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=-5.7 required=3.0 tests=DATE_IN_PAST_03_06, DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, 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 E97ECC2D0DB for ; Wed, 22 Jan 2020 13:24:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BE17C2468D for ; Wed, 22 Jan 2020 13:24:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579699494; bh=1YzfcHjs92uvAFnhEsI/u9hRXryDJjS0n+AS3ZKt7l4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=OUNoV56vnsPzArd1yOau/2PM8wjK8UGp676Uu2rMXdxSck4LJwU9aAKT4IEnV5beW EWIm1+XKgUGqY2PaxF5nkioWhh4c8h/xP1eDGJYA8CojYwX5Eq2YOH1Wlt7PEbuM3C eHFnr3HPpSswL4rVgGQfLgxthcHg2bWc/N1lAzfw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731078AbgAVNYx (ORCPT ); Wed, 22 Jan 2020 08:24:53 -0500 Received: from mail.kernel.org ([198.145.29.99]:44166 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730589AbgAVNYv (ORCPT ); Wed, 22 Jan 2020 08:24:51 -0500 Received: from localhost (unknown [84.241.205.26]) (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 0D6D424697; Wed, 22 Jan 2020 13:24:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579699490; bh=1YzfcHjs92uvAFnhEsI/u9hRXryDJjS0n+AS3ZKt7l4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=afGH3CTAh4hIVJUmOnkCLubYuv9uOU3kl4pTQ5gh6XYhiaCTizAKAEzuwJKm4oRm6 CbHiDREuGTtXtvK2w3A8NgtZLyLY+meTgLMITMQRyGeUfSw5bHose5sXkW+VdZaVgc Dg4mtRycxo6vxCWQ1KWazedNQmjaCaGWqz5BG0Lg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Petr Machata , Jiri Pirko , Ido Schimmel , "David S. Miller" Subject: [PATCH 5.4 162/222] mlxsw: spectrum: Wipe xstats.backlog of down ports Date: Wed, 22 Jan 2020 10:29:08 +0100 Message-Id: <20200122092845.313521947@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200122092833.339495161@linuxfoundation.org> References: <20200122092833.339495161@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: Petr Machata commit ca7609ff3680c51d6c29897f3117aa2ad904f92a upstream. Per-port counter cache used by Qdiscs is updated periodically, unless the port is down. The fact that the cache is not updated for down ports is no problem for most counters, which are relative in nature. However, backlog is absolute in nature, and if there is a non-zero value in the cache around the time that the port goes down, that value just stays there. This value then leaks to offloaded Qdiscs that report non-zero backlog even if there (obviously) is no traffic. The HW does not keep backlog of a downed port, so do likewise: as the port goes down, wipe the backlog value from xstats. Fixes: 075ab8adaf4e ("mlxsw: spectrum: Collect tclass related stats periodically") Signed-off-by: Petr Machata Acked-by: Jiri Pirko Signed-off-by: Ido Schimmel Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/mellanox/mlxsw/spectrum.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c @@ -1161,6 +1161,9 @@ static void update_stats_cache(struct wo periodic_hw_stats.update_dw.work); if (!netif_carrier_ok(mlxsw_sp_port->dev)) + /* Note: mlxsw_sp_port_down_wipe_counters() clears the cache as + * necessary when port goes down. + */ goto out; mlxsw_sp_port_get_hw_stats(mlxsw_sp_port->dev, @@ -4170,6 +4173,15 @@ static int mlxsw_sp_port_unsplit(struct return 0; } +static void +mlxsw_sp_port_down_wipe_counters(struct mlxsw_sp_port *mlxsw_sp_port) +{ + int i; + + for (i = 0; i < TC_MAX_QUEUE; i++) + mlxsw_sp_port->periodic_hw_stats.xstats.backlog[i] = 0; +} + static void mlxsw_sp_pude_event_func(const struct mlxsw_reg_info *reg, char *pude_pl, void *priv) { @@ -4191,6 +4203,7 @@ static void mlxsw_sp_pude_event_func(con } else { netdev_info(mlxsw_sp_port->dev, "link down\n"); netif_carrier_off(mlxsw_sp_port->dev); + mlxsw_sp_port_down_wipe_counters(mlxsw_sp_port); } }