From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by dpdk.org (Postfix) with ESMTP id E130F100C for ; Wed, 8 Aug 2018 09:00:06 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Aug 2018 00:00:02 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,456,1526367600"; d="scan'208";a="79500573" Received: from dpdk51.sh.intel.com ([10.67.110.190]) by fmsmga001.fm.intel.com with ESMTP; 08 Aug 2018 00:00:00 -0700 From: Qi Zhang To: thomas@monjalon.net, konstantin.ananyev@intel.com, declan.doherty@intel.com, ferruh.yigit@intel.com Cc: dev@dpdk.org, benjamin.h.shelton@intel.com, narender.vangati@intel.com, beilei.xing@intel.com, wenzhuo.lu@intel.com, 0000-cover-letter.patch, Qi Zhang Date: Wed, 8 Aug 2018 15:00:42 +0800 Message-Id: <20180808070045.13334-1-qi.z.zhang@intel.com> X-Mailer: git-send-email 2.13.6 Subject: [dpdk-dev] [RFC 1/4] ethdev: claim device reset as async X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 08 Aug 2018 07:00:07 -0000 rte_eth_dev_reset should be implemented in an async way since it is possible be invoked in interrupt thread and sometimes to reset a device need to wait for some dependency, for example, a VF expects for PF ready, or a NIC function as part of a SOC wait for the whole system reset complete, all these time consuming task will block the the interrupt thread. The patch claims rte_eth_dev_reset is an async function and introduce a new event RTE_ETH_EVENT_RESET_COMPLETE. PMD should raise this event when finish reset in background. The applicaiton should always wait for this event before continue to configure and restart the device. Signed-off-by: Qi Zhang --- lib/librte_ethdev/rte_ethdev.h | 48 ++++++++++++++++++++++++++---------------- 1 file changed, 30 insertions(+), 18 deletions(-) diff --git a/lib/librte_ethdev/rte_ethdev.h b/lib/librte_ethdev/rte_ethdev.h index 7070e9ab4..541b5161d 100644 --- a/lib/librte_ethdev/rte_ethdev.h +++ b/lib/librte_ethdev/rte_ethdev.h @@ -1814,21 +1814,34 @@ void rte_eth_dev_close(uint16_t port_id); * RTE_ETH_EVENT_INTR_RESET event is detected, but can also use it to start * a port reset in other circumstances. * - * When this function is called, it first stops the port and then calls the - * PMD specific dev_uninit( ) and dev_init( ) to return the port to initial - * state, in which no Tx and Rx queues are setup, as if the port has been - * reset and not started. The port keeps the port id it had before the - * function call. - * - * After calling rte_eth_dev_reset( ), the application should use - * rte_eth_dev_configure( ), rte_eth_rx_queue_setup( ), - * rte_eth_tx_queue_setup( ), and rte_eth_dev_start( ) - * to reconfigure the device as appropriate. - * - * Note: To avoid unexpected behavior, the application should stop calling - * Tx and Rx functions before calling rte_eth_dev_reset( ). For thread - * safety, all these controlling functions should be called from the same - * thread. + * @note + * Device reset may have the dependency, for example, a VF reset expects + * PF ready, or a NIC function as a part of a SOC need to wait for other + * parts of the system be ready, these are time-consuming tasks and will + * block current thread. + * + * So we claimed rte_eth_dev_reset as an async API, that makes things easy + * for an application that what to reset the device from the interrupt + * thread since typically a RTE_ETH_EVENT_INTR_RESET handler is invoked in + * interrupt thread. + * + * PMD is responsrible to implement ops->dev_reset in an async way, it can + * offload the whole task into a separate thread, or maybe just pending on + * hardware interrupt as reset dependency ready or start a timely alarm + * to poll register status as a background daemon. PMD is also responsible + * to raise the RTE_ETH_EVENT_RESET_COMPLETE event to notify the application + * when reset is complete. + * + * Application should not assume device reset is finished after + * rte_eth_dev_reset return, it should always wait for a + * RTE_ETH_EVENT_RESET_COMPLETE event and check the reset result. + * If reset success, application should call rte_eth_dev_configure( ), + * rte_eth_rx_queue_setup( ), rte_eth_tx_queue_setup( ), + * and rte_eth_dev_start( ) to reconfigure the device as appropriate. + * + * @Note + * To avoid unexpected behavior, the application should stop calling + * Tx and Rx functions before calling rte_eth_dev_reset( ). * * @param port_id * The port identifier of the Ethernet device. @@ -1838,9 +1851,6 @@ void rte_eth_dev_close(uint16_t port_id); * - (-EINVAL) if port identifier is invalid. * - (-ENOTSUP) if hardware doesn't support this function. * - (-EPERM) if not ran from the primary process. - * - (-EIO) if re-initialisation failed or device is removed. - * - (-ENOMEM) if the reset failed due to OOM. - * - (-EAGAIN) if the reset temporarily failed and should be retried later. */ int rte_eth_dev_reset(uint16_t port_id); @@ -2574,6 +2584,8 @@ enum rte_eth_event_type { /**< queue state event (enabled/disabled) */ RTE_ETH_EVENT_INTR_RESET, /**< reset interrupt event, sent to VF on PF reset */ + RTE_ETH_EVENT_RESET_COMPLETE, + /**< inform application that reset is completed */ RTE_ETH_EVENT_VF_MBOX, /**< message from the VF received by PF */ RTE_ETH_EVENT_MACSEC, /**< MACsec offload related event */ RTE_ETH_EVENT_INTR_RMV, /**< device removal event */ -- 2.13.6