[dpdk-dev] [PATCH v2] net/hns3: add runtime config to set MBX limit time

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

From: Chengchang Tang <tangchengchang@huawei.com>

Current, the max waiting time for MBX response is 500ms, but in
some scenarios, it is not enough. Since it depends on the response
of the kernel mode driver, and its response time is related to the
scheduling of the system. In this special scenario, most of the
cores are isolated, and only a few cores are used for system
scheduling. When a large number of services are started, the
scheduling of the system will be very busy, and the reply of the
mbx message will time out, which will cause our PMD initialization
to fail.

This patch add a runtime config to set the max wait time. For the
above scenes, users can adjust the waiting time to a suitable value
by themselves.

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

Signed-off-by: Chengchang Tang <tangchengchang@huawei.com>
Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
---
v2:
* add some comment for HNS3_MBX_DEF_TIME_LIMIT_MS.
* remove some check for mbx_time_limit.
---
 drivers/net/hns3/hns3_ethdev.c    | 32 ++++++++++++++++++++++++++++++-
 drivers/net/hns3/hns3_ethdev.h    |  3 +++
 drivers/net/hns3/hns3_ethdev_vf.c |  3 ++-
 drivers/net/hns3/hns3_mbx.c       |  8 +++++---
 drivers/net/hns3/hns3_mbx.h       |  1 +
 5 files changed, 42 insertions(+), 5 deletions(-)

diff --git a/drivers/net/hns3/hns3_ethdev.c b/drivers/net/hns3/hns3_ethdev.c
index 693048f587..6b89bcef97 100644
--- a/drivers/net/hns3/hns3_ethdev.c
+++ b/drivers/net/hns3/hns3_ethdev.c
@@ -7306,9 +7306,30 @@ hns3_parse_dev_caps_mask(const char *key, const char *value, void *extra_args)
 	return 0;
 }
 
+static int
+hns3_parse_mbx_time_limit(const char *key, const char *value, void *extra_args)
+{
+	uint32_t val;
+
+	RTE_SET_USED(key);
+
+	val = strtoul(value, NULL, 10);
+
+	/*
+	 * 500ms is empirical value in process of mailbox communication. If
+	 * the delay value is set to one lower thanthe empirical value, mailbox
+	 * communication may fail.
+	 */
+	if (val > HNS3_MBX_DEF_TIME_LIMIT_MS && val <= UINT16_MAX)
+		*(uint16_t *)extra_args = val;
+
+	return 0;
+}
+
 void
 hns3_parse_devargs(struct rte_eth_dev *dev)
 {
+	uint16_t mbx_time_limit_ms = HNS3_MBX_DEF_TIME_LIMIT_MS;
 	struct hns3_adapter *hns = dev->data->dev_private;
 	uint32_t rx_func_hint = HNS3_IO_FUNC_HINT_NONE;
 	uint32_t tx_func_hint = HNS3_IO_FUNC_HINT_NONE;
@@ -7329,6 +7350,9 @@ hns3_parse_devargs(struct rte_eth_dev *dev)
 			   &hns3_parse_io_hint_func, &tx_func_hint);
 	(void)rte_kvargs_process(kvlist, HNS3_DEVARG_DEV_CAPS_MASK,
 			   &hns3_parse_dev_caps_mask, &dev_caps_mask);
+	(void)rte_kvargs_process(kvlist, HNS3_DEVARG_MBX_TIME_LIMIT_MS,
+			   &hns3_parse_mbx_time_limit, &mbx_time_limit_ms);
+
 	rte_kvargs_free(kvlist);
 
 	if (rx_func_hint != HNS3_IO_FUNC_HINT_NONE)
@@ -7344,6 +7368,11 @@ hns3_parse_devargs(struct rte_eth_dev *dev)
 		hns3_warn(hw, "parsed %s = 0x%" PRIx64 ".",
 			  HNS3_DEVARG_DEV_CAPS_MASK, dev_caps_mask);
 	hns->dev_caps_mask = dev_caps_mask;
+
+	if (mbx_time_limit_ms != HNS3_MBX_DEF_TIME_LIMIT_MS)
+		hns3_warn(hw, "parsed %s = %u.", HNS3_DEVARG_MBX_TIME_LIMIT_MS,
+				mbx_time_limit_ms);
+	hns->mbx_time_limit_ms = mbx_time_limit_ms;
 }
 
 static const struct eth_dev_ops hns3_eth_dev_ops = {
@@ -7600,6 +7629,7 @@ RTE_PMD_REGISTER_KMOD_DEP(net_hns3, "* igb_uio | vfio-pci");
 RTE_PMD_REGISTER_PARAM_STRING(net_hns3,
 		HNS3_DEVARG_RX_FUNC_HINT "=vec|sve|simple|common "
 		HNS3_DEVARG_TX_FUNC_HINT "=vec|sve|simple|common "
-		HNS3_DEVARG_DEV_CAPS_MASK "=<1-65535> ");
+		HNS3_DEVARG_DEV_CAPS_MASK "=<1-65535> "
+		HNS3_DEVARG_MBX_TIME_LIMIT_MS "=<uint16> ");
 RTE_LOG_REGISTER_SUFFIX(hns3_logtype_init, init, NOTICE);
 RTE_LOG_REGISTER_SUFFIX(hns3_logtype_driver, driver, NOTICE);
diff --git a/drivers/net/hns3/hns3_ethdev.h b/drivers/net/hns3/hns3_ethdev.h
index e28056b1bd..fa08fadc94 100644
--- a/drivers/net/hns3/hns3_ethdev.h
+++ b/drivers/net/hns3/hns3_ethdev.h
@@ -851,6 +851,7 @@ struct hns3_adapter {
 	uint32_t tx_func_hint;
 
 	uint64_t dev_caps_mask;
+	uint16_t mbx_time_limit_ms; /* wait time for mbx message */
 
 	struct hns3_ptype_table ptype_tbl __rte_cache_aligned;
 };
@@ -868,6 +869,8 @@ enum {
 
 #define HNS3_DEVARG_DEV_CAPS_MASK	"dev_caps_mask"
 
+#define HNS3_DEVARG_MBX_TIME_LIMIT_MS	"mbx_time_limit_ms"
+
 enum {
 	HNS3_DEV_SUPPORT_DCB_B,
 	HNS3_DEV_SUPPORT_COPPER_B,
diff --git a/drivers/net/hns3/hns3_ethdev_vf.c b/drivers/net/hns3/hns3_ethdev_vf.c
index 54dbd4b798..8e5df05aa2 100644
--- a/drivers/net/hns3/hns3_ethdev_vf.c
+++ b/drivers/net/hns3/hns3_ethdev_vf.c
@@ -3086,4 +3086,5 @@ RTE_PMD_REGISTER_KMOD_DEP(net_hns3_vf, "* igb_uio | vfio-pci");
 RTE_PMD_REGISTER_PARAM_STRING(net_hns3_vf,
 		HNS3_DEVARG_RX_FUNC_HINT "=vec|sve|simple|common "
 		HNS3_DEVARG_TX_FUNC_HINT "=vec|sve|simple|common "
-		HNS3_DEVARG_DEV_CAPS_MASK "=<1-65535> ");
+		HNS3_DEVARG_DEV_CAPS_MASK "=<1-65535> "
+		HNS3_DEVARG_MBX_TIME_LIMIT_MS "=<uint16_t> ");
diff --git a/drivers/net/hns3/hns3_mbx.c b/drivers/net/hns3/hns3_mbx.c
index f36cb10d08..a47622b8a6 100644
--- a/drivers/net/hns3/hns3_mbx.c
+++ b/drivers/net/hns3/hns3_mbx.c
@@ -61,8 +61,9 @@ static int
 hns3_get_mbx_resp(struct hns3_hw *hw, uint16_t code, uint16_t subcode,
 		  uint8_t *resp_data, uint16_t resp_len)
 {
-#define HNS3_MAX_RETRY_US	500000
 #define HNS3_WAIT_RESP_US	100
+#define US_PER_MS		1000
+	uint32_t mbx_time_limit;
 	struct hns3_adapter *hns = HNS3_DEV_HW_TO_ADAPTER(hw);
 	struct hns3_mbx_resp_status *mbx_resp;
 	uint32_t wait_time = 0;
@@ -74,7 +75,8 @@ hns3_get_mbx_resp(struct hns3_hw *hw, uint16_t code, uint16_t subcode,
 		return -EINVAL;
 	}
 
-	while (wait_time < HNS3_MAX_RETRY_US) {
+	mbx_time_limit = (uint32_t)hns->mbx_time_limit_ms * US_PER_MS;
+	while (wait_time < mbx_time_limit) {
 		if (__atomic_load_n(&hw->reset.disable_cmd, __ATOMIC_RELAXED)) {
 			hns3_err(hw, "Don't wait for mbx respone because of "
 				 "disable_cmd");
@@ -103,7 +105,7 @@ hns3_get_mbx_resp(struct hns3_hw *hw, uint16_t code, uint16_t subcode,
 		wait_time += HNS3_WAIT_RESP_US;
 	}
 	hw->mbx_resp.req_msg_data = 0;
-	if (wait_time >= HNS3_MAX_RETRY_US) {
+	if (wait_time >= mbx_time_limit) {
 		hns3_mbx_proc_timeout(hw, code, subcode);
 		return -ETIME;
 	}
diff --git a/drivers/net/hns3/hns3_mbx.h b/drivers/net/hns3/hns3_mbx.h
index f868e33a9e..d637bd2b23 100644
--- a/drivers/net/hns3/hns3_mbx.h
+++ b/drivers/net/hns3/hns3_mbx.h
@@ -87,6 +87,7 @@ enum hns3_mbx_link_fail_subcode {
 
 #define HNS3_MBX_MAX_MSG_SIZE	16
 #define HNS3_MBX_MAX_RESP_DATA_SIZE	8
+#define HNS3_MBX_DEF_TIME_LIMIT_MS	500
 
 enum {
 	HNS3_MBX_RESP_MATCHING_SCHEME_OF_ORIGINAL = 0,
-- 
2.33.0