From: Ben Greear Date: Fri, 4 Feb 2011 19:54:17 +0000 (-0800) Subject: mac80211: Optimize scans on current operating channel. X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=b23b025fe246f3acc2988eb6d400df34c27cb8ae;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git mac80211: Optimize scans on current operating channel. This should decrease un-necessary flushes, on/off channel work, and channel changes in cases where the only scanned channel is the current operating channel. * Removes SCAN_OFF_CHANNEL flag, uses SDATA_STATE_OFFCHANNEL and is-scanning flags instead. * Add helper method to determine if we are currently configured for the operating channel. * Do no blindly go off/on channel in work.c Instead, only call appropriate on/off code when we really need to change channels. Always enable offchannel-ps mode when starting work, and disable it when we are done. * Consolidate ieee80211_offchannel_stop_station and ieee80211_offchannel_stop_beaconing, call it ieee80211_offchannel_stop_vifs instead. * Accept non-beacon frames when scanning on operating channel. * Scan state machine optimized to minimize on/off channel transitions. Also, when going on-channel, go ahead and re-enable beaconing. We're going to be there for 200ms, so seems like some useful beaconing could happen. Always enable offchannel-ps mode when starting software scan, and disable it when we are done. * Grab local->mtx earlier in __ieee80211_scan_completed_finish so that we are protected when calling hw_config(), etc. * Pass probe-responses up the stack if scanning on local channel, so that mlme can take a look. Signed-off-by: Ben Greear Signed-off-by: John W. Linville --- diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index f71ed31d176a..44eea1af1553 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -655,8 +655,6 @@ struct tpt_led_trigger { * well be on the operating channel * @SCAN_HW_SCANNING: The hardware is scanning for us, we have no way to * determine if we are on the operating channel or not - * @SCAN_OFF_CHANNEL: We're off our operating channel for scanning, - * gets only set in conjunction with SCAN_SW_SCANNING * @SCAN_COMPLETED: Set for our scan work function when the driver reported * that the scan completed. * @SCAN_ABORTED: Set for our scan work function when the driver reported @@ -665,7 +663,6 @@ struct tpt_led_trigger { enum { SCAN_SW_SCANNING, SCAN_HW_SCANNING, - SCAN_OFF_CHANNEL, SCAN_COMPLETED, SCAN_ABORTED, }; @@ -1148,10 +1145,14 @@ void ieee80211_rx_bss_put(struct ieee80211_local *local, struct ieee80211_bss *bss); /* off-channel helpers */ -void ieee80211_offchannel_stop_beaconing(struct ieee80211_local *local); -void ieee80211_offchannel_stop_station(struct ieee80211_local *local); +bool ieee80211_cfg_on_oper_channel(struct ieee80211_local *local); +void ieee80211_offchannel_enable_all_ps(struct ieee80211_local *local, + bool tell_ap); +void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local, + bool offchannel_ps_enable); void ieee80211_offchannel_return(struct ieee80211_local *local, - bool enable_beaconing); + bool enable_beaconing, + bool offchannel_ps_disable); void ieee80211_hw_roc_setup(struct ieee80211_local *local); /* interface handling */ diff --git a/net/mac80211/main.c b/net/mac80211/main.c index 09a27449f3fd..c155c0b69426 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -98,6 +98,41 @@ static void ieee80211_reconfig_filter(struct work_struct *work) ieee80211_configure_filter(local); } +/* + * Returns true if we are logically configured to be on + * the operating channel AND the hardware-conf is currently + * configured on the operating channel. Compares channel-type + * as well. + */ +bool ieee80211_cfg_on_oper_channel(struct ieee80211_local *local) +{ + struct ieee80211_channel *chan, *scan_chan; + enum nl80211_channel_type channel_type; + + /* This logic needs to match logic in ieee80211_hw_config */ + if (local->scan_channel) { + chan = local->scan_channel; + channel_type = NL80211_CHAN_NO_HT; + } else if (local->tmp_channel) { + chan = scan_chan = local->tmp_channel; + channel_type = local->tmp_channel_type; + } else { + chan = local->oper_channel; + channel_type = local->_oper_channel_type; + } + + if (chan != local->oper_channel || + channel_type != local->_oper_channel_type) + return false; + + /* Check current hardware-config against oper_channel. */ + if ((local->oper_channel != local->hw.conf.channel) || + (local->_oper_channel_type != local->hw.conf.channel_type)) + return false; + + return true; +} + int ieee80211_hw_config(struct ieee80211_local *local, u32 changed) { struct ieee80211_channel *chan, *scan_chan; @@ -110,21 +145,27 @@ int ieee80211_hw_config(struct ieee80211_local *local, u32 changed) scan_chan = local->scan_channel; + /* If this off-channel logic ever changes, ieee80211_on_oper_channel + * may need to change as well. + */ offchannel_flag = local->hw.conf.flags & IEEE80211_CONF_OFFCHANNEL; if (scan_chan) { chan = scan_chan; channel_type = NL80211_CHAN_NO_HT; - local->hw.conf.flags |= IEEE80211_CONF_OFFCHANNEL; - } else if (local->tmp_channel && - local->oper_channel != local->tmp_channel) { + } else if (local->tmp_channel) { chan = scan_chan = local->tmp_channel; channel_type = local->tmp_channel_type; - local->hw.conf.flags |= IEEE80211_CONF_OFFCHANNEL; } else { chan = local->oper_channel; channel_type = local->_oper_channel_type; - local->hw.conf.flags &= ~IEEE80211_CONF_OFFCHANNEL; } + + if (chan != local->oper_channel || + channel_type != local->_oper_channel_type) + local->hw.conf.flags |= IEEE80211_CONF_OFFCHANNEL; + else + local->hw.conf.flags &= ~IEEE80211_CONF_OFFCHANNEL; + offchannel_flag ^= local->hw.conf.flags & IEEE80211_CONF_OFFCHANNEL; if (offchannel_flag || chan != local->hw.conf.channel || @@ -231,7 +272,7 @@ void ieee80211_bss_info_change_notify(struct ieee80211_sub_if_data *sdata, if (changed & BSS_CHANGED_BEACON_ENABLED) { if (local->quiescing || !ieee80211_sdata_running(sdata) || - test_bit(SCAN_SW_SCANNING, &local->scanning)) { + test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state)) { sdata->vif.bss_conf.enable_beacon = false; } else { /* diff --git a/net/mac80211/offchannel.c b/net/mac80211/offchannel.c index b4e52676f3fb..13427b194ced 100644 --- a/net/mac80211/offchannel.c +++ b/net/mac80211/offchannel.c @@ -17,10 +17,14 @@ #include "driver-trace.h" /* - * inform AP that we will go to sleep so that it will buffer the frames - * while we scan + * Tell our hardware to disable PS. + * Optionally inform AP that we will go to sleep so that it will buffer + * the frames while we are doing off-channel work. This is optional + * because we *may* be doing work on-operating channel, and want our + * hardware unconditionally awake, but still let the AP send us normal frames. */ -static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata) +static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata, + bool tell_ap) { struct ieee80211_local *local = sdata->local; struct ieee80211_if_managed *ifmgd = &sdata->u.mgd; @@ -41,8 +45,8 @@ static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata) ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); } - if (!(local->offchannel_ps_enabled) || - !(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)) + if (tell_ap && (!local->offchannel_ps_enabled || + !(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK))) /* * If power save was enabled, no need to send a nullfunc * frame because AP knows that we are sleeping. But if the @@ -77,6 +81,9 @@ static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata) * we are sleeping, let's just enable power save mode in * hardware. */ + /* TODO: Only set hardware if CONF_PS changed? + * TODO: Should we set offchannel_ps_enabled to false? + */ local->hw.conf.flags |= IEEE80211_CONF_PS; ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); } else if (local->hw.conf.dynamic_ps_timeout > 0) { @@ -95,63 +102,61 @@ static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata) ieee80211_sta_reset_conn_monitor(sdata); } -void ieee80211_offchannel_stop_beaconing(struct ieee80211_local *local) +void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local, + bool offchannel_ps_enable) { struct ieee80211_sub_if_data *sdata; + /* + * notify the AP about us leaving the channel and stop all + * STA interfaces. + */ mutex_lock(&local->iflist_mtx); list_for_each_entry(sdata, &local->interfaces, list) { if (!ieee80211_sdata_running(sdata)) continue; - /* disable beaconing */ + if (sdata->vif.type != NL80211_IFTYPE_MONITOR) + set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state); + + /* Check to see if we should disable beaconing. */ if (sdata->vif.type == NL80211_IFTYPE_AP || sdata->vif.type == NL80211_IFTYPE_ADHOC || sdata->vif.type == NL80211_IFTYPE_MESH_POINT) ieee80211_bss_info_change_notify( sdata, BSS_CHANGED_BEACON_ENABLED); - /* - * only handle non-STA interfaces here, STA interfaces - * are handled in ieee80211_offchannel_stop_station(), - * e.g., from the background scan state machine. - * - * In addition, do not stop monitor interface to allow it to be - * used from user space controlled off-channel operations. - */ - if (sdata->vif.type != NL80211_IFTYPE_STATION && - sdata->vif.type != NL80211_IFTYPE_MONITOR) { - set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state); + if (sdata->vif.type != NL80211_IFTYPE_MONITOR) { netif_tx_stop_all_queues(sdata->dev); + if (offchannel_ps_enable && + (sdata->vif.type == NL80211_IFTYPE_STATION) && + sdata->u.mgd.associated) + ieee80211_offchannel_ps_enable(sdata, true); } } mutex_unlock(&local->iflist_mtx); } -void ieee80211_offchannel_stop_station(struct ieee80211_local *local) +void ieee80211_offchannel_enable_all_ps(struct ieee80211_local *local, + bool tell_ap) { struct ieee80211_sub_if_data *sdata; - /* - * notify the AP about us leaving the channel and stop all STA interfaces - */ mutex_lock(&local->iflist_mtx); list_for_each_entry(sdata, &local->interfaces, list) { if (!ieee80211_sdata_running(sdata)) continue; - if (sdata->vif.type == NL80211_IFTYPE_STATION) { - set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state); - netif_tx_stop_all_queues(sdata->dev); - if (sdata->u.mgd.associated) - ieee80211_offchannel_ps_enable(sdata); - } + if (sdata->vif.type == NL80211_IFTYPE_STATION && + sdata->u.mgd.associated) + ieee80211_offchannel_ps_enable(sdata, tell_ap); } mutex_unlock(&local->iflist_mtx); } void ieee80211_offchannel_return(struct ieee80211_local *local, - bool enable_beaconing) + bool enable_beaconing, + bool offchannel_ps_disable) { struct ieee80211_sub_if_data *sdata; @@ -161,7 +166,8 @@ void ieee80211_offchannel_return(struct ieee80211_local *local, continue; /* Tell AP we're back */ - if (sdata->vif.type == NL80211_IFTYPE_STATION) { + if (offchannel_ps_disable && + sdata->vif.type == NL80211_IFTYPE_STATION) { if (sdata->u.mgd.associated) ieee80211_offchannel_ps_disable(sdata); } @@ -181,7 +187,7 @@ void ieee80211_offchannel_return(struct ieee80211_local *local, netif_tx_wake_all_queues(sdata->dev); } - /* re-enable beaconing */ + /* Check to see if we should re-enable beaconing */ if (enable_beaconing && (sdata->vif.type == NL80211_IFTYPE_AP || sdata->vif.type == NL80211_IFTYPE_ADHOC || diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 753ffc41c1aa..b5f59ed24000 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -409,16 +409,10 @@ ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx) if (likely(!(status->rx_flags & IEEE80211_RX_IN_SCAN))) return RX_CONTINUE; - if (test_bit(SCAN_HW_SCANNING, &local->scanning)) + if (test_bit(SCAN_HW_SCANNING, &local->scanning) || + test_bit(SCAN_SW_SCANNING, &local->scanning)) return ieee80211_scan_rx(rx->sdata, skb); - if (test_bit(SCAN_SW_SCANNING, &local->scanning)) { - /* drop all the other packets during a software scan anyway */ - if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED) - dev_kfree_skb(skb); - return RX_QUEUED; - } - /* scanning finished during invoking of handlers */ I802_DEBUG_INC(local->rx_handlers_drop_passive_scan); return RX_DROP_UNUSABLE; @@ -2793,7 +2787,7 @@ static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, local->dot11ReceivedFragmentCount++; if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) || - test_bit(SCAN_OFF_CHANNEL, &local->scanning))) + test_bit(SCAN_SW_SCANNING, &local->scanning))) status->rx_flags |= IEEE80211_RX_IN_SCAN; if (ieee80211_is_mgmt(fc)) diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c index 1ef73be76b25..0ea6adae3e06 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -212,6 +212,14 @@ ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) if (bss) ieee80211_rx_bss_put(sdata->local, bss); + /* If we are on-operating-channel, and this packet is for the + * current channel, pass the pkt on up the stack so that + * the rest of the stack can make use of it. + */ + if (ieee80211_cfg_on_oper_channel(sdata->local) + && (channel == sdata->local->oper_channel)) + return RX_CONTINUE; + dev_kfree_skb(skb); return RX_QUEUED; } @@ -293,15 +301,31 @@ static void __ieee80211_scan_completed_finish(struct ieee80211_hw *hw, bool was_hw_scan) { struct ieee80211_local *local = hw_to_local(hw); + bool on_oper_chan; + bool enable_beacons = false; + + mutex_lock(&local->mtx); + on_oper_chan = ieee80211_cfg_on_oper_channel(local); + + if (was_hw_scan || !on_oper_chan) { + if (WARN_ON(local->scan_channel)) + local->scan_channel = NULL; + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); + } - ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); if (!was_hw_scan) { + bool on_oper_chan2; ieee80211_configure_filter(local); drv_sw_scan_complete(local); - ieee80211_offchannel_return(local, true); + on_oper_chan2 = ieee80211_cfg_on_oper_channel(local); + /* We should always be on-channel at this point. */ + WARN_ON(!on_oper_chan2); + if (on_oper_chan2 && (on_oper_chan != on_oper_chan2)) + enable_beacons = true; + + ieee80211_offchannel_return(local, enable_beacons, true); } - mutex_lock(&local->mtx); ieee80211_recalc_idle(local); mutex_unlock(&local->mtx); @@ -341,13 +365,15 @@ static int ieee80211_start_sw_scan(struct ieee80211_local *local) */ drv_sw_scan_start(local); - ieee80211_offchannel_stop_beaconing(local); - local->leave_oper_channel_time = 0; local->next_scan_state = SCAN_DECISION; local->scan_channel_idx = 0; - drv_flush(local, false); + /* We always want to use off-channel PS, even if we + * are not really leaving oper-channel. Don't + * tell the AP though, as long as we are on-channel. + */ + ieee80211_offchannel_enable_all_ps(local, false); ieee80211_configure_filter(local); @@ -487,7 +513,21 @@ static void ieee80211_scan_state_decision(struct ieee80211_local *local, } mutex_unlock(&local->iflist_mtx); - if (local->scan_channel) { + next_chan = local->scan_req->channels[local->scan_channel_idx]; + + if (ieee80211_cfg_on_oper_channel(local)) { + /* We're currently on operating channel. */ + if ((next_chan == local->oper_channel) && + (local->_oper_channel_type == NL80211_CHAN_NO_HT)) + /* We don't need to move off of operating channel. */ + local->next_scan_state = SCAN_SET_CHANNEL; + else + /* + * We do need to leave operating channel, as next + * scan is somewhere else. + */ + local->next_scan_state = SCAN_LEAVE_OPER_CHANNEL; + } else { /* * we're currently scanning a different channel, let's * see if we can scan another channel without interfering @@ -503,7 +543,6 @@ static void ieee80211_scan_state_decision(struct ieee80211_local *local, * * Otherwise switch back to the operating channel. */ - next_chan = local->scan_req->channels[local->scan_channel_idx]; bad_latency = time_after(jiffies + ieee80211_scan_get_channel_time(next_chan), @@ -521,12 +560,6 @@ static void ieee80211_scan_state_decision(struct ieee80211_local *local, local->next_scan_state = SCAN_ENTER_OPER_CHANNEL; else local->next_scan_state = SCAN_SET_CHANNEL; - } else { - /* - * we're on the operating channel currently, let's - * leave that channel now to scan another one - */ - local->next_scan_state = SCAN_LEAVE_OPER_CHANNEL; } *next_delay = 0; @@ -535,9 +568,10 @@ static void ieee80211_scan_state_decision(struct ieee80211_local *local, static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local *local, unsigned long *next_delay) { - ieee80211_offchannel_stop_station(local); - - __set_bit(SCAN_OFF_CHANNEL, &local->scanning); + /* PS will already be in off-channel mode, + * we do that once at the beginning of scanning. + */ + ieee80211_offchannel_stop_vifs(local, false); /* * What if the nullfunc frames didn't arrive? @@ -560,15 +594,15 @@ static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local *loca { /* switch back to the operating channel */ local->scan_channel = NULL; - ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); + if (!ieee80211_cfg_on_oper_channel(local)) + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); /* - * Only re-enable station mode interface now; beaconing will be - * re-enabled once the full scan has been completed. + * Re-enable vifs and beaconing. Leave PS + * in off-channel state..will put that back + * on-channel at the end of scanning. */ - ieee80211_offchannel_return(local, false); - - __clear_bit(SCAN_OFF_CHANNEL, &local->scanning); + ieee80211_offchannel_return(local, true, false); *next_delay = HZ / 5; local->next_scan_state = SCAN_DECISION; @@ -584,8 +618,12 @@ static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, chan = local->scan_req->channels[local->scan_channel_idx]; local->scan_channel = chan; - if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) - skip = 1; + + /* Only call hw-config if we really need to change channels. */ + if ((chan != local->hw.conf.channel) || + (local->hw.conf.channel_type != NL80211_CHAN_NO_HT)) + if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) + skip = 1; /* advance state machine to next channel/band */ local->scan_channel_idx++; diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index bf67a223cd60..291516807fc4 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -257,7 +257,8 @@ ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx) if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) return TX_CONTINUE; - if (unlikely(test_bit(SCAN_OFF_CHANNEL, &tx->local->scanning)) && + if (unlikely(test_bit(SCAN_SW_SCANNING, &tx->local->scanning)) && + test_bit(SDATA_STATE_OFFCHANNEL, &tx->sdata->state) && !ieee80211_is_probe_req(hdr->frame_control) && !ieee80211_is_nullfunc(hdr->frame_control)) /* diff --git a/net/mac80211/work.c b/net/mac80211/work.c index 36305e0d06ef..6bf787a5b38a 100644 --- a/net/mac80211/work.c +++ b/net/mac80211/work.c @@ -924,18 +924,44 @@ static void ieee80211_work_work(struct work_struct *work) } if (!started && !local->tmp_channel) { - /* - * TODO: could optimize this by leaving the - * station vifs in awake mode if they - * happen to be on the same channel as - * the requested channel - */ - ieee80211_offchannel_stop_beaconing(local); - ieee80211_offchannel_stop_station(local); + bool on_oper_chan; + bool tmp_chan_changed = false; + bool on_oper_chan2; + on_oper_chan = ieee80211_cfg_on_oper_channel(local); + if (local->tmp_channel) + if ((local->tmp_channel != wk->chan) || + (local->tmp_channel_type != wk->chan_type)) + tmp_chan_changed = true; local->tmp_channel = wk->chan; local->tmp_channel_type = wk->chan_type; - ieee80211_hw_config(local, 0); + /* + * Leave the station vifs in awake mode if they + * happen to be on the same channel as + * the requested channel. + */ + on_oper_chan2 = ieee80211_cfg_on_oper_channel(local); + if (on_oper_chan != on_oper_chan2) { + if (on_oper_chan2) { + /* going off oper channel, PS too */ + ieee80211_offchannel_stop_vifs(local, + true); + ieee80211_hw_config(local, 0); + } else { + /* going on channel, but leave PS + * off-channel. */ + ieee80211_hw_config(local, 0); + ieee80211_offchannel_return(local, + true, + false); + } + } else if (tmp_chan_changed) + /* Still off-channel, but on some other + * channel, so update hardware. + * PS should already be off-channel. + */ + ieee80211_hw_config(local, 0); + started = true; wk->timeout = jiffies; } @@ -1011,9 +1037,27 @@ static void ieee80211_work_work(struct work_struct *work) } if (!remain_off_channel && local->tmp_channel) { + bool on_oper_chan = ieee80211_cfg_on_oper_channel(local); local->tmp_channel = NULL; - ieee80211_hw_config(local, 0); - ieee80211_offchannel_return(local, true); + /* If tmp_channel wasn't operating channel, then + * we need to go back on-channel. + * NOTE: If we can ever be here while scannning, + * or if the hw_config() channel config logic changes, + * then we may need to do a more thorough check to see if + * we still need to do a hardware config. Currently, + * we cannot be here while scanning, however. + */ + if (ieee80211_cfg_on_oper_channel(local) && !on_oper_chan) + ieee80211_hw_config(local, 0); + + /* At the least, we need to disable offchannel_ps, + * so just go ahead and run the entire offchannel + * return logic here. We *could* skip enabling + * beaconing if we were already on-oper-channel + * as a future optimization. + */ + ieee80211_offchannel_return(local, true, true); + /* give connection some time to breathe */ run_again(local, jiffies + HZ/2); }