[dpdk-dev] [PATCH v5] net/ixgbe: fix resource leak after thread exits normally

[taox.zhu@intel.com]

From: Zhu Tao <taox.zhu@intel.com>

When the thread exits normally, pthread_join() is not called, which can
result in a resource leak. Therefore, the thread is set to separation
mode using function pthread_detach(), so that no program call
pthread_join() is required to recycle, and when the thread exits,
the system automatically reclaims resources.

Wait for the thread to finish with timeout argument(0 means that it will
not return until link complete), wait until the thread finishes before
returning. Normally, the thread will finish in a shorter time, and give
a warning message if it hasn't finished in a longer time.

Fixes: 819d0d1d57f1 ("net/ixgbe: fix blocking system events")
Cc: stable@dpdk.org

Signed-off-by: Zhu Tao <taox.zhu@intel.com>
---
 drivers/net/ixgbe/ixgbe_ethdev.c | 57 +++++++++++++++++++---------------------
 1 file changed, 27 insertions(+), 30 deletions(-)

V5 changes:
	Modify the definition of function ixgbe_dev_wait_setup_link_complete(),
	 so that the caller can choose whether to block, etc.

v4 changes:
	Format codes.

v3 changes:
        1. Wait for the thread to finish without setting the timeout, and the
           corresponding function name has also been modified.
        2. Commit log.

v2 changes:
        Commit log.

diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
index 2c57976..92788ee 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.c
+++ b/drivers/net/ixgbe/ixgbe_ethdev.c
@@ -230,7 +230,7 @@ static int ixgbe_dev_rss_reta_query(struct rte_eth_dev *dev,
 static void ixgbe_dev_interrupt_handler(void *param);
 static void ixgbe_dev_interrupt_delayed_handler(void *param);
 static void *ixgbe_dev_setup_link_thread_handler(void *param);
-static void ixgbe_dev_cancel_link_thread(struct rte_eth_dev *dev);
+static int ixgbe_dev_wait_setup_link_complete(struct rte_eth_dev *dev, uint32_t timeout_ms);
 
 static int ixgbe_add_rar(struct rte_eth_dev *dev,
 			struct rte_ether_addr *mac_addr,
@@ -2601,7 +2601,7 @@ static int eth_ixgbevf_pci_remove(struct rte_pci_device *pci_dev)
 	PMD_INIT_FUNC_TRACE();
 
 	/* Stop the link setup handler before resetting the HW. */
-	ixgbe_dev_cancel_link_thread(dev);
+	ixgbe_dev_wait_setup_link_complete(dev, 0);
 
 	/* disable uio/vfio intr/eventfd mapping */
 	rte_intr_disable(intr_handle);
@@ -2888,7 +2888,7 @@ static int eth_ixgbevf_pci_remove(struct rte_pci_device *pci_dev)
 
 	PMD_INIT_FUNC_TRACE();
 
-	ixgbe_dev_cancel_link_thread(dev);
+	ixgbe_dev_wait_setup_link_complete(dev, 0);
 
 	/* disable interrupts */
 	ixgbe_disable_intr(hw);
@@ -4143,36 +4143,32 @@ static int ixgbevf_dev_xstats_get_names(__rte_unused struct rte_eth_dev *dev,
 	return ret_val;
 }
 
-/* return 1: setup complete, return 0: setup not complete, and wait timeout*/
+/*
+ * If @timeout_ms was 0, it means that it will not return until link complete.
+ * It returns 1 on complete, return 0 on timeout.
+ */
 static int
-ixgbe_dev_wait_setup_link_complete(struct rte_eth_dev *dev)
+ixgbe_dev_wait_setup_link_complete(struct rte_eth_dev *dev, uint32_t timeout_ms)
 {
-#define DELAY_INTERVAL 100 /* 100ms */
-#define MAX_TIMEOUT    90 /* 9s (90 * 100ms) in total */
+#define WARNING_TIMEOUT    9000 /* 9s  in total */
 	struct ixgbe_adapter *ad = dev->data->dev_private;
-	int timeout = MAX_TIMEOUT;
+	int timeout = timeout_ms ? WARNING_TIMEOUT : timeout_ms;
 
-	while (rte_atomic32_read(&ad->link_thread_running) && timeout) {
-		msec_delay(DELAY_INTERVAL);
+	while (rte_atomic32_read(&ad->link_thread_running)) {
+		msec_delay(1);
 		timeout--;
-	}
-
-
-	return !!timeout;
-}
 
-static void
-ixgbe_dev_cancel_link_thread(struct rte_eth_dev *dev)
-{
-	struct ixgbe_adapter *ad = dev->data->dev_private;
-	void *retval;
-
-	if (!ixgbe_dev_wait_setup_link_complete(dev)) {
-		pthread_cancel(ad->link_thread_tid);
-		pthread_join(ad->link_thread_tid, &retval);
-		rte_atomic32_clear(&ad->link_thread_running);
-		PMD_DRV_LOG(ERR, "Link thread not complete, cancel it!");
+		if (timeout_ms) {
+			if (!timeout)
+				return 0;
+		} else if (!timeout) {
+			/* It will not return until link complete */
+			timeout = WARNING_TIMEOUT;
+			PMD_DRV_LOG(ERR, "IXGBE link thread not complete too long time!");
+		}
 	}
+
+	return 1;
 }
 
 static void *
@@ -4186,6 +4182,7 @@ static int ixgbevf_dev_xstats_get_names(__rte_unused struct rte_eth_dev *dev,
 	u32 speed;
 	bool autoneg = false;
 
+	pthread_detach(pthread_self());
 	speed = hw->phy.autoneg_advertised;
 	if (!speed)
 		ixgbe_get_link_capabilities(hw, &speed, &autoneg);
@@ -4282,8 +4279,8 @@ static int ixgbevf_dev_xstats_get_names(__rte_unused struct rte_eth_dev *dev,
 	if (link_up == 0) {
 		if (ixgbe_get_media_type(hw) == ixgbe_media_type_fiber) {
 			intr->flags |= IXGBE_FLAG_NEED_LINK_CONFIG;
-			if (ixgbe_dev_wait_setup_link_complete(dev) &&
-			    rte_atomic32_test_and_set(&ad->link_thread_running)) {
+			ixgbe_dev_wait_setup_link_complete(dev, 0);
+			if (rte_atomic32_test_and_set(&ad->link_thread_running)) {
 				if (rte_ctrl_thread_create(&ad->link_thread_tid,
 					"ixgbe-link-handler",
 					NULL,
@@ -5323,7 +5320,7 @@ static int ixgbevf_dev_xstats_get_names(__rte_unused struct rte_eth_dev *dev,
 	PMD_INIT_FUNC_TRACE();
 
 	/* Stop the link setup handler before resetting the HW. */
-	ixgbe_dev_cancel_link_thread(dev);
+	ixgbe_dev_wait_setup_link_complete(dev, 0);
 
 	err = hw->mac.ops.reset_hw(hw);
 	if (err) {
@@ -5421,7 +5418,7 @@ static int ixgbevf_dev_xstats_get_names(__rte_unused struct rte_eth_dev *dev,
 
 	PMD_INIT_FUNC_TRACE();
 
-	ixgbe_dev_cancel_link_thread(dev);
+	ixgbe_dev_wait_setup_link_complete(dev, 0);
 
 	ixgbevf_intr_disable(dev);
 
-- 
1.8.3.1