From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id AF945431BB; Fri, 20 Oct 2023 12:11:03 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id F018E4069D; Fri, 20 Oct 2023 12:10:59 +0200 (CEST) Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by mails.dpdk.org (Postfix) with ESMTP id CB1E240284 for ; Fri, 20 Oct 2023 12:10:57 +0200 (CEST) Received: from dggpeml100024.china.huawei.com (unknown [172.30.72.55]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4SBgHM48xhzVlmZ; Fri, 20 Oct 2023 18:07:11 +0800 (CST) Received: from localhost.localdomain (10.50.163.32) by dggpeml100024.china.huawei.com (7.185.36.115) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Fri, 20 Oct 2023 18:10:54 +0800 From: Chengwen Feng To: , , , , Andrew Rybchenko , Somnath Kotur , Kalesh AP CC: , Subject: [PATCH v2 1/7] ethdev: fix race-condition of proactive error handling mode Date: Fri, 20 Oct 2023 10:07:40 +0000 Message-ID: <20231020100746.31520-2-fengchengwen@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20231020100746.31520-1-fengchengwen@huawei.com> References: <20230301030610.49468-1-fengchengwen@huawei.com> <20231020100746.31520-1-fengchengwen@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.50.163.32] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpeml100024.china.huawei.com (7.185.36.115) X-CFilter-Loop: Reflected X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org In the proactive error handling mode, the PMD will set the data path pointers to dummy functions and then try recovery, in this period the application may still invoking data path API. This will introduce a race-condition with data path which may lead to crash [1]. Although the PMD added delay after setting data path pointers to cover the above race-condition, it reduces the probability, but it doesn't solve the problem. To solve the race-condition problem fundamentally, the following requirements are added: 1. The PMD should set the data path pointers to dummy functions after report RTE_ETH_EVENT_ERR_RECOVERING event. 2. The application should stop data path API invocation when process the RTE_ETH_EVENT_ERR_RECOVERING event. 3. The PMD should set the data path pointers to valid functions before report RTE_ETH_EVENT_RECOVERY_SUCCESS event. 4. The application should enable data path API invocation when process the RTE_ETH_EVENT_RECOVERY_SUCCESS event. Also, this patch introduce a driver internal function rte_eth_fp_ops_setup which used as an help function for PMD. [1] http://patchwork.dpdk.org/project/dpdk/patch/20230220060839.1267349-2-ashok.k.kaladi@intel.com/ Fixes: eb0d471a8941 ("ethdev: add proactive error handling mode") Cc: stable@dpdk.org Signed-off-by: Chengwen Feng Acked-by: Konstantin Ananyev --- doc/guides/prog_guide/poll_mode_drv.rst | 20 +++++++--------- lib/ethdev/ethdev_driver.c | 8 +++++++ lib/ethdev/ethdev_driver.h | 10 ++++++++ lib/ethdev/rte_ethdev.h | 32 +++++++++++++++---------- lib/ethdev/version.map | 1 + 5 files changed, 46 insertions(+), 25 deletions(-) diff --git a/doc/guides/prog_guide/poll_mode_drv.rst b/doc/guides/prog_guide/poll_mode_drv.rst index c145a9066c..e380ff135a 100644 --- a/doc/guides/prog_guide/poll_mode_drv.rst +++ b/doc/guides/prog_guide/poll_mode_drv.rst @@ -638,14 +638,9 @@ different from the application invokes recovery in PASSIVE mode, the PMD automatically recovers from error in PROACTIVE mode, and only a small amount of work is required for the application. -During error detection and automatic recovery, -the PMD sets the data path pointers to dummy functions -(which will prevent the crash), -and also make sure the control path operations fail with a return code ``-EBUSY``. - -Because the PMD recovers automatically, -the application can only sense that the data flow is disconnected for a while -and the control API returns an error in this period. +During error detection and automatic recovery, the PMD sets the data path +pointers to dummy functions and also make sure the control path operations +failed with a return code ``-EBUSY``. In order to sense the error happening/recovering, as well as to restore some additional configuration, @@ -653,9 +648,9 @@ three events are available: ``RTE_ETH_EVENT_ERR_RECOVERING`` Notify the application that an error is detected - and the recovery is being started. + and the recovery is about to start. Upon receiving the event, the application should not invoke - any control path function until receiving + any control and data path API until receiving ``RTE_ETH_EVENT_RECOVERY_SUCCESS`` or ``RTE_ETH_EVENT_RECOVERY_FAILED`` event. .. note:: @@ -666,8 +661,9 @@ three events are available: ``RTE_ETH_EVENT_RECOVERY_SUCCESS`` Notify the application that the recovery from error is successful, - the PMD already re-configures the port, - and the effect is the same as a restart operation. + the PMD already re-configures the port. + The application should restore some additional configuration, and then + enable data path API invocation. ``RTE_ETH_EVENT_RECOVERY_FAILED`` Notify the application that the recovery from error failed, diff --git a/lib/ethdev/ethdev_driver.c b/lib/ethdev/ethdev_driver.c index fff4b7b4cd..65ead7b910 100644 --- a/lib/ethdev/ethdev_driver.c +++ b/lib/ethdev/ethdev_driver.c @@ -537,6 +537,14 @@ rte_eth_dma_zone_free(const struct rte_eth_dev *dev, const char *ring_name, return rc; } +void +rte_eth_fp_ops_setup(struct rte_eth_dev *dev) +{ + if (dev == NULL) + return; + eth_dev_fp_ops_setup(rte_eth_fp_ops + dev->data->port_id, dev); +} + const struct rte_memzone * rte_eth_dma_zone_reserve(const struct rte_eth_dev *dev, const char *ring_name, uint16_t queue_id, size_t size, unsigned int align, diff --git a/lib/ethdev/ethdev_driver.h b/lib/ethdev/ethdev_driver.h index deb23ada18..8567b96f53 100644 --- a/lib/ethdev/ethdev_driver.h +++ b/lib/ethdev/ethdev_driver.h @@ -1636,6 +1636,16 @@ int rte_eth_dma_zone_free(const struct rte_eth_dev *eth_dev, const char *name, uint16_t queue_id); +/** + * @internal + * Setup eth fast-path API to ethdev values. + * + * @param dev + * Pointer to struct rte_eth_dev. + */ +__rte_internal +void rte_eth_fp_ops_setup(struct rte_eth_dev *dev); + /** * @internal * Atomically set the link status for the specific device. diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h index 85b9af7a02..dbe2d9c745 100644 --- a/lib/ethdev/rte_ethdev.h +++ b/lib/ethdev/rte_ethdev.h @@ -3994,25 +3994,28 @@ enum rte_eth_event_type { */ RTE_ETH_EVENT_RX_AVAIL_THRESH, /** Port recovering from a hardware or firmware error. - * If PMD supports proactive error recovery, - * it should trigger this event to notify application - * that it detected an error and the recovery is being started. - * Upon receiving the event, the application should not invoke any control path API - * (such as rte_eth_dev_configure/rte_eth_dev_stop...) until receiving - * RTE_ETH_EVENT_RECOVERY_SUCCESS or RTE_ETH_EVENT_RECOVERY_FAILED event. - * The PMD will set the data path pointers to dummy functions, - * and re-set the data path pointers to non-dummy functions - * before reporting RTE_ETH_EVENT_RECOVERY_SUCCESS event. - * It means that the application cannot send or receive any packets - * during this period. + * + * If PMD supports proactive error recovery, it should trigger this + * event to notify application that it detected an error and the + * recovery is about to start. + * + * Upon receiving the event, the application should not invoke any + * control and data path API until receiving + * RTE_ETH_EVENT_RECOVERY_SUCCESS or RTE_ETH_EVENT_RECOVERY_FAILED + * event. + * + * Once this event is reported, the PMD will set the data path pointers + * to dummy functions, and re-set the data path pointers to valid + * functions before reporting RTE_ETH_EVENT_RECOVERY_SUCCESS event. + * * @note Before the PMD reports the recovery result, * the PMD may report the RTE_ETH_EVENT_ERR_RECOVERING event again, * because a larger error may occur during the recovery. */ RTE_ETH_EVENT_ERR_RECOVERING, /** Port recovers successfully from the error. - * The PMD already re-configured the port, - * and the effect is the same as a restart operation. + * + * The PMD already re-configured the port: * a) The following operation will be retained: (alphabetically) * - DCB configuration * - FEC configuration @@ -4039,6 +4042,9 @@ enum rte_eth_event_type { * (@see RTE_ETH_DEV_CAPA_FLOW_SHARED_OBJECT_KEEP) * c) Any other configuration will not be stored * and will need to be re-configured. + * + * The application should restore some additional configuration + * (see above case b/c), and then enable data path API invocation. */ RTE_ETH_EVENT_RECOVERY_SUCCESS, /** Port recovery failed. diff --git a/lib/ethdev/version.map b/lib/ethdev/version.map index 919ba5b8e6..1e6ee0a6f1 100644 --- a/lib/ethdev/version.map +++ b/lib/ethdev/version.map @@ -338,6 +338,7 @@ INTERNAL { rte_eth_devices; rte_eth_dma_zone_free; rte_eth_dma_zone_reserve; + rte_eth_fp_ops_setup; rte_eth_hairpin_queue_peer_bind; rte_eth_hairpin_queue_peer_unbind; rte_eth_hairpin_queue_peer_update; -- 2.17.1