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-rw-r--r--net/core/skbuff.c158
1 files changed, 103 insertions, 55 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 7eab867ede59..f80a28785610 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -68,7 +68,10 @@
#include <asm/uaccess.h>
#include <asm/system.h>
-static kmem_cache_t *skbuff_head_cache;
+static kmem_cache_t *skbuff_head_cache __read_mostly;
+static kmem_cache_t *skbuff_fclone_cache __read_mostly;
+
+struct timeval __read_mostly skb_tv_base;
/*
* Keep out-of-line to prevent kernel bloat.
@@ -118,7 +121,7 @@ void skb_under_panic(struct sk_buff *skb, int sz, void *here)
*/
/**
- * alloc_skb - allocate a network buffer
+ * __alloc_skb - allocate a network buffer
* @size: size to allocate
* @gfp_mask: allocation mask
*
@@ -129,14 +132,20 @@ void skb_under_panic(struct sk_buff *skb, int sz, void *here)
* Buffers may only be allocated from interrupts using a @gfp_mask of
* %GFP_ATOMIC.
*/
-struct sk_buff *alloc_skb(unsigned int size, unsigned int __nocast gfp_mask)
+struct sk_buff *__alloc_skb(unsigned int size, unsigned int __nocast gfp_mask,
+ int fclone)
{
struct sk_buff *skb;
u8 *data;
/* Get the HEAD */
- skb = kmem_cache_alloc(skbuff_head_cache,
- gfp_mask & ~__GFP_DMA);
+ if (fclone)
+ skb = kmem_cache_alloc(skbuff_fclone_cache,
+ gfp_mask & ~__GFP_DMA);
+ else
+ skb = kmem_cache_alloc(skbuff_head_cache,
+ gfp_mask & ~__GFP_DMA);
+
if (!skb)
goto out;
@@ -153,7 +162,15 @@ struct sk_buff *alloc_skb(unsigned int size, unsigned int __nocast gfp_mask)
skb->data = data;
skb->tail = data;
skb->end = data + size;
+ if (fclone) {
+ struct sk_buff *child = skb + 1;
+ atomic_t *fclone_ref = (atomic_t *) (child + 1);
+ skb->fclone = SKB_FCLONE_ORIG;
+ atomic_set(fclone_ref, 1);
+
+ child->fclone = SKB_FCLONE_UNAVAILABLE;
+ }
atomic_set(&(skb_shinfo(skb)->dataref), 1);
skb_shinfo(skb)->nr_frags = 0;
skb_shinfo(skb)->tso_size = 0;
@@ -266,8 +283,34 @@ void skb_release_data(struct sk_buff *skb)
*/
void kfree_skbmem(struct sk_buff *skb)
{
+ struct sk_buff *other;
+ atomic_t *fclone_ref;
+
skb_release_data(skb);
- kmem_cache_free(skbuff_head_cache, skb);
+ switch (skb->fclone) {
+ case SKB_FCLONE_UNAVAILABLE:
+ kmem_cache_free(skbuff_head_cache, skb);
+ break;
+
+ case SKB_FCLONE_ORIG:
+ fclone_ref = (atomic_t *) (skb + 2);
+ if (atomic_dec_and_test(fclone_ref))
+ kmem_cache_free(skbuff_fclone_cache, skb);
+ break;
+
+ case SKB_FCLONE_CLONE:
+ fclone_ref = (atomic_t *) (skb + 1);
+ other = skb - 1;
+
+ /* The clone portion is available for
+ * fast-cloning again.
+ */
+ skb->fclone = SKB_FCLONE_UNAVAILABLE;
+
+ if (atomic_dec_and_test(fclone_ref))
+ kmem_cache_free(skbuff_fclone_cache, other);
+ break;
+ };
}
/**
@@ -281,8 +324,6 @@ void kfree_skbmem(struct sk_buff *skb)
void __kfree_skb(struct sk_buff *skb)
{
- BUG_ON(skb->list != NULL);
-
dst_release(skb->dst);
#ifdef CONFIG_XFRM
secpath_put(skb->sp);
@@ -302,7 +343,6 @@ void __kfree_skb(struct sk_buff *skb)
skb->tc_index = 0;
#ifdef CONFIG_NET_CLS_ACT
skb->tc_verd = 0;
- skb->tc_classid = 0;
#endif
#endif
@@ -325,19 +365,27 @@ void __kfree_skb(struct sk_buff *skb)
struct sk_buff *skb_clone(struct sk_buff *skb, unsigned int __nocast gfp_mask)
{
- struct sk_buff *n = kmem_cache_alloc(skbuff_head_cache, gfp_mask);
-
- if (!n)
- return NULL;
+ struct sk_buff *n;
+
+ n = skb + 1;
+ if (skb->fclone == SKB_FCLONE_ORIG &&
+ n->fclone == SKB_FCLONE_UNAVAILABLE) {
+ atomic_t *fclone_ref = (atomic_t *) (n + 1);
+ n->fclone = SKB_FCLONE_CLONE;
+ atomic_inc(fclone_ref);
+ } else {
+ n = kmem_cache_alloc(skbuff_head_cache, gfp_mask);
+ if (!n)
+ return NULL;
+ n->fclone = SKB_FCLONE_UNAVAILABLE;
+ }
#define C(x) n->x = skb->x
n->next = n->prev = NULL;
- n->list = NULL;
n->sk = NULL;
- C(stamp);
+ C(tstamp);
C(dev);
- C(real_dev);
C(h);
C(nh);
C(mac);
@@ -361,7 +409,6 @@ struct sk_buff *skb_clone(struct sk_buff *skb, unsigned int __nocast gfp_mask)
n->destructor = NULL;
#ifdef CONFIG_NETFILTER
C(nfmark);
- C(nfcache);
C(nfct);
nf_conntrack_get(skb->nfct);
C(nfctinfo);
@@ -370,9 +417,6 @@ struct sk_buff *skb_clone(struct sk_buff *skb, unsigned int __nocast gfp_mask)
nf_bridge_get(skb->nf_bridge);
#endif
#endif /*CONFIG_NETFILTER*/
-#if defined(CONFIG_HIPPI)
- C(private);
-#endif
#ifdef CONFIG_NET_SCHED
C(tc_index);
#ifdef CONFIG_NET_CLS_ACT
@@ -380,7 +424,6 @@ struct sk_buff *skb_clone(struct sk_buff *skb, unsigned int __nocast gfp_mask)
n->tc_verd = CLR_TC_OK2MUNGE(n->tc_verd);
n->tc_verd = CLR_TC_MUNGED(n->tc_verd);
C(input_dev);
- C(tc_classid);
#endif
#endif
@@ -404,10 +447,8 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
*/
unsigned long offset = new->data - old->data;
- new->list = NULL;
new->sk = NULL;
new->dev = old->dev;
- new->real_dev = old->real_dev;
new->priority = old->priority;
new->protocol = old->protocol;
new->dst = dst_clone(old->dst);
@@ -419,12 +460,12 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
new->mac.raw = old->mac.raw + offset;
memcpy(new->cb, old->cb, sizeof(old->cb));
new->local_df = old->local_df;
+ new->fclone = SKB_FCLONE_UNAVAILABLE;
new->pkt_type = old->pkt_type;
- new->stamp = old->stamp;
+ new->tstamp = old->tstamp;
new->destructor = NULL;
#ifdef CONFIG_NETFILTER
new->nfmark = old->nfmark;
- new->nfcache = old->nfcache;
new->nfct = old->nfct;
nf_conntrack_get(old->nfct);
new->nfctinfo = old->nfctinfo;
@@ -1344,50 +1385,43 @@ void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk)
__skb_queue_tail(list, newsk);
spin_unlock_irqrestore(&list->lock, flags);
}
+
/**
* skb_unlink - remove a buffer from a list
* @skb: buffer to remove
+ * @list: list to use
*
- * Place a packet after a given packet in a list. The list locks are taken
- * and this function is atomic with respect to other list locked calls
+ * Remove a packet from a list. The list locks are taken and this
+ * function is atomic with respect to other list locked calls
*
- * Works even without knowing the list it is sitting on, which can be
- * handy at times. It also means that THE LIST MUST EXIST when you
- * unlink. Thus a list must have its contents unlinked before it is
- * destroyed.
+ * You must know what list the SKB is on.
*/
-void skb_unlink(struct sk_buff *skb)
+void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
{
- struct sk_buff_head *list = skb->list;
-
- if (list) {
- unsigned long flags;
+ unsigned long flags;
- spin_lock_irqsave(&list->lock, flags);
- if (skb->list == list)
- __skb_unlink(skb, skb->list);
- spin_unlock_irqrestore(&list->lock, flags);
- }
+ spin_lock_irqsave(&list->lock, flags);
+ __skb_unlink(skb, list);
+ spin_unlock_irqrestore(&list->lock, flags);
}
-
/**
* skb_append - append a buffer
* @old: buffer to insert after
* @newsk: buffer to insert
+ * @list: list to use
*
* Place a packet after a given packet in a list. The list locks are taken
* and this function is atomic with respect to other list locked calls.
* A buffer cannot be placed on two lists at the same time.
*/
-
-void skb_append(struct sk_buff *old, struct sk_buff *newsk)
+void skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list)
{
unsigned long flags;
- spin_lock_irqsave(&old->list->lock, flags);
- __skb_append(old, newsk);
- spin_unlock_irqrestore(&old->list->lock, flags);
+ spin_lock_irqsave(&list->lock, flags);
+ __skb_append(old, newsk, list);
+ spin_unlock_irqrestore(&list->lock, flags);
}
@@ -1395,19 +1429,21 @@ void skb_append(struct sk_buff *old, struct sk_buff *newsk)
* skb_insert - insert a buffer
* @old: buffer to insert before
* @newsk: buffer to insert
+ * @list: list to use
+ *
+ * Place a packet before a given packet in a list. The list locks are
+ * taken and this function is atomic with respect to other list locked
+ * calls.
*
- * Place a packet before a given packet in a list. The list locks are taken
- * and this function is atomic with respect to other list locked calls
* A buffer cannot be placed on two lists at the same time.
*/
-
-void skb_insert(struct sk_buff *old, struct sk_buff *newsk)
+void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list)
{
unsigned long flags;
- spin_lock_irqsave(&old->list->lock, flags);
- __skb_insert(newsk, old->prev, old, old->list);
- spin_unlock_irqrestore(&old->list->lock, flags);
+ spin_lock_irqsave(&list->lock, flags);
+ __skb_insert(newsk, old->prev, old, list);
+ spin_unlock_irqrestore(&list->lock, flags);
}
#if 0
@@ -1663,12 +1699,23 @@ void __init skb_init(void)
NULL, NULL);
if (!skbuff_head_cache)
panic("cannot create skbuff cache");
+
+ skbuff_fclone_cache = kmem_cache_create("skbuff_fclone_cache",
+ (2*sizeof(struct sk_buff)) +
+ sizeof(atomic_t),
+ 0,
+ SLAB_HWCACHE_ALIGN,
+ NULL, NULL);
+ if (!skbuff_fclone_cache)
+ panic("cannot create skbuff cache");
+
+ do_gettimeofday(&skb_tv_base);
}
EXPORT_SYMBOL(___pskb_trim);
EXPORT_SYMBOL(__kfree_skb);
EXPORT_SYMBOL(__pskb_pull_tail);
-EXPORT_SYMBOL(alloc_skb);
+EXPORT_SYMBOL(__alloc_skb);
EXPORT_SYMBOL(pskb_copy);
EXPORT_SYMBOL(pskb_expand_head);
EXPORT_SYMBOL(skb_checksum);
@@ -1696,3 +1743,4 @@ EXPORT_SYMBOL(skb_prepare_seq_read);
EXPORT_SYMBOL(skb_seq_read);
EXPORT_SYMBOL(skb_abort_seq_read);
EXPORT_SYMBOL(skb_find_text);
+EXPORT_SYMBOL(skb_tv_base);
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