net/failsafe: fix hotplug races

[dpdk.git] / drivers / net / failsafe / failsafe_private.h

diff --git a/drivers/net/failsafe/failsafe_private.h b/drivers/net/failsafe/failsafe_private.h
index 5d328ff..5b84db9 100644 (file)
--- a/drivers/net/failsafe/failsafe_private.h
+++ b/drivers/net/failsafe/failsafe_private.h
@@ -1,40 +1,13 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright 2017 6WIND S.A.
- *   Copyright 2017 Mellanox.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *     * Neither the name of 6WIND S.A. nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2017 6WIND S.A.
+ * Copyright 2017 Mellanox.
  */
 
 #ifndef _RTE_ETH_FAILSAFE_PRIVATE_H_
 #define _RTE_ETH_FAILSAFE_PRIVATE_H_
 
 #include <sys/queue.h>
+#include <pthread.h>
 
 #include <rte_atomic.h>
 #include <rte_dev.h>
@@ -43,6 +16,7 @@
 #include <rte_interrupts.h>
 
 #define FAILSAFE_DRIVER_NAME "Fail-safe PMD"
+#define FAILSAFE_OWNER_NAME "Fail-safe"
 
 #define PMD_FAILSAFE_MAC_KVARG "mac"
 #define PMD_FAILSAFE_HOTPLUG_POLL_KVARG "hotplug_poll"
@@ -167,6 +141,7 @@ struct fs_priv {
        uint32_t mac_addr_pool[FAILSAFE_MAX_ETHADDR];
        /* current capabilities */
        struct rte_eth_dev_info infos;
+       struct rte_eth_dev_owner my_owner; /* Unique owner. */
        struct rte_intr_handle intr_handle; /* Port interrupt handle. */
        /*
         * Fail-safe state machine.
@@ -187,6 +162,9 @@ struct fs_priv {
         * appropriate failsafe Rx queue.
         */
        struct rx_proxy rxp;
+       pthread_mutex_t hotplug_mutex;
+       /* Hot-plug mutex is locked by the alarm mechanism. */
+       volatile unsigned int alarm_lock:1;
        unsigned int pending_alarm:1; /* An alarm is pending */
        /* flow isolation state */
        int flow_isolated:1;
@@ -372,6 +350,58 @@ fs_find_next(struct rte_eth_dev *dev,
        return &subs[sid];
 }
 
+/*
+ * Lock hot-plug mutex.
+ * is_alarm means that the caller is, for sure, the hot-plug alarm mechanism.
+ */
+static inline int
+fs_lock(struct rte_eth_dev *dev, unsigned int is_alarm)
+{
+       int ret;
+
+       if (is_alarm) {
+               ret = pthread_mutex_trylock(&PRIV(dev)->hotplug_mutex);
+               if (ret) {
+                       DEBUG("Hot-plug mutex lock trying failed(%s), will try"
+                             " again later...", strerror(ret));
+                       return ret;
+               }
+               PRIV(dev)->alarm_lock = 1;
+       } else {
+               ret = pthread_mutex_lock(&PRIV(dev)->hotplug_mutex);
+               if (ret) {
+                       ERROR("Cannot lock mutex(%s)", strerror(ret));
+                       return ret;
+               }
+       }
+       DEBUG("Hot-plug mutex was locked by thread %lu%s", pthread_self(),
+             PRIV(dev)->alarm_lock ? " by the hot-plug alarm" : "");
+       return ret;
+}
+
+/*
+ * Unlock hot-plug mutex.
+ * is_alarm means that the caller is, for sure, the hot-plug alarm mechanism.
+ */
+static inline void
+fs_unlock(struct rte_eth_dev *dev, unsigned int is_alarm)
+{
+       int ret;
+       unsigned int prev_alarm_lock = PRIV(dev)->alarm_lock;
+
+       if (is_alarm) {
+               RTE_ASSERT(PRIV(dev)->alarm_lock == 1);
+               PRIV(dev)->alarm_lock = 0;
+       }
+       ret = pthread_mutex_unlock(&PRIV(dev)->hotplug_mutex);
+       if (ret)
+               ERROR("Cannot unlock hot-plug mutex(%s)", strerror(ret));
+       else
+               DEBUG("Hot-plug mutex was unlocked by thread %lu%s",
+                     pthread_self(),
+                     prev_alarm_lock ? " by the hot-plug alarm" : "");
+}
+
 /*
  * Switch emitting device.
  * If banned is set, banned must not be considered for