[PATCH rfc v0 3/9] net: dsa: qca8K: Move queuing for request frame into the core
From: Andrew Lunn <andrew@lunn.ch>
Date: 2022-09-19 22:19:20
Subsystem:
networking drivers, networking [dsa], networking [general], qualcomm atheros qca8k dsa switch driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Andrew Lunn, Vladimir Oltean, Christian Marangi, Linus Torvalds
Combine the queuing of the request and waiting for the completion into one core helper. Add the function dsa_rmu_request() to perform this. Access to statistics is not a strict request/reply, so the dsa_rmu_wait_for_completion needs to be kept. It is also no possible to combine dsa_rmu_request() and dsa_rmu_wait_for_completion() since we need to avoid the race of sending the request, receiving a reply, and the completion has not been reinitialised because the schedule at decided to do other things. Signed-off-by: Andrew Lunn <andrew@lunn.ch> --- drivers/net/dsa/qca/qca8k-8xxx.c | 32 ++++++++++---------------------- include/net/dsa.h | 2 ++ net/dsa/dsa.c | 16 ++++++++++++++++ 3 files changed, 28 insertions(+), 22 deletions(-)
diff --git a/drivers/net/dsa/qca/qca8k-8xxx.c b/drivers/net/dsa/qca/qca8k-8xxx.c
index f4e92156bd32..9c44a09590a6 100644
--- a/drivers/net/dsa/qca/qca8k-8xxx.c
+++ b/drivers/net/dsa/qca/qca8k-8xxx.c@@ -253,10 +253,8 @@ static int qca8k_read_eth(struct qca8k_priv *priv, u32 reg, u32 *val, int len) qca8k_mdio_header_fill_seq_num(skb, mgmt_eth_data->seq); mgmt_eth_data->ack = false; - dev_queue_xmit(skb); - - ret = dsa_inband_wait_for_completion(&mgmt_eth_data->inband, - QCA8K_ETHERNET_TIMEOUT); + ret = dsa_inband_request(&mgmt_eth_data->inband, skb, + QCA8K_ETHERNET_TIMEOUT); *val = mgmt_eth_data->data[0]; if (len > QCA_HDR_MGMT_DATA1_LEN)
@@ -303,10 +301,8 @@ static int qca8k_write_eth(struct qca8k_priv *priv, u32 reg, u32 *val, int len) qca8k_mdio_header_fill_seq_num(skb, mgmt_eth_data->seq); mgmt_eth_data->ack = false; - dev_queue_xmit(skb); - - ret = dsa_inband_wait_for_completion(&mgmt_eth_data->inband, - QCA8K_ETHERNET_TIMEOUT); + ret = dsa_inband_request(&mgmt_eth_data->inband, skb, + QCA8K_ETHERNET_TIMEOUT); ack = mgmt_eth_data->ack;
@@ -449,10 +445,8 @@ qca8k_phy_eth_busy_wait(struct qca8k_mgmt_eth_data *mgmt_eth_data, qca8k_mdio_header_fill_seq_num(skb, mgmt_eth_data->seq); mgmt_eth_data->ack = false; - dev_queue_xmit(skb); - - ret = dsa_inband_wait_for_completion(&mgmt_eth_data->inband, - QCA8K_ETHERNET_TIMEOUT); + ret = dsa_inband_request(&mgmt_eth_data->inband, skb, + QCA8K_ETHERNET_TIMEOUT); ack = mgmt_eth_data->ack;
@@ -539,10 +533,8 @@ qca8k_phy_eth_command(struct qca8k_priv *priv, bool read, int phy, qca8k_mdio_header_fill_seq_num(write_skb, mgmt_eth_data->seq); mgmt_eth_data->ack = false; - dev_queue_xmit(write_skb); - - ret = dsa_inband_wait_for_completion(&mgmt_eth_data->inband, - QCA8K_ETHERNET_TIMEOUT); + ret = dsa_inband_request(&mgmt_eth_data->inband, write_skb, + QCA8K_ETHERNET_TIMEOUT); ack = mgmt_eth_data->ack;
@@ -574,10 +566,8 @@ qca8k_phy_eth_command(struct qca8k_priv *priv, bool read, int phy, qca8k_mdio_header_fill_seq_num(read_skb, mgmt_eth_data->seq); mgmt_eth_data->ack = false; - dev_queue_xmit(read_skb); - - ret = dsa_inband_wait_for_completion(&mgmt_eth_data->inband, - QCA8K_ETHERNET_TIMEOUT); + ret = dsa_inband_request(&mgmt_eth_data->inband, read_skb, + QCA8K_ETHERNET_TIMEOUT); ack = mgmt_eth_data->ack;
@@ -601,8 +591,6 @@ qca8k_phy_eth_command(struct qca8k_priv *priv, bool read, int phy, qca8k_mdio_header_fill_seq_num(clear_skb, mgmt_eth_data->seq); mgmt_eth_data->ack = false; - dev_queue_xmit(clear_skb); - dsa_inband_wait_for_completion(&mgmt_eth_data->inband, QCA8K_ETHERNET_TIMEOUT);
diff --git a/include/net/dsa.h b/include/net/dsa.h
index ca81541703f4..50c319832939 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h@@ -1286,6 +1286,8 @@ struct dsa_inband { void dsa_inband_init(struct dsa_inband *inband); void dsa_inband_complete(struct dsa_inband *inband); +int dsa_inband_request(struct dsa_inband *inband, struct sk_buff *skb, + int timeout_ms); int dsa_inband_wait_for_completion(struct dsa_inband *inband, int timeout_ms); /* Keep inline for faster access in hot path */
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 382dbb9e921a..8de0c3124abf 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c@@ -540,6 +540,22 @@ int dsa_inband_wait_for_completion(struct dsa_inband *inband, int timeout_ms) } EXPORT_SYMBOL_GPL(dsa_inband_wait_for_completion); +/* Cannot use dsa_inband_wait_completion since the completion needs to be + * reinitialized before the skb is queue to avoid races. + */ +int dsa_inband_request(struct dsa_inband *inband, struct sk_buff *skb, + int timeout_ms) +{ + unsigned long jiffies = msecs_to_jiffies(timeout_ms); + + reinit_completion(&inband->completion); + + dev_queue_xmit(skb); + + return wait_for_completion_timeout(&inband->completion, jiffies); +} +EXPORT_SYMBOL_GPL(dsa_inband_request); + static int __init dsa_init_module(void) { int rc;
--
2.37.2