From patchwork Wed Jan 26 20:37:18 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ben Greear X-Patchwork-Id: 509811 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id p0QKbaaU014509 for ; Wed, 26 Jan 2011 20:37:36 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754112Ab1AZUhc (ORCPT ); Wed, 26 Jan 2011 15:37:32 -0500 Received: from mail.candelatech.com ([208.74.158.172]:58601 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752732Ab1AZUhc (ORCPT ); Wed, 26 Jan 2011 15:37:32 -0500 Received: from localhost.localdomain (firewall.candelatech.com [70.89.124.249]) by ns3.lanforge.com (8.14.2/8.14.2) with ESMTP id p0QKbJUw022801 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 26 Jan 2011 12:37:19 -0800 From: greearb@candelatech.com To: linux-wireless@vger.kernel.org Cc: Ben Greear Subject: [RFC v3] mac80211: Optimize scans on current operating channel. Date: Wed, 26 Jan 2011 12:37:18 -0800 Message-Id: <1296074238-4012-1-git-send-email-greearb@candelatech.com> X-Mailer: git-send-email 1.7.2.3 Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Wed, 26 Jan 2011 20:37:36 +0000 (UTC) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index c47d7c0..9508486 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -660,6 +660,10 @@ struct tpt_led_trigger { * that the scan completed. * @SCAN_ABORTED: Set for our scan work function when the driver reported * a scan complete for an aborted scan. + * @SCAN_LEFT_OPER_CHANNEL: Set this flag if the scan process leaves the + * operating channel at any time. If scanning ONLY the current operating + * channel this flag should not be set, and this will allow fewer + * offchannel changes. */ enum { SCAN_SW_SCANNING, @@ -667,6 +671,7 @@ enum { SCAN_OFF_CHANNEL, SCAN_COMPLETED, SCAN_ABORTED, + SCAN_LEFT_OPER_CHANNEL, }; /** @@ -1147,7 +1152,10 @@ 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); +/* Returns true if hardware is currently configured for the operating channel + * and if the logical configured state is to be on the operating channel. + */ +bool ieee80211_on_oper_channel(struct ieee80211_local *local); void ieee80211_offchannel_stop_station(struct ieee80211_local *local); void ieee80211_offchannel_return(struct ieee80211_local *local, bool enable_beaconing); diff --git a/net/mac80211/main.c b/net/mac80211/main.c index 09a2744..1e845c5 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -98,6 +98,39 @@ static void ieee80211_reconfig_filter(struct work_struct *work) ieee80211_configure_filter(local); } +/** If we are configured to be off the operating channel, + * or if we are already off the operating channel, return + * false. + */ +bool ieee80211_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 +143,27 @@ 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 || @@ -183,6 +222,7 @@ int ieee80211_hw_config(struct ieee80211_local *local, u32 changed) return ret; } + void ieee80211_bss_info_change_notify(struct ieee80211_sub_if_data *sdata, u32 changed) { @@ -231,7 +271,8 @@ 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(SCAN_OFF_CHANNEL, &local->scanning) || + !ieee80211_on_oper_channel(local)) { sdata->vif.bss_conf.enable_beacon = false; } else { /* diff --git a/net/mac80211/offchannel.c b/net/mac80211/offchannel.c index b4e5267..0441b16 100644 --- a/net/mac80211/offchannel.c +++ b/net/mac80211/offchannel.c @@ -95,57 +95,33 @@ 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_station(struct ieee80211_local *local) { 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 */ + /* 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); - netif_tx_stop_all_queues(sdata->dev); - } - } - mutex_unlock(&local->iflist_mtx); -} - -void ieee80211_offchannel_stop_station(struct ieee80211_local *local) -{ - 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) { + if (sdata->vif.type != NL80211_IFTYPE_MONITOR) { set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state); netif_tx_stop_all_queues(sdata->dev); - if (sdata->u.mgd.associated) + if ((sdata->vif.type == NL80211_IFTYPE_STATION) && + sdata->u.mgd.associated) ieee80211_offchannel_ps_enable(sdata); } + } mutex_unlock(&local->iflist_mtx); } @@ -181,7 +157,7 @@ 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 f36d70f..76b3a68 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -388,6 +388,7 @@ ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx) struct ieee80211_local *local = rx->local; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); struct sk_buff *skb = rx->skb; + int ret; if (likely(!(status->rx_flags & IEEE80211_RX_IN_SCAN))) return RX_CONTINUE; @@ -396,10 +397,14 @@ ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx) 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) + ret = ieee80211_scan_rx(rx->sdata, skb); + /* drop all the other packets while scanning off channel */ + if (ret != RX_QUEUED && + test_bit(SCAN_OFF_CHANNEL, &local->scanning)) { dev_kfree_skb(skb); - return RX_QUEUED; + return RX_QUEUED; + } + return ret; } /* scanning finished during invoking of handlers */ @@ -2749,7 +2754,7 @@ 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 f246d8a..b2eca7e 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -294,11 +294,14 @@ static void __ieee80211_scan_completed_finish(struct ieee80211_hw *hw, { struct ieee80211_local *local = hw_to_local(hw); - ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); + if ((local->oper_channel != local->hw.conf.channel) || was_hw_scan) + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); + if (!was_hw_scan) { ieee80211_configure_filter(local); drv_sw_scan_complete(local); - ieee80211_offchannel_return(local, true); + if (test_bit(SCAN_LEFT_OPER_CHANNEL, &local->scanning)) + ieee80211_offchannel_return(local, true); } mutex_lock(&local->mtx); @@ -398,13 +401,10 @@ 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); + __clear_bit(SCAN_LEFT_OPER_CHANNEL, &local->scanning); ieee80211_configure_filter(local); @@ -544,7 +544,18 @@ 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 (local->oper_channel == local->hw.conf.channel) { + if (next_chan == local->oper_channel) + 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; + } else { /* * we're currently scanning a different channel, let's * see if we can scan another channel without interfering @@ -560,7 +571,6 @@ 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), @@ -578,12 +588,6 @@ 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; @@ -592,9 +596,12 @@ 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) { + /* This must be set before we do the stop_station logic. */ + __set_bit(SCAN_OFF_CHANNEL, &local->scanning); + ieee80211_offchannel_stop_station(local); - __set_bit(SCAN_OFF_CHANNEL, &local->scanning); + __set_bit(SCAN_LEFT_OPER_CHANNEL, &local->scanning); /* * What if the nullfunc frames didn't arrive? @@ -641,8 +648,10 @@ 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; + + if (chan != local->hw.conf.channel) + 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/work.c b/net/mac80211/work.c index 36305e0..62ffc8e 100644 --- a/net/mac80211/work.c +++ b/net/mac80211/work.c @@ -924,18 +924,17 @@ 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); - local->tmp_channel = wk->chan; local->tmp_channel_type = wk->chan_type; - ieee80211_hw_config(local, 0); + if (!ieee80211_on_oper_channel(local)) { + /* + * Leave the station vifs in awake mode if they + * happen to be on the same channel as + * the requested channel + */ + ieee80211_offchannel_stop_station(local); + ieee80211_hw_config(local, 0); + } started = true; wk->timeout = jiffies; }