diff options
| author | Longxuan Yu <ylong030@ucr.edu> | 2026-04-20 11:18:45 +0800 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2026-04-23 12:13:57 +0200 |
| commit | fc69decc811b155a0ed8eef17ee940f28c4f6dbc (patch) | |
| tree | b33e65b54f1c17a569d5548d87323afaa29edcea /include | |
| parent | 5a5db99c344810d8b4612873a8a4153bebf5776f (diff) | |
8021q: use RCU for egress QoS mappings
The TX fast path and reporting paths walk egress QoS mappings without
RTNL. Convert the mapping lists to RCU-protected pointers, use RCU
reader annotations in readers, and defer freeing mapping nodes with an
embedded rcu_head.
This prepares the egress QoS mapping code for safe removal of mapping
nodes in a follow-up change while preserving the current behavior.
Co-developed-by: Yuan Tan <yuantan098@gmail.com>
Signed-off-by: Yuan Tan <yuantan098@gmail.com>
Signed-off-by: Longxuan Yu <ylong030@ucr.edu>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Link: https://patch.msgid.link/9136768189f8c6d3f824f476c62d2fa1111688e8.1776647968.git.yuantan098@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/if_vlan.h | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h index e6272f9c5e42..20cc16ea4e5a 100644 --- a/include/linux/if_vlan.h +++ b/include/linux/if_vlan.h @@ -147,11 +147,13 @@ extern __be16 vlan_dev_vlan_proto(const struct net_device *dev); * @priority: skb priority * @vlan_qos: vlan priority: (skb->priority << 13) & 0xE000 * @next: pointer to next struct + * @rcu: used for deferred freeing of mapping nodes */ struct vlan_priority_tci_mapping { u32 priority; u16 vlan_qos; - struct vlan_priority_tci_mapping *next; + struct vlan_priority_tci_mapping __rcu *next; + struct rcu_head rcu; }; struct proc_dir_entry; @@ -177,7 +179,7 @@ struct vlan_dev_priv { unsigned int nr_ingress_mappings; u32 ingress_priority_map[8]; unsigned int nr_egress_mappings; - struct vlan_priority_tci_mapping *egress_priority_map[16]; + struct vlan_priority_tci_mapping __rcu *egress_priority_map[16]; __be16 vlan_proto; u16 vlan_id; @@ -209,19 +211,24 @@ static inline u16 vlan_dev_get_egress_qos_mask(struct net_device *dev, u32 skprio) { struct vlan_priority_tci_mapping *mp; + u16 vlan_qos = 0; - smp_rmb(); /* coupled with smp_wmb() in vlan_dev_set_egress_priority() */ + rcu_read_lock(); - mp = vlan_dev_priv(dev)->egress_priority_map[(skprio & 0xF)]; + mp = rcu_dereference(vlan_dev_priv(dev)->egress_priority_map[skprio & 0xF]); while (mp) { if (mp->priority == skprio) { - return mp->vlan_qos; /* This should already be shifted - * to mask correctly with the - * VLAN's TCI */ + vlan_qos = READ_ONCE(mp->vlan_qos); + break; } - mp = mp->next; + mp = rcu_dereference(mp->next); } - return 0; + rcu_read_unlock(); + + /* This should already be shifted to mask correctly with + * the VLAN's TCI. + */ + return vlan_qos; } extern bool vlan_do_receive(struct sk_buff **skb); |