diff options
| author | Eric Dumazet <edumazet@google.com> | 2012-07-10 10:03:41 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-07-10 23:33:12 -0700 |
| commit | b28ba72665356438e3a6e3be365c3c3071496840 (patch) | |
| tree | 2cf9ff84993f821cd4819db7dd609db1ccbf38f6 /drivers | |
| parent | efc73f4bbc238d4f579fb612c04c8e1dd8a82979 (diff) | |
| download | linux-b28ba72665356438e3a6e3be365c3c3071496840.tar.bz2 | |
IPoIB: fix skb truesize underestimatiom
Or Gerlitz reported triggering of WARN_ON_ONCE(delta < len); in
skb_try_coalesce()
This warning tracks drivers that incorrectly set skb->truesize
IPoIB indeed allocates a full page to store a fragment, but only
accounts in skb->truesize the used part of the page (frame length)
This patch fixes skb truesize underestimation, and
also fixes a performance issue, because RX skbs have not enough tailroom
to allow IP and TCP stacks to pull their header in skb linear part
without an expensive call to pskb_expand_head()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Erez Shitrit <erezsh@mellanox.com>
Cc: Shlomo Pongartz <shlomop@mellanox.com>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/infiniband/ulp/ipoib/ipoib_ib.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c index 5c1bc995e560..f10221f40803 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c @@ -123,7 +123,7 @@ static void ipoib_ud_skb_put_frags(struct ipoib_dev_priv *priv, skb_frag_size_set(frag, size); skb->data_len += size; - skb->truesize += size; + skb->truesize += PAGE_SIZE; } else skb_put(skb, length); @@ -156,14 +156,18 @@ static struct sk_buff *ipoib_alloc_rx_skb(struct net_device *dev, int id) struct ipoib_dev_priv *priv = netdev_priv(dev); struct sk_buff *skb; int buf_size; + int tailroom; u64 *mapping; - if (ipoib_ud_need_sg(priv->max_ib_mtu)) + if (ipoib_ud_need_sg(priv->max_ib_mtu)) { buf_size = IPOIB_UD_HEAD_SIZE; - else + tailroom = 128; /* reserve some tailroom for IP/TCP headers */ + } else { buf_size = IPOIB_UD_BUF_SIZE(priv->max_ib_mtu); + tailroom = 0; + } - skb = dev_alloc_skb(buf_size + 4); + skb = dev_alloc_skb(buf_size + tailroom + 4); if (unlikely(!skb)) return NULL; |