.dynamic.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 4A1332083D; Mon, 18 Mar 2019 09:34:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552901672; bh=vZziSGpGjuq7EcDtYDJvNMZrSXCU9weoJlzObpLLZb8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rjCSpwDE8KTc6Bl9xte4iK675Hi7sJY8NULV4QlOkfXQ64wmiXu1kwYyfBuTV8SQS 8YJo0kAzn6PUVzpBTypM6dzupcnHpZjzCurTSy2nGbMLIEzydqtkTje+E1o2i2PP1L 8+xk0YpXOFrPl9tSZVUHoYHJ5rp84nxMNiTNNHtM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Howells , Marc Dionne , "David S. Miller" Subject: [PATCH 4.14 14/34] rxrpc: Fix client call queueing, waiting for channel Date: Mon, 18 Mar 2019 10:25:38 +0100 Message-Id: <20190318084146.644842685@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190318084144.657740413@linuxfoundation.org> References: <20190318084144.657740413@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Howells [ Upstream commit 69ffaebb90369ce08657b5aea4896777b9d6e8fc ] rxrpc_get_client_conn() adds a new call to the front of the waiting_calls queue if the connection it's going to use already exists. This is bad as it allows calls to get starved out. Fix this by adding to the tail instead. Also change the other enqueue point in the same function to put it on the front (ie. when we have a new connection). This makes the point that in the case of a new connection the new call goes at the front (though it doesn't actually matter since the queue should be unoccupied). Fixes: 45025bceef17 ("rxrpc: Improve management and caching of client connection objects") Signed-off-by: David Howells Reviewed-by: Marc Dionne Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/rxrpc/conn_client.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/net/rxrpc/conn_client.c +++ b/net/rxrpc/conn_client.c @@ -351,7 +351,7 @@ static int rxrpc_get_client_conn(struct * normally have to take channel_lock but we do this before anyone else * can see the connection. */ - list_add_tail(&call->chan_wait_link, &candidate->waiting_calls); + list_add(&call->chan_wait_link, &candidate->waiting_calls); if (cp->exclusive) { call->conn = candidate; @@ -430,7 +430,7 @@ found_extant_conn: call->conn = conn; call->security_ix = conn->security_ix; call->service_id = conn->service_id; - list_add(&call->chan_wait_link, &conn->waiting_calls); + list_add_tail(&call->chan_wait_link, &conn->waiting_calls); spin_unlock(&conn->channel_lock); _leave(" = 0 [extant %d]", conn->debug_id); return 0;