[PATCH v12 2/5] ethdev: support proactive error handling mode

[Chengwen Feng <fengchengwen@huawei.com>]

From: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>

Some PMDs (e.g. hns3) could detect hardware or firmware errors, one
error recovery mode is to report RTE_ETH_EVENT_INTR_RESET event, and
wait for application invoke rte_eth_dev_reset() to recover the port,
however, this mode has the following weaknesses:

1) Due to different hardware and software design, some NIC port recovery
process requires multiple handshakes with the firmware and PF (when the
port is VF). It takes a long time to complete the entire operation for
one port, If multiple ports (for example, multiple VFs of a PF) are
reset at the same time, other VFs may fail to be reset. (Because the
reset processing is serial, the previous VFs must be processed before
the subsequent VFs).

2) The impact on the application layer is great, and it should stop
working queues, stop calling Rx and Tx functions, and then call
rte_eth_dev_reset(), and re-setup all again.

This patch introduces proactive error handling mode, the PMD will try
to recover from the errors itself. In this process, the PMD sets the
data path pointers to dummy functions (which will prevent the crash),
and also make sure the control path operations failed with retcode
-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.

In order to sense the error happening/recovering, three events were
introduced:

1) RTE_ETH_EVENT_ERR_RECOVERING: used to notify the application that it
detected an error and the recovery is being started. Upon receiving the
event, the application should not invoke any control path APIs until
receiving RTE_ETH_EVENT_RECOVERY_SUCCESS or
RTE_ETH_EVENT_RECOVERY_FAILED event.

2) RTE_ETH_EVENT_RECOVERY_SUCCESS: used to notify the application that
it recovers successful from the error, the PMD already re-configures the
port, and the effect is the same as that of the restart operation.

3) RTE_ETH_EVENT_RECOVERY_FAILED: used to notify the application that it
recovers failed from the error, the port should not usable anymore. The
application should close the port.

Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Somnath Kotur <somnath.kotur@broadcom.com>
Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
---
 app/test-pmd/config.c                   |  3 ++
 doc/guides/prog_guide/poll_mode_drv.rst | 38 ++++++++++++++++
 doc/guides/rel_notes/release_22_11.rst  | 12 +++++
 lib/ethdev/rte_ethdev.h                 | 59 +++++++++++++++++++++++++
 4 files changed, 112 insertions(+)

diff --git a/app/test-pmd/config.c b/app/test-pmd/config.c
index 4cddcd0bf7..0f7dbd698f 100644
--- a/app/test-pmd/config.c
+++ b/app/test-pmd/config.c
@@ -929,6 +929,9 @@ port_infos_display(portid_t port_id)
 	case RTE_ETH_ERROR_HANDLE_MODE_PASSIVE:
 		printf("passive\n");
 		break;
+	case RTE_ETH_ERROR_HANDLE_MODE_PROACTIVE:
+		printf("proactive\n");
+		break;
 	default:
 		printf("unknown\n");
 		break;
diff --git a/doc/guides/prog_guide/poll_mode_drv.rst b/doc/guides/prog_guide/poll_mode_drv.rst
index 9d081b1cba..73941a74bd 100644
--- a/doc/guides/prog_guide/poll_mode_drv.rst
+++ b/doc/guides/prog_guide/poll_mode_drv.rst
@@ -627,3 +627,41 @@ by application.
 The PMD itself should not call rte_eth_dev_reset(). The PMD can trigger
 the application to handle reset event. It is duty of application to
 handle all synchronization before it calls rte_eth_dev_reset().
+
+The above error handling mode is known as ``RTE_ETH_ERROR_HANDLE_MODE_PASSIVE``.
+
+Proactive Error Handling Mode
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+If PMD supports ``RTE_ETH_ERROR_HANDLE_MODE_PROACTIVE``, it means once detect
+hardware or firmware errors, the PMD will try to recover from the errors. In
+this process, the PMD sets the data path pointers to dummy functions (which
+will prevent the crash), and also make sure the control path operations failed
+with retcode -EBUSY.
+
+Also in this process, from the perspective of application, services are
+affected. For example, the Rx/Tx bust APIs cannot receive and send packets,
+and the control plane API return failure.
+
+In some service scenarios, application needs to be aware of the event to
+determine whether to migrate services. So three events were introduced:
+
+* RTE_ETH_EVENT_ERR_RECOVERING: used to notify the application that it detected
+  an error and the recovery is being started. Upon receiving the event, the
+  application should not invoke any control path APIs until receiving
+  RTE_ETH_EVENT_RECOVERY_SUCCESS or RTE_ETH_EVENT_RECOVERY_FAILED event.
+
+* RTE_ETH_EVENT_RECOVERY_SUCCESS: used to notify the application that it
+  recovers successful from the error, the PMD already re-configures the port,
+  and the effect is the same as that of the restart operation.
+
+* RTE_ETH_EVENT_RECOVERY_FAILED: used to notify the application that it
+  recovers failed from the error, the port should not usable anymore. the
+  application should close the port.
+
+.. 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.
+        * The error handling mode supported by the PMD can be reported through
+          the ``rte_eth_dev_info_get`` API.
diff --git a/doc/guides/rel_notes/release_22_11.rst b/doc/guides/rel_notes/release_22_11.rst
index 2da8bc9661..a3700bbb34 100644
--- a/doc/guides/rel_notes/release_22_11.rst
+++ b/doc/guides/rel_notes/release_22_11.rst
@@ -124,6 +124,18 @@ New Features
   Added new flow action which allows application to re-route packets
   directly to the kernel without software involvement.
 
+* **Added proactive error handling mode for ethdev.**
+
+  Added proactive error handling mode for ethdev, and three events were
+  introduced:
+
+  * Added new event: ``RTE_ETH_EVENT_ERR_RECOVERING`` for the PMD to report
+    that the port is recovering from an error.
+  * Added new event: ``RTE_ETH_EVENT_RECOVER_SUCCESS`` for the PMD to report
+    that the port recover successful from an error.
+  * Added new event: ``RTE_ETH_EVENT_RECOVER_FAILED`` for the PMD to report
+    that the prot recover failed from an error.
+
 * **Updated AF_XDP driver.**
 
   * Made compatible with libbpf v0.8.0 (when used with libxdp).
diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h
index 5de8e13866..46ecc9a0fe 100644
--- a/lib/ethdev/rte_ethdev.h
+++ b/lib/ethdev/rte_ethdev.h
@@ -1700,6 +1700,12 @@ enum rte_eth_err_handle_mode {
 	 * application invoke @see rte_eth_dev_reset to recover the port.
 	 */
 	RTE_ETH_ERROR_HANDLE_MODE_PASSIVE,
+	/** Proactive error handling, after the PMD detect that a reset is
+	 * required, the PMD reports @see RTE_ETH_EVENT_ERR_RECOVERING event,
+	 * and do recovery internally, finally, reports the recovery result
+	 * event (@see RTE_ETH_EVENT_RECOVERY_*).
+	 */
+	RTE_ETH_ERROR_HANDLE_MODE_PROACTIVE,
 };
 
 /**
@@ -3886,6 +3892,59 @@ enum rte_eth_event_type {
 	 * @see rte_eth_rx_avail_thresh_set()
 	 */
 	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 APIs (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 patch pointers to non-dummy functions before reports
+	 * RTE_ETH_EVENT_RECOVERY_SUCCESS event. It means that the application
+	 * cannot send or receive any packets during this period.
+	 * @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 successful from the error.
+	 * The PMD already re-configures the port, and the effect is the same as
+	 * that of the restart operation.
+	 * a) the following operation will be retained: (alphabetically)
+	 *    - DCB configuration
+	 *    - FEC configuration
+	 *    - Flow control configuration
+	 *    - LRO configuration
+	 *    - LSC configuration
+	 *    - MTU
+	 *    - Mac address (default and those supplied by MAC address array)
+	 *    - Promiscuous and allmulticast mode
+	 *    - PTP configuration
+	 *    - Queue (Rx/Tx) settings
+	 *    - Queue statistics mappings
+	 *    - RSS configuration by rte_eth_dev_rss_xxx() family
+	 *    - Rx checksum configuration
+	 *    - Rx interrupt settings
+	 *    - Traffic management configuration
+	 *    - VLAN configuration (including filtering, tpid, strip, pvid)
+	 *    - VMDq configuration
+	 * b) the following configuration maybe retained or not depending on the
+	 *    device capabilities:
+	 *    - flow rules
+	 *      @see RTE_ETH_DEV_CAPA_FLOW_RULE_KEEP
+	 *    - shared flow objects
+	 *      @see RTE_ETH_DEV_CAPA_FLOW_SHARED_OBJECT_KEEP
+	 * c) the other configuration will not be stored and will need to be
+	 *    re-configured.
+	 */
+	RTE_ETH_EVENT_RECOVERY_SUCCESS,
+	/** Port recovers failed from the error.
+	 * It means that the port should not usable anymore. The application
+	 * should close the port.
+	 */
+	RTE_ETH_EVENT_RECOVERY_FAILED,
 	RTE_ETH_EVENT_MAX       /**< max value of this enum */
 };
 
-- 
2.17.1