Commit 49ddf8e6 authored by Johannes Berg's avatar Johannes Berg

mac80211: add fast-rx path

The regular RX path has a lot of code, but with a few
assumptions on the hardware it's possible to reduce the
amount of code significantly. Currently the assumptions
on the driver are the following:
 * hardware/driver reordering buffer (if supporting aggregation)
 * hardware/driver decryption & PN checking (if using encryption)
 * hardware/driver did de-duplication
 * hardware/driver did A-MSDU deaggregation
 * AP_LINK_PS is used (in AP mode)
 * no client powersave handling in mac80211 (in client mode)

of which some are actually checked per packet:
 * de-duplication
 * PN checking
 * decryption
and additionally packets must
 * not be A-MSDU (have been deaggregated by driver/device)
 * be data packets
 * not be fragmented
 * be unicast
 * have RFC 1042 header

Additionally dynamically we assume:
 * no encryption or CCMP/GCMP, TKIP/WEP/other not allowed
 * station must be authorized
 * 4-addr format not enabled

Some data needed for the RX path is cached in a new per-station
"fast_rx" structure, so that we only need to look at this and
the packet, no other memory when processing packets on the fast
RX path.

After doing the above per-packet checks, the data path collapses
down to a pretty simple conversion function taking advantage of
the data cached in the small fast_rx struct.

This should speed up the RX processing, and will make it easier
to reason about parallelizing RX (for which statistics will need
to be per-CPU still.)
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 0f9c5a61
...@@ -638,6 +638,16 @@ static inline bool ieee80211_is_first_frag(__le16 seq_ctrl) ...@@ -638,6 +638,16 @@ static inline bool ieee80211_is_first_frag(__le16 seq_ctrl)
return (seq_ctrl & cpu_to_le16(IEEE80211_SCTL_FRAG)) == 0; return (seq_ctrl & cpu_to_le16(IEEE80211_SCTL_FRAG)) == 0;
} }
/**
* ieee80211_is_frag - check if a frame is a fragment
* @hdr: 802.11 header of the frame
*/
static inline bool ieee80211_is_frag(struct ieee80211_hdr *hdr)
{
return ieee80211_has_morefrags(hdr->frame_control) ||
hdr->seq_ctrl & cpu_to_le16(IEEE80211_SCTL_FRAG);
}
struct ieee80211s_hdr { struct ieee80211s_hdr {
u8 flags; u8 flags;
u8 ttl; u8 ttl;
......
...@@ -65,11 +65,13 @@ static int ieee80211_change_iface(struct wiphy *wiphy, ...@@ -65,11 +65,13 @@ static int ieee80211_change_iface(struct wiphy *wiphy,
return ret; return ret;
if (type == NL80211_IFTYPE_AP_VLAN && if (type == NL80211_IFTYPE_AP_VLAN &&
params && params->use_4addr == 0) params && params->use_4addr == 0) {
RCU_INIT_POINTER(sdata->u.vlan.sta, NULL); RCU_INIT_POINTER(sdata->u.vlan.sta, NULL);
else if (type == NL80211_IFTYPE_STATION && ieee80211_check_fast_rx_iface(sdata);
params && params->use_4addr >= 0) } else if (type == NL80211_IFTYPE_STATION &&
params && params->use_4addr >= 0) {
sdata->u.mgd.use_4addr = params->use_4addr; sdata->u.mgd.use_4addr = params->use_4addr;
}
if (sdata->vif.type == NL80211_IFTYPE_MONITOR && flags) { if (sdata->vif.type == NL80211_IFTYPE_MONITOR && flags) {
struct ieee80211_local *local = sdata->local; struct ieee80211_local *local = sdata->local;
...@@ -1367,6 +1369,7 @@ static int ieee80211_change_station(struct wiphy *wiphy, ...@@ -1367,6 +1369,7 @@ static int ieee80211_change_station(struct wiphy *wiphy,
rcu_assign_pointer(vlansdata->u.vlan.sta, sta); rcu_assign_pointer(vlansdata->u.vlan.sta, sta);
new_4addr = true; new_4addr = true;
__ieee80211_check_fast_rx_iface(vlansdata);
} }
if (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && if (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
...@@ -1889,6 +1892,7 @@ static int ieee80211_change_bss(struct wiphy *wiphy, ...@@ -1889,6 +1892,7 @@ static int ieee80211_change_bss(struct wiphy *wiphy,
sdata->flags |= IEEE80211_SDATA_DONT_BRIDGE_PACKETS; sdata->flags |= IEEE80211_SDATA_DONT_BRIDGE_PACKETS;
else else
sdata->flags &= ~IEEE80211_SDATA_DONT_BRIDGE_PACKETS; sdata->flags &= ~IEEE80211_SDATA_DONT_BRIDGE_PACKETS;
ieee80211_check_fast_rx_iface(sdata);
} }
if (params->ht_opmode >= 0) { if (params->ht_opmode >= 0) {
......
...@@ -1494,6 +1494,11 @@ u64 ieee80211_mgmt_tx_cookie(struct ieee80211_local *local); ...@@ -1494,6 +1494,11 @@ u64 ieee80211_mgmt_tx_cookie(struct ieee80211_local *local);
int ieee80211_attach_ack_skb(struct ieee80211_local *local, struct sk_buff *skb, int ieee80211_attach_ack_skb(struct ieee80211_local *local, struct sk_buff *skb,
u64 *cookie, gfp_t gfp); u64 *cookie, gfp_t gfp);
void ieee80211_check_fast_rx(struct sta_info *sta);
void __ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata);
void ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata);
void ieee80211_clear_fast_rx(struct sta_info *sta);
/* STA code */ /* STA code */
void ieee80211_sta_setup_sdata(struct ieee80211_sub_if_data *sdata); void ieee80211_sta_setup_sdata(struct ieee80211_sub_if_data *sdata);
int ieee80211_mgd_auth(struct ieee80211_sub_if_data *sdata, int ieee80211_mgd_auth(struct ieee80211_sub_if_data *sdata,
......
...@@ -338,6 +338,7 @@ static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata, ...@@ -338,6 +338,7 @@ static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
} else { } else {
rcu_assign_pointer(sta->gtk[idx], new); rcu_assign_pointer(sta->gtk[idx], new);
} }
ieee80211_check_fast_rx(sta);
} else { } else {
defunikey = old && defunikey = old &&
old == key_mtx_dereference(sdata->local, old == key_mtx_dereference(sdata->local,
......
...@@ -2217,6 +2217,7 @@ static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata) ...@@ -2217,6 +2217,7 @@ static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata)
const u8 *ssid; const u8 *ssid;
u8 *dst = ifmgd->associated->bssid; u8 *dst = ifmgd->associated->bssid;
u8 unicast_limit = max(1, max_probe_tries - 3); u8 unicast_limit = max(1, max_probe_tries - 3);
struct sta_info *sta;
/* /*
* Try sending broadcast probe requests for the last three * Try sending broadcast probe requests for the last three
...@@ -2235,6 +2236,14 @@ static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata) ...@@ -2235,6 +2236,14 @@ static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata)
*/ */
ifmgd->probe_send_count++; ifmgd->probe_send_count++;
if (dst) {
mutex_lock(&sdata->local->sta_mtx);
sta = sta_info_get(sdata, dst);
if (!WARN_ON(!sta))
ieee80211_check_fast_rx(sta);
mutex_unlock(&sdata->local->sta_mtx);
}
if (ieee80211_hw_check(&sdata->local->hw, REPORTS_TX_ACK_STATUS)) { if (ieee80211_hw_check(&sdata->local->hw, REPORTS_TX_ACK_STATUS)) {
ifmgd->nullfunc_failed = false; ifmgd->nullfunc_failed = false;
ieee80211_send_nullfunc(sdata->local, sdata, false); ieee80211_send_nullfunc(sdata->local, sdata, false);
......
This diff is collapsed.
...@@ -1874,6 +1874,7 @@ int sta_info_move_state(struct sta_info *sta, ...@@ -1874,6 +1874,7 @@ int sta_info_move_state(struct sta_info *sta,
atomic_dec(&sta->sdata->bss->num_mcast_sta); atomic_dec(&sta->sdata->bss->num_mcast_sta);
clear_bit(WLAN_STA_AUTHORIZED, &sta->_flags); clear_bit(WLAN_STA_AUTHORIZED, &sta->_flags);
ieee80211_clear_fast_xmit(sta); ieee80211_clear_fast_xmit(sta);
ieee80211_clear_fast_rx(sta);
} }
break; break;
case IEEE80211_STA_AUTHORIZED: case IEEE80211_STA_AUTHORIZED:
...@@ -1884,6 +1885,7 @@ int sta_info_move_state(struct sta_info *sta, ...@@ -1884,6 +1885,7 @@ int sta_info_move_state(struct sta_info *sta,
atomic_inc(&sta->sdata->bss->num_mcast_sta); atomic_inc(&sta->sdata->bss->num_mcast_sta);
set_bit(WLAN_STA_AUTHORIZED, &sta->_flags); set_bit(WLAN_STA_AUTHORIZED, &sta->_flags);
ieee80211_check_fast_xmit(sta); ieee80211_check_fast_xmit(sta);
ieee80211_check_fast_rx(sta);
} }
break; break;
default: default:
......
...@@ -285,6 +285,38 @@ struct ieee80211_fast_tx { ...@@ -285,6 +285,38 @@ struct ieee80211_fast_tx {
struct rcu_head rcu_head; struct rcu_head rcu_head;
}; };
/**
* struct ieee80211_fast_rx - RX fastpath information
* @dev: netdevice for reporting the SKB
* @vif_type: (P2P-less) interface type of the original sdata (sdata->vif.type)
* @vif_addr: interface address
* @rfc1042_hdr: copy of the RFC 1042 SNAP header (to have in cache)
* @control_port_protocol: control port protocol copied from sdata
* @expected_ds_bits: from/to DS bits expected
* @icv_len: length of the MIC if present
* @key: bool indicating encryption is expected (key is set)
* @sta_notify: notify the MLME code (once)
* @internal_forward: forward froms internally on AP/VLAN type interfaces
* @da_offs: offset of the DA in the header (for header conversion)
* @sa_offs: offset of the SA in the header (for header conversion)
* @rcu_head: RCU head for freeing this structure
*/
struct ieee80211_fast_rx {
struct net_device *dev;
enum nl80211_iftype vif_type;
u8 vif_addr[ETH_ALEN] __aligned(2);
u8 rfc1042_hdr[6] __aligned(2);
__be16 control_port_protocol;
__le16 expected_ds_bits;
u8 icv_len;
u8 key:1,
sta_notify:1,
internal_forward:1;
u8 da_offs, sa_offs;
struct rcu_head rcu_head;
};
/** /**
* struct mesh_sta - mesh STA information * struct mesh_sta - mesh STA information
* @plink_lock: serialize access to plink fields * @plink_lock: serialize access to plink fields
...@@ -391,6 +423,7 @@ DECLARE_EWMA(signal, 1024, 8) ...@@ -391,6 +423,7 @@ DECLARE_EWMA(signal, 1024, 8)
* @cipher_scheme: optional cipher scheme for this station * @cipher_scheme: optional cipher scheme for this station
* @reserved_tid: reserved TID (if any, otherwise IEEE80211_TID_UNRESERVED) * @reserved_tid: reserved TID (if any, otherwise IEEE80211_TID_UNRESERVED)
* @fast_tx: TX fastpath information * @fast_tx: TX fastpath information
* @fast_rx: RX fastpath information
* @tdls_chandef: a TDLS peer can have a wider chandef that is compatible to * @tdls_chandef: a TDLS peer can have a wider chandef that is compatible to
* the BSS one. * the BSS one.
* @tx_stats: TX statistics * @tx_stats: TX statistics
...@@ -414,6 +447,7 @@ struct sta_info { ...@@ -414,6 +447,7 @@ struct sta_info {
spinlock_t lock; spinlock_t lock;
struct ieee80211_fast_tx __rcu *fast_tx; struct ieee80211_fast_tx __rcu *fast_tx;
struct ieee80211_fast_rx __rcu *fast_rx;
#ifdef CONFIG_MAC80211_MESH #ifdef CONFIG_MAC80211_MESH
struct mesh_sta *mesh; struct mesh_sta *mesh;
......
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