From patchwork Thu Sep 30 07:59:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiaoliang Yang X-Patchwork-Id: 12527595 X-Patchwork-Delegate: kuba@kernel.org 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7BF8CC433EF for ; Thu, 30 Sep 2021 07:50:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 586F66142A for ; Thu, 30 Sep 2021 07:50:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348843AbhI3Hv6 (ORCPT ); Thu, 30 Sep 2021 03:51:58 -0400 Received: from inva021.nxp.com ([92.121.34.21]:36982 "EHLO inva021.nxp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348701AbhI3Hv5 (ORCPT ); Thu, 30 Sep 2021 03:51:57 -0400 Received: from inva021.nxp.com (localhost [127.0.0.1]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id 9C4892022E3; Thu, 30 Sep 2021 09:50:13 +0200 (CEST) Received: from aprdc01srsp001v.ap-rdc01.nxp.com (aprdc01srsp001v.ap-rdc01.nxp.com [165.114.16.16]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id 37C882017C0; Thu, 30 Sep 2021 09:50:13 +0200 (CEST) Received: from localhost.localdomain (mega.ap.freescale.net [10.192.208.232]) by aprdc01srsp001v.ap-rdc01.nxp.com (Postfix) with ESMTP id 7EBE7183AC89; Thu, 30 Sep 2021 15:50:10 +0800 (+08) From: Xiaoliang Yang To: davem@davemloft.net, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Cc: allan.nielsen@microchip.com, joergen.andreasen@microchip.com, UNGLinuxDriver@microchip.com, vinicius.gomes@intel.com, michael.chan@broadcom.com, vishal@chelsio.com, saeedm@mellanox.com, jiri@mellanox.com, idosch@mellanox.com, alexandre.belloni@bootlin.com, kuba@kernel.org, xiaoliang.yang_1@nxp.com, po.liu@nxp.com, vladimir.oltean@nxp.com, leoyang.li@nxp.com, f.fainelli@gmail.com, andrew@lunn.ch, vivien.didelot@gmail.com, claudiu.manoil@nxp.com, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org, matthias.bgg@gmail.com, horatiu.vultur@microchip.com Subject: [PATCH v6 net-next 1/8] net: mscc: ocelot: serialize access to the MAC table Date: Thu, 30 Sep 2021 15:59:41 +0800 Message-Id: <20210930075948.36981-2-xiaoliang.yang_1@nxp.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210930075948.36981-1-xiaoliang.yang_1@nxp.com> References: <20210930075948.36981-1-xiaoliang.yang_1@nxp.com> X-Virus-Scanned: ClamAV using ClamSMTP Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Vladimir Oltean DSA would like to remove the rtnl_lock from its SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE handlers, and the felix driver uses the same MAC table functions as ocelot. This means that the MAC table functions will no longer be implicitly serialized with respect to each other by the rtnl_mutex, we need to add a dedicated lock in ocelot for the non-atomic operations of selecting a MAC table row, reading/writing what we want and polling for completion. Signed-off-by: Vladimir Oltean Signed-off-by: Xiaoliang Yang --- drivers/net/ethernet/mscc/ocelot.c | 53 +++++++++++++++++++++++------- include/soc/mscc/ocelot.h | 3 ++ 2 files changed, 44 insertions(+), 12 deletions(-) diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c index 559177e6ded4..61ac49751230 100644 --- a/drivers/net/ethernet/mscc/ocelot.c +++ b/drivers/net/ethernet/mscc/ocelot.c @@ -20,11 +20,13 @@ struct ocelot_mact_entry { enum macaccess_entry_type type; }; +/* Must be called with &ocelot->mact_lock held */ static inline u32 ocelot_mact_read_macaccess(struct ocelot *ocelot) { return ocelot_read(ocelot, ANA_TABLES_MACACCESS); } +/* Must be called with &ocelot->mact_lock held */ static inline int ocelot_mact_wait_for_completion(struct ocelot *ocelot) { u32 val; @@ -36,6 +38,7 @@ static inline int ocelot_mact_wait_for_completion(struct ocelot *ocelot) TABLE_UPDATE_SLEEP_US, TABLE_UPDATE_TIMEOUT_US); } +/* Must be called with &ocelot->mact_lock held */ static void ocelot_mact_select(struct ocelot *ocelot, const unsigned char mac[ETH_ALEN], unsigned int vid) @@ -67,6 +70,7 @@ int ocelot_mact_learn(struct ocelot *ocelot, int port, ANA_TABLES_MACACCESS_ENTRYTYPE(type) | ANA_TABLES_MACACCESS_MAC_TABLE_CMD(MACACCESS_CMD_LEARN); unsigned int mc_ports; + int err; /* Set MAC_CPU_COPY if the CPU port is used by a multicast entry */ if (type == ENTRYTYPE_MACv4) @@ -79,18 +83,28 @@ int ocelot_mact_learn(struct ocelot *ocelot, int port, if (mc_ports & BIT(ocelot->num_phys_ports)) cmd |= ANA_TABLES_MACACCESS_MAC_CPU_COPY; + mutex_lock(&ocelot->mact_lock); + ocelot_mact_select(ocelot, mac, vid); /* Issue a write command */ ocelot_write(ocelot, cmd, ANA_TABLES_MACACCESS); - return ocelot_mact_wait_for_completion(ocelot); + err = ocelot_mact_wait_for_completion(ocelot); + + mutex_unlock(&ocelot->mact_lock); + + return err; } EXPORT_SYMBOL(ocelot_mact_learn); int ocelot_mact_forget(struct ocelot *ocelot, const unsigned char mac[ETH_ALEN], unsigned int vid) { + int err; + + mutex_lock(&ocelot->mact_lock); + ocelot_mact_select(ocelot, mac, vid); /* Issue a forget command */ @@ -98,7 +112,11 @@ int ocelot_mact_forget(struct ocelot *ocelot, ANA_TABLES_MACACCESS_MAC_TABLE_CMD(MACACCESS_CMD_FORGET), ANA_TABLES_MACACCESS); - return ocelot_mact_wait_for_completion(ocelot); + err = ocelot_mact_wait_for_completion(ocelot); + + mutex_unlock(&ocelot->mact_lock); + + return err; } EXPORT_SYMBOL(ocelot_mact_forget); @@ -114,7 +132,9 @@ static void ocelot_mact_init(struct ocelot *ocelot) | ANA_AGENCTRL_LEARN_IGNORE_VLAN, ANA_AGENCTRL); - /* Clear the MAC table */ + /* Clear the MAC table. We are not concurrent with anyone, so + * holding &ocelot->mact_lock is pointless. + */ ocelot_write(ocelot, MACACCESS_CMD_INIT, ANA_TABLES_MACACCESS); } @@ -1018,6 +1038,7 @@ int ocelot_port_fdb_do_dump(const unsigned char *addr, u16 vid, } EXPORT_SYMBOL(ocelot_port_fdb_do_dump); +/* Must be called with &ocelot->mact_lock held */ static int ocelot_mact_read(struct ocelot *ocelot, int port, int row, int col, struct ocelot_mact_entry *entry) { @@ -1068,33 +1089,40 @@ static int ocelot_mact_read(struct ocelot *ocelot, int port, int row, int col, int ocelot_fdb_dump(struct ocelot *ocelot, int port, dsa_fdb_dump_cb_t *cb, void *data) { + int err = 0; int i, j; + /* We could take the lock just around ocelot_mact_read, but doing so + * thousands of times in a row seems rather pointless and inefficient. + */ + mutex_lock(&ocelot->mact_lock); + /* Loop through all the mac tables entries. */ for (i = 0; i < ocelot->num_mact_rows; i++) { for (j = 0; j < 4; j++) { struct ocelot_mact_entry entry; bool is_static; - int ret; - ret = ocelot_mact_read(ocelot, port, i, j, &entry); + err = ocelot_mact_read(ocelot, port, i, j, &entry); /* If the entry is invalid (wrong port, invalid...), * skip it. */ - if (ret == -EINVAL) + if (err == -EINVAL) continue; - else if (ret) - return ret; + else if (err) + break; is_static = (entry.type == ENTRYTYPE_LOCKED); - ret = cb(entry.mac, entry.vid, is_static, data); - if (ret) - return ret; + err = cb(entry.mac, entry.vid, is_static, data); + if (err) + break; } } - return 0; + mutex_unlock(&ocelot->mact_lock); + + return err; } EXPORT_SYMBOL(ocelot_fdb_dump); @@ -2080,6 +2108,7 @@ int ocelot_init(struct ocelot *ocelot) mutex_init(&ocelot->stats_lock); mutex_init(&ocelot->ptp_lock); + mutex_init(&ocelot->mact_lock); spin_lock_init(&ocelot->ptp_clock_lock); snprintf(queue_name, sizeof(queue_name), "%s-stats", dev_name(ocelot->dev)); diff --git a/include/soc/mscc/ocelot.h b/include/soc/mscc/ocelot.h index 06706a9fd5b1..682cd058096c 100644 --- a/include/soc/mscc/ocelot.h +++ b/include/soc/mscc/ocelot.h @@ -674,6 +674,9 @@ struct ocelot { struct delayed_work stats_work; struct workqueue_struct *stats_queue; + /* Lock for serializing access to the MAC table */ + struct mutex mact_lock; + struct workqueue_struct *owq; u8 ptp:1;