[dpdk-stable] [PATCH 20.11] net/hns3: fix setting default MAC address in bonding of VF

["Min Hu (Connor)" <humin29@huawei.com>]

From: Chengwen Feng <fengchengwen@huawei.com>

[ upstream commit 76a3836b98c4af6b9aaeaaa50907fe6143d31c55 ]

When start testpmd with two hns3 VFs(0000:bd:01.0, 0000:bd:01.7), and
then execute the following commands:
	testpmd> create bonded device 1 0
	testpmd> set bonding mac_addr 2 3c:12:34:56:78:9a
	testpmd> add bonding slave 0 2
	testpmd> add bonding slave 1 2
	testpmd> set portmask 0x4
	testpmd> port start 2

It will occurs the following error in a low probability:
	0000:bd:01.0 hns3_get_mbx_resp(): VF could not get mbx(3,0)
		head(16) tail(15) lost(1) from PF in_irq:0
	0000:bd:01.0 hns3vf_set_default_mac_addr(): Failed to set mac
		addr(3C:**:**:**:78:9A) for vf: -62
	mac_address_slaves_update(1541) - Failed to update port Id 0
		MAC address

The problem replay:
1. The 'port start 2' command will start slave ports and then set slave
   mac address, the function call flow: bond_ethdev_start ->
   mac_address_slaves_update.
2. There are also a monitor task which running in intr thread will check
   slave ports link status and update slave ports mac address, the
   function call flow: bond_ethdev_slave_link_status_change_monitor ->
   bond_ethdev_lsc_event_callback -> mac_address_slaves_update.
3. Because the above step1&2 running on different threads, they may both
   call drivers ops mac_addr_set which is hns3vf_set_default_mac_addr.
4. hns3vf_set_default_mac_addr will first acquire hw.lock and then send
   mailbox to PF and wait PF's response message.  Note: the PF's
   response is an independent message which will received in hw.cmq.crq,
   the receiving operation can only performed in intr thread.
5. So if the step1 operation hold the hw.lock and try get response
   message, and step2 operation try acquire the hw.lock and so it can't
   process the response message, this will lead to step1 fail.

The solution:
1. make all threads could process the mailbox response message, which
   protected by the hw.cmq.crq.lock.
2. use the following rules to avoid deadlock:
2.1. ensure use the correct locking sequence: hw.lock >
     hw.mbx_resp.lock > hw.cmq.crq.lock.
2.2. make sure don't acquire such as hw.lock & hw.mbx_resp.lock again
     when process mailbox response message.

Fixes: 463e748964f5 ("net/hns3: support mailbox")
Cc: stable@dpdk.org

Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
---
 drivers/net/hns3/hns3_ethdev.h    |  1 -
 drivers/net/hns3/hns3_ethdev_vf.c |  3 ---
 drivers/net/hns3/hns3_mbx.c       | 47 +++++++++------------------------------
 3 files changed, 11 insertions(+), 40 deletions(-)

diff --git a/drivers/net/hns3/hns3_ethdev.h b/drivers/net/hns3/hns3_ethdev.h
index 4c40df1..2065592 100644
--- a/drivers/net/hns3/hns3_ethdev.h
+++ b/drivers/net/hns3/hns3_ethdev.h
@@ -424,7 +424,6 @@ struct hns3_hw {
 	struct hns3_cmq cmq;
 	struct hns3_mbx_resp_status mbx_resp; /* mailbox response */
 	struct hns3_mbx_arq_ring arq;         /* mailbox async rx queue */
-	pthread_t irq_thread_id;
 	struct hns3_mac mac;
 	unsigned int secondary_cnt; /* Number of secondary processes init'd. */
 	struct hns3_tqp_stats tqp_stats;
diff --git a/drivers/net/hns3/hns3_ethdev_vf.c b/drivers/net/hns3/hns3_ethdev_vf.c
index 52ad825..99275f1 100644
--- a/drivers/net/hns3/hns3_ethdev_vf.c
+++ b/drivers/net/hns3/hns3_ethdev_vf.c
@@ -1112,9 +1112,6 @@ hns3vf_interrupt_handler(void *param)
 	enum hns3vf_evt_cause event_cause;
 	uint32_t clearval;
 
-	if (hw->irq_thread_id == 0)
-		hw->irq_thread_id = pthread_self();
-
 	/* Disable interrupt */
 	hns3vf_disable_irq0(hw);
 
diff --git a/drivers/net/hns3/hns3_mbx.c b/drivers/net/hns3/hns3_mbx.c
index d2a5db8..975a60b 100644
--- a/drivers/net/hns3/hns3_mbx.c
+++ b/drivers/net/hns3/hns3_mbx.c
@@ -40,36 +40,14 @@ hns3_resp_to_errno(uint16_t resp_code)
 	return -EIO;
 }
 
-static void
-hns3_poll_all_sync_msg(void)
-{
-	struct rte_eth_dev *eth_dev;
-	struct hns3_adapter *adapter;
-	const char *name;
-	uint16_t port_id;
-
-	RTE_ETH_FOREACH_DEV(port_id) {
-		eth_dev = &rte_eth_devices[port_id];
-		name = eth_dev->device->driver->name;
-		if (strcmp(name, "net_hns3") && strcmp(name, "net_hns3_vf"))
-			continue;
-		adapter = eth_dev->data->dev_private;
-		if (!adapter || adapter->hw.adapter_state == HNS3_NIC_CLOSED)
-			continue;
-		/* Synchronous msg, the mbx_resp.req_msg_data is non-zero */
-		if (adapter->hw.mbx_resp.req_msg_data)
-			hns3_dev_handle_mbx_msg(&adapter->hw);
-	}
-}
-
 static int
 hns3_get_mbx_resp(struct hns3_hw *hw, uint16_t code0, uint16_t code1,
 		  uint8_t *resp_data, uint16_t resp_len)
 {
 #define HNS3_MAX_RETRY_MS	500
+#define HNS3_WAIT_RESP_US	100
 	struct hns3_adapter *hns = HNS3_DEV_HW_TO_ADAPTER(hw);
 	struct hns3_mbx_resp_status *mbx_resp;
-	bool in_irq = false;
 	uint64_t now;
 	uint64_t end;
 
@@ -96,26 +74,19 @@ hns3_get_mbx_resp(struct hns3_hw *hw, uint16_t code0, uint16_t code1,
 			return -EIO;
 		}
 
-		/*
-		 * The mbox response is running on the interrupt thread.
-		 * Sending mbox in the interrupt thread cannot wait for the
-		 * response, so polling the mbox response on the irq thread.
-		 */
-		if (pthread_equal(hw->irq_thread_id, pthread_self())) {
-			in_irq = true;
-			hns3_poll_all_sync_msg();
-		} else {
-			rte_delay_ms(HNS3_POLL_RESPONE_MS);
-		}
+		hns3_dev_handle_mbx_msg(hw);
+		rte_delay_us(HNS3_WAIT_RESP_US);
+
 		now = get_timeofday_ms();
 	}
 	hw->mbx_resp.req_msg_data = 0;
 	if (now >= end) {
 		hw->mbx_resp.lost++;
 		hns3_err(hw,
-			 "VF could not get mbx(%u,%u) head(%u) tail(%u) lost(%u) from PF in_irq:%d",
+			 "VF could not get mbx(%u,%u) head(%u) tail(%u) "
+			 "lost(%u) from PF",
 			 code0, code1, hw->mbx_resp.head, hw->mbx_resp.tail,
-			 hw->mbx_resp.lost, in_irq);
+			 hw->mbx_resp.lost);
 		return -ETIME;
 	}
 	rte_io_rmb();
@@ -365,9 +336,11 @@ hns3_dev_handle_mbx_msg(struct hns3_hw *hw)
 	uint16_t flag;
 	uint8_t *temp;
 	int i;
+	rte_spinlock_lock(&hw->cmq.crq.lock);
 
 	while (!hns3_cmd_crq_empty(hw)) {
 		if (rte_atomic16_read(&hw->reset.disable_cmd))
+			rte_spinlock_unlock(&hw->cmq.crq.lock);
 			return;
 
 		desc = &crq->desc[crq->next_to_use];
@@ -439,4 +412,6 @@ hns3_dev_handle_mbx_msg(struct hns3_hw *hw)
 
 	/* Write back CMDQ_RQ header pointer, IMP need this pointer */
 	hns3_write_dev(hw, HNS3_CMDQ_RX_HEAD_REG, crq->next_to_use);
+
+	rte_spinlock_unlock(&hw->cmq.crq.lock);
 }
-- 
2.7.4