From 520eb82076993b7f55ef9b80771d264272e5127b Mon Sep 17 00:00:00 2001 From: Kalle Valo Date: Thu, 18 Dec 2008 23:35:27 +0200 Subject: [PATCH] mac80211: implement dynamic power save This patch implements dynamic power save for mac80211. Basically it means enabling power save mode after an idle period. Implementing it dynamically gives a good compromise of low power consumption and low latency. Some hardware have support for this in firmware, but some require the host to do it. The dynamic power save is implemented by adding an timeout to ieee80211_subif_start_xmit(). The timeout can be enabled from userspace with Wireless Extensions. For example, the command below enables the dynamic power save and sets the time timeout to 500 ms: iwconfig wlan0 power timeout 500m Power save now only works with devices which handle power save in firmware. It's also disabled by default and the heuristics when and how to enable is considered as a policy decision and will be left for the userspace to handle. In case the firmware has support for this, drivers can disable this feature with IEEE80211_HW_NO_STACK_DYNAMIC_PS. Big thanks to Johannes Berg for the help with the design and code. Signed-off-by: Kalle Valo Acked-by: Johannes Berg Signed-off-by: John W. Linville --- include/net/mac80211.h | 6 +++++ net/mac80211/ieee80211_i.h | 10 ++++++++ net/mac80211/main.c | 7 ++++++ net/mac80211/mlme.c | 49 ++++++++++++++++++++++++++++++++++++-- net/mac80211/tx.c | 13 ++++++++++ net/mac80211/wext.c | 30 +++++++++++++++-------- 6 files changed, 103 insertions(+), 12 deletions(-) diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 9428d3e2f11..b3bd00a9d99 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -854,6 +854,11 @@ enum ieee80211_tkip_key_type { * * @IEEE80211_HW_AMPDU_AGGREGATION: * Hardware supports 11n A-MPDU aggregation. + * + * @IEEE80211_HW_NO_STACK_DYNAMIC_PS: + * Hardware which has dynamic power save support, meaning + * that power save is enabled in idle periods, and don't need support + * from stack. */ enum ieee80211_hw_flags { IEEE80211_HW_RX_INCLUDES_FCS = 1<<1, @@ -866,6 +871,7 @@ enum ieee80211_hw_flags { IEEE80211_HW_NOISE_DBM = 1<<8, IEEE80211_HW_SPECTRUM_MGMT = 1<<9, IEEE80211_HW_AMPDU_AGGREGATION = 1<<10, + IEEE80211_HW_NO_STACK_DYNAMIC_PS = 1<<11, }; /** diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index a74d6738b30..f3eec989662 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -540,6 +540,7 @@ enum { enum queue_stop_reason { IEEE80211_QUEUE_STOP_REASON_DRIVER, + IEEE80211_QUEUE_STOP_REASON_PS, }; /* maximum number of hardware queues we support. */ @@ -693,7 +694,12 @@ struct ieee80211_local { */ int wifi_wme_noack_test; unsigned int wmm_acm; /* bit field of ACM bits (BIT(802.1D tag)) */ + bool powersave; + int dynamic_ps_timeout; + struct work_struct dynamic_ps_enable_work; + struct work_struct dynamic_ps_disable_work; + struct timer_list dynamic_ps_timer; #ifdef CONFIG_MAC80211_DEBUGFS struct local_debugfsdentries { @@ -977,6 +983,10 @@ int ieee80211_set_freq(struct ieee80211_sub_if_data *sdata, int freq); u64 ieee80211_mandatory_rates(struct ieee80211_local *local, enum ieee80211_band band); +void ieee80211_dynamic_ps_enable_work(struct work_struct *work); +void ieee80211_dynamic_ps_disable_work(struct work_struct *work); +void ieee80211_dynamic_ps_timer(unsigned long data); + void ieee80211_wake_queues_by_reason(struct ieee80211_hw *hw, enum queue_stop_reason reason); void ieee80211_stop_queues_by_reason(struct ieee80211_hw *hw, diff --git a/net/mac80211/main.c b/net/mac80211/main.c index 21335382f53..24b14363d6e 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -729,6 +729,13 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len, INIT_DELAYED_WORK(&local->scan_work, ieee80211_scan_work); + INIT_WORK(&local->dynamic_ps_enable_work, + ieee80211_dynamic_ps_enable_work); + INIT_WORK(&local->dynamic_ps_disable_work, + ieee80211_dynamic_ps_disable_work); + setup_timer(&local->dynamic_ps_timer, + ieee80211_dynamic_ps_timer, (unsigned long) local); + sta_info_init(local); tasklet_init(&local->tx_pending_tasklet, ieee80211_tx_pending, diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index dac8bd37dcf..5ba721b6a39 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -745,8 +745,14 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata, ieee80211_bss_info_change_notify(sdata, bss_info_changed); if (local->powersave) { - local->hw.conf.flags |= IEEE80211_CONF_PS; - ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); + if (local->dynamic_ps_timeout > 0) + mod_timer(&local->dynamic_ps_timer, jiffies + + msecs_to_jiffies(local->dynamic_ps_timeout)); + else { + conf->flags |= IEEE80211_CONF_PS; + ieee80211_hw_config(local, + IEEE80211_CONF_CHANGE_PS); + } } netif_tx_start_all_queues(sdata->dev); @@ -866,6 +872,9 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata, local->oper_channel_type = NL80211_CHAN_NO_HT; config_changed |= IEEE80211_CONF_CHANGE_HT; + del_timer_sync(&local->dynamic_ps_timer); + cancel_work_sync(&local->dynamic_ps_enable_work); + if (local->hw.conf.flags & IEEE80211_CONF_PS) { local->hw.conf.flags &= ~IEEE80211_CONF_PS; config_changed |= IEEE80211_CONF_CHANGE_PS; @@ -2593,3 +2602,39 @@ void ieee80211_mlme_notify_scan_completed(struct ieee80211_local *local) ieee80211_restart_sta_timer(sdata); rcu_read_unlock(); } + +void ieee80211_dynamic_ps_disable_work(struct work_struct *work) +{ + struct ieee80211_local *local = + container_of(work, struct ieee80211_local, + dynamic_ps_disable_work); + + if (local->hw.conf.flags & IEEE80211_CONF_PS) { + local->hw.conf.flags &= ~IEEE80211_CONF_PS; + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); + } + + ieee80211_wake_queues_by_reason(&local->hw, + IEEE80211_QUEUE_STOP_REASON_PS); +} + +void ieee80211_dynamic_ps_enable_work(struct work_struct *work) +{ + struct ieee80211_local *local = + container_of(work, struct ieee80211_local, + dynamic_ps_enable_work); + + if (local->hw.conf.flags & IEEE80211_CONF_PS) + return; + + local->hw.conf.flags |= IEEE80211_CONF_PS; + + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); +} + +void ieee80211_dynamic_ps_timer(unsigned long data) +{ + struct ieee80211_local *local = (void *) data; + + queue_work(local->hw.workqueue, &local->dynamic_ps_enable_work); +} diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index b098c58d216..a4af3a124cc 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1473,6 +1473,19 @@ int ieee80211_subif_start_xmit(struct sk_buff *skb, goto fail; } + if (!(local->hw.flags & IEEE80211_HW_NO_STACK_DYNAMIC_PS) && + local->dynamic_ps_timeout > 0) { + if (local->hw.conf.flags & IEEE80211_CONF_PS) { + ieee80211_stop_queues_by_reason(&local->hw, + IEEE80211_QUEUE_STOP_REASON_PS); + queue_work(local->hw.workqueue, + &local->dynamic_ps_disable_work); + } + + mod_timer(&local->dynamic_ps_timer, jiffies + + msecs_to_jiffies(local->dynamic_ps_timeout)); + } + nh_pos = skb_network_header(skb) - skb->data; h_pos = skb_transport_header(skb) - skb->data; diff --git a/net/mac80211/wext.c b/net/mac80211/wext.c index f6640d04715..7162d5816f3 100644 --- a/net/mac80211/wext.c +++ b/net/mac80211/wext.c @@ -833,7 +833,7 @@ static int ieee80211_ioctl_siwpower(struct net_device *dev, struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); struct ieee80211_conf *conf = &local->hw.conf; - int ret = 0; + int ret = 0, timeout = 0; bool ps; if (sdata->vif.type != NL80211_IFTYPE_STATION) @@ -841,6 +841,7 @@ static int ieee80211_ioctl_siwpower(struct net_device *dev, if (wrq->disabled) { ps = false; + timeout = 0; goto set; } @@ -850,22 +851,31 @@ static int ieee80211_ioctl_siwpower(struct net_device *dev, case IW_POWER_ALL_R: /* If explicitely state all */ ps = true; break; - default: /* Otherwise we don't support it */ - return -EINVAL; + default: /* Otherwise we ignore */ + break; } - if (ps == local->powersave) - return ret; + if (wrq->flags & IW_POWER_TIMEOUT) + timeout = wrq->value / 1000; set: + if (ps == local->powersave && timeout == local->dynamic_ps_timeout) + return ret; + local->powersave = ps; + local->dynamic_ps_timeout = timeout; if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) { - if (local->powersave) - conf->flags |= IEEE80211_CONF_PS; - else - conf->flags &= ~IEEE80211_CONF_PS; - + if (!(local->hw.flags & IEEE80211_HW_NO_STACK_DYNAMIC_PS) && + local->dynamic_ps_timeout > 0) + mod_timer(&local->dynamic_ps_timer, jiffies + + msecs_to_jiffies(local->dynamic_ps_timeout)); + else { + if (local->powersave) + conf->flags |= IEEE80211_CONF_PS; + else + conf->flags &= ~IEEE80211_CONF_PS; + } ret = ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); } -- 2.41.1