mac80211: optimize tx status processing

When a cooked monitor interface is active, ieee80211_tx_status()
generates a radiotap header for every single frame, even if it wasn't
injected and thus won't be sent to a monitor interface.
This patch reduces cpu utilization by moving the cooked monitor check a
bit earlier, before it generates the rtap header.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Felix Fietkau 2010-03-11 16:28:24 +01:00 committed by John W. Linville
parent 819cf15e7c
commit eaf55530c9

View File

@ -171,7 +171,7 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
struct net_device *prev_dev = NULL;
struct sta_info *sta, *tmp;
int retry_count = -1, i;
bool injected;
bool send_to_cooked;
for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
/* the HW cannot have attempted that rate */
@ -296,11 +296,15 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
/* this was a transmitted frame, but now we want to reuse it */
skb_orphan(skb);
/* Need to make a copy before skb->cb gets cleared */
send_to_cooked = !!(info->flags & IEEE80211_TX_CTL_INJECTED) ||
(type != IEEE80211_FTYPE_DATA);
/*
* This is a bit racy but we can avoid a lot of work
* with this test...
*/
if (!local->monitors && !local->cooked_mntrs) {
if (!local->monitors && (!send_to_cooked || !local->cooked_mntrs)) {
dev_kfree_skb(skb);
return;
}
@ -345,9 +349,6 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
/* for now report the total retry_count */
rthdr->data_retries = retry_count;
/* Need to make a copy before skb->cb gets cleared */
injected = !!(info->flags & IEEE80211_TX_CTL_INJECTED);
/* XXX: is this sufficient for BPF? */
skb_set_mac_header(skb, 0);
skb->ip_summed = CHECKSUM_UNNECESSARY;
@ -362,8 +363,7 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
continue;
if ((sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) &&
!injected &&
(type == IEEE80211_FTYPE_DATA))
!send_to_cooked)
continue;
if (prev_dev) {