diff mbox

[1/4] mac80211: don't look up destination station twice

Message ID 1426865064-17707-2-git-send-email-johannes@sipsolutions.net (mailing list archive)
State Accepted
Delegated to: Johannes Berg
Headers show

Commit Message

Johannes Berg March 20, 2015, 3:24 p.m. UTC 
From: Johannes Berg <johannes.berg@intel.com>

There's no need to look up the destination station twice while
building the 802.11 header for a given frame if the frame will
actually be transmitted to the station we initially looked up.

This happens for 4-addr VLAN interfaces and TDLS connections, which
both directly send the frame to the station they looked up, though
in the case of TDLS some station conditions need to be checked.

To avoid that, add a variable indicating that we've looked up the
station that the frame is going to be transmitted to, and avoid the
lookup/flag checking if it already has been done.

In the TDLS case, also move the authorized/wme_sta flag assignment
to the correct place, i.e. only when that station is really used.
Before this change, the new lookup should always have succeeded so
that the potentially erroneous data would be overwritten.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/mac80211/tx.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

Comments

Arik Nemtsov March 22, 2015, 7:37 a.m. UTC | #1 
On Fri, Mar 20, 2015 at 5:24 PM, Johannes Berg
<johannes@sipsolutions.net> wrote:
> From: Johannes Berg <johannes.berg@intel.com>
>
> There's no need to look up the destination station twice while
> building the 802.11 header for a given frame if the frame will
> actually be transmitted to the station we initially looked up.
>
> This happens for 4-addr VLAN interfaces and TDLS connections, which
> both directly send the frame to the station they looked up, though
> in the case of TDLS some station conditions need to be checked.
>
> To avoid that, add a variable indicating that we've looked up the
> station that the frame is going to be transmitted to, and avoid the
> lookup/flag checking if it already has been done.
>
> In the TDLS case, also move the authorized/wme_sta flag assignment
> to the correct place, i.e. only when that station is really used.
> Before this change, the new lookup should always have succeeded so
> that the potentially erroneous data would be overwritten.
>
> Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The TDLS parts look good.

Arik
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diff mbox

Patch

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 0bae03bca49e..dcf60ee38b93 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1816,6 +1816,7 @@  static struct sk_buff *ieee80211_build_hdr(struct ieee80211_sub_if_data *sdata,
 	bool wme_sta = false, authorized = false, tdls_auth = false;
 	bool tdls_peer = false, tdls_setup_frame = false;
 	bool multicast;
+	bool have_station = false;
 	u16 info_id = 0;
 	struct ieee80211_chanctx_conf *chanctx_conf;
 	struct ieee80211_sub_if_data *ap_sdata;
@@ -1840,6 +1841,7 @@  static struct sk_buff *ieee80211_build_hdr(struct ieee80211_sub_if_data *sdata,
 			hdrlen = 30;
 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
 			wme_sta = sta->sta.wme;
+			have_station = true;
 		}
 		ap_sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
 					u.ap);
@@ -1956,9 +1958,6 @@  static struct sk_buff *ieee80211_build_hdr(struct ieee80211_sub_if_data *sdata,
 		if (sdata->wdev.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS) {
 			sta = sta_info_get(sdata, skb->data);
 			if (sta) {
-				authorized = test_sta_flag(sta,
-							WLAN_STA_AUTHORIZED);
-				wme_sta = sta->sta.wme;
 				tdls_peer = test_sta_flag(sta,
 							  WLAN_STA_TDLS_PEER);
 				tdls_auth = test_sta_flag(sta,
@@ -1990,6 +1989,9 @@  static struct sk_buff *ieee80211_build_hdr(struct ieee80211_sub_if_data *sdata,
 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 			memcpy(hdr.addr3, sdata->u.mgd.bssid, ETH_ALEN);
 			hdrlen = 24;
+			have_station = true;
+			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
+			wme_sta = sta->sta.wme;
 		}  else if (sdata->u.mgd.use_4addr &&
 			    cpu_to_be16(ethertype) != sdata->control_port_protocol) {
 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
@@ -2052,7 +2054,7 @@  static struct sk_buff *ieee80211_build_hdr(struct ieee80211_sub_if_data *sdata,
 	 * in AP mode)
 	 */
 	multicast = is_multicast_ether_addr(hdr.addr1);
-	if (!multicast) {
+	if (!multicast && !have_station) {
 		sta = sta_info_get(sdata, hdr.addr1);
 		if (sta) {
 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);