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>
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 4d085d4..17e4b1e 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -932,7 +932,6 @@
u8 *data;
int size = nhead + (skb_end_pointer(skb) - skb->head) + ntail;
long off;
- bool fastpath;
BUG_ON(nhead < 0);
@@ -941,16 +940,6 @@
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 @@
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 @@
skb_clone_fraglist(skb);
skb_release_data(skb);
+ } else {
+ skb_free_head(skb);
}
off = (data + nhead) - skb->head;