[PATCH net v5 2/4] net: hsr: shrink seqnr_lock to sequence counter updates
From: Xin Xie <hidden>
Date: 2026-08-07 14:07:58
Also in:
linux-kselftest, lkml, stable
Subsystem:
hsr network protocol, networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
seqnr_lock currently covers the whole forwarding path although only the sequence counters need serialization. Limit it to the counter updates. The old lock also serialized the tx statistics; use DEV_STATS_INC() and DEV_STATS_ADD() for their now-concurrent updates. Concurrently forwarded frames may be emitted out of allocation order, which sparse-bitmap duplicate discard tolerates. The GSO segmentation patch depends on this shorter critical section. Apply both only to 7.0 and newer, where sparse-bitmap duplicate discard is present; older trees require an adapted backport. Cc: <redacted> # 7.0.x Signed-off-by: Xin Xie <redacted> --- net/hsr/hsr_device.c | 15 ++++----------- net/hsr/hsr_forward.c | 9 +++++---- net/hsr/hsr_slave.c | 11 +---------- 3 files changed, 10 insertions(+), 25 deletions(-)
diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c
index 5555b71ab19b..3fd1762d8916 100644
--- a/net/hsr/hsr_device.c
+++ b/net/hsr/hsr_device.c@@ -232,9 +232,7 @@ static netdev_tx_t hsr_dev_xmit(struct sk_buff *skb, struct net_device *dev) skb->dev = master->dev; skb_reset_mac_header(skb); skb_reset_mac_len(skb); - spin_lock_bh(&hsr->seqnr_lock); hsr_forward_skb(skb, master); - spin_unlock_bh(&hsr->seqnr_lock); } else { dev_core_stats_tx_dropped_inc(dev); dev_kfree_skb_any(skb);
@@ -335,6 +333,7 @@ static void send_hsr_supervision_frame(struct hsr_port *port, hsr_stag->sequence_nr = htons(hsr->sequence_nr); hsr->sequence_nr++; } + spin_unlock_bh(&hsr->seqnr_lock); hsr_stag->tlv.HSR_TLV_type = type; /* HSRv0 has 6 unused bytes after the MAC */
@@ -356,14 +355,10 @@ static void send_hsr_supervision_frame(struct hsr_port *port, ether_addr_copy(hsr_sp->macaddress_A, hsr->macaddress_redbox); } - if (skb_put_padto(skb, ETH_ZLEN)) { - spin_unlock_bh(&hsr->seqnr_lock); + if (skb_put_padto(skb, ETH_ZLEN)) return; - } hsr_forward_skb(skb, port); - spin_unlock_bh(&hsr->seqnr_lock); - return; } static void send_prp_supervision_frame(struct hsr_port *master,
@@ -390,6 +385,7 @@ static void send_prp_supervision_frame(struct hsr_port *master, spin_lock_bh(&hsr->seqnr_lock); hsr_stag->sequence_nr = htons(hsr->sup_sequence_nr); hsr->sup_sequence_nr++; + spin_unlock_bh(&hsr->seqnr_lock); hsr_stag->tlv.HSR_TLV_type = PRP_TLV_LIFE_CHECK_DD; hsr_stag->tlv.HSR_TLV_length = sizeof(struct hsr_sup_payload);
@@ -397,13 +393,10 @@ static void send_prp_supervision_frame(struct hsr_port *master, hsr_sp = skb_put(skb, sizeof(struct hsr_sup_payload)); ether_addr_copy(hsr_sp->macaddress_A, master->dev->dev_addr); - if (skb_put_padto(skb, ETH_ZLEN)) { - spin_unlock_bh(&hsr->seqnr_lock); + if (skb_put_padto(skb, ETH_ZLEN)) return; - } hsr_forward_skb(skb, master); - spin_unlock_bh(&hsr->seqnr_lock); } /* Announce (supervision frame) timer function
diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c
index 0774981a65c1..87cd72a1dc65 100644
--- a/net/hsr/hsr_forward.c
+++ b/net/hsr/hsr_forward.c@@ -621,9 +621,10 @@ static void handle_std_frame(struct sk_buff *skb, if (port->type == HSR_PT_MASTER || port->type == HSR_PT_INTERLINK) { /* Sequence nr for the master/interlink node */ - lockdep_assert_held(&hsr->seqnr_lock); + spin_lock_bh(&hsr->seqnr_lock); frame->sequence_nr = hsr->sequence_nr; hsr->sequence_nr++; + spin_unlock_bh(&hsr->seqnr_lock); } }
@@ -746,8 +747,8 @@ void hsr_forward_skb(struct sk_buff *skb, struct hsr_port *port) * So check and increment stats for master port only here. */ if (port->type == HSR_PT_MASTER || port->type == HSR_PT_INTERLINK) { - port->dev->stats.tx_packets++; - port->dev->stats.tx_bytes += skb->len; + DEV_STATS_INC(port->dev, tx_packets); + DEV_STATS_ADD(port->dev, tx_bytes, skb->len); } kfree_skb(frame.skb_hsr);
@@ -757,6 +758,6 @@ void hsr_forward_skb(struct sk_buff *skb, struct hsr_port *port) out_drop: rcu_read_unlock(); - port->dev->stats.tx_dropped++; + DEV_STATS_INC(port->dev, tx_dropped); kfree_skb(skb); }
diff --git a/net/hsr/hsr_slave.c b/net/hsr/hsr_slave.c
index 3cae70754bc4..aa2154b19c0b 100644
--- a/net/hsr/hsr_slave.c
+++ b/net/hsr/hsr_slave.c@@ -73,16 +73,7 @@ static rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb) } skb_reset_mac_len(skb); - /* Only the frames received over the interlink port will assign a - * sequence number and require synchronisation vs other sender. - */ - if (port->type == HSR_PT_INTERLINK) { - spin_lock_bh(&hsr->seqnr_lock); - hsr_forward_skb(skb, port); - spin_unlock_bh(&hsr->seqnr_lock); - } else { - hsr_forward_skb(skb, port); - } + hsr_forward_skb(skb, port); finish_consume: return RX_HANDLER_CONSUMED;
--
2.43.0