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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7F41EC32774 for ; Tue, 23 Aug 2022 09:13:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347335AbiHWJL4 (ORCPT ); Tue, 23 Aug 2022 05:11:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39192 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348206AbiHWJJ5 (ORCPT ); Tue, 23 Aug 2022 05:09:57 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1DC8B74DD6; Tue, 23 Aug 2022 01:30:52 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id AC5D8614CA; Tue, 23 Aug 2022 08:29:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B60ADC433B5; Tue, 23 Aug 2022 08:29:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1661243367; bh=TwqLt3hNn9yFWoN1IQ77dG1SLU8ADuZswLmHKbLb61w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gVKNRmVHoQYeCVWeHwmWYI9CPl2hVG9TcfCrBrmtIQJ/RziwEY26enWN4Zgs3uzpd dsKKh077qRDRiqR+hdvMrs7etBY07XMQLbmGFlR60Kn5m7nzY3GdDCH74jsrUt7dbx C7kcBra7r2jKDBfAXepoRFa/DUWenHti/mK3t5C4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vladimir Oltean , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.19 254/365] net: mscc: ocelot: report ndo_get_stats64 from the wraparound-resistant ocelot->stats Date: Tue, 23 Aug 2022 10:02:35 +0200 Message-Id: <20220823080128.824469865@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220823080118.128342613@linuxfoundation.org> References: <20220823080118.128342613@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vladimir Oltean [ Upstream commit e780e3193e889fd8358b862f7cd18ec5a4901caf ] Rather than reading the stats64 counters directly from the 32-bit hardware, it's better to rely on the output produced by the periodic ocelot_port_update_stats(). It would be even better to call ocelot_port_update_stats() right from ocelot_get_stats64() to make sure we report the current values rather than the ones from 2 seconds ago. But we need to export ocelot_port_update_stats() from the switch lib towards the switchdev driver for that, and future work will largely undo that. There are more ocelot-based drivers waiting to be introduced, an example of which is the SPI-controlled VSC7512. In that driver's case, it will be impossible to call ocelot_port_update_stats() from ndo_get_stats64 context, since the latter is atomic, and reading the stats over SPI is sleepable. So the compromise taken here, which will also hold going forward, is to report 64-bit counters to stats64, which are not 100% up to date. Fixes: a556c76adc05 ("net: mscc: Add initial Ocelot switch support") Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/mscc/ocelot_net.c | 53 +++++++++++++------------- 1 file changed, 26 insertions(+), 27 deletions(-) diff --git a/drivers/net/ethernet/mscc/ocelot_net.c b/drivers/net/ethernet/mscc/ocelot_net.c index 6b9d37138844..330d30841cdc 100644 --- a/drivers/net/ethernet/mscc/ocelot_net.c +++ b/drivers/net/ethernet/mscc/ocelot_net.c @@ -725,41 +725,40 @@ static void ocelot_get_stats64(struct net_device *dev, struct ocelot_port_private *priv = netdev_priv(dev); struct ocelot *ocelot = priv->port.ocelot; int port = priv->port.index; + u64 *s; spin_lock(&ocelot->stats_lock); - /* Configure the port to read the stats from */ - ocelot_write(ocelot, SYS_STAT_CFG_STAT_VIEW(port), - SYS_STAT_CFG); + s = &ocelot->stats[port * OCELOT_NUM_STATS]; /* Get Rx stats */ - stats->rx_bytes = ocelot_read(ocelot, SYS_COUNT_RX_OCTETS); - stats->rx_packets = ocelot_read(ocelot, SYS_COUNT_RX_SHORTS) + - ocelot_read(ocelot, SYS_COUNT_RX_FRAGMENTS) + - ocelot_read(ocelot, SYS_COUNT_RX_JABBERS) + - ocelot_read(ocelot, SYS_COUNT_RX_LONGS) + - ocelot_read(ocelot, SYS_COUNT_RX_64) + - ocelot_read(ocelot, SYS_COUNT_RX_65_127) + - ocelot_read(ocelot, SYS_COUNT_RX_128_255) + - ocelot_read(ocelot, SYS_COUNT_RX_256_511) + - ocelot_read(ocelot, SYS_COUNT_RX_512_1023) + - ocelot_read(ocelot, SYS_COUNT_RX_1024_1526) + - ocelot_read(ocelot, SYS_COUNT_RX_1527_MAX); - stats->multicast = ocelot_read(ocelot, SYS_COUNT_RX_MULTICAST); + stats->rx_bytes = s[OCELOT_STAT_RX_OCTETS]; + stats->rx_packets = s[OCELOT_STAT_RX_SHORTS] + + s[OCELOT_STAT_RX_FRAGMENTS] + + s[OCELOT_STAT_RX_JABBERS] + + s[OCELOT_STAT_RX_LONGS] + + s[OCELOT_STAT_RX_64] + + s[OCELOT_STAT_RX_65_127] + + s[OCELOT_STAT_RX_128_255] + + s[OCELOT_STAT_RX_256_511] + + s[OCELOT_STAT_RX_512_1023] + + s[OCELOT_STAT_RX_1024_1526] + + s[OCELOT_STAT_RX_1527_MAX]; + stats->multicast = s[OCELOT_STAT_RX_MULTICAST]; stats->rx_dropped = dev->stats.rx_dropped; /* Get Tx stats */ - stats->tx_bytes = ocelot_read(ocelot, SYS_COUNT_TX_OCTETS); - stats->tx_packets = ocelot_read(ocelot, SYS_COUNT_TX_64) + - ocelot_read(ocelot, SYS_COUNT_TX_65_127) + - ocelot_read(ocelot, SYS_COUNT_TX_128_255) + - ocelot_read(ocelot, SYS_COUNT_TX_256_511) + - ocelot_read(ocelot, SYS_COUNT_TX_512_1023) + - ocelot_read(ocelot, SYS_COUNT_TX_1024_1526) + - ocelot_read(ocelot, SYS_COUNT_TX_1527_MAX); - stats->tx_dropped = ocelot_read(ocelot, SYS_COUNT_TX_DROPS) + - ocelot_read(ocelot, SYS_COUNT_TX_AGING); - stats->collisions = ocelot_read(ocelot, SYS_COUNT_TX_COLLISION); + stats->tx_bytes = s[OCELOT_STAT_TX_OCTETS]; + stats->tx_packets = s[OCELOT_STAT_TX_64] + + s[OCELOT_STAT_TX_65_127] + + s[OCELOT_STAT_TX_128_255] + + s[OCELOT_STAT_TX_256_511] + + s[OCELOT_STAT_TX_512_1023] + + s[OCELOT_STAT_TX_1024_1526] + + s[OCELOT_STAT_TX_1527_MAX]; + stats->tx_dropped = s[OCELOT_STAT_TX_DROPS] + + s[OCELOT_STAT_TX_AGED]; + stats->collisions = s[OCELOT_STAT_TX_COLLISION]; spin_unlock(&ocelot->stats_lock); } -- 2.35.1