diff options
| author | Eric Dumazet <edumazet@google.com> | 2014-10-03 20:59:19 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-10-06 00:37:30 -0400 |
| commit | bec3cfdca36bf43cfa3751ad7b56db1a307e0760 (patch) | |
| tree | d9c2d8352b0cc41d43dc23b7a7eafdac6758aeb3 /net | |
| parent | 45d9cc7c609680e921060d3eb4e399043eb5e4be (diff) | |
| download | linux-bec3cfdca36bf43cfa3751ad7b56db1a307e0760.tar.gz linux-bec3cfdca36bf43cfa3751ad7b56db1a307e0760.tar.bz2 linux-bec3cfdca36bf43cfa3751ad7b56db1a307e0760.zip | |
net: skb_segment() provides list head and tail
Its unfortunate we have to walk again skb list to find the tail
after segmentation, even if data is probably hot in cpu caches.
skb_segment() can store the tail of the list into segs->prev,
and validate_xmit_skb_list() can immediately get the tail.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/dev.c | 27 | ||||
| -rw-r--r-- | net/core/skbuff.c | 5 |
2 files changed, 20 insertions, 12 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 1a90530f83ff..7d5691cc1f47 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2724,22 +2724,25 @@ struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *d { struct sk_buff *next, *head = NULL, *tail; - while (skb) { + for (; skb != NULL; skb = next) { next = skb->next; skb->next = NULL; + + /* in case skb wont be segmented, point to itself */ + skb->prev = skb; + skb = validate_xmit_skb(skb, dev); - if (skb) { - struct sk_buff *end = skb; + if (!skb) + continue; - while (end->next) - end = end->next; - if (!head) - head = skb; - else - tail->next = skb; - tail = end; - } - skb = next; + if (!head) + head = skb; + else + tail->next = skb; + /* If skb was segmented, skb->prev points to + * the last segment. If not, it still contains skb. + */ + tail = skb->prev; } return head; } diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 9a423e2c5766..7b3df0d518ab 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3083,6 +3083,11 @@ perform_csum_check: } } while ((offset += len) < head_skb->len); + /* Some callers want to get the end of the list. + * Put it in segs->prev to avoid walking the list. + * (see validate_xmit_skb_list() for example) + */ + segs->prev = tail; return segs; err: |