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| author | Dan Aloni <da-x@monatomic.org> | 2007-03-02 20:44:51 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2007-03-02 20:44:51 -0800 |
| commit | 5c15bdec5c38f4ccf73ef2585fc80a6164de9554 (patch) | |
| tree | c99084e96238eb9ce40e8d9d90e0097c4e92111d /include/linux/if_vlan.h | |
| parent | b5284e5aa94be2f88dc92b29e97aff3da0c45f9f (diff) | |
| download | linux-5c15bdec5c38f4ccf73ef2585fc80a6164de9554.tar.gz linux-5c15bdec5c38f4ccf73ef2585fc80a6164de9554.tar.xz | |
[VLAN]: Avoid a 4-order allocation.
This patch splits the vlan_group struct into a multi-allocated struct. On
x86_64, the size of the original struct is a little more than 32KB, causing
a 4-order allocation, which is prune to problems caused by buddy-system
external fragmentation conditions.
I couldn't just use vmalloc() because vfree() cannot be called in the
softirq context of the RCU callback.
Signed-off-by: Dan Aloni <da-x@monatomic.org>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/linux/if_vlan.h')
| -rw-r--r-- | include/linux/if_vlan.h | 25 |
1 files changed, 22 insertions, 3 deletions
diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h index 35cb38573583..d103580c72d2 100644 --- a/include/linux/if_vlan.h +++ b/include/linux/if_vlan.h @@ -70,15 +70,34 @@ extern void vlan_ioctl_set(int (*hook)(void __user *)); * depends on completely exhausting the VLAN identifier space. Thus * it gives constant time look-up, but in many cases it wastes memory. */ -#define VLAN_GROUP_ARRAY_LEN 4096 +#define VLAN_GROUP_ARRAY_LEN 4096 +#define VLAN_GROUP_ARRAY_SPLIT_PARTS 8 +#define VLAN_GROUP_ARRAY_PART_LEN (VLAN_GROUP_ARRAY_LEN/VLAN_GROUP_ARRAY_SPLIT_PARTS) struct vlan_group { int real_dev_ifindex; /* The ifindex of the ethernet(like) device the vlan is attached to. */ struct hlist_node hlist; /* linked list */ - struct net_device *vlan_devices[VLAN_GROUP_ARRAY_LEN]; + struct net_device **vlan_devices_arrays[VLAN_GROUP_ARRAY_SPLIT_PARTS]; struct rcu_head rcu; }; +static inline struct net_device *vlan_group_get_device(struct vlan_group *vg, int vlan_id) +{ + struct net_device **array; + array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN]; + return array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN]; +} + +static inline void vlan_group_set_device(struct vlan_group *vg, int vlan_id, + struct net_device *dev) +{ + struct net_device **array; + if (!vg) + return; + array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN]; + array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] = dev; +} + struct vlan_priority_tci_mapping { unsigned long priority; unsigned short vlan_qos; /* This should be shifted when first set, so we only do it @@ -160,7 +179,7 @@ static inline int __vlan_hwaccel_rx(struct sk_buff *skb, return NET_RX_DROP; } - skb->dev = grp->vlan_devices[vlan_tag & VLAN_VID_MASK]; + skb->dev = vlan_group_get_device(grp, vlan_tag & VLAN_VID_MASK); if (skb->dev == NULL) { dev_kfree_skb_any(skb); |