From 27a884dc3cb63b93c2b3b643f5b31eed5f8a4d26 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 19 Apr 2007 20:29:13 -0700 Subject: [SK_BUFF]: Convert skb->tail to sk_buff_data_t So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes on 64bit architectures, allowing us to combine the 4 bytes hole left by the layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4 64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN... :-) Many calculations that previously required that skb->{transport,network, mac}_header be first converted to a pointer now can be done directly, being meaningful as offsets or pointers. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/core/dev.c | 4 ++-- net/core/filter.c | 2 +- net/core/gen_stats.c | 4 ++-- net/core/pktgen.c | 4 ++-- net/core/skbuff.c | 35 +++++++++++++++++++++-------------- net/core/wireless.c | 4 ++-- 6 files changed, 30 insertions(+), 23 deletions(-) (limited to 'net/core') diff --git a/net/core/dev.c b/net/core/dev.c index 6562e5736e2..86dc9f693f6 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1069,7 +1069,7 @@ static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) skb_reset_mac_header(skb2); if (skb_network_header(skb2) < skb2->data || - skb_network_header(skb2) > skb2->tail) { + skb2->network_header > skb2->tail) { if (net_ratelimit()) printk(KERN_CRIT "protocol %04x is " "buggy, dev %s\n", @@ -1175,7 +1175,7 @@ int skb_checksum_help(struct sk_buff *skb) BUG_ON(offset > (int)skb->len); csum = skb_checksum(skb, offset, skb->len-offset, 0); - offset = skb->tail - skb_transport_header(skb); + offset = skb->tail - skb->transport_header; BUG_ON(offset <= 0); BUG_ON(skb->csum_offset + 2 > offset); diff --git a/net/core/filter.c b/net/core/filter.c index d2358a5e633..bd903aaf7aa 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -46,7 +46,7 @@ static void *__load_pointer(struct sk_buff *skb, int k) else if (k >= SKF_LL_OFF) ptr = skb_mac_header(skb) + k - SKF_LL_OFF; - if (ptr >= skb->head && ptr < skb->tail) + if (ptr >= skb->head && ptr < skb_tail_pointer(skb)) return ptr; return NULL; } diff --git a/net/core/gen_stats.c b/net/core/gen_stats.c index 259473d0559..bcc25591d8a 100644 --- a/net/core/gen_stats.c +++ b/net/core/gen_stats.c @@ -61,7 +61,7 @@ gnet_stats_start_copy_compat(struct sk_buff *skb, int type, int tc_stats_type, spin_lock_bh(lock); d->lock = lock; if (type) - d->tail = (struct rtattr *) skb->tail; + d->tail = (struct rtattr *)skb_tail_pointer(skb); d->skb = skb; d->compat_tc_stats = tc_stats_type; d->compat_xstats = xstats_type; @@ -212,7 +212,7 @@ int gnet_stats_finish_copy(struct gnet_dump *d) { if (d->tail) - d->tail->rta_len = d->skb->tail - (u8 *) d->tail; + d->tail->rta_len = skb_tail_pointer(d->skb) - (u8 *)d->tail; if (d->compat_tc_stats) if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats, diff --git a/net/core/pktgen.c b/net/core/pktgen.c index 9da8357addc..f9469ea530c 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -2357,7 +2357,7 @@ static struct sk_buff *fill_packet_ipv4(struct net_device *odev, *vlan_encapsulated_proto = htons(ETH_P_IP); } - skb_set_network_header(skb, skb->tail - skb->data); + skb->network_header = skb->tail; skb->transport_header = skb->network_header + sizeof(struct iphdr); skb_put(skb, sizeof(struct iphdr) + sizeof(struct udphdr)); @@ -2696,7 +2696,7 @@ static struct sk_buff *fill_packet_ipv6(struct net_device *odev, *vlan_encapsulated_proto = htons(ETH_P_IPV6); } - skb_set_network_header(skb, skb->tail - skb->data); + skb->network_header = skb->tail; skb->transport_header = skb->network_header + sizeof(struct ipv6hdr); skb_put(skb, sizeof(struct ipv6hdr) + sizeof(struct udphdr)); diff --git a/net/core/skbuff.c b/net/core/skbuff.c index a48b0868126..ddcbc4d10da 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -87,8 +87,9 @@ static struct kmem_cache *skbuff_fclone_cache __read_mostly; void skb_over_panic(struct sk_buff *skb, int sz, void *here) { printk(KERN_EMERG "skb_over_panic: text:%p len:%d put:%d head:%p " - "data:%p tail:%p end:%p dev:%s\n", - here, skb->len, sz, skb->head, skb->data, skb->tail, skb->end, + "data:%p tail:%#lx end:%p dev:%s\n", + here, skb->len, sz, skb->head, skb->data, + (unsigned long)skb->tail, skb->end, skb->dev ? skb->dev->name : ""); BUG(); } @@ -105,8 +106,9 @@ void skb_over_panic(struct sk_buff *skb, int sz, void *here) void skb_under_panic(struct sk_buff *skb, int sz, void *here) { printk(KERN_EMERG "skb_under_panic: text:%p len:%d put:%d head:%p " - "data:%p tail:%p end:%p dev:%s\n", - here, skb->len, sz, skb->head, skb->data, skb->tail, skb->end, + "data:%p tail:%#lx end:%p dev:%s\n", + here, skb->len, sz, skb->head, skb->data, + (unsigned long)skb->tail, skb->end, skb->dev ? skb->dev->name : ""); BUG(); } @@ -167,7 +169,7 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask, atomic_set(&skb->users, 1); skb->head = data; skb->data = data; - skb->tail = data; + skb_reset_tail_pointer(skb); skb->end = data + size; /* make sure we initialize shinfo sequentially */ shinfo = skb_shinfo(skb); @@ -629,7 +631,12 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, /* Copy only real data... and, alas, header. This should be * optimized for the cases when header is void. */ - memcpy(data + nhead, skb->head, skb->tail - skb->head); + memcpy(data + nhead, skb->head, + skb->tail +#ifndef NET_SKBUFF_DATA_USES_OFFSET + - skb->head +#endif + ); memcpy(data + size, skb->end, sizeof(struct skb_shared_info)); for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) @@ -645,9 +652,9 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, skb->head = data; skb->end = data + size; skb->data += off; - skb->tail += off; #ifndef NET_SKBUFF_DATA_USES_OFFSET - /* {transport,network,mac}_header are relative to skb->head */ + /* {transport,network,mac}_header and tail are relative to skb->head */ + skb->tail += off; skb->transport_header += off; skb->network_header += off; skb->mac_header += off; @@ -762,7 +769,7 @@ int skb_pad(struct sk_buff *skb, int pad) return 0; } - ntail = skb->data_len + pad - (skb->end - skb->tail); + ntail = skb->data_len + pad - (skb->end - skb_tail_pointer(skb)); if (likely(skb_cloned(skb) || ntail > 0)) { err = pskb_expand_head(skb, 0, ntail, GFP_ATOMIC); if (unlikely(err)) @@ -863,7 +870,7 @@ done: } else { skb->len = len; skb->data_len = 0; - skb->tail = skb->data + len; + skb_set_tail_pointer(skb, len); } return 0; @@ -900,7 +907,7 @@ unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta) * plus 128 bytes for future expansions. If we have enough * room at tail, reallocate without expansion only if skb is cloned. */ - int i, k, eat = (skb->tail + delta) - skb->end; + int i, k, eat = (skb_tail_pointer(skb) + delta) - skb->end; if (eat > 0 || skb_cloned(skb)) { if (pskb_expand_head(skb, 0, eat > 0 ? eat + 128 : 0, @@ -908,7 +915,7 @@ unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta) return NULL; } - if (skb_copy_bits(skb, skb_headlen(skb), skb->tail, delta)) + if (skb_copy_bits(skb, skb_headlen(skb), skb_tail_pointer(skb), delta)) BUG(); /* Optimization: no fragments, no reasons to preestimate @@ -1004,7 +1011,7 @@ pull_pages: skb->tail += delta; skb->data_len -= delta; - return skb->tail; + return skb_tail_pointer(skb); } /* Copy some data bits from skb to kernel buffer. */ @@ -1539,7 +1546,7 @@ static inline void skb_split_inside_header(struct sk_buff *skb, skb1->len += skb1->data_len; skb->data_len = 0; skb->len = len; - skb->tail = skb->data + len; + skb_set_tail_pointer(skb, len); } static inline void skb_split_no_header(struct sk_buff *skb, diff --git a/net/core/wireless.c b/net/core/wireless.c index 7c6a5db544f..4a777b68e3b 100644 --- a/net/core/wireless.c +++ b/net/core/wireless.c @@ -1938,7 +1938,7 @@ static inline int rtnetlink_fill_iwinfo(struct sk_buff * skb, { struct ifinfomsg *r; struct nlmsghdr *nlh; - unsigned char *b = skb->tail; + unsigned char *b = skb_tail_pointer(skb); nlh = NLMSG_PUT(skb, 0, 0, type, sizeof(*r)); r = NLMSG_DATA(nlh); @@ -1952,7 +1952,7 @@ static inline int rtnetlink_fill_iwinfo(struct sk_buff * skb, /* Add the wireless events in the netlink packet */ RTA_PUT(skb, IFLA_WIRELESS, event_len, event); - nlh->nlmsg_len = skb->tail - b; + nlh->nlmsg_len = skb_tail_pointer(skb) - b; return skb->len; nlmsg_failure: -- cgit v1.2.3