skb: Drop "fastpath" variable for skb_cloned check in pskb_expand_head

Since there is now only one spot that actually uses "fastpath" there isn't
much point in carrying it.  Instead we can just use a check for skb_cloned
to verify if we can perform the fast-path free for the head or not.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alexander Duyck 2012-05-04 14:26:51 +00:00 committed by David S. Miller
parent 9202e31d46
commit 3e24591a19

View File

@ -932,7 +932,6 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
u8 *data;
int size = nhead + (skb_end_pointer(skb) - skb->head) + ntail;
long off;
bool fastpath;
BUG_ON(nhead < 0);
@ -941,16 +940,6 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
size = SKB_DATA_ALIGN(size);
/* Check if we can avoid taking references on fragments if we own
* the last reference on skb->head. (see skb_release_data())
*/
if (!skb->cloned)
fastpath = true;
else {
int delta = skb->nohdr ? (1 << SKB_DATAREF_SHIFT) + 1 : 1;
fastpath = atomic_read(&skb_shinfo(skb)->dataref) == delta;
}
data = kmalloc(size + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)),
gfp_mask);
if (!data)
@ -966,9 +955,12 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
skb_shinfo(skb),
offsetof(struct skb_shared_info, frags[skb_shinfo(skb)->nr_frags]));
if (fastpath) {
skb_free_head(skb);
} else {
/*
* if shinfo is shared we must drop the old head gracefully, but if it
* is not we can just drop the old head and let the existing refcount
* be since all we did is relocate the values
*/
if (skb_cloned(skb)) {
/* copy this zero copy skb frags */
if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) {
if (skb_copy_ubufs(skb, gfp_mask))
@ -981,6 +973,8 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
skb_clone_fraglist(skb);
skb_release_data(skb);
} else {
skb_free_head(skb);
}
off = (data + nhead) - skb->head;