diff options
| author | Ido Yariv <ido@wizery.com> | 2014-07-29 16:39:14 +0400 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2014-08-26 13:16:00 +0400 |
| commit | c70f59a2a007c57843195a93c3b7308204e0a5ab (patch) | |
| tree | db9426d7dbadd28f97c006b6426ac1e3cbca880c /net/mac80211/tx.c | |
| parent | ca34e3b5c808385b175650605faa29e71e91991b (diff) | |
| download | linux-c70f59a2a007c57843195a93c3b7308204e0a5ab.tar.xz | |
mac80211: don't resize skbs needlessly
Header-less cloned skbs with sufficient headroom need not be cloned
unless the tailroom is going to be modified.
Fix ieee80211_skb_resize so it would only resize cloned skbs if either
the header isn't released or the tailroom is going to be modified.
Some drivers might have assumed that skbs are never cloned, so add a HW
flag that explicitly permits cloned TX skbs. Drivers which do not modify
TX skbs should set this flag to avoid copying skbs.
Signed-off-by: Ido Yariv <idox.yariv@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'net/mac80211/tx.c')
| -rw-r--r-- | net/mac80211/tx.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 2051cc60f8ce..925c39f4099e 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1478,7 +1478,10 @@ static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata, tail_need = max_t(int, tail_need, 0); } - if (skb_cloned(skb)) + if (skb_cloned(skb) && + (!(local->hw.flags & IEEE80211_HW_SUPPORTS_CLONED_SKBS) || + !skb_clone_writable(skb, ETH_HLEN) || + sdata->crypto_tx_tailroom_needed_cnt)) I802_DEBUG_INC(local->tx_expand_skb_head_cloned); else if (head_need || tail_need) I802_DEBUG_INC(local->tx_expand_skb_head); |