From 7f68cac81d83667404d41a6dc0fa77b58b673e66 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Sun, 10 May 2009 22:17:50 +0000 Subject: [PATCH] improve the skb padding performance change to avoid unnecessary reallocations in the routing code SVN-Revision: 15761 --- .../patches-2.6.28/205-skb_padding.patch | 48 +++++++++++++++++-- .../patches-2.6.29/205-skb_padding.patch | 48 +++++++++++++++++-- .../patches-2.6.30/205-skb_padding.patch | 48 +++++++++++++++++-- 3 files changed, 132 insertions(+), 12 deletions(-) diff --git a/target/linux/generic-2.6/patches-2.6.28/205-skb_padding.patch b/target/linux/generic-2.6/patches-2.6.28/205-skb_padding.patch index 07e730a206..855f0fedd5 100644 --- a/target/linux/generic-2.6/patches-2.6.28/205-skb_padding.patch +++ b/target/linux/generic-2.6/patches-2.6.28/205-skb_padding.patch @@ -1,16 +1,56 @@ --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h -@@ -1270,9 +1270,12 @@ +@@ -1256,11 +1256,18 @@ static inline int skb_network_offset(con * * Various parts of the networking layer expect at least 16 bytes of * headroom, you should not reduce this. + * + * This has been changed to 64 to acommodate for routing between ethernet -+ * and wireless ++ * and wireless, but only for new allocations */ #ifndef NET_SKB_PAD --#define NET_SKB_PAD 16 -+#define NET_SKB_PAD 64 + #define NET_SKB_PAD 16 #endif ++#ifndef NET_SKB_PAD_ALLOC ++#define NET_SKB_PAD_ALLOC 64 ++#endif ++ extern int ___pskb_trim(struct sk_buff *skb, unsigned int len); + + static inline void __skb_trim(struct sk_buff *skb, unsigned int len) +@@ -1350,9 +1357,9 @@ static inline void __skb_queue_purge(str + static inline struct sk_buff *__dev_alloc_skb(unsigned int length, + gfp_t gfp_mask) + { +- struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask); ++ struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD_ALLOC, gfp_mask); + if (likely(skb)) +- skb_reserve(skb, NET_SKB_PAD); ++ skb_reserve(skb, NET_SKB_PAD_ALLOC); + return skb; + } + +@@ -1425,7 +1432,7 @@ static inline int __skb_cow(struct sk_bu + delta = headroom - skb_headroom(skb); + + if (delta || cloned) +- return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0, ++ return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD_ALLOC), 0, + GFP_ATOMIC); + return 0; + } +--- a/net/core/skbuff.c ++++ b/net/core/skbuff.c +@@ -243,9 +243,9 @@ struct sk_buff *__netdev_alloc_skb(struc + int node = dev->dev.parent ? dev_to_node(dev->dev.parent) : -1; + struct sk_buff *skb; + +- skb = __alloc_skb(length + NET_SKB_PAD, gfp_mask, 0, node); ++ skb = __alloc_skb(length + NET_SKB_PAD_ALLOC, gfp_mask, 0, node); + if (likely(skb)) { +- skb_reserve(skb, NET_SKB_PAD); ++ skb_reserve(skb, NET_SKB_PAD_ALLOC); + skb->dev = dev; + } + return skb; diff --git a/target/linux/generic-2.6/patches-2.6.29/205-skb_padding.patch b/target/linux/generic-2.6/patches-2.6.29/205-skb_padding.patch index c11bffe550..ff05b8d930 100644 --- a/target/linux/generic-2.6/patches-2.6.29/205-skb_padding.patch +++ b/target/linux/generic-2.6/patches-2.6.29/205-skb_padding.patch @@ -1,16 +1,56 @@ --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h -@@ -1306,9 +1306,12 @@ +@@ -1306,11 +1306,18 @@ static inline int skb_network_offset(con * * Various parts of the networking layer expect at least 16 bytes of * headroom, you should not reduce this. + * + * This has been changed to 64 to acommodate for routing between ethernet -+ * and wireless ++ * and wireless, but only for new allocations */ #ifndef NET_SKB_PAD --#define NET_SKB_PAD 16 -+#define NET_SKB_PAD 64 + #define NET_SKB_PAD 16 #endif ++#ifndef NET_SKB_PAD_ALLOC ++#define NET_SKB_PAD_ALLOC 64 ++#endif ++ extern int ___pskb_trim(struct sk_buff *skb, unsigned int len); + + static inline void __skb_trim(struct sk_buff *skb, unsigned int len) +@@ -1400,9 +1407,9 @@ static inline void __skb_queue_purge(str + static inline struct sk_buff *__dev_alloc_skb(unsigned int length, + gfp_t gfp_mask) + { +- struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask); ++ struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD_ALLOC, gfp_mask); + if (likely(skb)) +- skb_reserve(skb, NET_SKB_PAD); ++ skb_reserve(skb, NET_SKB_PAD_ALLOC); + return skb; + } + +@@ -1475,7 +1482,7 @@ static inline int __skb_cow(struct sk_bu + delta = headroom - skb_headroom(skb); + + if (delta || cloned) +- return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0, ++ return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD_ALLOC), 0, + GFP_ATOMIC); + return 0; + } +--- a/net/core/skbuff.c ++++ b/net/core/skbuff.c +@@ -320,9 +320,9 @@ struct sk_buff *__netdev_alloc_skb(struc + int node = dev->dev.parent ? dev_to_node(dev->dev.parent) : -1; + struct sk_buff *skb; + +- skb = __alloc_skb(length + NET_SKB_PAD, gfp_mask, 0, node); ++ skb = __alloc_skb(length + NET_SKB_PAD_ALLOC, gfp_mask, 0, node); + if (likely(skb)) { +- skb_reserve(skb, NET_SKB_PAD); ++ skb_reserve(skb, NET_SKB_PAD_ALLOC); + skb->dev = dev; + } + return skb; diff --git a/target/linux/generic-2.6/patches-2.6.30/205-skb_padding.patch b/target/linux/generic-2.6/patches-2.6.30/205-skb_padding.patch index 549fa50c9a..06b494b91b 100644 --- a/target/linux/generic-2.6/patches-2.6.30/205-skb_padding.patch +++ b/target/linux/generic-2.6/patches-2.6.30/205-skb_padding.patch @@ -1,16 +1,56 @@ --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h -@@ -1369,9 +1369,12 @@ static inline int skb_network_offset(con +@@ -1369,11 +1369,18 @@ static inline int skb_network_offset(con * * Various parts of the networking layer expect at least 32 bytes of * headroom, you should not reduce this. + * + * This has been changed to 64 to acommodate for routing between ethernet -+ * and wireless ++ * and wireless, but only for new allocations */ #ifndef NET_SKB_PAD --#define NET_SKB_PAD 32 -+#define NET_SKB_PAD 64 + #define NET_SKB_PAD 32 #endif ++#ifndef NET_SKB_PAD_ALLOC ++#define NET_SKB_PAD_ALLOC 64 ++#endif ++ extern int ___pskb_trim(struct sk_buff *skb, unsigned int len); + + static inline void __skb_trim(struct sk_buff *skb, unsigned int len) +@@ -1463,9 +1470,9 @@ static inline void __skb_queue_purge(str + static inline struct sk_buff *__dev_alloc_skb(unsigned int length, + gfp_t gfp_mask) + { +- struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask); ++ struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD_ALLOC, gfp_mask); + if (likely(skb)) +- skb_reserve(skb, NET_SKB_PAD); ++ skb_reserve(skb, NET_SKB_PAD_ALLOC); + return skb; + } + +@@ -1538,7 +1545,7 @@ static inline int __skb_cow(struct sk_bu + delta = headroom - skb_headroom(skb); + + if (delta || cloned) +- return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0, ++ return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD_ALLOC), 0, + GFP_ATOMIC); + return 0; + } +--- a/net/core/skbuff.c ++++ b/net/core/skbuff.c +@@ -327,9 +327,9 @@ struct sk_buff *__netdev_alloc_skb(struc + int node = dev->dev.parent ? dev_to_node(dev->dev.parent) : -1; + struct sk_buff *skb; + +- skb = __alloc_skb(length + NET_SKB_PAD, gfp_mask, 0, node); ++ skb = __alloc_skb(length + NET_SKB_PAD_ALLOC, gfp_mask, 0, node); + if (likely(skb)) { +- skb_reserve(skb, NET_SKB_PAD); ++ skb_reserve(skb, NET_SKB_PAD_ALLOC); + skb->dev = dev; + } + return skb; -- 2.30.2